Science.gov

Sample records for latitude-dependent solar wind

  1. Latitude-Dependent Temperature Variations at the Solar Limb

    NASA Astrophysics Data System (ADS)

    Fivian, M. D.; Hudson, H. S.; Lin, R. P.; Zahid, H. J.

    2009-12-01

    We use observations from the solar aspect sensor of RHESSI to characterize the latitude dependence of the temperature of the photosphere at the solar limb. Previous observations have suggested the presence of a polar temperature excess as large as 1.5 K. The RHESSI observations, made with a rotating telescope in space, have great advantages in the rejection of systematic errors in the very precise photometry required for such an observation. This photometry is differential, i.e. relative to a mean limb-darkening function. The data base consists of about 1,000 images per day from linear CCDs with 1.73 arc sec square pixels, observing a narrow band (12nm FWHM) at 670 nm. Each image shows a chord crossing the disk at a different location as the spacecraft rotates and precesses around its average solar pointing. We fit an average limb-darkening function and reassemble the residuals into synoptic maps of differential intensity variations as function of position angle. We further mask these images against SOHO/EIT 284A images in order to eliminate magnetic regions. The analysis establishes a limit on the quadrupole dependence of temperature (brightness) on position angle of 0.04 +/- 0.02 K. This results in a possible correction of our precise measurement of the solar oblateness which is smaller than its rms error of 0.14 mas.

  2. Latitude-Dependent Temperature Variations at the Solar Limb

    NASA Astrophysics Data System (ADS)

    Fivian, Martin; Hudson, H. S.; Lin, R. P.; Zahid, H. J.

    2009-05-01

    We use observations from the solar aspect sensor of RHESSI to characterize the latitude dependence of the temperature of the photosphere at the solar limb. Previous observations have suggested the presence of a polar temperature excess as large as 1.5 K. The RHESSI observations, made with a rotating telescope in space, have great advantages in the rejection of systematic errors in the very precise photometry required for such an observation. This photometry is differential, i.e. relative to a mean limb-darkening function. The data base consists of about 1,000 images per day from linear CCDs with 1.73 arc sec square pixels, observing a narrow band (12nm FWHM) at 670 nm. Each image shows a chord crossing the disk at a different location as the spacecraft rotates and precesses around its average solar pointing. We fit an average limb-darkening function and reassemble the residuals into synoptic maps of differential intensity variations as function of position angle. We further mask these images against SOHO/EIT 284A images in order to eliminate magnetic regions. The analysis establishes limits on the quadrupole dependence of brightness (temperature) on position angle, a crucial unknown in our precise measurement of the solar oblateness.

  3. Depth and latitude dependence of the solar internal angular velocity

    NASA Technical Reports Server (NTRS)

    Rhodes, Edward J., Jr.; Cacciani, Alessandro; Korzennik, Sylvain; Tomczyk, Steven; Ulrich, Roger K.; Woodard, Martin F.

    1990-01-01

    One of the design goals for the dedicated helioseismology observing state located at Mount Wilson Observatory was the measurement of the internal solar rotation using solar p-mode oscillations. In this paper, the first p-mode splittings obtained from Mount Wilson are reported and compared with those from several previously published studies. It is demonstrated that the present splittings agree quite well with composite frequency splittings obtained from the comparisons. The splittings suggest that the angular velocity in the solar equatorial plane is a function of depth below the photosphere. The latitudinal differential rotation pattern visible at the surface appears to persist at least throughout the solar convection zone.

  4. Depth and latitude dependence of the solar internal angular velocity

    SciTech Connect

    Rhodes, E.J. Jr.; Cacciani, A.; Korzennik, S.; Tomczyk, S.; Ulrich, R.K.; Woodard, M.F. JPL, Pasadena, CA Roma I Universita California Univ., Los Angeles )

    1990-03-01

    One of the design goals for the dedicated helioseismology observing state located at Mount Wilson Observatory was the measurement of the internal solar rotation using solar p-mode oscillations. In this paper, the first p-mode splittings obtained from Mount Wilson are reported and compared with those from several previously published studies. It is demonstrated that the present splittings agree quite well with composite frequency splittings obtained from the comparisons. The splittings suggest that the angular velocity in the solar equatorial plane is a function of depth below the photosphere. The latitudinal differential rotation pattern visible at the surface appears to persist at least throughout the solar convection zone. 43 refs.

  5. Time trends and latitude dependence of uveal and cutaneous malignant melanoma induced by solar radiation

    SciTech Connect

    Moan, J.; Setlow, R.; Cicarma, E.; Porojnicu, A. C.; Grant, W. B.; Juzeniene, A.

    2010-01-01

    In order to evaluate the role of solar radiation in uveal melanoma etiology, the time and latitude dependency of the incidence rates of this melanoma type were studied in comparison with those of cutaneous malignant melanoma (CMM). Norway and several other countries with Caucasian populations were included. There is a marked north - south gradient of the incidence rates of CMM in Norway, with three times higher rates in the south than in the north. No such gradient is found for uveal melanoma. Similar findings have been published for CMM in other Caucasian populations, with the exception of Europe as a whole. In most populations the ratios of uveal melanoma incidence rates to those of CMM tend to decrease with increasing CMM rates. This is also true for Europe, in spite of the fact that in this region there is an inverse latitude gradient of CMM, with higher rates in the north than in the south. In Norway the incidence rates of CMM have increased until about 1990 but have been constant, or even decreased (for young people) after that time, indicating constant or decreasing sun exposure. The uveal melanoma rates have been increasing after 1990. In most other populations the incidence rates of CMM have been increasing until recently while those of uveal melanoma have been decreasing. These data generally support the assumption that uveal melanomas are not generated by ultraviolet (UV) radiation and that solar UV, via its role in vitamin D photosynthesis, may have a protective effect.

  6. Latitude-Dependent Effects in the Stellar Wind of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Smith, Nathan; Davidson, Kris; Gull, Theodore R.; Ishibashi, Kazunori; Hillier, D. John

    2002-01-01

    The Homunculus reflection nebula around eta Carinae provides the rare opportunity to observe the spectrum of a star from more than one direction. In the case of eta Car, the nebula's geometry is known well enough to infer how wind profiles vary with latitude. We present STIS spectra of several positions in the Homunculus, showing directly that eta Car has an aspherical and axisymmetric stellar wind. P Cygni absorption in Balmer lines depends on latitude, with relatively high velocities and strong absorption near the polar axis. Stronger absorption at high latitudes is surprising, and it suggests higher mass flux toward the poles, perhaps resulting from equatorial gravity darkening on a rotating star. Reflected profiles of He I lines are more puzzling, and offer clues to eta Car's wind geometry and ionization structure. During eta Car's high-excitation state in March 2000, the wind had a fast, dense polar wind, with higher ionization at low latitudes. Older STIS data obtained since 1998 reveal that this global stellar-wind geometry changes during eta Car's 5.5 year cycle, and may suggest that this star s spectroscopic events are shell ejections. Whether or not a companion star triggers these outbursts remains ambiguous. The most dramatic changes in the wind occur at low latitudes, while the dense polar wind remains relatively undisturbed during an event. The apparent stability of the polar wind also supports the inferred bipolar geometry. The wind geometry and its variability have critical implications for understanding the 5.5 year cycle and long-term variability, but do not provide a clear alternative to the binary hypothesis for generating eta Car s X-rays.

  7. A COMPANION AS THE CAUSE OF LATITUDE-DEPENDENT EFFECTS IN THE WIND OF ETA CARINAE

    SciTech Connect

    Groh, J. H.; Madura, T. I.; Weigelt, G.; Hillier, D. J.; Kruip, C. J. H.

    2012-11-01

    We analyze spatially resolved spectroscopic observations of the Eta Carinae binary system obtained with the Hubble Space Telescope/STIS. Eta Car is enshrouded by the dusty Homunculus nebula, which scatters light emitted by the central binary and provides a unique opportunity to study a massive binary system from different vantage points. We investigate the latitudinal and azimuthal dependence of H{alpha} line profiles caused by the presence of a wind-wind collision (WWC) cavity created by the companion star. Using two-dimensional radiative transfer models, we find that the wind cavity can qualitatively explain the observed line profiles around apastron. Regions of the Homunculus which scatter light that propagated through the WWC cavity show weaker or no H{alpha} absorption. Regions scattering light that propagated through a significant portion of the primary wind show stronger P Cygni absorption. Our models overestimate the H{alpha} absorption formed in the primary wind, which we attribute to photoionization by the companion, not presently included in the models. We can qualitatively explain the latitudinal changes that occur during periastron, shedding light on the nature of Eta Car's spectroscopic events. Our models support the idea that during the brief period of time around periastron when the primary wind flows unimpeded toward the observer, H{alpha} absorption occurs in directions toward the central object and Homunculus SE pole, but not toward equatorial regions close to the Weigelt blobs. We suggest that observed latitudinal and azimuthal variations are dominated by the companion star via the WWC cavity, rather than by rapid rotation of the primary star.

  8. Mapping the latitude dependence of the primary stellar wind of eta Carinae using the spectrum reflected on the Homunculus nebula

    NASA Astrophysics Data System (ADS)

    Odessey, Rachel

    2016-01-01

    The binary star Eta Carinae underwent a massive eruption in the 1840s, resulting in a huge nebula of ejected material, called the Homunculus. Despite preventing us from the direct view from the central source, the Homunculus acts like a mirror, allowing us to see the spectrum of the central binary system from different stellar latitudes. Therefore, by mapping the spectrum along the nebula we are actually probing the dependence of the spectrum with stellar latitude. Our project focuses on the P Cyg absorption component of H lines mostly in the optical and near-infrared wavelengths. in order to investigate the structure of the primary stellar wind. A full spectral mapping of the entire nebula was constructed by combining multiple dithered long slit observations using the ESO/X-Shooter high-resolution spectrograph. Such mapping allowed us to assemble a data cube containing the spectrum of each position along the nebula. Preliminary analysis confirms that the primary wind indeed has a deeper absorption component at high stellar latitudes (polar region). Also, contrary to our expectations, our analysis indicates that the polar region does not seem entirely radially symmetric in terms of density, which invites further investigation into the source of these discrepancies.

  9. Solar wind

    NASA Astrophysics Data System (ADS)

    Marsch, E.; Axford, W. I.; McKenzie, J. F.

    There are three major types of solar wind - the steady fast wind, the unsteady slow wind, and the variable transient wind. The fast streams are the normal modes of the solar wind. Their basic properties can be reproduced by multi-fluid models involving waves. After briefly reviewing the history of the subject and describing some of the modern theories of the fast wind, the boundary conditions and in-situ constraints are discussed which are imposed on the models, in particular by Ulysses at high latitudes. Some of the results are then presented from SOHO observations that have brought a wealth of new information on the state of the wind in the inner corona as well as the plasma source conditions prevailing in the transition region and solar chromosphere. Finally, problem areas are identified and future research perspectives are outlined.

  10. Solar Wind Five

    NASA Technical Reports Server (NTRS)

    Neugebauer, M. (editor)

    1983-01-01

    Topics of discussion were: solar corona, MHD waves and turbulence, acceleration of the solar wind, stellar coronae and winds, long term variations, energetic particles, plasma distribution functions and waves, spatial dependences, and minor ions.

  11. Solar Wind Magnetic Fields

    NASA Technical Reports Server (NTRS)

    Smith, E. J.

    1995-01-01

    The magnetic fields originate as coronal fields that are converted into space by the supersonic, infinitely conducting, solar wind. On average, the sun's rotation causes the field to wind up and form an Archimedes Spiral. However, the field direction changes almost continuously on a variety of scales and the irregular nature of these changes is often interpreted as evidence that the solar wind flow is turbulent.

  12. Latitude dependence of co-rotating shock acceleration

    NASA Technical Reports Server (NTRS)

    Gold, R. E.; Lanzerotti, L. J.; Maclennan, C. G.; Krimigis, S. M.

    1985-01-01

    Energetic particle observations in the outer heliosphere (approx 12 A. U.) by the LECP instruments on the Voyager 1 and Voyager 2 spacecraft are discussed that show a definite latitude dependence of the number and intensity of particle enhancements produced by corotating interplanetary regions during an interval when no solar energetic particle events were observed. The particle enhancements are fewer in number and less intense at higher (approx 20 deg.) heliolatitudes. However, the similar spectral shapes of the accelerated particles at the two spacecraft indicate that the acceleration process is the same at the two latitudes, but less intense at the higher latitude.

  13. The Solar Wind

    NASA Technical Reports Server (NTRS)

    Herring, J. R.; Licht, A. L.

    1960-01-01

    Parker's model of a spherically expanding corona, the "solar wind," is compared with D. E. Blackwell's observations of the 1954 minimum equatorial corona. A significant discrepancy is found between the predicted and the observed electron densities at distances from the sun greater than 20 solar radii. Blackwell's data are found to be consistent with a model in which the corona expands mostly within a disk less than 25 solar radii thick, lying within the sun's equatorial plane. The thickness of the disk as a function of distance from the sun is qualitatively explained in terms of magnetic pressure. The solar wind is found to have a considerable effect on the lunar atmosphere. First, the calculated density of the lunar atmosphere is greatly reduced by collisions with protons in the solar wind. If the flux of particles in this wind has the conventional values ranging between 10(exp 10) to 10(exp 11) per sq cm-sec, the calculations yield a lunar pressure of 10(exp -13) atmosphere of argon, in agreement with the value predicted by Elsmore and Whitfield on the basis of observations on the occultation of radio stars. Second, following a suggestion by Gold, it was found that the collisions of solar-wind protons with the lunar surface produce an atmosphere of cold neutral hydrogen with a density of 10(exp 5) per cu cm at the lunar surface. The density falls off at greater distances in accordance with the inverse-square law. Estimates indicate that the interaction of solar particles with the neutral hydrogen will produce an extended lunar ionosphere with a density of the order of 400 protons/cu cm in the vicinity of the moon.

  14. Latitude dependence of narrow bipolar pulse emissions

    NASA Astrophysics Data System (ADS)

    Ahmad, M. R.; Esa, M. R. M.; Cooray, V.; Baharudin, Z. A.; Hettiarachchi, P.

    2015-06-01

    In this paper, we present a comparative study on the occurrence of narrow bipolar pulses (NBPs) and other forms of lightning flashes across various geographical areas ranging from northern regions to the tropics. As the latitude decreased from Uppsala, Sweden (59.8°N) to South Malaysia (1.5°N), the percentage of NBP emissions relative to the total number of lightning flashes increased significantly from 0.13% to 12%. Occurrences of positive NBPs were more common than negative NBPs at all observed latitudes. However, as latitudes decreased, the negative NBP emissions increased significantly from 20% (Uppsala, Sweden) to 45% (South Malaysia). Factors involving mixed-phase region elevations and vertical extents of thundercloud tops are invoked to explain the observed results. These factors are fundamentally latitude dependent. Our results suggest that the NBP emission rate is not a useful measure to monitor thunderstorm severity because regular tropical thunderstorms, where relatively high NBP emissions occur, lack suitable conditions to become severe (i.e., there is modest convective available potential energy and a lack of baroclinity in such regions). Observations of significantly high negative NBP occurrences together with very rare occurrences of positive cloud-to-ground flashes and isolated breakdown pulses in tropical thunderstorms are indicative of a stronger negative screening layer magnitude and weaker lower positive charge region magnitude than those in northern regions.

  15. Petrovay: Solar physics Solar wind and heliosphere THE SOLAR WIND AND THE HELIOSPHERE

    E-print Network

    Petrovay, Kristóf

    Petrovay: Solar physics Solar wind and heliosphere THE SOLAR WIND AND THE HELIOSPHERE 1951: First radial (aberration effect). 1958: Parker's supersonic wind model 1962: Mariner-2 detects solar wind. v shock. 2012: V1 crosses heliopause. #12;Petrovay: Solar physics Solar wind and heliosphere Reminder

  16. Acceleration of the solar wind

    NASA Technical Reports Server (NTRS)

    Barnes, Aaron

    1992-01-01

    Different approaches to understanding the physics of solar wind acceleration are reviewed. Particular attention is given to fundamental reasons for a supersonic wind concept; the concept of thermal conduction as the primary energy transport mechanism in the solar wind; coronal holes as the source of wind and alternative acceleration mechanisms; and the state of closure of theory and observation.

  17. 77 FR 61597 - Avalon Wind, LLC; Avalon Wind 2, LLC; Catalina Solar, LLC; Catalina Solar 2, LLC; Pacific Wind...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-10

    ...EL12-109-000] Avalon Wind, LLC; Avalon Wind 2, LLC; Catalina Solar, LLC; Catalina Solar 2, LLC; Pacific Wind Lessee, LLC; Pacific Wind 2, LLC...planned capacity of the Petitioners' wind and solar generation projects to the...

  18. Latitude-dependent sensitivity to stationary perturbations in simple climate models

    NASA Technical Reports Server (NTRS)

    Salmun, H.; Cahalan, R. F.; North, G. R.

    1980-01-01

    The steady-state zonally averaged climate is perturbed by adding a latitude-dependent heat source to an energy balance equation of the simplified Budyko-Sellers type. The latitude of the ice edge, which is attached to an isotherm, becomes dependent on the strength of the perturbation. This dependence is given in terms of the well-known iceline-solar constant relation, and the latitude dependence of the perturbed temperature field is then uniquely determined. The exact analytical solution is linearized and expressed in terms of a superposition of line sources at various latitudes. The main features are: (1) The total temperature response is a sum of the direct effect of the perturbation and an indirect ice-albedo effect proportional to the solar ice-edge sensitivity; and (2) the indirect feedback effect produces an enhanced response in polar latitudes.

  19. Solar wind and magnetosphere interactions

    NASA Technical Reports Server (NTRS)

    Russell, C. T.; Allen, J. H.; Cauffman, D. P.; Feynman, J.; Greenstadt, E. W.; Holzer, R. E.; Kaye, S. M.; Slavin, J. A.; Manka, R. H.; Rostoker, G.

    1979-01-01

    The relationship between the magnetosphere and the solar wind is addressed. It is noted that this interface determines how much of the solar plasma and field energy is transferred to the Earth's environment, and that this coupling not only varies in time, responding to major solar disturbances, but also to small changes in solar wind conditions and interplanetary field directions. It is recommended that the conditions of the solar wind and interplanetary medium be continuously monitored, as well as the state of the magnetosphere. Other recommendations include further study of the geomagnetic tail, tests of Pc 3,4 magnetic pulsations as diagnostics of the solar wind, and tests of kilometric radiation as a remote monitor of the auroral electrojet.

  20. The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle

    E-print Network

    Richardson, John

    The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle Matthias R. Aellig Alamos National Lab., Los Alamos, NM 87545 Abstract We investigate the helium abundance in the solar wind a clear dependency of the He/H ratio in the solar wind on the solar cycle. In the slow solar wind

  1. Wind and solar powered turbine

    NASA Technical Reports Server (NTRS)

    Wells, I. D.; Koh, J. L.; Holmes, M. (inventors)

    1984-01-01

    A power generating station having a generator driven by solar heat assisted ambient wind is described. A first plurality of radially extendng air passages direct ambient wind to a radial flow wind turbine disposed in a centrally located opening in a substantially disc-shaped structure. A solar radiation collecting surface having black bodies is disposed above the fist plurality of air passages and in communication with a second plurality of radial air passages. A cover plate enclosing the second plurality of radial air passages is transparent so as to permit solar radiation to effectively reach the black bodies. The second plurality of air passages direct ambient wind and thermal updrafts generated by the black bodies to an axial flow turbine. The rotating shaft of the turbines drive the generator. The solar and wind drien power generating system operates in electrical cogeneration mode with a fuel powered prime mover.

  2. Wind and Solar Curtailment: Preprint

    SciTech Connect

    Lew, D.; Bird, L.; Milligan, M.; Speer, B.; Wang, X.; Carlini, E. M.; Estanqueiro, A.; Flynn, D.; Gomez-Lazaro, E.; Menemenlis, N.; Orths, A.; Pineda, I.; Smith, J. C.; Soder, L.; Sorensen, P.; Altiparmakis, A.; Yoh, Y.

    2013-09-01

    High penetrations of wind and solar generation on power systems are resulting in increasing curtailment. Wind and solar integration studies predict increased curtailment as penetration levels grow. This paper examines experiences with curtailment on bulk power systems internationally. It discusses how much curtailment is occurring, how it is occurring, why it is occurring, and what is being done to reduce curtailment. This summary is produced as part of the International Energy Agency Wind Task 25 on Design and Operation of Power Systems with Large Amounts of Wind Power.

  3. 77 FR 61597 - Avalon Wind, LLC; Avalon Wind 2, LLC; Catalina Solar, LLC; Catalina Solar 2, LLC; Pacific Wind...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-10

    ... Energy Regulatory Commission Avalon Wind, LLC; Avalon Wind 2, LLC; Catalina Solar, LLC; Catalina Solar 2, LLC; Pacific Wind Lessee, LLC; Pacific Wind 2, LLC; Valentine Solar, LLC; EDF Renewable Development..., LLC, Avalon Wind 2, LLC, Catalina Solar, LLC, Catalina Solar 2, LLC, Pacific Wind Lessee, LLC,...

  4. Highly Alfvenic Slow Solar Wind

    NASA Technical Reports Server (NTRS)

    Roberts, D. Aaron

    2010-01-01

    It is commonly thought that fast solar wind tends to be highly Alfvenic, with strong correlations between velocity and magnetic fluctuations, but examples have been known for over 20 years in which slow wind is both Alfvenic and has many other properties more typically expected of fast solar wind. This paper will present a search for examples of such flows from more recent data, and will begin to characterize the general characteristics of them. A very preliminary search suggests that such intervals are more common in the rising phase of the solar cycle. These intervals are important for providing constraints on models of solar wind acceleration, and in particular the role waves might or might not play in that process.

  5. STATIONARITY IN SOLAR WIND FLOWS

    SciTech Connect

    Perri, S.; Balogh, A. E-mail: a.balogh@imperial.ac.u

    2010-05-01

    By using single-point measurements in space physics it is possible to study a phenomenon only as a function of time. This means that we cannot have direct access to information about spatial variations of a measured quantity. However, the investigation of the properties of turbulence and of related phenomena in the solar wind widely makes use of an approximation frequently adopted in hydrodynamics under certain conditions, the so-called Taylor hypothesis; indeed, the solar wind flow has a bulk velocity along the radial direction which is much higher than the velocity of a single turbulent eddy embedded in the main flow. This implies that the time of evolution of the turbulent features is longer than the transit time of the flow through the spacecraft position, so that the turbulent field can be considered frozen into the solar wind flow. This assumption allows one to easily associate time variations with spatial variations and stationarity to homogeneity. We have investigated, applying criteria for weak stationarity to Ulysses magnetic field data in different solar wind regimes, at which timescale and under which conditions the hypothesis of stationarity, and then of homogeneity, of turbulence in the solar wind is well justified. We extend the conclusions of previous studies by Matthaeus and Goldstein to different parameter ranges in the solar wind. We conclude that the stationarity assumption in the inertial range of turbulence on timescales of 10 minutes to 1 day is reasonably satisfied in fast and uniform solar wind flows, but that in mixed, interacting fast, and slow solar wind streams the assumption is frequently only marginally valid.

  6. Wind in the Solar System

    ERIC Educational Resources Information Center

    McIntosh, Gordon

    2010-01-01

    As an astronomy instructor I am always looking for commonly experienced Earthly phenomena to help my students and me understand and appreciate similar occurrences elsewhere in the solar system. Recently I wrote short "TPT" articles on frost and precipitation. The present article is on winds in the solar system. A windy day or storm might motivate…

  7. Solar wind theory and modelling

    NASA Technical Reports Server (NTRS)

    Hansteen, Viggo H.

    1995-01-01

    The outflow of coronal plasma into interplanetary space is a consequence of the coronal heating process. Therefore the formation of the corona and the acceleration of the solar wind should be treated as a single problem. Traditionally the mass or particle flux emanating from the extended corona has been thought of as being determined by the coronal temperature or scale height and the coronal (base) density. This argument follows from considerations of the momentum balance of the corona-wind system from which one obtains models of a close to hydrostatic corona out to the critical point where the flow becomes supersonic. With this approach to the acceleration of the wind is has been difficult to reconcile the relatively small variation observed in the proton flux at 1 AU with the predicted exponential dependence of the proton flux on the coronal temperature. In this talk we would like to emphasize another approach in which coronal energetics play the primary role. The deposition of energy into the corona through some 'mechanical' energy flux is balanced by the various energy sinks available to the corona and the sum of these processes determine the coronal structure, i.e. its temperature and density. The corona loses energy through heat conduction into the transition region, through radiative losses, and through the gravitational potential energy and kinetic energy put into the solar wind itself. We will show from a series of models of the chromosphere transition region-corona-solar wind system that most of the energy deposited in a magnetically open region will go into the solar wind, with roughly half going into kinetic energy and half into lifting the plasma out of the solar gravity field. The coronal base density will adjust itself in such a way that the heat conductive flux flowing into the transition region is radiated away in the upper chromosphere. The coronal temperature is set by the requirements that most of the deposited energy goes into accelerating the solar wind; the coronal scale height will adjust itself so that the solar wind energy losses conform to the amplitude of the input energy. These processes are modified by the 'mode' of energy deposition, and we will show the effects on coronal structure of changing the parameters describing coronal heating as well as the effects of including a helium fluid in the models. However, the location, scale height and/or form of the energy deposition (i.e. heating or direct acceleration) are not too important for the solar wind, the coronal density and temperature structure will vary with the 'mode' of energy deposition, but the solar wind mass flux depends mainly on the amplitude of the energy flux.

  8. Photoionization in the Solar Wind

    NASA Astrophysics Data System (ADS)

    Landi, E.; Lepri, S. T.

    2015-10-01

    In this work we investigate the effects of photoionization on the charge state composition of the solar wind. Using measured solar EUV and X-ray irradiance, the Michigan Ionization Code and a model for the fast and slow solar wind, we calculate the evolution of the charge state distribution of He, C, N, O, Ne, Mg, Si, S, and Fe with and without including photoionization for both types of wind. We find that the solar radiation has significant effects on the charge state distribution of C, N, and O, causing the ionization levels of these elements to be higher than without photoionization; differences are largest for oxygen. The ions commonly observed for elements heavier than O are much less affected, except in ICMEs where Fe ions more ionized than 16+ can also be affected by the solar radiation. We also show that the commonly used O7+/O6+ density ratio is the most sensitive to photoionization; this sensitivity also causes the value of this ratio to depend on the phase of the solar cycle. We show that the O7+/O6+ ratio needs to be used with caution for solar wind classification and coronal temperature estimates, and recommend the C6+/C4+ ratio for these purposes.

  9. Solar wind absorption by Venus

    NASA Technical Reports Server (NTRS)

    Gombosi, T. I.; Cravens, T. E.; Nagy, A. F.; Elphic, R. C.; Russell, C. T.

    1980-01-01

    The portion of solar wind interacting with the dayside ionosphere and atmosphere of Venus was determined based on magnetic field fluctuations in the ionosheath and the interaction with the upper neutral atmosphere above the ionopause. Fluctuations with the ratio of the number of particles intersecting the daytide ionopause to the total number of particles of 0.3 suggest that about 0.3% of solar wind may be absorbed. Most of fast H atoms resulting from the charge exchange interactions with the atmosphere escape; some of the energy deposition processes produce observable signatures (such as a narrow Lyman alpha emission region), but penetrating solar wind particles do not control the physical and/or chemical structure of the daytime Venus ionosphere.

  10. Solar wind electron density and temperature over solar cycle 23: Thermal noise measurements on Wind

    E-print Network

    California at Berkeley, University of

    Solar wind electron density and temperature over solar cycle 23: Thermal noise measurements on Wind; received in revised form 6 April 2005; accepted 25 April 2005 Abstract We present the solar wind plasma parameters obtained from the Wind spacecraft during more than nine years, encompassing almost the whole solar

  11. Turbulence of the Solar Wind Studies of the Solar Wind Using the ACE and Helios Spacecraft

    E-print Network

    Turbulence of the Solar Wind Studies of the Solar Wind Using the ACE and Helios Spacecraft Bejamin;Abstract The solar wind is a supersonic ow of plasma emanating from the sun and traveling through the interplanetary medium to the outermost reaches of the heliosphere. The solar wind experiences in situ

  12. Recognizing Reconnection in the Solar Wind:Recognizing Reconnection in the Solar Wind: The Magnetopause Connection

    E-print Network

    Strangeway, Robert J.

    Recognizing Reconnection in the Solar Wind:Recognizing Reconnection in the Solar WindSuppressed when the Magnetosheath Beta is Large Scurry et al 1994Scurry et al. 1994 #12;Some Suggested Solar Wind throughout the solar wind ..." Leading Edge of ICMEs TurbulenceGenerated Current Sheets Matthaeus et al

  13. RELATED LINKS Photos: Solar & Wind

    E-print Network

    RELATED LINKS Photos: Solar & Wind Power for the Home Photos: Energy Efficiency for the Home Photos for Special Home Features is Declining Washington, D.C. ­ October 6, 2009 ­ In light of the downturn maintenance produces, while showing a lessened interest in special features such as home theaters, guest wings

  14. Imaging the Variable Solar Wind

    NASA Astrophysics Data System (ADS)

    DeForest, C.; Howard, T. A.; Matthaeus, W. H.

    2013-05-01

    With the advent of wide-field Thomson scattering imagery from STEREO/SECCHI, it is possible to image the solar wind continuously from its origin in the low corona to large fractions of 1AU from the Sun. Although it is sensitive only to non-stationary density structures, Thomson imaging yields morphological insight and global perspective that are not directly available from in-situ data. I will review recent work on both large and small scale analysis. On large scales, it is now possible to track well-presented CMEs from the pre-eruptive structure to impact with in-situ probes, yielding positive identification of flux rope structure based on both positively tracked morphology and direct magnetic measurement. In some cases, plasma detected in-situ can be positively identified with particular pieces of pre-eruptive anatomy in the low corona. Some observed large-scale features are as-yet unexplained. In quiet solar wind, small ejecta and blobs are readily distinguished from disconnection events that may be identified by their morphology, and all can be tracked through the Alfvén surface boundary at 20-50 Rs into the solar wind proper. In the HI-1 field of view, the solar wind takes on a flocculated appearance, though most of the individual features lose image structure and cannot be tracked across the entire field of view. Analysis of individual ejecta and of the statistical properties of the flocculation pattern is yielding insights into the nature of fluctuations and origin of variability in the slow solar wind.

  15. Eight-moment approximation solar wind models

    NASA Technical Reports Server (NTRS)

    Olsen, Espen Lyngdal; Leer, Egil

    1995-01-01

    Heat conduction from the corona is important in the solar wind energy budget. Until now all hydrodynamic solar wind models have been using the collisionally dominated gas approximation for the heat conductive flux. Observations of the solar wind show particle distribution functions which deviate significantly from a Maxwellian, and it is clear that the solar wind plasma is far from collisionally dominated. We have developed a numerical model for the solar wind which solves the full equation for the heat conductive flux together with the conservation equations for mass, momentum, and energy. The equations are obtained by taking moments of the Boltzmann equation, using an 8-moment approximation for the distribution function. For low-density solar winds the 8-moment approximation models give results which differ significantly from the results obtained in models assuming the gas to be collisionally dominated. The two models give more or less the same results in high density solar winds.

  16. Solar wind plasma : kinetic properties and micro-instabilities

    E-print Network

    Kasper, Justin Christophe, 1977-

    2003-01-01

    The kinetic properties of ions in the solar wind plasma are studied. Observations of solar wind +H and +2He by the Faraday Cup instrument component of the Solar Wind Experiment on the Wind spacecraft show that these ions ...

  17. The Heating & Acceleration of the Solar Wind

    E-print Network

    Wurtele, Jonathan

    The Heating & Acceleration of the Solar Wind Eliot Quataert (UC Berkeley) Collaborators: Steve & Slow Winds · The Puzzle of the High Frequency Cascade (or the lack thereof ....) · Possible Solutions #12;Background · Heating required to accelerate the solar wind · Early models invoked e- conduction

  18. MAGNETOHYDRODYNAMIC SIMULATIONS OF THE SOLAR CORONA AND SOLAR WIND USING A BOUNDARY TREATMENT TO LIMIT SOLAR WIND MASS FLUX

    E-print Network

    California at Berkeley, University of

    MAGNETOHYDRODYNAMIC SIMULATIONS OF THE SOLAR CORONA AND SOLAR WIND USING A BOUNDARY TREATMENT TO LIMIT SOLAR WIND MASS FLUX Keiji Hayashi W. W. Hansen Experimental Physics Laboratory, Stanford ABSTRACT Magnetohydrodynamic simulations of the solar corona and solar wind are sensitive to conditions

  19. Name _____________________ Lab 10. Solar and Wind Power

    E-print Network

    Perfect, Ed

    1 Name _____________________ Lab 10. Solar and Wind Power INTRODUCTION Sunlight can be used such as wind power or geothermal energy. In addition, desert ecosystems may be disturbed by large solar arrays to create heat or generate electrical power. This is referred to as solar energy. It is a clean form

  20. Comet Borrelly Slows Solar Wind

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Over 1300 energy spectra taken on September 22, 2001 from the ion and electron instruments on NASA's Deep Space 1 span a region of 1,400,000 kilometers (870,000 miles) centered on the closest approach to the nucleus of comet Borrelly. A very strong interaction occurs between the solar wind (horizontal red bands to left and right in figure) and the comet's surrounding cloud of dust and gas, the coma. Near Deep Space 1's closest approach to the nucleus, the solar wind picked up charged water molecules from the coma (upper green band near the center), slowing the wind sharply and creating the V-shaped energy structure at the center.

    Deep Space 1 completed its primary mission testing ion propulsion and 11 other advanced, high-risk technologies in September 1999. NASA extended the mission, taking advantage of the ion propulsion and other systems to undertake this chancy but exciting, and ultimately successful, encounter with the comet. More information can be found on the Deep Space 1 home page at http://nmp.jpl.nasa.gov/ds1/ .

    Deep Space 1 was launched in October 1998 as part of NASA's New Millennium Program, which is managed by JPL for NASA's Office of Space Science, Washington, D.C. The California Institute of Technology manages JPL for NASA.

  1. Observations of solar-wind helium

    NASA Technical Reports Server (NTRS)

    Neugebauer, M.

    1981-01-01

    It is pointed out that the concentration of helium in the solar wind relative to hydrogen fluctuates wildly. Under certain circumstances, the helium to hydrogen abundance ratio is strongly enhanced over probable solar values; at other times, the amount of helium in the solar wind is immeasurably small. In spite of the fact that helium is heavier than hydrogen, solar-wind helium often leaves the solar gravitational field with a higher velocity than does the hydrogen. It is thought that the mechanisms responsible for helium behavior may contain clues to unanswered questions concerning the acceleration and energy exchange processes of the entire solar wind. A brief review is given of the principal features and theories of the solar wind as a whole. In addition, measurement techniques are discussed. Emphasis throughout is on the experimental data concerning the dynamics of solar-wind helium. On the basis of coronal temperatures, it is shown that helium in the solar wind is almost always doubly ionized. It is also shown that the average abundance of helium ions in the solar wind is usually in the range of 3 to 6% by number.

  2. Solar energy tracking structure incorporating wind spoilers

    SciTech Connect

    Frohardt, M.W.; Hartz, K.H.; Hardee, P.C.

    1989-12-19

    This patent describes a solar energy tracking assembly. The assembly producing reduced torque loading forces due to wind on the rotating portion of the tracking assembly. The solar energy tracking assembly comprised of: a fixed position base having one end securely fixed to the ground and having the second end supporting the remaining tracking assembly components; solar energy collecting means comprising a moving structure frame and at least one solar collecting element attached thereto means for rotating the solar energy collecting means in relation to the sun in order that the solar energy collecting means maintain the proper attitude for collection of incident solar energy; and a wind spoiler assembly.

  3. Solar wind tans young asteroids

    NASA Astrophysics Data System (ADS)

    2009-04-01

    A new study published in Nature this week reveals that asteroid surfaces age and redden much faster than previously thought -- in less than a million years, the blink of an eye for an asteroid. This study has finally confirmed that the solar wind is the most likely cause of very rapid space weathering in asteroids. This fundamental result will help astronomers relate the appearance of an asteroid to its actual history and identify any after effects of a catastrophic impact with another asteroid. ESO PR Photo 16a/09 Young Asteroids Look Old "Asteroids seem to get a ‘sun tan' very quickly," says lead author Pierre Vernazza. "But not, as for people, from an overdose of the Sun's ultraviolet radiation, but from the effects of its powerful wind." It has long been known that asteroid surfaces alter in appearance with time -- the observed asteroids are much redder than the interior of meteorites found on Earth [1] -- but the actual processes of this "space weathering" and the timescales involved were controversial. Thanks to observations of different families of asteroids [2] using ESO's New Technology Telescope at La Silla and the Very Large Telescope at Paranal, as well as telescopes in Spain and Hawaii, Vernazza's team have now solved the puzzle. When two asteroids collide, they create a family of fragments with "fresh" surfaces. The astronomers found that these newly exposed surfaces are quickly altered and change colour in less than a million years -- a very short time compared to the age of the Solar System. "The charged, fast moving particles in the solar wind damage the asteroid's surface at an amazing rate [3]", says Vernazza. Unlike human skin, which is damaged and aged by repeated overexposure to sunlight, it is, perhaps rather surprisingly, the first moments of exposure (on the timescale considered) -- the first million years -- that causes most of the aging in asteroids. By studying different families of asteroids, the team has also shown that an asteroid's surface composition is an important factor in how red its surface can become. After the first million years, the surface "tans" much more slowly. At that stage, the colour depends more on composition than on age. Moreover, the observations reveal that collisions cannot be the main mechanism behind the high proportion of "fresh" surfaces seen among near-Earth asteroids. Instead, these "fresh-looking" surfaces may be the results of planetary encounters, where the tug of a planet has "shaken" the asteroid, exposing unaltered material. Thanks to these results, astronomers will now be able to understand better how the surface of an asteroid -- which often is the only thing we can observe -- reflects its history. More information This result was presented in a paper published this week in the journal Nature, "Solar wind as the origin of rapid reddening of asteroid surfaces", by P. Vernazza et al. The team is composed of Pierre Vernazza (ESA), Richard Binzel (MIT, Cambridge, USA), Alessandro Rossi (ISTI-CNR, Pisa, Italy), Marcello Fulchignoni (Paris Observatory, France), and Mirel Birlan (IMCCE, CNRS-8028, Paris Observatory, France). A PDF file can be downloaded here. Notes [1] Meteorites are small fragments of asteroids that fall on Earth. While a meteorite enters the Earth's atmosphere its surface can melt and be partially charred by the intense heat. Nevertheless, the meteorite interior remains unaffected, and can be studied in a laboratory, providing a wealth of information on the nature and composition of asteroids. [2] An asteroid family is a group of asteroids that are on similar orbits around the Sun. The members of a given family are believed to be the fragments of a larger asteroid that was destroyed during a collision. [3] The surface of an asteroid is affected by the highly energetic particles forming the solar wind. These particles partially destroy the molecules and crystals on the surface, re-arranging them in other combinations. Over time, these changes

  4. Sources of solar wind over the solar activity cycle.

    PubMed

    Poletto, Giannina

    2013-05-01

    Fast solar wind has been recognized, about 40 years ago, to originate in polar coronal holes (CHs), that, since then, have been identified with sources of recurrent high speed wind streams. As of today, however, there is no general consensus about whether there are, within CHs, preferential locations where the solar wind is accelerated. Knowledge of slow wind sources is far from complete as well. Slow wind observed in situ can be traced back to its solar source by backward extrapolation of magnetic fields whose field lines are streamlines of the outflowing plasma. However, this technique often has not the necessary precision for an indisputable identification of the region where wind originates. As the Sun progresses through its activity cycle, different wind sources prevail and contribute to filling the heliosphere. Our present knowledge of different wind sources is here summarized. Also, a Section addresses the problem of wind acceleration in the low corona, as inferred from an analysis of UV data, and illustrates changes between fast and slow wind profiles and possible signatures of changes along the solar cycle. A brief reference to recent work about the deep roots of solar wind and their changes over different solar cycles concludes the review. PMID:25685421

  5. Sources of solar wind over the solar activity cycle

    PubMed Central

    Poletto, Giannina

    2012-01-01

    Fast solar wind has been recognized, about 40 years ago, to originate in polar coronal holes (CHs), that, since then, have been identified with sources of recurrent high speed wind streams. As of today, however, there is no general consensus about whether there are, within CHs, preferential locations where the solar wind is accelerated. Knowledge of slow wind sources is far from complete as well. Slow wind observed in situ can be traced back to its solar source by backward extrapolation of magnetic fields whose field lines are streamlines of the outflowing plasma. However, this technique often has not the necessary precision for an indisputable identification of the region where wind originates. As the Sun progresses through its activity cycle, different wind sources prevail and contribute to filling the heliosphere. Our present knowledge of different wind sources is here summarized. Also, a Section addresses the problem of wind acceleration in the low corona, as inferred from an analysis of UV data, and illustrates changes between fast and slow wind profiles and possible signatures of changes along the solar cycle. A brief reference to recent work about the deep roots of solar wind and their changes over different solar cycles concludes the review. PMID:25685421

  6. Expansion effects on solar wind hybrid simulations

    SciTech Connect

    Parashar, Tulasi N.; Velli, Marco; Goldstein, Bruce E.

    2013-06-13

    Ion kinetic simulations of the solar wind using hybrid codes can model local wave input, heating and instabilities, but generally do not include long term evolution effects in the expanding solar wind. We further develop the expanding box model used in earlier studies to include the mirror force effects and study their role in the evolution of the proton distribution functions in the outer corona and inner heliosphere. The mirror force, significant in the acceleration region of the solar wind, is required for consistency with the conservation of magnetic moment of particles in the expanding wind. We present preliminary results from the modified 1D expanding box hybrid (EBHM) simulations.

  7. Solar energy system with wind vane

    DOEpatents

    Grip, Robert E

    2015-11-03

    A solar energy system including a pedestal defining a longitudinal axis, a frame that is supported by the pedestal and that is rotateable relative to the pedestal about the longitudinal axis, the frame including at least one solar device, and a wind vane operatively connected to the frame to urge the frame relative to the pedestal about the longitudinal axis in response to wind acting on the wind vane.

  8. The distribution of solar wind speeds during solar minimum: Calibration for numerical solar wind modeling constraints on the source of the slow solar wind

    NASA Astrophysics Data System (ADS)

    McGregor, S. L.; Hughes, W. J.; Arge, C. N.; Owens, M. J.; Odstrcil, D.

    2011-03-01

    It took the solar polar passage of Ulysses in the early 1990s to establish the global structure of the solar wind speed during solar minimum. However, it remains unclear if the solar wind is composed of two distinct populations of solar wind from different sources (e.g., closed loops which open up to produce the slow solar wind) or if the fast and slow solar wind rely on the superradial expansion of the magnetic field to account for the observed solar wind speed variation. We investigate the solar wind in the inner corona using the Wang-Sheeley-Arge (WSA) coronal model incorporating a new empirical magnetic topology-velocity relationship calibrated for use at 0.1 AU. In this study the empirical solar wind speed relationship was determined by using Helios perihelion observations, along with results from Riley et al. (2003) and Schwadron et al. (2005) as constraints. The new relationship was tested by using it to drive the ENLIL 3-D MHD solar wind model and obtain solar wind parameters at Earth (1.0 AU) and Ulysses (1.4 AU). The improvements in speed, its variability, and the occurrence of high-speed enhancements provide confidence that the new velocity relationship better determines the solar wind speed in the outer corona (0.1 AU). An analysis of this improved velocity field within the WSA model suggests the existence of two distinct mechanisms of the solar wind generation, one for fast and one for slow solar wind, implying that a combination of present theories may be necessary to explain solar wind observations.

  9. Coronal Heating versus Solar Wind Acceleration

    E-print Network

    Steven R. Cranmer

    2004-09-29

    Parker's initial insights from 1958 provided a key causal link between the heating of the solar corona and the acceleration of the solar wind. However, we still do not know what fraction of the solar wind's mass, momentum, and energy flux is driven by Parker-type gas pressure gradients, and what fraction is driven by, e.g., wave-particle interactions or turbulence. SOHO has been pivotal in bringing these ideas back to the forefront of coronal and solar wind research. This paper reviews our current understanding of coronal heating in the context of the acceleration of the fast and slow solar wind. For the fast solar wind, a recent model of Alfven wave generation, propagation, and non-WKB reflection is presented and compared with UVCS, SUMER, radio, and in-situ observations at the last solar minimum. The derived fractions of energy and momentum addition from thermal and nonthermal processes are found to be consistent with various sets of observational data. For the more chaotic slow solar wind, the relative roles of steady streamer-edge flows (as emphasized by UVCS abundance analysis) versus bright blob structures (seen by LASCO) need to be understood before the relation between streamer heating and and slow-wind acceleration can be known with certainty. Finally, this presentation summarizes the need for next-generation remote-sensing observations that can supply the tight constraints needed to unambiguously characterize the dominant physics.

  10. Solar cycle changes in the high latitude solar wind

    NASA Technical Reports Server (NTRS)

    Rickett, B. J.; Coles, W. A.

    1980-01-01

    Measurements of the solar wind velocity during the period 1971-79 using the technique of interplanetary scintillation are discussed. The average wind speed was faster than 500 km/s at latitudes above 30 deg for most of 1973-77. The fast polar stream, observed to become much narrower in 1978-79 is examined. The narrowing of the polar streams coincided with the emergence of sunspots at midlatitudes, with the start of the new solar cycle, and with a corresponding contraction of the polar coronal holes. The theory that the solar magnetic field controls the large scale structure of the solar wind is discussed in relation to the results.

  11. Global network of slow solar wind

    NASA Astrophysics Data System (ADS)

    Crooker, N. U.; Antiochos, S. K.; Zhao, X.; Neugebauer, M.

    2012-04-01

    The streamer belt region surrounding the heliospheric current sheet (HCS) is generally treated as the primary or sole source of the slow solar wind. Synoptic maps of solar wind speed predicted by the Wang-Sheeley-Arge model during selected periods of solar cycle 23, however, show many areas of slow wind displaced from the streamer belt. These areas commonly have the form of an arc that is connected to the streamer belt at both ends. The arcs mark the boundaries between fields emanating from different coronal holes of the same polarity and thus trace the paths of belts of pseudostreamers, i.e., unipolar streamers that form over double arcades and lack current sheets. The arc pattern is consistent with the predicted topological mapping of the narrow open corridor or singular separator line that must connect the holes and, thus, consistent with the separatrix-web model of the slow solar wind. Near solar maximum, pseudostreamer belts stray far from the HCS-associated streamer belt and, together with it, form a global-wide web of slow wind. Recognition of pseudostreamer belts as prominent sources of slow wind provides a new template for understanding solar wind stream structure, especially near solar maximum.

  12. Global Network of Slow Solar Wind

    NASA Technical Reports Server (NTRS)

    Crooker, N. U.; Antiochos, S. K.; Zhao, X.; Neugebauer, M.

    2012-01-01

    The streamer belt region surrounding the heliospheric current sheet (HCS) is generally treated as the primary or sole source of the slow solar wind. Synoptic maps of solar wind speed predicted by the Wang-Sheeley-Arge model during selected periods of solar cycle 23, however, show many areas of slow wind displaced from the streamer belt. These areas commonly have the form of an arc that is connected to the streamer belt at both ends. The arcs mark the boundaries between fields emanating from different coronal holes of the same polarity and thus trace the paths of belts of pseudostreamers, i.e., unipolar streamers that form over double arcades and lack current sheets. The arc pattern is consistent with the predicted topological mapping of the narrow open corridor or singular separator line that must connect the holes and, thus, consistent with the separatrix-web model of the slow solar wind. Near solar maximum, pseudostreamer belts stray far from the HCS-associated streamer belt and, together with it, form a global-wide web of slow wind. Recognition of pseudostreamer belts as prominent sources of slow wind provides a new template for understanding solar wind stream structure, especially near solar maximum.

  13. Hydromagnetic heating in the solar wind

    NASA Technical Reports Server (NTRS)

    Hartle, R.

    1972-01-01

    Hydromagnetic heating in the solar wind was investigated using the heating model in which fast-mode hydromagnetic waves propagate outward from below the base and deposit energy by collisionless damping. Ray paths were found by solving Hamilton's equations. As the ray propagates along its path, it will damp, supplying thermal energy to the solar wind gas. The strong agreement of these results with observations is clear indication that the primary nonthermal heat source in the solar wind is the collisionless damping of hydromagnetic waves.

  14. DSCOVR High Time Resolution Solar Wind Measurements

    NASA Technical Reports Server (NTRS)

    Szabo, Adam

    2012-01-01

    The Deep Space Climate Observatory (DSCOVR), previously known as Triana, spacecraft is expected to be launched in late 2014. It will carry a fluxgate magnetometer, Faraday Cup solar wind detector and a top-hat electron electrostatic analyzer. The Faraday Cup will provide an unprecedented 10 vectors/sec time resolution measurement of the solar wind proton and alpha reduced distribution functions. Coupled with the 40 vector/sec vector magnetometer measurements, the identification of specific wave modes in the solar wind will be possible for the first time. The science objectives and data products of the mission will be discussed.

  15. Properties of the very slow solar wind

    NASA Astrophysics Data System (ADS)

    Sanchez-Diaz, Eduardo; Segura, Kevin; Rouillard, Alexis P.; Lavraud, Benoit

    2015-04-01

    Solar wind plasma data taken between 0.29-0.9 AU by the twin HELIOS spacecraft reveals the frequent occurrence of very low radial wind speeds (200 < V < 300 km/s), very rarely measured near 1 AU. By analysing the occurrence as a function of heliocentric distance and time, we show that it is primarly measured inside 0.5 AU and mostly during solar maximum, although some very slow wind events were also measured during short periods at solar minimum. We show that the very slow wind is frequently measured during the passage of the solar wind plasma sheet usually detected in the vicinity of the heliospheric current sheet. By tracing these slow events back to the Sun and using a potential field reconstruction of the coronal magnetic field based on magnetograms taken by Mount Wilson Observatory, we compare the speed of the very slow wind with the geometry of the magnetic flux tube at its source. We discuss theoretical mechanisms that could explain the abundance and origin of this very slow wind, we also stress the importance of these findings for our understanding of solar wind structure. This study was carried out as part of the HELCATS FP7 project.

  16. The Solar Wind and Its Interaction with the Interstellar Medium

    E-print Network

    Richardson, John

    The Solar Wind and Its Interaction with the Interstellar Medium John D. Richardson Abstract The solar wind is a magnetized plasma of ions and electrons which flows outward from the Sun. This chapter begins with a brief history of the discovery of the solar wind. Solar wind properties at 1 AU

  17. Global Network of Slow Solar Wind N. U. Crooker1

    E-print Network

    Zhao, Xuepu

    Global Network of Slow Solar Wind N. U. Crooker1 Center for Space Physics, Boston University of the slow solar wind. Synoptic maps of solar wind speed predicted by the Wang-Sheeley-Arge model during selected periods of solar cycle 23, however, show many areas of slow wind displaced from the streamer belt

  18. Turbulence in solar wind and laboratory plasmas

    SciTech Connect

    Carbone, V.

    2010-06-16

    Recent studies of plasma turbulence based on measurements within solar wind and laboratory plasmas has been discussed. Evidences for the presence of a turbulent energy cascade, using the Yaglom's law for MHD turbulence, has been provided through data from the Ulysses spacecraft. This allows, for the first time, a direct estimate of the turbulent energy transfer rate, which can contribute to the in situ heating of the solar wind. The energy cascade has been evidenced also for ExB electrostatic turbulence in laboratory magnetized plasmas using measurements of intermittent transport (bursty turbulence) at the edge of the RFX-mod reversed field pinch plasma device. Finally the problem of the dispersive region of turbulence in solar wind above the ion-cyclotron frequency, where a spectral break is usually observed, and the problem of dissipation in a collisionless fluid as the solar wind, are briefly discussed.

  19. The solar wind in the outer heliosphere

    E-print Network

    Richardson, John D.

    The solar wind evolves as it moves outward due to interactions with both itself and with the circum-heliospheric interstellar medium. The speed is, on average, constant out to 30 AU, then starts a slow decrease due to the ...

  20. Genesis Solar Wind Array Collector Cataloging Status

    NASA Astrophysics Data System (ADS)

    Burkett, P. J.; Rodriguez, M. C.; Calaway, M. C.; Allton, J. H.

    2009-03-01

    A focused characterization task was initiated in May 2008 to document the largest array fragments in the Genesis solar wind collection. To date, the collection consists of 3460 samples. By area, total percentage of cataloged array material is 18%.

  1. Solar Corona/Wind Composition and Origins of the Solar Wind

    NASA Astrophysics Data System (ADS)

    Lepri, S. T.; Gilbert, J. A.; Landi, E.; Shearer, P.; von Steiger, R.; Zurbuchen, T.

    2014-12-01

    Measurements from ACE and Ulysses have revealed a multifaceted solar wind, with distinctly different kinetic and compositional properties dependent on the source region of the wind. One of the major outstanding issues in heliophysics concerns the origin and also predictability of quasi-stationary slow solar wind. While the fast solar wind is now proven to originate within large polar coronal holes, the source of the slow solar wind remains particularly elusive and has been the subject of long debate, leading to models that are stationary and also reconnection based - such as interchange or so-called S-web based models. Our talk will focus on observational constraints of solar wind sources and their evolution during the solar cycle. In particular, we will point out long-term variations of wind composition and dynamic properties, particularly focused on the abundance of elements with low First Ionization Potential (FIP), which have been routinely measured on both ACE and Ulysses spacecraft. We will use these in situ observations, and remote sensing data where available, to provide constraints for solar wind origin during the solar cycle, and on their correspondence to predictions for models of the solar wind.

  2. Electrostatic Solitary Waves in the Solar Wind: Evidence for Instability at Solar Wind Current Sheets

    NASA Technical Reports Server (NTRS)

    Malaspina, David M.; Newman, David L.; Wilson, Lynn Bruce; Goetz, Keith; Kellogg, Paul J.; Kerstin, Kris

    2013-01-01

    A strong spatial association between bipolar electrostatic solitary waves (ESWs) and magnetic current sheets (CSs) in the solar wind is reported here for the first time. This association requires that the plasma instabilities (e.g., Buneman, electron two stream) which generate ESWs are preferentially localized to solar wind CSs. Distributions of CS properties (including shear angle, thickness, solar wind speed, and vector magnetic field change) are examined for differences between CSs associated with ESWs and randomly chosen CSs. Possible mechanisms for producing ESW-generating instabilities at solar wind CSs are considered, including magnetic reconnection.

  3. Magnetic energy flow in the solar wind.

    NASA Technical Reports Server (NTRS)

    Modisette, J. L.

    1972-01-01

    Discussion of the effect of rotation (tangential flow) of the solar wind on the conclusions of Whang (1971) suggesting an increase in the solar wind velocity due to the conversion of magnetic energy to kinetic energy. It is shown that the effect of the rotation of the sun on the magnetic energy flow results in most of the magnetic energy being transported by magnetic shear stress near the sun.

  4. Solar wind observations near the sun

    NASA Technical Reports Server (NTRS)

    Armstrong, J. W.; Coles, W. A.; Rickett, B. J.; Kojima, M.

    1986-01-01

    Observations of interplanetary scintillations with the VLA telescope are reported. The solar wind in the accelerating region from 3 to 12 solar radii was observed by scintillation of the radio source 3C279. The results obtained outside of 7 solar radii showed good agreement with previous work but observations between 3 and 4.5 solar radii were new and unexpected. Turbulence in the solar wind has a spatially anisotropic structure elongated in the radial direction, the flow direction being also in the radial direction. An abrupt change of both the velocity and the spatial anisotropy of turbulence was found at distances from 3 to 4.5 solar radii. There is a large random velocity component inside of 12 solar radii which is comparable to the bulk flow speed, and it has a spatially anisotropic probability distribution. From the measured cross-correlation functions, evidence which may be related to the complex structure of the magnetic field is found.

  5. Empirical Solar Wind Forecasting from the Chromosphere

    E-print Network

    Robert J. Leamon; Scott W. McIntosh

    2007-01-12

    Recently, we correlated the inferred structure of the solar chromospheric plasma topography with solar wind velocity and composition data measured at 1AU. We now offer a physical justification of these relationships and present initial results of a empirical prediction model based on them. While still limited by the fundamentally complex physics behind the origins of the solar wind and how its structure develops in the magnetic photosphere and expands into the heliosphere, our model provides a near continuous range of solar wind speeds and composition quantities that are simply estimated from the inferred structure of the chromosphere. We suggest that the derived quantities may provide input to other, more sophisticated, prediction tools or models such as those to study Coronal Mass Ejections (CME) propagation and Solar Energetic Particle (SEP) generation.

  6. Unique observations of a geomagnetic SI+ Solar sources and associated solar wind fluctuations

    E-print Network

    Padmanabhan, Janardhan

    Unique observations of a geomagnetic SI+ - SI- pair: Solar sources and associated solar wind- pair was closely correlated with corresponding variations in the solar wind density, while solar wind, the date corresponding to the traceback location of the solar wind flows. This event presents empirical

  7. Differential Flow Between Solar Wind Protons and Alpha Particles: First WIND Observations

    E-print Network

    Richardson, John

    Differential Flow Between Solar Wind Protons and Alpha J Particles: First WIND Observations . T with bulk - a solar wind flow speed. The detailed WIND measurements en ble us to investigate instances when, it is shown I here to also occur at 1 AU in the ecliptic. ntroduction The solar wind's two primary ion

  8. ELECTRON PROPERTIES AND COULOMB COLLISIONS IN THE SOLAR WIND AT 1 AU: WIND OBSERVATIONS

    E-print Network

    California at Berkeley, University of

    ELECTRON PROPERTIES AND COULOMB COLLISIONS IN THE SOLAR WIND AT 1 AU: WIND OBSERVATIONS C. Salem,1 in the solar wind has been the subject of several extensive analyses over the past 20 years. We analyze here the electron properties of the solar wind observed by the Wind satellite at 1 AU in the ecliptic plane, during

  9. Response of Solar Wind on Extreme Solar Activity

    NASA Astrophysics Data System (ADS)

    Suzuki, T. K.

    2015-09-01

    We investigate how the mass loss by the solar wind depends on the solar activity levels, particularly focusing on the solar wind during extremely high activity. We perform forward-type magnetohydrodynamical (MHD) numerical experiments for Alfvén wave-driven solar winds with a wide range of the input Poynting flux from the photosphere. Increasing the magnetic field strength and the turbulent velocity at the solar photosphere from the current solar level, the mass loss rate rapidly increases at first owing to the suppression of the reflection of the Alfvén waves. The surface materials are lifted up by the magnetic pressure associated with the Alfvén waves, and the cool dense chromosphere is extended to ? 10% of the stellar radius. The dense atmospheres enhance the radiative losses and eventually most of the input Poynting energy from the surface escapes by the radiation. As a result, there is no more sufficient energy remained for the kinetic energy of the wind; the solar wind saturates for the extreme activity level, as observed in Wood et al. The saturation level is positively correlated with the average magnetic field strength contributed from open flux tubes. If the field strength is a few times larger than the present level, the mass loss rate could be as high as 1000 times.

  10. Are There Natural Categories of Solar Wind?

    NASA Astrophysics Data System (ADS)

    Roberts, D. A.; Sipes, T.; Karimabadi, H.

    2014-12-01

    What seem to be the most obvious categories of solar wind, such as fast and slow, often turn out to be difficult to pin down on closer examination. For example, while slow winds tend to be dense and nonAlfvenic, there are significant exceptions, with some slow winds being not only very Alfvenic but also exhibiting many fast wind traits. Here we use "unsupervised" data mining to look for "natural" solar wind types. We use a set of variables to represent the state of the system and apply what are now standard algorithms to look for natural clustering of these variables. We have done this process for the solar wind density, speed, a carbon charge state ratio (6+ to 5+), the cross-helicity, and the "residual energy." When using the first three of these, we find two groups that tend to be slow and fast, but with the boundary between the groups that is a combination of speed and density. When all five variables are used, the best characterization of the states is as three basic groups in the cross-helicity vs residual energy space, i.e., in terms of "turbulence" measures rather than simple parameters. The three-variable case is largely but not completely reproduced in its subspace. We will suggest what the results could mean for the understanding of issues such as solar wind acceleration.

  11. Plasma dynamical processes in the solar wind

    NASA Astrophysics Data System (ADS)

    Bichter, A. K.

    Observations of proton and electron velcity distributions and of their moments at different radial distances from the Sun and in different parts of stream structured solar wind between 0.3 and 1 angstrom units are described. These observations are then compared with the corresponding results of theoretical studies on the plasma kinetics of a collisionless solar wind. The discrepancy deduced from these comparison then suggests that waves and their resonant interactions with these particles under consideration and instabilities of their distributions must play an important role in the physics of solar wind. In situ observations of these modes in the interplanetary medium are also discussed. Some of the theoretical results under which circumstances the proton and electron distribution might become unstable with respect to the ionacoustic mode are reviewed and some indirect observational evidence that these instabilities might indeed operate in the soalr wind are given.

  12. Solar Wind Forecasting with Coronal Holes

    E-print Network

    S. Robbins; C. J. Henney; J. W. Harvey

    2007-01-09

    An empirical model for forecasting solar wind speed related geomagnetic events is presented here. The model is based on the estimated location and size of solar coronal holes. This method differs from models that are based on photospheric magnetograms (e.g., Wang-Sheeley model) to estimate the open field line configuration. Rather than requiring the use of a full magnetic synoptic map, the method presented here can be used to forecast solar wind velocities and magnetic polarity from a single coronal hole image, along with a single magnetic full-disk image. The coronal hole parameters used in this study are estimated with Kitt Peak Vacuum Telescope He I 1083 nm spectrograms and photospheric magnetograms. Solar wind and coronal hole data for the period between May 1992 and September 2003 are investigated. The new model is found to be accurate to within 10% of observed solar wind measurements for its best one-month periods, and it has a linear correlation coefficient of ~0.38 for the full 11 years studied. Using a single estimated coronal hole map, the model can forecast the Earth directed solar wind velocity up to 8.5 days in advance. In addition, this method can be used with any source of coronal hole area and location data.

  13. New Horizons Solar Wind Around Pluto Solar Wind (SWAP) Measurements from 5 to 23 AU

    NASA Astrophysics Data System (ADS)

    Elliott, H. A.; McComas, D. J.; Delamere, P. A.

    2012-12-01

    This year the Solar Wind Around Pluto (SWAP) instrument on the New Horizons (NH) spacecraft collected 79 days of solar wind measurements during hibernation, about 30 days of data during annual checkout operations, and has begun recording another 168 days of data in hibernation which will be played back next year. The currently available NH-SWAP solar wind observations now span from about 5.1 to 23.4 AU. We examine how the peak solar wind speed in the New Horizons measurements vary with distance, report on progress toward automating the fitting of the SWAP solar wind count rate distributions, and take an initial look at the solar wind temperature-speed relationship beyond 11 AU. Since most of the SWAP solar wind observations were collected while spinning, and ions from the entire field-of-view (10 by 276 degrees) are focused onto one pair of coincidence Channel Electron Multiplier, we need to evaluate the effect of spinning on the measured rates. By comparing the 3-axis stabilized, to the rolling and spinning measurements, we strive to assess spin variations in the observed SWAP count rates and develop techniques to account for them. To test our analysis, we fit simulated count rate distributions to quantify how well our technique recovers the input solar wind conditions.

  14. PULSED ALFVEN WAVES IN THE SOLAR WIND

    SciTech Connect

    Gosling, J. T.; Tian, H.; Phan, T. D.

    2011-08-20

    Using 3 s plasma and magnetic field data from the Wind spacecraft located in the solar wind well upstream from Earth, we report observations of isolated, pulse-like Alfvenic disturbances in the solar wind. These isolated events are characterized by roughly plane-polarized rotations in the solar wind magnetic field and velocity vectors away from the directions of the underlying field and velocity and then back again. They pass over Wind on timescales ranging from seconds to several minutes. These isolated, pulsed Alfven waves are pervasive; we have identified 175 such events over the full range of solar wind speeds (320-550 km s{sup -1}) observed in a randomly chosen 10 day interval. The large majority of these events are propagating away from the Sun in the solar wind rest frame. Maximum field rotations in the interval studied ranged from 6 Degree-Sign to 109 Degree-Sign . Similar to most Alfvenic fluctuations in the solar wind at 1 AU, the observed changes in velocity are typically less than that predicted for pure Alfven waves (Alfvenicity ranged from 0.28 to 0.93). Most of the events are associated with small enhancements or depressions in magnetic field strength and small changes in proton number density and/or temperature. The pulse-like and roughly symmetric nature of the magnetic field and velocity rotations in these events suggests that these Alfvenic disturbances are not evolving when observed. They thus appear to be, and probably are, solitary waves. It is presently uncertain how these waves originate, although they may evolve out of Alfvenic turbulence.

  15. Turbulent density fluctuations in the solar wind

    E-print Network

    Ingale, Madhusudan

    2015-01-01

    Treatments of the radio scattering due to density turbulence in the solar wind typically employ asymptotic approximations to the phase structure function. We use a general structure function (GSF) that straddles the asymptotic limits and quantify the relative error introduced by the approximations. We show that the regimes where GSF predictions are accurate than those of its asymptotic approximations is not only of practical relevance, but are where inner scale effects influence the estimate of the scatter-broadening. Thus we propose that GSF should henceforth be used for scatter broadening calculations and estimates of quantities characterizing density turbulence in the solar corona and solar wind. In the next part of this thesis we use measurements of density turbulence in the solar wind from previously publish observations of radio wave scattering and interplanetary scintillations. Density fluctuations are inferred using the GSF for radio scattering data and existing analysis methods for IPS. Assuming that...

  16. Comparison of VLF Wave Activity in the Solar Wind During Solar Maximum and Minimum

    E-print Network

    California at Berkeley, University of

    Comparison of VLF Wave Activity in the Solar Wind During Solar Maximum and Minimum: Ulysses and intermediate speed solar wind. The maximum intensity of the electromagnetic waves for the two solar cycle are similar for the slow and intermediate solar wind in both solar maximum and minimum phases. It is also

  17. Radiation belt electrons respond to multiple solar wind inputs

    E-print Network

    Radiation belt electrons respond to multiple solar wind inputs E. J. Rigler,1 M. Wiltberger,1 and D wind input. We find that the solar wind bulk speed tends to be the primary driver of electron flux in the solar wind's magnetic field strength tend to temporarily reduce electron fluxes between L = 4 and L = 8

  18. Solar wind electron measurements from the Wind spacecraft

    NASA Astrophysics Data System (ADS)

    Bale, S. D.

    2014-12-01

    The Wind spacecraft has been on orbit for 20 years and produced a wealth solar wind science. In this talk, I will describe results from the Three Dimensional Plasma (3DP) instrument on Wind. In particular, we will use measurements of 1 AU electron distribution functions to show that the thermal electron bulk speed lags the proton speed and that this velocity difference is controlled by Coulomb collisions. By integrating the equation of dynamical friction back into the inner heliosphere, we infer that the plasma environment of the corona (within 20 Rs) is higher kinetic.

  19. Solar Metallicity Derived from in situ Solar Wind Composition

    NASA Astrophysics Data System (ADS)

    von Steiger, R.; Zurbuchen, T. H.

    2016-01-01

    We use recently released solar wind compositional data to determine the metallicity of the Sun—the fraction per unit mass that is composed of elements heavier than He. We focus on a present-day solar sample available to us, which is the least fractionated solar wind from coronal holes near the poles of the Sun. Using these data, we derive a metallicity of Z = 0.0196 ± 0.0014, which is significantly larger than recent published values based on photospheric spectroscopy, but consistent with results from helioseismology.

  20. The Solar Wind Ion Analyzer for MAVEN

    NASA Astrophysics Data System (ADS)

    Halekas, J. S.; Taylor, E. R.; Dalton, G.; Johnson, G.; Curtis, D. W.; McFadden, J. P.; Mitchell, D. L.; Lin, R. P.; Jakosky, B. M.

    2015-12-01

    The Solar Wind Ion Analyzer (SWIA) on the MAVEN mission will measure the solar wind ion flows around Mars, both in the upstream solar wind and in the magneto-sheath and tail regions inside the bow shock. The solar wind flux provides one of the key energy inputs that can drive atmospheric escape from the Martian system, as well as in part controlling the structure of the magnetosphere through which non-thermal ion escape must take place. SWIA measurements contribute to the top level MAVEN goals of characterizing the upper atmosphere and the processes that operate there, and parameterizing the escape of atmospheric gases to extrapolate the total loss to space throughout Mars' history. To accomplish these goals, SWIA utilizes a toroidal energy analyzer with electrostatic deflectors to provide a broad 360?×90? field of view on a 3-axis spacecraft, with a mechanical attenuator to enable a very high dynamic range. SWIA provides high cadence measurements of ion velocity distributions with high energy resolution (14.5 %) and angular resolution (3.75?×4.5? in the sunward direction, 22.5?×22.5? elsewhere), and a broad energy range of 5 eV to 25 keV. Onboard computation of bulk moments and energy spectra enable measurements of the basic properties of the solar wind at 0.25 Hz.

  1. Solar-wind minor ions: recent observations

    SciTech Connect

    Bame, S.J.

    1982-01-01

    During the years following the Solar Wind Four Conference at Burghausen our knowledge of the solar wind ion composition and dynamics has grown. There have been some surprises, and our understanding of the evolution of the solar wind has been improved. Systematic studies have shown that the minor ions generally travel with a common bulk speed and have temperatures roughly proportional to their masses. It has been determined that the /sup 3/He/sup + +/ content varies greatly; /sup 3/He/sup + +///sup 4/He/sup + +/ ranges from as high as 10/sup 2/ values to below 2 x 10/sup -4/. In some solar wind flows which can be related to energetic coronal events, the minor ions are found in unusual ionization states containing Fe/sup 16 +/ as a prominent ion, showing that the states were formed at unusually high temperatures. Unexpectedly, in a few flows substantial quantities of /sup 4/He/sup +/ have been detected, sometimes with ions identifiable as O/sup 2 +/ and O/sup 3 +/. Surprisingly, in some of these examples the ionization state is mixed showing that part of the plasma escaped the corona without attaining the usual million-degree temperatures while other parts were heated more nearly in the normal manner. Additionally, detailed studies of the minor ions have increased our understanding of the coronal expansion. For example, such studies have contributed to identifying near equatorial coronal streamers as the source of solar wind flows between high speed streams.

  2. Asymptotic Theory of Solar Wind Electrons

    NASA Astrophysics Data System (ADS)

    Kim, Sunjung; Yoon, Peter H.; Choe, G. S.; Wang, Linghua

    2015-06-01

    This paper presents a theory for the asymptotically steady-state solar wind electron velocity distribution function (VDF) in a local equilibrium with plasma wave turbulence. By treating the local solar wind electron VDF as a superposition of three populations—the low-energy Maxwellian core electrons with an energy range of tens of eV, the intermediate ˜ {{10}2}-103 eV energy-range halo electrons, and the high ˜ {{10}3}-105 eV energy-range superhalo electrons—the present paper puts forth a model in which the halo electrons are in dynamical steady state with the pervasive whistler fluctuations, while the superhalo electrons maintain dynamical steady-state equilibrium with the Langmuir fluctuations, known as the quasi-thermal noise. Customary models of the solar wind electrons include only the Maxwellian core and the halo (plus highly field-aligned strahl). While the present paper does not consider the strahl population in the discussion, the highly energetic superhalo component, which is observed to be present in all solar conditions, is explicitly taken into account as part of the total solar wind electron model. Comparisons with STEREO and WIND spacecraft observations are also made.

  3. Laboratory Facility for Simulating Solar Wind Sails

    SciTech Connect

    Funaki, Ikkoh; Ayabe, Tomohiro; Horisawa, Hideyuki; Yamakawa, Hiroshi

    2008-12-31

    Magnetic sail (MagSail) is a deep space propulsion system, in which an artificial magnetic cavity captures the energy of the solar wind to propel a spacecraft in the direction leaving the sun. For a scale-model experiment of the plasma flow of MagSail, we employed a magnetoplasmadynamic arcjet as a solar wind simulator. It is observed that a plasma flow from the solar wind simulator reaches a quasi-steady state of about 0.8 ms duration after a transient phase when initiating the discharge. During this initial phase of the discharge, a blast-wave was observed to develop radially in a vacuum chamber. When a solenoidal coil (MagSail scale model) is immersed into the quasi-steady flow where the velocity is 45 km/s, and the number density is 10{sup 19} m-3, a bow shock as well as a magnetic cavity were formed in front of the coil. As a result of the interaction between the plasma flow and the magnetic cavity, the momentum of the simulated solar wind is decreased, and it is found from the thrust measurement that the solar wind momentum is transferred to the coil simulating MagSail.

  4. Solar wind ion composition and charge states

    SciTech Connect

    Vonsteiger, R.

    1995-06-01

    The solar wind, a highly tenuous plasma streaming from the Sun into interplanetary space at supersonic speed, is roughly composed of 95% hydrogen and 5% helium by number. All other, heavy elements contribute less than 0.1% by number and thus are truly test particles Nevertheless, these particles provide valuable information not present in the main components. The authors first discuss the importance of the heavy ions as tracers for processes in the solar atmosphere. Specifically, their relative abundances are found to be different in the solar wind as compared to the photosphere. This fractionation, which is best organized as a function of the first ionization time (FIT) of the elements under solar surface conditions, provides information on the structure of the chromosphere, where it is imparted on the partially ionized material by an atom-ion separation mechanism. Moreover, the charge states of the heavy ions can be used to infer the coronal temperature, since they are frozen-in near the altitude where the expansion time scale overcomes the ionization/recombination time scales. Next, the authors review the published values of ion abundances in the solar wind, concentrating on the recent results of the SWICS instrument on Ulysses. About 8 elements and more than 20 charge states can be routinely analyzed by this sensor. There is clear evidence that both the composition and the charge state distribution is significantly different in the fast solar wind from the south polar coronal hole, traversed by Ulysses in 1993/94, as compared to the solar wind normally encountered near the ecliptic plane. The fractionation between low- and high-FIT elements is reduced, and the charge states indicate a lower, more uniform coronal temperature in the hole. Finally, the authors discuss these results in the framework of existing theoretical models of the chromosphere and corona, attempting to identify differences between the low- and high-latitude regions of the solar atmosphere.

  5. The Solar Wind in the Outer Heliosphere at Solar John D. Richardson and Chi Wang

    E-print Network

    Richardson, John

    (400 km/s) solar wind is con ned to a thin strip of half-width 10-20 near the heliographic equator wind speed, with the energy for this accel- eration coming from a slowdown of the solar windThe Solar Wind in the Outer Heliosphere at Solar Maximum John D. Richardson and Chi Wang Center

  6. Springfall asymmetry of substorm strength, geomagnetic activity and solar wind: Implications for semiannual variation and solar

    E-print Network

    Springfall asymmetry of substorm strength, geomagnetic activity and solar wind: Implications study the seasonal variation of substorms, geomag- netic activity and their solar wind drivers in 1993 highspeed streams dominate the solar wind. A similar, large annual variation is found in the solar wind

  7. Magnetofluid Turbulence in the Solar Wind

    NASA Technical Reports Server (NTRS)

    Goldstein, Melvyn L.

    2008-01-01

    The solar wind shows striking characteristics that suggest that it is a turbulent magnetofluid, but the picture is not altogether simple. From the earliest observations, a strong correlation between magnetic fluctuations and plasma velocity fluctuations was noted. The high corrections suggest that the fluctuations are Alfven waves. In addition, the power spectrum of the magnetic fluctuation showed evidence of an inertial range that resembled that seen in fully-developed fluid turbulence. Alfven waves, however, are exact solutions of the equations of incompressible magnetohydrodynamics. Thus, there was a puzzle: how can a magnetofluid consisting of Alfven waves be turbulent? The answer lay in the role of velocity shears in the solar wind that could drive turbulent evolution. Puzzles remain: for example, the power spectrum of the velocity fluctuations is less steep than the slope of the magnetic fluctuations, nor do we understand even now why the solar wind appears to be nearly incompressible with a -5/3 power-spectral index.

  8. Energy Dissipation Processes in Solar Wind Turbulence

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Wei, F. S.; Feng, X. S.; Xu, X. J.; Zhang, J.; Sun, T. R.; Zuo, P. B.

    2015-12-01

    Turbulence is a chaotic flow regime filled by irregular flows. The dissipation of turbulence is a fundamental problem in the realm of physics. Theoretically, dissipation ultimately cannot be achieved without collisions, and so how turbulent kinetic energy is dissipated in the nearly collisionless solar wind is a challenging problem. Wave particle interactions and magnetic reconnection (MR) are two possible dissipation mechanisms, but which mechanism dominates is still a controversial topic. Here we analyze the dissipation region scaling around a solar wind MR region. We find that the MR region shows unique multifractal scaling in the dissipation range, while the ambient solar wind turbulence reveals a monofractal dissipation process for most of the time. These results provide the first observational evidences for intermittent multifractal dissipation region scaling around a MR site, and they also have significant implications for the fundamental energy dissipation process.

  9. Energy dissipation processes in solar wind turbulence

    E-print Network

    Wang, Y; Feng, X S; Xu, X J; Zhang, J; Sun, T R; Zuo, P B

    2015-01-01

    Turbulence is a chaotic flow regime filled by irregular flows. The dissipation of turbulence is a fundamental problem in the realm of physics. Theoretically, dissipation cannot be ultimately achieved without collisions, and so how turbulent kinetic energy is dissipated in the nearly collisionless solar wind is a challenging problem. Wave particle interactions and magnetic reconnection are two possible dissipation mechanisms, but which mechanism dominates is still a controversial topic. Here we analyze the dissipation region scaling around a solar wind magnetic reconnection region. We find that the magnetic reconnection region shows a unique multifractal scaling in the dissipation range, while the ambient solar wind turbulence reveals a monofractal dissipation process for most of the time. These results provide the first observational evidences for the intermittent multifractal dissipation region scaling around a magnetic reconnection site, and they also have significant implications for the fundamental energy...

  10. Solar cycle evolution of the solar wind in three dimensions

    NASA Technical Reports Server (NTRS)

    Rickett, B. J.; Coles, W. A.

    1983-01-01

    Measurements of the solar wind speed both in and out of the ecliptic are presented for 1971-82. The speed estimates, which were made with the interplanetary scintillation system at UC San Diego, have been compared to in situ for large, slowly evolving structures, and thus such structures can be studied up to 60 degrees north and south heliographic latitude. Annual average wind speeds are presented versus latitude for an entire solar cycle. Fast wind streams from the poles persisted through declining and low solar activity, but were closed off during four years of high activity. This evolution follows that of the polar coronal holes, as displayed by comparing averaged speed and coronal density over latitude and longitude. The most recent data (1982) show the reestablishment of large tilted polar holes and associated fast streams. Coronal magnetic field data show that the neutral sheet is confined to low latitudes at solar minimum and extends to high latitudes at solar maximum; thus the slow solar wind comes from the same latitude range as that of the neutral sheet.

  11. Ion beaming in the solar wind: Wind Observations and Solar Probe Plus Challenges

    NASA Astrophysics Data System (ADS)

    Stevens, M. L.; Kasper, J. C.; Maruca, B. A.

    2011-12-01

    Observations of the micro-state of ions in the solar wind have revealed that double-streaming protons carry a significant portion of the kinetic energy in the inner heliosphere, and in fast/collisionally young wind. We present the results of a comprehensive investigation into field-aligned proton beams in the solar wind at 1 AU, as observed by the Solar Wind Explorer (SWE) on the Wind spacecraft. A re-analysis of the Wind SWE data set has recently been conducted in order to characterize features in the SWE velocity distribution function that are attributable to minor ions or to secondary proton and alpha components, including Alfvénic beams. The kinetic substructure of the SWE ion velocity distribution function (VDF) contains the fingerprints of heating processes in the solar wind and in the corona, however counter-streaming proton detections also provide evidence of ongoing plasma interpenetration at magnetic reconnection exhaust sites, providing insight into the mechanism in those structures. It is shown that about 40% of simple, so-called "quasi-steady" reconnection structure that can be readily identified in the solar wind at 1 AU is associated with proton beams. This suggests that magnetic reconnection in situ may be a significant source mechanism for ion beaming. Statistics of the Wind ion beam data set are presented in the context of candidate beam origination and dissipation mechanisms. The SPC/SPAN experiment on Solar Probe Plus will measure the solar wind micro-state in a new region of the heliosphere, improving in detail and in scope upon the previous observations from the Helios missions. By considering the collisional age of plasma streams with beam structure that are not readily attributable to an in situ mechanism, our study is also used to predict the ion VDF in the inner heliosphere as it will be measured by the SPC/SPAN experiment on Solar Probe Plus.

  12. Solar Wind Change Exchange from the Magnetosheath

    NASA Technical Reports Server (NTRS)

    Snowden, Steve

    2008-01-01

    We report the results of a long (approximately 100 ks) XMM-Newton observation designed to observe solar wind charge exchange emission (SWCX) from Earth's magnetosheath. By luck, the observation took place during a period of minimal solar wind flux so the SWCX emission was also minimal. Never-the-less, there is a significant if not stunning correlation between the observed O VIII count rate and our model for magnetosheath emission. We also report on the observed O VII and O VII emission.

  13. Workshop on Solar Activity, Solar Wind, Terrestrial Effects, and Solar Acceleration

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A summary of the proceedings from the workshop are presented. The areas covered were solar activity, solar wind, terrestrial effects, and solar acceleration. Specific topics addressed include: (1) solar cycle manifestations, both large and small scale, as well as long-term and short-term changes, including transients such as flares; (2) sources of solar wind, as identified by interplanetary observations including coronal mass ejections (CME's) or x-ray bright points, and the theory for and evolution of large-scale and small-scale structures; (3) magnetosphere responses, as observed by spacecraft, to variable solar wind and transient energetic particle emissions; and (4) origin and propagation of solar cosmic rays as related to solar activity and terrestrial effects, and solar wind coronal-hole relationships and dynamics.

  14. Solar wind electron temperature and density measurements on the Solar Orbiter with thermal noise spectroscopy

    E-print Network

    California at Berkeley, University of

    Solar wind electron temperature and density measurements on the Solar Orbiter with thermal noise Abstract The measurement of the solar wind electron temperature in the unexplored region between 1 and 45 Rs is of prime importance for understanding the solar wind acceleration. Solar OrbiterÕs location

  15. Solar wind observations at STEREO: 2007 - 2011

    NASA Astrophysics Data System (ADS)

    Jian, L. K.; Russell, C. T.; Luhmann, J. G.; Galvin, A. B.; Simunac, K. D. C.

    2013-06-01

    We have observed the solar wind extensively using the twin STEREO spacecraft in 2007 - 2011, covering the deep solar minimum 23/24 and the rising phase of solar cycle 24. Hundreds of large-scale solar wind structures have been surveyed, including stream interaction regions (SIRs), interplanetary CMEs (ICMEs), and interplanetary shocks. The difference in location can cause one STEREO spacecraft to encounter 1/3 more of the above structures than the other spacecraft in a single year, even of the quasi-steady SIRs. In contrast with the rising phase of cycle 23, SIRs and ICMEs have weaker field and pressure compression in this rising phase, and ICMEs drive fewer shocks. Although the majority of shocks are driven by SIRs and ICMEs, we find ~13% of shocks without clear drivers observed in situ.

  16. Solar Wind Interaction with Dusty Cometary Coma

    NASA Astrophysics Data System (ADS)

    Popel, S. I.; Gisko, A. A.; Losseva, T. V.; Vladimirov, S. V.

    Interaction of Solar wind with dusty cometary coma is considered. In contrast to previous descriptions of this interaction we take into account the influence of charged dust of cometary coma on bow shock formation. Our description is performed on the basis of a self-consistent model which takes into account solar radiation; dust particle charging; evaporation and formation of neutral particles; photoionization; electric fields; the evolution of solar wind ions, cometary ions and dust particles; as well as the dust charge variation. It is shown that the presence of dust in cometary coma can modify shock wave formed as a result of Solar wind interaction with a comet. The outer shock wave (bow shock) can be considered as an ion acoustic shock wave modified by dust particle charging process. Possible formation of dust structures in the region of the interaction of Solar wind with cometary coma is discussed. The developed model allows us to determine the shock front structure. The calculations are performed for a comet situated at the distance of 1 AU from the Sun. For typical cometary nucleus size of about 1 km and rather dense dusty coma (exceeding million of cubic centimeters near the comet nucleus) the bow shock formed as a result of the interaction of Solar wind with the coma is expected to be related to the anomalous dissipation due to the dust particle charging. The bow shock is similar, by its origin, to the shocks observed by Nakamura et al. (Phys. Rev. Lett. 83, 1602 (1999)) and Luo et al. (Phys. Plasmas 6, 3455 (1999)) and those predicted theoretically (Popel et al., Phys. Plasmas 3, 4313 (1996); Popel et al., Phys. Plasmas 7, 2410 (2000)).

  17. Coronal Plumes in the Fast Solar Wind

    NASA Technical Reports Server (NTRS)

    Velli, Marco; Lionello, Roberto; Linker, Jon A.; Mikic, Zoran

    2011-01-01

    The expansion of a coronal hole filled with a discrete number of higher density coronal plumes is simulated using a time-dependent two-dimensional code. A solar wind model including an exponential coronal heating function and a flux of Alfven waves propagating both inside and outside the structures is taken as a basic state. Different plasma plume profiles are obtained by using different scale heights for the heating rates. Remote sensing and solar wind in situ observations are used to constrain the parameter range of the study. Time dependence due to plume ignition and disappearance is also discussed. Velocity differences of the order of approximately 50 km/s, such as those found in microstreams in the high-speed solar wind, may be easily explained by slightly different heat deposition profiles in different plumes. Statistical pressure balance in the fast wind data may be masked by the large variety of body and surface waves which the higher density filaments may carry, so the absence of pressure balance in the microstreams should not rule out their interpretation as the extension of coronal plumes into interplanetary space. Mixing of plume-interplume material via the Kelvin-Helmholtz instability seems to be possible within the parameter ranges of the models defined here, only at large di stances from the Sun, beyond 0.2-0.3 AU. Plasma and composition measurements in the inner heliosphere, such as those which will become available with Solar Orbiter and Solar Probe Plus, should therefore definitely be able to identify plume remnants in the solar wind.

  18. Substorm occurrence during quiet solar wind driving

    NASA Astrophysics Data System (ADS)

    Pulkkinen, T. I.; Partamies, N.; Kilpua, E. K. J.

    2014-04-01

    We examine the OMNI database and International Monitor for Auroral Geomagnetic Effects (IMAGE) magnetometer chain records to study the substorm occurrence and characteristics during quiet solar driving periods, especially during the solar minimum period in 2009. We define substorm-like activations as periods where the hourly average AL is below -200 nT. Using the OMNI data set, we demonstrate that there are limiting solar wind speed, interplanetary magnetic field magnitude, and driving electric field values below which substorm-like activations (AL < 200 nT, intensification and decay of the electrojet) do not occur. These minimum parameter values are V < 266 km/s, B < 1.4 nT, and E < 0.025 mV/m such low values are observed less than 1% of the time. We also show that for the same level of driving solar wind electric field, the electrojet intensity is smaller (by few tens of nT), and the electrojet resides farther poleward (by over 1°) during extended quiet solar driving in 2009 than during average solar activity conditions. During the solar minimum period in 2009, we demonstrate that substorm-like activations can be identified from the IMAGE magnetometer chain observations during periods when the hourly average IL index is below -100 nT. When the hourly IL activity is smaller than that, which covers 87% of the nighttime observations, the electrojet does not show coherent behavior. We thus conclude that substorm recurrence time during very quiet solar wind driving conditions is about 5-8 h, which is almost double that of the average solar activity conditions.

  19. Solar cycle changes in the polar solar wind

    NASA Technical Reports Server (NTRS)

    Coles, W. A.; Rickett, B. J.; Rumsey, V. H.; Kaufman, J. J.; Turley, D. G.; Ananthakrishnan, S.; Armstrong, J. W.; Harmons, J. K.; Scott, S. L.; Sime, D. G.

    1980-01-01

    It is noted that although the 11 year solar cycle was first recognized in 1843, it is still only poorly understood. Further, while there are satisfactory models for the magnetic variations, the underlying physics is still obscure. New observations on the changing three-dimensional form of the solar wind are presented which help relate some of the modulations observed in geomagnetic activity, the ionosphere, and the flux of galactic cosmic rays.

  20. Combined Solar and Wind Energy Systems

    NASA Astrophysics Data System (ADS)

    Tripanagnostopoulos, Y.; Souliotis, M.; Makris, Th.

    2010-01-01

    In this paper we present the new concept of combined solar and wind energy systems for buildings applications. Photovoltaics (PV) and small wind turbines (WTs) can be install on buildings, in case of sufficient wind potential, providing the building with electricity. PVs can be combined with thermal collectors to form the hybrid photovoltaic/thermal (PV/T) systems. The PVs (or the PV/Ts) and WT subsystems can supplement each other to cover building electrical load. In case of using PV/T collectors, the surplus of electricity, if not used or stored in batteries, can increase the temperature of the thermal storage tank of the solar thermal unit. The description of the experimental set-up of the suggested PV/T/WT system and experimental results are presented. In PV/T/WT systems the output from the solar part depends on the sunshine time and the output of the wind turbine part depends on the wind speed and is obtained any time of day or night. The use of the three subsystems can cover a great part of building energy load, contributing to conventional energy saving and environment protection. The PV/T/WT systems are considered suitable in rural and remote areas with electricity supply from stand-alone units or mini-grid connection. PV/T/WT systems can also be used in typical grid connected applications.

  1. Solar Wind Drivers for Steady Magnetospheric Convection

    NASA Technical Reports Server (NTRS)

    McPherron, Robert L.; O'Brien, T. Paul; Thompson, Scott; Lui, A. T. Y. (Editor)

    2005-01-01

    Steady magnetospheric convection (SMC) also known as convection bays, is a particular mode of response of the magnetosphere to solar wind coupling. It is characterized by convection lasting for times longer than a typical substorm recovery during which no substorms expansions can be identified. It is generally believed that the solar wind must be unusually steady for the magnetosphere to enter this state. However, most previous studies have assumed this is true and have used such conditions to identify events. In a preliminary investigation using only the AE and AL indices to select events we have shown that these expectations are generally correct. SMC events seem to be associated with slow speed solar wind and moderate, stable IMF Bz. In this report we extend our previous study including additional parameters and the time variations in various statistical quantities. For the intervals identified as SMCs we perform a detailed statistical analysis of the properties of different solar wind variables. We compare these statistics to those determined from all data, and from intervals in which substorms but not SMCs are present. We also consider the question of whether substorms are required to initiate and terminate an SMC. We conclude that the intervals we have identified as SMC are likely to be examples of the original Dungey concept of balanced reconnection at a pair of x-lines on the day and night side of the Earth.

  2. Electrodynamic sailing - Beating into the solar wind.

    NASA Technical Reports Server (NTRS)

    Sonett, C. P.; Fahleson, U.; Alfven, H.

    1972-01-01

    The recent suggestion by Alfven (1972) of a novel means of spacecraft propulsion based upon energy extraction from the electromagnetic field of the solar wind is critically reviewed. In response to this review, the original suggestion is somewhat amplified and clarified by its author.

  3. Solar Wind and Motion of Meteoroids

    E-print Network

    Jozef Klacka

    1999-10-04

    The effect of nonradial component of solar wind is discussed from the qualitative point of view. It is shown that the direction of nonradial component is opposite in comparison with the direction used in papers dealing with orbital evolution of meteoroids.

  4. Energy Primer: Solar, Water, Wind, and Biofuels.

    ERIC Educational Resources Information Center

    Portola Inst., Inc., Menlo Park, CA.

    This is a comprehensive, fairly technical book about renewable forms of energy--solar, water, wind, and biofuels. The biofuels section covers biomass energy, agriculture, aquaculture, alcohol, methane, and wood. The focus is on small-scale systems which can be applied to the needs of the individual, small group, or community. More than one-fourth…

  5. The energy balance of the solar wind

    NASA Technical Reports Server (NTRS)

    Hollweg, J. V.

    1981-01-01

    The effects of modifying some of the 'classical' assumptions underlying many of the solar wind models constructed over the past 20 years are examined in an effort to obtain both a better fit with the observations and a deeper understanding of the relevant physical processes.

  6. Identifying Wind and Solar Ramping Events: Preprint

    SciTech Connect

    Florita, A.; Hodge, B. M.; Orwig, K.

    2013-01-01

    Wind and solar power are playing an increasing role in the electrical grid, but their inherent power variability can augment uncertainties in power system operations. One solution to help mitigate the impacts and provide more flexibility is enhanced wind and solar power forecasting; however, its relative utility is also uncertain. Within the variability of solar and wind power, repercussions from large ramping events are of primary concern. At the same time, there is no clear definition of what constitutes a ramping event, with various criteria used in different operational areas. Here the Swinging Door Algorithm, originally used for data compression in trend logging, is applied to identify variable generation ramping events from historic operational data. The identification of ramps in a simple and automated fashion is a critical task that feeds into a larger work of 1) defining novel metrics for wind and solar power forecasting that attempt to capture the true impact of forecast errors on system operations and economics, and 2) informing various power system models in a data-driven manner for superior exploratory simulation research. Both allow inference on sensitivities and meaningful correlations, as well as the ability to quantify the value of probabilistic approaches for future use in practice.

  7. Magnetospheric responses to sudden and quasiperiodic solar wind variations

    E-print Network

    California at Berkeley, University of

    Magnetospheric responses to sudden and quasiperiodic solar wind variations K.-H. Kim,1 C. A.e., magnetosphere, magnetosheath, and solar wind) because of the solar wind dynamic pressure variations and its high into the magnetosphere, the lower-latitude data on the nightside are important to monitor the external source variations

  8. Evidence for Langmuir wave tunneling in the inhomogeneous solar wind

    E-print Network

    California at Berkeley, University of

    Evidence for Langmuir wave tunneling in the inhomogeneous solar wind A. J. Willes School of Physics antennas in Earth's foreshock and the solar wind have been interpreted as beating associated with large scattered to low wave numbers in the inhomogeneous solar wind. An alternative interpretation, investigated

  9. Measuring the Isotopic Composition of Solar Wind Noble Gases

    E-print Network

    Floss, Christine

    5 Measuring the Isotopic Composition of Solar Wind Noble Gases Alex Meshik, Charles Hohenberg, Olga and processes leading to the variations observed and how the present solar wind noble gases may differ from and breccias, implanted with solar wind noble gases, did provide a needed ground truth, neither by themselves

  10. Ion Cyclotron Waves (ICWs) in the Solar Wind

    E-print Network

    Strangeway, Robert J.

    Ion Cyclotron Waves (ICWs) in the Solar Wind of the Inner Heliosphere Lan K. Jian1,2 1Dept;History of the Study · In 2008, before I graduated, when I was studying the solar wind magnetic field data in various planetary environment. I found the characteristics of these waves in the solar wind mimicked

  11. Magnetospheric cavity modes driven by solar wind dynamic pressure fluctuations

    E-print Network

    Lotko, William

    Magnetospheric cavity modes driven by solar wind dynamic pressure fluctuations S. G. Claudepierre,1-dimensional magnetohydrodynamic (MHD) simulations of the solar wind-magnetosphere interaction. We use these simulations to investigate the role that solar wind dynamic pressure fluctuations play in the generation of magnetospheric

  12. Anisotropic MHD Turbulence in the Interstellar Medium and Solar Wind

    E-print Network

    Ng, Chung-Sang

    Anisotropic MHD Turbulence in the Interstellar Medium and Solar Wind C. S. Ng Center for Magnetic (MHD) turbulence Observations in ISM and solar wind · Anisotropy due to magnetic field · Electron MHD density spectrum and spatial scales wave number density Kolmogorov law #12;Solar wind turbulence From

  13. Turbulent heating of the corona and solar wind: the heliospheric

    E-print Network

    Turbulent heating of the corona and solar wind: the heliospheric dark energy problem Stuart D. Bale that the gas is highly ionized, i.e. a magnetized collisionless plasma ( solar wind model A `solar wind' is accelerated from the corona - Hydrostatic solution (similar to Bondi accretion

  14. PROPAGATION AND EVOLUTION OF ICMES IN THE SOLAR WIND

    E-print Network

    California at Berkeley, University of

    evolve in the solar wind. For the shorter-term, 30-60 minute forecasting based on L1 observa- tionsPROPAGATION AND EVOLUTION OF ICMES IN THE SOLAR WIND John D. Richardson, Ying Liu, and John W. Two characteristics present in some ICMEs but generally not present in the ambient solar wind, high

  15. Apollo 11 solar wind composition experiment: first results.

    PubMed

    Bühler, F; Eberhardt, P; Geiss, J; Meister, J; Signer, P

    1969-12-19

    The helium-4 solar wind flux during the Apollo 11 lunar surface excursion was (6.3 +/- 1.2) x 10(6) atoms per square centimeter per second. The solar wind direction and energy are essentially not perturbed by the moon. Evidence for a lunar solar wind albedo was found. PMID:17742848

  16. Material Interactions with Solar Wind Ion Environments

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.; McWilliams, Brett

    2006-01-01

    Solar wind composition is dominated by hydrogen (approx.96%) and helium (approx.3 to 4%) with a minor fraction (less than or equal to 1%) of heavy ions. Hydrogen (helium) ions impact spacecraft surfaces with energies from 0.5 to 5 keV (1.8 to 21 keV) due to variations in solar wind velocity from 300 km/s to 1000 km/sec with extremes of a few 10 s keV during periods of extremely high solar wind velocity exceeding 1000 km/sec. Mean impact energies are typically on the order of approximately 1 keV and 4 keV for hydrogen ions and helium ions, respectively. These energies are typically of the peak of the energy dependent light ion sputter yields for hydrogen and helium on many metals. In addition, light ions with kilovolt energies have been shown to produce blister (or exfoliation) damage to metal surfaces due to formation of high pressure gas bubbles within the materials when exposed to ion fluences on the order of 10(exp 16 to (10(exp 17 ions/sq cm. A number of spacecraft designs for current and future missions include gossamer polymer structures with thin metallic reflection coatings to shield instruments from the Sun or solar sail propulsion systems for use in a variety of locations in the inner solar system from 0.5 to 1 AU. In addition, there is interest in designing spacecraft for solar physics missions requiring operations as close to the Sun as 0.16 to 0.2 AU. Integrity of the metallic coatings is critical in many of these applications since degradation will result in modification of material thermal properties or exposure of polymers to solar UV photons which can compromise mission requirements. This paper will evaluate the relative contributions of sputtering and blister formation to material degradation in solar wind environments over a range of radial distances from the Sun to demonstrate where solar wind environments become important for materials selection. We will first review the physics and results from laboratory measurements of light ion sputtering, blistering, and exfoliation of metallic surfaces to establish the order of magnitude ion fluence required for significant surface damage. Solar wind ion fluence environments will then be evaluated due to variations in solar wind conditions as a function of solar cycle for varying distances from the Sun using models for radial variations in solar wind ion number density, temperature, and velocity to determine where sputtering and blistering is most likely to be an issue. Finally, ion fluence statistics for varying radial distances from the Sun will be shown to establish the mission duration and radial distances from the Sun where missions will encounter sufficient ion fluence to exhibit damage to metallic surfaces.

  17. Relative abundance of 3He(++) in the solar wind

    SciTech Connect

    Coplan, M.A.; Ogilvie, K.W.; Bochsler, P.

    1983-11-01

    Continuous measurements of solar wind 3He(++) and 4He(++) were made covering a full range of solar wind conditions. The average flux ratio derived from these data is 2310 + or - 50, in excellent agreement with the Apollo foil measurements. A probable correlation between average flux ratio and solar activity was found however, an examination of the data during periods of 3He(++)-rich solar flares shows no detectable increase in 3He(++) in the solar wind.

  18. The Genesis Mission: Solar Wind Conditions, and Implications for the FIP Fractionation of the Solar Wind.

    SciTech Connect

    Reisenfeld, D. B.; Wiens, R. C.; Barraclough, B. L.; Steinberg, J. T; Dekoning, C. A.; Zurbuchen, T. H.; Burnett, D. S.

    2005-01-01

    The NASA Genesis mission collected solar wind on ultrapure materials between November 30, 2001 and April 1, 2004. The samples were returned to Earth September 8, 2004. Despite the hard landing that resulted from a failure of the avionics to deploy the parachute, many samples were returned in a condition that will permit analyses. Sample analyses of these samples should give a far better understanding of the solar elemental and isotopic composition (Burnett et al. 2003). Further, the photospheric composition is thought to be representative of the solar nebula, so that the Genesis mission will provide a new baseline for the average solar nebula composition with which to compare present-day compositions of planets, meteorites, and asteroids. Sample analysis is currently underway. The Genesis samples must be placed in the context of the solar and solar wind conditions under which they were collected. Solar wind is fractionated from the photosphere by the forces that accelerate the ions off of the Sun. This fractionation appears to be ordered by the first ionization potential (FIP) of the elements, with the tendency for low-FIP elements to be over-abundant in the solar wind relative to the photosphere, and high-FIP elements to be under-abundant (e.g. Geiss, 1982; von Steiger et al., 2000). In addition, the extent of elemental fractionation differs across different solarwind regimes. Therefore, Genesis collected solar wind samples sorted into three regimes: 'fast wind' or 'coronal hole' (CH), 'slow wind' or 'interstream' (IS), and 'coronal mass ejection' (CME). To carry this out, plasma ion and electron spectrometers (Barraclough et al., 2003) continuously monitored the solar wind proton density, velocity, temperature, the alpha/proton ratio, and angular distribution of suprathermal electrons, and those parameters were in turn used in a rule-based algorithm that assigned the most probable solar wind regime (Neugebauer et al., 2003). At any given time, only one of three regime-specific collectors (CH, IS, or CME) was exposed to the solar wind. Here we report on the regime-specific solar wind conditions from in-situ instruments over the course of the collection period. Further, we use composition data from the SWICS (Solar Wind Ion Composition Spectrometer) instrument on ACE (McComas et al., 1998) to examine the FIP fractionation between solar wind regimes, and make a preliminary comparison of these to the FIP analysis of Ulysses/SWICS composition data (von Steiger et al. 2000). Our elemental fractionation study includes a reevaluation of the Ulysses FIP analysis in light of newly reported photospheric abundance data (Asplund, Grevesse & Sauval, 2005). The new abundance data indicate a metallicity (Z/X) for the Sun almost a factor of two lower than that reported in the widely used compilation of Anders & Grevesse (1989). The new photospheric abundances suggest a lower degree of solar wind fractionation than previously reported by von Steiger et al. (2000) for the first Ulysses polar orbit (1991-1998).

  19. Wind and IMP 8 Solar Wind, Magnetosheath and Shock Data

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The purpose of this project was to provide the community access to magnetosheath data near Earth. We provided 27 years of IMP 8 magnetosheath proton velocities, densities, and temperatures with our best (usually 1-min.) time resolution. IMP 8 crosses the magnetosheath twice each 125 day orbit, and we provided magnetosheath data for the roughly 27 years of data for which magnetometer data are also available (which are needed to reliably pick boundaries). We provided this 27 years of IMP 8 magnetosheath data to the NSSDC; this data is now integrated with the IMP 8 solar wind data with flags indicating whether each data point is in the solar wind, magnetosheath, or at the boundary between the two regions. The plasma speed, density, and temperature are provided for each magnetosheath point. These data are also available on the MIT web site ftp://space .mit.edu/pub/plasma/imp/www/imp.html. We provide ASCII time-ordered rows of data giving the observation time, the spacecraft position in GSE, the velocity is GSE, the density and temperature for protons. We also have analyzed and archived on our web site the Wind magnetosheath plasma parameters. These consist of ascii files of the proton and alpha densities, speeds, and thermal speeds. These data are available at ftp://space.mit.edu/pub/plasma/wind/sheath These are the two products promised in the work statement and they have been completed in full.

  20. Solar Wind Ablation of Terrestrial Planet Atmospheres

    NASA Technical Reports Server (NTRS)

    Moore, Thomas Earle; Fok, Mei-Ching H.; Delcourt, Dominique C.

    2009-01-01

    Internal plasma sources usually arise in planetary magnetospheres as a product of stellar ablation processes. With the ignition of a new star and the onset of its ultraviolet and stellar wind emissions, much of the volatiles in the stellar system undergo a phase transition from gas to plasma. Condensation and accretion into a disk is replaced by radiation and stellar wind ablation of volatile materials from the system- Planets or smaller bodies that harbor intrinsic magnetic fields develop an apparent shield against direct stellar wind impact, but UV radiation still ionizes their gas phases, and the resulting internal plasmas serve to conduct currents to and from the central body along reconnected magnetic field linkages. Photoionization and thermalization of electrons warms the ionospheric topside, enhancing Jeans' escape of super-thermal particles, with ambipolar diffusion and acceleration. Moreover, observations and simulations of auroral processes at Earth indicate that solar wind energy dissipation is concentrated by the geomagnetic field by a factor of 10-100, enhancing heavy species plasma and gas escape from gravity, and providing more current carrying capacity. Thus internal plasmas enable coupling with the plasma, neutral gas and by extension, the entire body. The stellar wind is locally loaded and slowed to develop the required power. The internal source plasma is accelerated and heated, inflating the magnetosphere as it seeks escape, and is ultimately blown away in the stellar wind. Bodies with little sensible atmosphere may still produce an exosphere of sputtered matter when exposed to direct solar wind impact. Bodies with a magnetosphere and internal sources of plasma interact more strongly with the stellar wind owing to the magnetic linkage between the two created by reconnection.

  1. On Solar-Wind Electron Heating at Large Solar Distances

    NASA Astrophysics Data System (ADS)

    Chashei, Igor V.; Fahr, Hans J.

    2014-04-01

    We study the temperature of electrons advected with the solar wind to large solar distances far beyond 1 AU. Almost nothing is known about the thermodynamics of these electrons from in-situ plasma observations at these distances, and usually it is tacitly assumed that electrons, due to adiabatic behaviour and vanishing heat conduction, rapidly cool off to very low temperatures at larger distances. In this article we show, however, that electrons on their way to large distances undergo non-adiabatic interactions with travelling shocks and solar-wind bulk-velocity jumps and thereby are appreciably heated. Examining this heating process on an average statistical basis, we find that solar-wind electrons first cool down to a temperature minimum, which depending on the occurrence frequency of bulk velocity jumps is located between 3 and 6 AU, but beyond this the lowest electron temperature again starts to increase with increasing solar distance, finally achieving temperatures of about 7×104 K to 7×105 K at the location of the termination shock. Hence these electrons are unexpectedly shown to play an important dynamical role in structuring this shock and in determining the downstream plasma properties.

  2. Solar sources of the interplanetary magnetic field and solar wind

    NASA Technical Reports Server (NTRS)

    Levine, R. H.; Altschuler, M. D.; Harvey, J. W.

    1977-01-01

    Open magnetic field lines, those which extend from the solar photosphere to interplanetary space, are traced in the current-free (potential field) approximation using measured photospheric fields as a boundary condition. It is found that (1) only a relatively small fraction of the photospheric area connects via open field lines to the interplanetary magnetic field; (2) those photospheric areas which do contribute open field lines lie beneath coronal holes and within the boundaries of the holes as projected onto the photosphere or else between loop systems of an active region; (3) the interplanetary magnetic field in the plane of the sun's equator, essentially the field in the ecliptic plane, may connect to photospheric regions of high latitude; and (4) the fastest solar wind streams are correlated with those magnetic flux tubes which expand least in cross-sectional area over the distance between the photosphere and the coronal height where the solar wind begins.

  3. Laboratory experiments simulating solar wind driven magnetospheres

    SciTech Connect

    Brady, P.; Ditmire, T.; Horton, W.; Mays, M. L.; Zakharov, Y.

    2009-04-15

    Magnetosphere-solar wind interactions are simulated in a laboratory setting with a small permanent magnet driven by two types of supersonic plasma wind sources. The first higher speed, shorter duration plasma wind is from a laser blow-off plasma while the second longer duration, lower speed plasma wind is produced with a capacitor discharge driven coaxial electrode creating plasma jets. The stand off distance of the solar wind from the magnetosphere was measured to be 1.7{+-}0.3 cm for the laser-produced plasma experiment and 0.87{+-}0.03 cm for the coaxial electrode plasma experiment. The stand off distance of the plasma was calculated using data from HYADES[J. T. Larsen and S. M. Lane, J. Quant. Spectrosc. Radiat. Transf. 51, 179 (1994)] as 1.46{+-}0.02 cm for the laser-produced plasma, and estimated for the coaxial plasma jet as r{sub mp}=0.72{+-}0.07 cm. Plasma build up on the poles of the magnets, consistent with magnetosphere systems, was also observed.

  4. Pluto's solar wind interaction: Collisional effects

    NASA Astrophysics Data System (ADS)

    Cravens, T. E.; Strobel, D. F.

    2015-01-01

    Exospheric neutral atoms and molecules (primarily N2, with trace amounts of CH4 and CO according to our current understanding of Pluto's atmosphere) escape from Pluto and travel into interplanetary space for millions of kilometers. Eventually, the neutrals are ionized by solar EUV photons and/or by collisions with solar wind electrons. The mass-loading associated with this ion pick-up is thought to produce a comet-like interaction of the solar wind with Pluto. Within a few thousand kilometers of Pluto the solar wind interaction should lead to a magnetic field pile-up and draping, as it does around other "non-magnetic" bodies such as Venus and comets. The structure of plasma regions and boundaries will be greatly affected by large gyroradii effects and the extensive exosphere. Energetic plasma should disappear from the flow within radial distances of a few thousand kilometers due to charge exchange collisions. An ionosphere should be present close to Pluto with a composition that is determined both by the primary ion production and ion-neutral chemistry. One question discussed in the paper is whether or not the ionosphere has a Venus-like sharply defined ionopause boundary or a diamagnetic cavity such as that found around comet Halley. Simple physical estimates of plasma processes and structures in the collision-dominated region are made in this paper and predictions are made for the New Horizons mission.

  5. The solar wind as deduced from lunar samples

    NASA Technical Reports Server (NTRS)

    Eberhardt, P.

    1974-01-01

    Lunar surface samples, which have been exposed to the solar wind, can be used to obtain information on the recent and past solar wind. Some of the more important conclusions reached are: The D/H ratio in the solar wind is smaller than 0.000003. The isotopic composition of C, Ar (except Ar-40), and Kr in the solar wind and on the earth are the same within approximately plus or minus 3%. Terrestrial Ne is enriched in the heavier isotopes relative to solar wind Ne. The average solar wind flux in the past was probably higher than at present. The average solar wind energy has varied in the past; however, no long time trend is apparent. Evidence for a secular decrease of the He-4/He-3 ratio with time exists.

  6. Characteristics of solar wind density depletions during solar cycles 23 and 24

    NASA Astrophysics Data System (ADS)

    Park, K.; Lee, J.; Oh, S.; Yi, Y.

    2014-12-01

    Solar wind density depletions are generally believed to be caused by the interplanetary (IP) shocks. However, there are other cases that are hardly associated with IP shocks. To better understand the cause of the density depletions, we investigate the solar wind parameters and interplanetary magnetic field (IMF) data related to the solar wind density depletion events during the period from 1996 to 2013 that are obtained with the Advanced Composition Explorer (ACE) and the WIND satellite. As a result, we found that the solar wind density has an anti-correlation with IMF strength during all events of solar wind density depletion, regardless of the presence of IP shocks. We thus argue that IMF strength is an important factor in understanding the nature of solar wind density depletion. Since IMF strength varies with solar cycle, we also investigate the characteristics of solar wind density depletion events in different phases of solar cycle as an attempt to find its connection to the sun.

  7. Lower hybrid waves in the solar wind

    NASA Technical Reports Server (NTRS)

    Marsch, E.; Chang, T.

    1982-01-01

    It is demonstrated that the frequently observed broad band low frequency electrostatic noise in the solar wind generally has a dominant lower hybrid component. These modes are probably produced by the anisotropic halos of the solar wind electron velocity distributions exhibiting 'heat flux' profiles and thus, are accompanied by broad band, 'hybrid-like' whistler waves. When the electron temperature is much larger than the ion temperature, these modes can also co-exist with the ion acoustic waves. Since lower hybrid modes propagate nearly normal to the interplanetary magnetic field lines, the ions can be transversely accelerated by these waves and attain the observed anisotropic and/or loss-cone-like distributions.

  8. The solar wind and magnetospheric dynamics

    NASA Technical Reports Server (NTRS)

    Russell, C. T.

    1974-01-01

    The dynamic processes involved in the interaction between the solar wind and the earth's magnetosphere are reviewed. The evolution of models of the magnetosphere is first surveyed. The existence of the auroral substorm and the cyclical polar magnetic substorm is evidence that the magnetosphere is a dynamic system. The dynamic changes occurring in the magnetosphere, including erosion of the magnetopause, changes in the size of the polar cap, variations in the flaring angle of the tail, neutral point formation, plasma sheet motions, and the inward collapse of the midnight magnetosphere, are discussed. The cyclical variations of geomagnetic activity are explained in terms of the control of the solar wind-magnetosphere interaction by the north-south component of the interplanetary magnetic field. Present phenomenological models allow prediction of geomagnetic activity from interplanetary measurements, but modeling of detailed magnetospheric processes is still in its infancy.

  9. Deimos: an obstacle to the solar wind.

    PubMed

    Sauer, K; Dubinin, E; Baumgärtel, K; Bogdanov, A

    1995-08-25

    Two isolated solar wind disturbances about 5 minutes in duration were detected aboard the Russian spacecraft Phobos-2 upon its crossing the wake of the martian moon Deimos about 15,000 kilometers downstream from the moon on 1 February 1989. These plasma and magnetic events are interpreted as the inbound and outbound crossings of a Mach cone that is formed as a result of an effective interaction of the solar wind with Deimos. Possible mechanisms such as remanent magnetization, cometary type interaction caused by heavy ion or charged dust production, and unipolar induction resulting from the finite conductivity of the body are discussed. Although none of the present models is fully satisfactory, neutral gas emission through water loss by Deimos at a rate of about 10(23) molecules per second, combined with a charged dust coma, is favored. PMID:17755527

  10. Solar wind plasma interaction with Gerasimovich lunar magnetic anomaly

    NASA Astrophysics Data System (ADS)

    Fatemi, Shahab; Lue, Charles; Holmström, Mats; Poppe, Andrew R.; Wieser, Martin; Barabash, Stas; Delory, Gregory T.

    2015-06-01

    We present the results of the first local hybrid simulations (particle ions and fluid electrons) for the solar wind plasma interaction with realistic lunar crustal fields. We use a three-dimensional hybrid model of plasma and an empirical model of the Gerasimovich magnetic anomaly based on Lunar Prospector observations. We examine the effects of low and high solar wind dynamic pressures on this interaction when the Gerasimovich magnetic anomaly is located at nearly 20° solar zenith angle. We find that for low solar wind dynamic pressure, the crustal fields mostly deflect the solar wind plasma, form a plasma void at very close distances to the Moon (below 20 km above the surface), and reflect nearly 5% of the solar wind in charged form. In contrast, during high solar wind dynamic pressure, the crustal fields are more compressed, the solar wind is less deflected, and the lunar surface is less shielded from impinging solar wind flux, but the solar wind ion reflection is more locally intensified (up to 25%) compared to low dynamic pressures. The difference is associated with an electrostatic potential that forms over the Gerasimovich magnetic anomaly as well as the effects of solar wind plasma on the crustal fields during low and high dynamic pressures. Finally, we show that an antimoonward Hall electric field is the dominant electric field for ˜3 km altitude and higher, and an ambipolar electric field has a noticeable contribution to the electric field at close distances (<3 km) to the Moon.

  11. 76 FR 73783 - Residential, Business, and Wind and Solar Resource Leases on Indian Land

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-29

    ...covered by Subpart E (wind energy evaluation and wind and solar resource development...to harness wind and/or solar energy to generate and supply electricity...maintenance of wind and/or solar energy resource development...

  12. Solar Wind Electron Energization by Plasma Turbulence

    NASA Astrophysics Data System (ADS)

    Yoon, P. H.

    2015-09-01

    The solar wind electrons are made of the low-energy Maxwellian core, intermediate-energy halo, field-aligned strahl, and the highly-energetic super-halo electrons. The present paper discusses a model in which the halo electrons interact with the whistler fluctuation via cyclotron wave-particle resonance, and the super-halo electrons interact through Landau resonance with the Langmuir fluctuation, thus maintaining a local steady state.

  13. Turbulence and waves in the solar wind

    SciTech Connect

    Roberts, D.A.; Goldstein, M.L. )

    1991-01-01

    Studies of turbulence and waves in the solar wind is discussed. Consideration is given to the observations and theory concerning the origin and evolution of interplanetary MHD fluctuations and to the observations, theory, and simulations of compressive fluctuations. Particular attention is given to extrapolations to near-sun and polar fields regions. Results obtained on turbulence at comets and magnetic turbulence of low-frequency waves excited by unstable distributions of ions are discussed. 230 refs.

  14. Cometary ion instabilities in the solar wind

    NASA Astrophysics Data System (ADS)

    Matteini, L.; Schwartz, S. J.; Hellinger, P.

    2015-12-01

    We review some of the processes that characterize the interaction of the solar wind with newborn cometary ions. Instabilities generated by the typical ring-beam velocity-space configuration of the pick-up ions in the solar wind frame are studied by means of one- and two-dimensional hybrid numerical simulations. In agreement with previous studies, we find that instabilities generated by the cometary ions play an important role in shaping the properties of the plasma. The resulting ion distributions are in good agreement with observations, showing the presence of energy shells in velocity space. Bi-spherical shells for the heavy oxygen ions are also observed in the late phase of the simulations. Moreover, we also investigate some new aspects of the dynamics, such as the generation of turbulent cascade from the initial spectra of unstable waves, and the related heating and back reaction of the solar wind plasma. We also consider the case of initial non-gyrotropic pick-up ion distributions, and we focus on the polarization of the associated waves, suggesting that linear polarization can be a signature of this configuration, possibly observed by the Rosetta spacecraft in orbit around comet 67P/CG.

  15. Solar Wind Charge Exchange During Geomagnetic Storms

    NASA Technical Reports Server (NTRS)

    Robertson, Ina P.; Cravens, Thomas E.; Sibeck, David G.; Collier, Michael R.; Kuntz, K. D.

    2012-01-01

    On March 31st. 2001, a coronal mass ejection pushed the subsolar magnetopause to the vicinity of geosynchronous orbit at 6.6 RE. The NASA/GSFC Community Coordinated Modeling Center (CCMe) employed a global magnetohydrodynamic (MHD) model to simulate the solar wind-magnetosphere interaction during the peak of this geomagnetic storm. Robertson et aL then modeled the expected 50ft X-ray emission due to solar wind charge exchange with geocoronal neutrals in the dayside cusp and magnetosheath. The locations of the bow shock, magnetopause and cusps were clearly evident in their simulations. Another geomagnetic storm took place on July 14, 2000 (Bastille Day). We again modeled X-ray emission due to solar wind charge exchange, but this time as observed from a moving spacecraft. This paper discusses the impact of spacecraft location on observed X-ray emission and the degree to which the locations of the bow shock and magnetopause can be detected in images.

  16. Solar Wind Associated with Near Equatorial Coronal Hole

    NASA Astrophysics Data System (ADS)

    Hegde, M.; Hiremath, K. M.; Doddamani, Vijayakumar H.; Gurumath, Shashanka R.

    2015-09-01

    Present study probes temporal changes in the area and radiative flux of near equatorial coronal hole associated with solar wind parameters such as wind speed, density, magnetic field and temperature. Using high temporal resolution data from SDO/AIA for the two wavelengths 193 Å and 211 Å, area and radiative flux of coronal holes are extracted and are examined for the association with high speed solar wind parameters. We find a strong association between different parameters of coronal hole and solar wind. For both the wavelength bands, we also compute coronal hole radiative energy near the earth and it is found to be of similar order as that of solar wind energy. However, for the wavelength 193 Å, owing to almost similar magnitudes of energy emitted by coronal hole and energy due to solar wind, it is conjectured that solar wind might have originated around the same height where 193 Å line is formed in the corona.

  17. CHARGE STATE EVOLUTION IN THE SOLAR WIND. RADIATIVE LOSSES IN FAST SOLAR WIND PLASMAS

    SciTech Connect

    Landi, E.; Gruesbeck, J. R.; Lepri, S. T.; Zurbuchen, T. H.; Fisk, L. A.

    2012-10-10

    We study the effects of departures from equilibrium on the radiative losses of the accelerating fast, coronal hole-associated solar wind plasma. We calculate the evolution of the ionic charge states in the solar wind with the Michigan Ionization Code and use them to determine the radiative losses along the wind trajectory. We use the velocity, electron temperature, and electron density predicted by Cranmer et al. as a benchmark case even though our approach and conclusions are more broadly valid. We compare non-equilibrium radiative losses to values calculated assuming ionization equilibrium at the local temperature, and we find that differences are smaller than 20% in the corona but reach a factor of three in the upper chromosphere and transition region. Non-equilibrium radiative losses are systematically larger than the equilibrium values, so that non-equilibrium wind plasma radiates more efficiently in the transition region. Comparing the magnitude of the dominant energy terms in the Cranmer et al. model, we find that wind-induced departures from equilibrium are of the same magnitude as the differences between radiative losses and conduction in the energy equation. We investigate which ions are most responsible for such effects, finding that carbon and oxygen are the main source of departures from equilibrium. We conclude that non-equilibrium effects on the wind energy equation are significant and recommend that they are included in theoretical models of the solar wind, at least for carbon and oxygen.

  18. Western Wind and Solar Integration Study (Fact Sheet)

    SciTech Connect

    Not Available

    2012-09-01

    Initiated in 2007 to examine the operational impact of up to 35% penetration of wind, photovoltaic (PV), and concentrating solar power (CSP) energy on the electric power system, the Western Wind and Solar Integration Study (WWSIS) is one of the largest regional wind and solar integration studies to date. The goal is to understand the effects of variability and uncertainty of wind, PV, and CSP on the grid. In the Western Wind and Solar Integration Study Phase 1, solar penetration was limited to 5%. Utility-scale PV was not included because of limited capability to model sub-hourly, utility-scale PV output . New techniques allow the Western Wind and Solar Integration Study Phase 2 to include high penetrations of solar - not only CSP and rooftop PV but also utility-scale PV plants.

  19. Solar wind effects on atmosphere evolution at Venus and Mars

    NASA Technical Reports Server (NTRS)

    Luhmann, Janet G.; Bauer, S. J.

    1992-01-01

    The weak intrinsic magnetism of Venus and Mars leaves these planets subject to some unique atmospheric loss processes. This paper reviews the ways in which material seems to be removed by the solar wind interaction, including atmospheric ion pickup by the solar wind, bulk removal and outflow of ionospheric plasma, and atmospheric sputtering by pickup ions. The factors in the planets' and sun's histories, such as planetary magnetism, solar luminosity, and past solar wind properties, that must ultimately be folded into considerations of the effects of the solar wind interaction on atmosphere evolution are discussed.

  20. Magnetic Influences on the Solar Wind

    NASA Astrophysics Data System (ADS)

    Woolsey, Lauren N.

    2016-01-01

    The Sun is our closest star, and even with the ability to resolve fine structure, there are several large mysteries that remain unsolved. One of these unanswered questions is how the supersonic outflow from the Sun, the solar wind, is generated and accelerated. In this dissertation, I have investigated the role of Alfvén waves in heating the corona and accelerating the wind. I focus on modeling of flux tubes that are open to the heliosphere, i.e. bundles of magnetic field that stretch beyond a few solar radii into the heliosphere. In these flux tubes, Alfvén waves are launched by the shaking of the footpoints from the convective motions of granulation on the solar photosphere. I present results of modeling efforts in one dimension that investigate how this process changes for a variety of different magnetic field structures over a solar cycle and three-dimensional modeling of time-dependent processes that unlock a connection between pico- and nanoflare-scale events and the turbulent heating generated by counter-propagating Alfvén waves. In addition to computational modeling, I also present efforts to find magnetic thresholds in observations of small-scale network jets seen with the Interface Region Imaging Spectrograph (IRIS). These jets were first discovered by IRIS due to their short lifetimes (10s of seconds) and small size (widths of 100s of kilometers). The findings for this project suggest that the modeled Alfvén-wave-driven turbulence is consistent with these network jets.

  1. Electron energy flux in the solar wind.

    NASA Technical Reports Server (NTRS)

    Ogilvie, K. W.; Scudder, J. D.; Sugiura, M.

    1971-01-01

    Description of studies of electrons between 10 eV and 9.9 keV in the solar wind. The transport of energy in the rest frame of the plasma is evaluated and shown to be parallel to the interplanetary magnetic field. The presence of electrons from solar events causes this energy-flux density to exceed the heat flow due to thermal electrons. In one such event, the observations are shown to be consistent with the solar-electron observations made at higher energies. When observations are made at a point connected to the earth's bow shock by an interplanetary-field line, a comparatively large energy flux along the field toward the sun is observed, but the heat flow remains outwardly directed during this time interval. In either situation the heat flow is found to be consistent with measurements made on Vela satellites by a different method. These values, less than .01 ergs/sq cm/sec, are sufficiently low to require modifications to the Spitzer-Harm conductivity formula for use in solar-wind theories.

  2. The acceleration of the solar wind

    SciTech Connect

    Axford, W. I.; McKenzie, J. F.

    1996-07-20

    We review the observed properties of the solar wind with the aim of finding a simple and straightforward understanding of its origin and acceleration. A theory is developed for the high speed solar wind based on a simple dissipation length assumption for hydromagnetic wave heating of the coronal plasma close to the Sun. Solutions with the correct particle and energy fluxes and with a realistic magnetic field, match the requirements on the density at the base of the corona provided the dissipation length is relatively small ({approx}0.25-0.5 solar radii). The significant features are that the acceleration is rapid, with the sonic point within {approx}2 solar radii, and the proton temperatures are high, namely 8-10x10{sup 6} K. Such efficient dissipation requires any Alfven waves responsible to have frequencies in the range 0.01 Hz-10 kHz. This has implications for the nature of the plasma and energy source in the supergranular network.

  3. 15/06/2005 Solar Wind 11/SOHO 16 1 Radial Dependence of Solar

    E-print Network

    Kallenrode, May-Britt

    ;15/06/2005 Solar Wind 11/SOHO 16 4 Overview: spatial domain Long-term missions: At 1 AU: IMP, GOES, SOHO, Wind, ACE15/06/2005 Solar Wind 11/SOHO 16 1 Radial Dependence of Solar Energetic Particle Events M.-B. Kallenrode #12;15/06/2005 Solar Wind 11/SOHO 16 2 Outline No discussion about composition and charge states

  4. Solar wind interaction with the terrestrial planets

    NASA Astrophysics Data System (ADS)

    Garnier, Philippe; Milillo, Anna; Radioti, Aikaterini

    2015-09-01

    This issue entitled "Solar wind interaction with the terrestrial planets" follows the recurrent session PS5.1 (Planetary Plasma Physics and Interactions in the Solar System) held at the European Geophysical Union conference. The EGU session hosts original studies on all aspects of planetary plasma physics and interactions in the Solar System. This issue more specifically includes studies presented at several international meetings during the recent years on the physics of magnetospheres, ionospheres, auroras, and also the surface-plasma or atmosphere-plasma interactions, at inner planets such as Mercury, Earth (and Moon), Mars and Venus. The following papers, in fact, cover all of these aspects, and are based on a variety of techniques: space and ground-based observations, numerical modeling and even laboratory measurements.

  5. A Semiempirical Magnetohydrodynamical Model of the Solar Wind

    NASA Astrophysics Data System (ADS)

    Cohen, O.; Sokolov, I. V.; Roussev, I. I.; Arge, C. N.; Manchester, W. B.; Gombosi, T. I.; Frazin, R. A.; Park, H.; Butala, M. D.; Kamalabadi, F.; Velli, M.

    2007-01-01

    We present a new MHD model for simulating the large-scale structure of the solar corona and solar wind under ``steady state'' conditions stemming from the Wang-Sheeley-Arge empirical model. The processes of turbulent heating in the solar wind are parameterized using a phenomenological, thermodynamical model with a varied polytropic index. We employ the Bernoulli integral to bridge the asymptotic solar wind speed with the assumed distribution of the polytropic index on the solar surface. We successfully reproduce the mass flux from Sun to Earth, the temperature structure, and the large-scale structure of the magnetic field. We reproduce the solar wind speed bimodal structure in the inner heliosphere. However, the solar wind speed is in a quantitative agreement with observations at 1 AU for solar maximum conditions only. The magnetic field comparison demonstrates that the input magnetogram needs to be multiplied by a scaling factor in order to obtain the correct magnitude at 1 AU.

  6. Dust in the Solar Wind

    NASA Astrophysics Data System (ADS)

    Kramer, Emily; Bauer, James; Mainzer, Amy; Grav, Tommy; Nugent, Carolyn; Sonnett, Sarah; Stevenson, Rachel

    2015-08-01

    As some of the most pristine objects in the Solar System, comets present an excellent opportunity to understand the mechanics and chemistry of the planetary formation era. By studying a large number of comets in different dynamical classes, we can better understand their ensemble properties.NEOWISE is the planetary-funded mission that uses data from the Wide-field Infrared Survey Explorer (WISE) spacecraft to detect and characterize moving objects. The WISE mission surveyed the sky in four infrared wavelength bands (3.4, 4.6, 12 and 22-microns) between January 2010 and February 2011, during which time over 160 comets were detected. Since the restart of the mission as NEOWISE in December 2013, over 60 additional comets have been observed in the shorter two wavelength channels. In both phases of the mission, a mix of both long-period comets and short-period comets were detected. Over half of the comets in the prime mission displayed a significant dust tail in the 12 and 22-micron (thermal emission) bands, showing a wide range of activity levels and dust morphology. In both the prime and restarted phases of the mission, extended dust structures were also detected for many of the comets in the 3.4 and 4.6-micron bands. For the comets that displayed a significant dust tail, we have estimated the sizes and ages of the particles using dynamical models based on the Finson-Probstein method. We will present updated modeling results, comparing the different comet populations.

  7. MARS GLOBAL SURVEYOR MEASUREMENTS OF THE MARTIAN SOLAR WIND INTERACTION

    E-print Network

    California at Berkeley, University of

    with a variety of solar system bodies, and has direct bearing on studies of the long-term evolutionMARS GLOBAL SURVEYOR MEASUREMENTS OF THE MARTIAN SOLAR WIND INTERACTION D. A. BRAIN University 8 August 2006; Accepted in final form 17 November 2006) Abstract. The solar wind at Mars interacts

  8. Solar wind turbulence as a driver of geomagnetic activity

    NASA Astrophysics Data System (ADS)

    Ugwu, Ernest Benjamin Ikechukwu; Okeke, Francisca Nneka; Ugonabo, Obiageli Josephine

    2015-04-01

    We carried out simultaneous analyses of interplanetary and geomagnetic datasets for the period of (solar Maunder) least (2009) and maximum (2002) solar activity to determine the nature of solar wind turbulence on geomagnetic activity using AE, ASY-D, and ASY-H indices. We determined the role played by Alfvénic fluctuations in the solar wind so as to find out the nature of the turbulence. Our analyses showed that solar wind turbulence play a role in geomagnetic processes at high latitudes during periods of low and high solar activity but does not have any effect at mid-low latitudes.

  9. Variations of the solar wind and solar cycle in the last 300 years

    NASA Technical Reports Server (NTRS)

    Feynman, J.; Silverman, S.

    1980-01-01

    The past history of the solar wind and solar cycle, inferred from records of geomagnetics and aurora, is examined. Records show that the solar wind apparently varied in a systematic manner throughout the period from 1770 to 1857 and that the period around 1810 resembled the 1901 minimum geomagnetic disturbance. Results show that the solar wind and hence the Sun changes on a time scale long compared to a solar cycle and short compared to the Maunder minimum. The inclusion of a study on the solar wind and solar cycle variations for the SCADM mission is discussed.

  10. ISOTOPIC MASS FRACTIONATION OF SOLAR WIND: EVIDENCE FROM FAST AND SLOW SOLAR WIND COLLECTED BY THE GENESIS MISSION

    SciTech Connect

    Heber, Veronika S.; Baur, Heinrich; Wieler, Rainer; Bochsler, Peter; McKeegan, Kevin D.; Neugebauer, Marcia; Reisenfeld, Daniel B.; Wiens, Roger C.

    2012-11-10

    NASA's Genesis space mission returned samples of solar wind collected over {approx}2.3 years. We present elemental and isotopic compositions of He, Ne, and Ar analyzed in diamond-like carbon targets from the slow and fast solar wind collectors to investigate isotopic fractionation processes during solar wind formation. The solar wind provides information on the isotopic composition for most volatile elements for the solar atmosphere, the bulk Sun and hence, on the solar nebula from which it formed 4.6 Ga ago. Our data reveal a heavy isotope depletion in the slow solar wind compared to the fast wind composition by 63.1 {+-} 2.1 per mille for He, 4.2 {+-} 0.5 per mille amu{sup -1} for Ne and 2.6 {+-} 0.5 per mille amu{sup -1} for Ar. The three Ne isotopes suggest that isotopic fractionation processes between fast and slow solar wind are mass dependent. The He/H ratios of the collected slow and fast solar wind samples are 0.0344 and 0.0406, respectively. The inefficient Coulomb drag model reproduces the measured isotopic fractionation between fast and slow wind. Therefore, we apply this model to infer the photospheric isotopic composition of He, Ne, and Ar from our solar wind data. We also compare the isotopic composition of oxygen and nitrogen measured in the solar wind with values of early solar system condensates, probably representing solar nebula composition. We interpret the differences between these samples as being due to isotopic fractionation during solar wind formation. For both elements, the magnitude and sign of the observed differences are in good agreement with the values predicted by the inefficient Coulomb drag model.

  11. Nitrogen in solar energetic particles: isotopically distinct from solar wind.

    PubMed

    Mathew, K J; Kerridge, J F; Marti, K

    1998-12-01

    Stepwise etching of lunar soil ilmenite grains reveals that the 15N/14N ratio of implanted nitrogen decreases with increasing implantation depth within the ilmenite grains, i.e., with increasing energy of implantation. These results show that N derived from solar energetic particles, NSEP, is enriched in the light isotope, 14N, relative to solar-wind nitrogen, NSW. This is in striking contrast to the neon isotopic record: NeSEP is depleted in the light isotope, 20Ne, relative to NeSW. These data suggest either distinct signatures in the respective solar source regions, or fractionation in the acceleration mechanism(s). However, the observed opposite fractionation trends for light N and Ne isotopes do not agree with model predictions. PMID:11542821

  12. Variations of Strahl Properties with Fast and Slow Solar Wind

    NASA Technical Reports Server (NTRS)

    Figueroa-Vinas, Adolfo; Goldstein, Melvyn L.; Gurgiolo, Chris

    2008-01-01

    The interplanetary solar wind electron velocity distribution function generally shows three different populations. Two of the components, the core and halo, have been the most intensively analyzed and modeled populations using different theoretical models. The third component, the strahl, is usually seen at higher energies, is confined in pitch-angle, is highly field-aligned and skew. This population has been more difficult to identify and to model in the solar wind. In this work we make use of the high angular, energy and time resolution and three-dimensional data of the Cluster/PEACE electron spectrometer to identify and analyze this component in the ambient solar wind during high and slow speed solar wind. The moment density and fluid velocity have been computed by a semi-numerical integration method. The variations of solar wind density and drift velocity with the general build solar wind speed could provide some insight into the source, origin, and evolution of the strahl.

  13. Interpretation of Solar Wind Ion Composition Measurements from Ulysses

    NASA Technical Reports Server (NTRS)

    Esser, Ruth

    1998-01-01

    The ion compositions measured in situ in the solar wind are important since the ion fractions carry information on the plasma conditions in the inner corona. The conditions in the inner corona define the properties of the solar wind plasma flow. Thus, if the ion fraction measurements can be used to unravel some of the plasma parameters in the inner corona, they will provide a valuable contribution to solving the heating and acceleration problem of the solar wind. The ion charge states in the solar wind carry information on electron temperature, electron density and ion flow speed. They are also sensitive to the shape of the electron distribution function. Through carefully modeling the solar wind and calculating the ion fractions predicted for different solar wind conditions, constraints on the electron temperature and ion flow speeds can be placed if the electron density is measured using polarization brightness measurements.

  14. Radial evolution of the energy density of solar wind fluctuations

    NASA Technical Reports Server (NTRS)

    Zank, G. P.; Matthaeus, W. H.; Smith, C. W.

    1995-01-01

    On the basis of transport theories appropriate to a radially expanding solar wind, we describe new results for the radial evolution of the energy density in solar wind fluctuations at MHD scales. These models include the effects of 'mixing' and driving as well as the possibility of non-isotropic MHD turbulence. Implications of these results for solar wind heating, cosmic ray diffusion and interstellar pick-up ions will also be addressed.

  15. Far-ultraviolet studies. VII - The spectrum and latitude dependence of the local interstellar radiation field

    NASA Technical Reports Server (NTRS)

    Henry, R. C.; Anderson, R. C.; Fastie, W. G.

    1980-01-01

    A direct measurement has been made of the spectrum (1180-1680 A) and Gould-latitude dependence of the local interstellar radiation field, over about one-third of the sky. The result is corrected to give expected values for the entire sky. The average local 1180-1680 A energy density is 5.8 x 10 to the -17th ergs/cu cm A. The surface brightness falls off toward high latitudes much more steeply than published models predict.

  16. Climatology and latitudinal gradients of quiet time thermospheric neutral winds over Millstone Hill from Fabry-Perot interferometer measurements

    NASA Astrophysics Data System (ADS)

    Emmert, J. T.; Fejer, B. G.; Sipler, D. P.

    2003-05-01

    Midlatitude nighttime thermospheric neutral winds are strongly dependent on season, solar activity, and latitude. We use an extensive database of wind measurements made during 1989-2001 by the Millstone Hill Fabry-Perot interferometer to study the detailed climatology of quiet time neutral winds near an altitude of 250 km. To facilitate the analysis of these data, we develop a local time, day-of-year, solar flux, and latitude-dependent empirical model, with the latitude dependence obtained by considering north looking and south looking observations separately. Our results show that the zonal winds are predominantly eastward after dusk and westward before dawn, with the strongest eastward winds occurring in the winter and with an east-to-west transition that occurs earliest in the summer. The zonal winds exhibit weak-to-moderate latitudinal gradients, with more westward values to the north. The zonal wind magnitudes decrease with increasing solar flux; the strongest trends occur during winter. The meridional winds are predominantly equatorward in all cases and exhibit strong latitudinal gradients, with larger values to the north. The maximum nighttime equatorward winds decrease with increasing solar flux, except during summer, when there is no significant solar activity variation. They are largest during the summer, except at solar minimum when a semiannual variation is observed and the peak winds occur during the equinoxes. Earlier studies of midlatitude wind measurements are generally consistent with our data, with our results providing a considerably more detailed description of the nighttime wind climatology at midlatitudes.

  17. Time Variable Solar Wind Interaction of Mercury

    NASA Astrophysics Data System (ADS)

    Ip, W.-H.; Kopp, A.

    A three-dimensional MHD code was used to simulate the solr wind interaction of Mercury's magnetosphere with interplanetary magnetic field (IMF) of different orien- tations. It can be shown that for northward pointing IMF, the Hermean magnetosphere is nearly closed with the polar cap shrinking to a small area. On the other hand, the boundary of the polar cap expands to mid-latitude region (about 30 degrees latitude) for south-pointing IMF. Such large changes in the size and morphology of the polar cap in response to directional variations of the IMF could be related to the observed temporal variabilities of the atomic sodium emission on Mercury's disk. That is, the production rate of the sodium atoms could be significantly modulated i.e., weak for northward IMF and large for southward IMF) if solar wind sputtering of the surface material is an important source mechanism of the sodium atoms.

  18. Solar wind turbulence: anisotropy, anisotropy, anisotropy!

    NASA Astrophysics Data System (ADS)

    Wicks, R.; Forman, M. A.; Summerlin, E. J.; Roberts, D. A.; Salem, C. S.

    2014-12-01

    Turbulence heats the solar wind as it expands away from the Sun, but where and how does heating of ions and electrons occur? In order to understand this we must first look at the fluctuations making up the cascade, the properties and anisotropies of which will determine whether ions or electrons are heated and whether field-parallel or -perpendicular heating will occur, all of which amounts to a lot of different anisotropies! With this in mind, we present a review of recent advances in the observation of plasma turbulence in the solar wind and comparison with simulations; which features of solar wind turbulence are well reproduced and which need to be captured better? The first anisotropy is that of the fluctuations making up the turbulent cascade itself, fluctuations are known to be highly transverse, meaning that the perpendicular magnetic field components are dominant over the field-parallel component. The second anisotropy is that of the scaling of amplitude towards smaller scales with steeper spectra parallel to the local magnetic field direction. Observations of the anisotropy of the full power spectral tensor will be discussed, in particular with reference to Alfvenic and pseudo-Alfvenic fluctuations (effectively two different polarizations of Alfven waves), the next step beyond the traditional "slab + 2D" approach to incompressible MHD turbulence. The third anisotropy is that of the ion and electron distributions. Both sets of charged particles frequently show non-Maxwellian distributions with higher temperatures found either perpendicular to or parallel to the magnetic field direction. Proton distributions often show beams and the heavier alpha particles are often hotter than the protons. Localized structures such as current sheets and magnetic discontinuities are shown to be sites of intense and anisotropic heating. Small scale fluctuations filling the space between such discontinuities may also dissipate energy into ions and electrons, either through electric fields intrinsic to the modes generated by the turbulence or through resonant or stochastic processes. Observations show that kinetic Alfven waves are the dominant mode.

  19. Genesis Solar Wind Samples: Update of Availability

    NASA Technical Reports Server (NTRS)

    Gonzalez, C. P.; Allums, K. K.; Allton, J. H.

    2015-01-01

    The Genesis mission collected solar wind atoms for 28 months with a variety of collectors. The array wafer collector availability is displayed in the online catalog. The purpose of this report is to update the community on availability of array wafer samples and to preview other collectors which are in the process of being added to the online catalog. A total of fifteen pure materials were selected based on engineering and science requirements. Most of the materials were semiconductor wafers which were mounted on the arrays.

  20. Spectroscopic measurements of solar wind generation

    NASA Technical Reports Server (NTRS)

    Kohl, J. L.; Withbroe, G. L.; Zapata, C. A.; Noci, G.

    1983-01-01

    Spectroscopically observable quantities are described which are sensitive to the primary plasma parameters of the solar wind's source region. The method is discussed in which those observable quantities are used as constraints in the construction of empirical models of various coronal structures. Simulated observations are used to examine the fractional contributions to observed spectral intensities from coronal structures of interest which co-exist with other coronal structures along simulated lines-of-sight. The sensitivity of spectroscopic observables to the physical parameters within each of those structures is discussed.

  1. ELECTRON TRANSPORT IN THE FAST SOLAR WIND

    SciTech Connect

    Smith, H. M.; Marsch, E.; Helander, P.

    2012-07-01

    The electron velocity distribution function is studied in the extended solar corona above coronal holes (i.e., the inner part of the fast solar wind) from the highly collisional corona close to the Sun to the weakly collisional regions farther out. The electron kinetic equation is solved with a finite-element method in velocity space using a linearized Fokker-Planck collision operator. The ion density and temperature profiles are assumed to be known and the electric field and electron temperature are determined self-consistently. The results show quantitatively how much lower the electron heat flux and the thermal force are than predicted by high-collisionality theory. The sensitivity of the particle and heat fluxes to the assumed ion temperature profile and the applied boundary condition at the boundary far from the Sun is also studied.

  2. ON THE ORIGIN OF MID-LATITUDE FAST WIND: CHALLENGING THE TWO-STATE SOLAR WIND PARADIGM

    E-print Network

    Stakhiv, Mark

    The bimodal paradigm of solar wind describes a slow solar wind situated near the heliospheric current sheet while a fast wind overexpands from the poles to fill in the remainder of the heliosphere. In this paper, we challenge ...

  3. Latitudinal Dependence of Coronal Hole-Associated Fast Solar Wind

    NASA Astrophysics Data System (ADS)

    Zhao, L.; Landi, E.

    2014-05-01

    The fast solar wind can have at least two different coronal sources: high-latitude, polar coronal holes (PCH) and low-latitude, equatorial coronal holes (ECH). The in-situ differences in the PCH and ECH winds have not been well studied, nor have the differences in their evolution over the solar cycles. Ulysses' 19 years of observations from 1990 to 2009, combined with ACE observations from 1998 to the present, provide us with measurements of solar wind properties that span two entire solar cycles, which allow us to study the in-situ properties and evolution of the coronal hole-associated solar wind at different latitudes. In this work, we focus on the PCH and ECH solar winds during the minima between solar cycles 22-23 and 23-24. We use data from SWICS, SWOOPS, and VHM/FGM on board Ulysses, and SWICS, SWEPAM, and MAG on board ACE to analyze the proton dynamics, heavy ion composition, elemental abundance, and magnetic field properties of the PCH wind and ECH wind, with a special focus on their differences during the recent two solar minima. We also include the slow and hot, streamer-associated (ST) wind as a reference in the comparison. The comparison of PCH and ECH wind shows that: 1) the in-situ properties of ECH and PCH winds are significantly different during the two solar minima, and 2) the two types of coronal hole-associated solar wind respond differently to changes in solar activity strength from cycle 23 to cycle 24.

  4. Anisotropy in solar wind plasma turbulence.

    PubMed

    Oughton, S; Matthaeus, W H; Wan, M; Osman, K T

    2015-05-13

    A review of spectral anisotropy and variance anisotropy for solar wind fluctuations is given, with the discussion covering inertial range and dissipation range scales. For the inertial range, theory, simulations and observations are more or less in accord, in that fluctuation energy is found to be primarily in modes with quasi-perpendicular wavevectors (relative to a suitably defined mean magnetic field), and also that most of the fluctuation energy is in the vector components transverse to the mean field. Energy transfer in the parallel direction and the energy levels in the parallel components are both relatively weak. In the dissipation range, observations indicate that variance anisotropy tends to decrease towards isotropic levels as the electron gyroradius is approached; spectral anisotropy results are mixed. Evidence for and against wave interpretations and turbulence interpretations of these features will be discussed. We also present new simulation results concerning evolution of variance anisotropy for different classes of initial conditions, each with typical background solar wind parameters. PMID:25848082

  5. Electric conductivity of plasma in solar wind

    NASA Technical Reports Server (NTRS)

    Chertkov, A. D.

    1995-01-01

    One of the most important parameters in MHD description of the solar wind is the electric conductivity of plasma. There exist now two quite different approaches to the evaluation of this parameter. In the first one a value of conductivity taken from the most elaborated current theory of plasma should be used in calculations. The second one deals with the empirical, phenomenological value of conductivity. E.g.: configuration of interplanetary magnetic field, stretched by the expanding corona, depends on the magnitude of electrical conductivity of plasma in the solar wind. Knowing the main empirical features of the field configuration, one may estimate the apparent phenomenological value of resistance. The estimations show that the electrical conductivity should be approximately 10(exp 13) times smaller than that calculated by Spitzer. It must be noted that the empirical value should be treated with caution. Due to the method of its obtaining it may be used only for 'large-scale' description of slow processes like coronal expansion. It cannot be valid for 'quick' processes, changing the state of plasma, like collisions with obstacles, e.g., planets and vehicles. The second approach is well known in large-scale planetary hydrodynamics, stemming from the ideas of phenomenological thermodynamics. It could formulate real problems which should be solved by modern plasma physics, oriented to be adequate for complicated processes in space.

  6. The floor in the solar wind: status report

    NASA Astrophysics Data System (ADS)

    Cliver, E. W.

    2012-07-01

    Cliver & Ling (2010) recently suggested that the solar wind had a floor or ground-state magnetic field strength at Earth of ~2.8 nT and that the source of the field was the slow solar wind. This picture has recently been given impetus by the evidence presented by Schrijver et al. (2011) that the Sun has a minimal magnetic state that was approached globally in 2009, a year in which Earth was imbedded in slow solar wind ~70% of the time. A precursor relation between the solar dipole field strength at solar minimum and the peak sunspot number (SSN MAX ) of the subsequent 11-yr cycle suggests that during Maunder-type minima (when SSN MAX was ~0), the solar polar field strength approaches zero - indicating weak or absent polar coronal holes and an increase to nearly ~100% in the time that Earth spends in slow solar wind.

  7. Ulysses Composition, Plasma and Magnetic Field Observations of High Speed Solar wind Streams

    NASA Technical Reports Server (NTRS)

    Smith, E. J.

    1997-01-01

    During 1992-3 as the Ulysses spacecraft passed in and out of the southern high speed solar wind stream, the Solar Wind Ion Spectrometer, SWICS made continuous composition and temperature measurements of all major solar wind ions.

  8. 77 FR 72439 - Residential, Business, and Wind and Solar Resource Leases on Indian Land

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-05

    ...leasing procedures for a wind or solar energy project. Other tribes stated that...unique issues raised by wind and solar energy projects; therefore, this subpart...tribe is considering a wind or solar energy project that covers both...

  9. Solar wind driving of magnetospheric ULF waves: Field line resonances driven by dynamic pressure fluctuations

    E-print Network

    Lotko, William

    Solar wind driving of magnetospheric ULF waves: Field line resonances driven by dynamic pressure observational studies suggest that solar wind dynamic pressure fluctuations can drive magnetosphericFedderMobarry (LFM) global, threedimensional magnetohydrodynamic (MHD) simulations of the solar wind

  10. The solar wind in the third dimension

    SciTech Connect

    Neugebauer, M.

    1996-07-20

    For many years, solar-wind physicists have been using plasma and field data acquired near the ecliptic plane together with data on the scintillation of radio sources and remote sensing of structures in the solar corona to estimate the properties of the high-latitude solar wind. Because of the highly successful Ulysses mission, the moment of truth is now here. This paper summarizes the principal agreements and differences between the Ulysses observations and expectations. The speed of the high-latitude solar wind was even greater than anticipated. The strength of the radial component of the interplanetary magnetic field was found to be independent of latitude. The tilt of the heliospheric current sheet caused reverse corotating shocks to be observed to higher latitudes than forward corotating shocks. The energetic particles accelerated in these shocks were detected well poleward of the latitudes at which Ulysses observed the interaction regions themselves. As anticipated, there was a strong flux of outward propagating Alfven waves throughout the polar flow. Those waves were probably largely responsible for the smaller-than-anticipated increase of galactic cosmic rays with increasing latitude. As expected, the charge state or ionization temperature of heavy ions was lower in the polar flow than in low-latitude interstream flows. What was not anticipated was the correlation of elemental abundances with ionization temperatures; the Ulysses data revealed a connection between the first ionization time in the upper chromosphere and the final ionization state in the corona. As expected, transient events were detected to {approx}60 deg. latitude, but the properties of those high latitude transient flows held some surprises. At high latitudes, the speeds of the transient interplanetary plasma clouds were approximately the same as the speed of the ambient plasma and the expansion of the clouds drove forward and reverse shock pairs that had never been seen at low latitudes. At high latitudes, the plasma in interplanetary clouds differed from low-latitude events in that it was not enriched in helium and did not have high ionization temperatures.

  11. Turbulence in the solar wind: Kinetic effects

    NASA Technical Reports Server (NTRS)

    Goldstein, M. L.

    1995-01-01

    Although a casual look at the fluctuating magnetic and velocity fields in the solar wind may be reminiscent of a chaotic and disordered flow, there is, nonetheless. considerable organization and structure in the temporal and spatial evolution of those fluctuations. Much of that evolution is controlled by processes operating on rather large scales for example, in the inner heliosphere, the fluctuations in magnetic and velocity are highly correlated in the sense of outward propagating Alfven waves. This correlation can be destroyed both in time and distance by the velocity gradients present between fast and slow streams and by other nonlinear processes which stir the medium, producing a turbulent cascade of energy from large to small scales. Many aspects of this turbulent evolution can be described using fluid models; however, at some scale the fluid approximation breaks down and a more detailed paradigm is necessary. The breakdown is evident in the power spectrum of magnetic fluctuations at scales approaching the wavelength of ion cyclotron waves. At those scales, as evident in Mariner 10 and other magnetometer data, the spectrum bends over and the fluctuations damp, possibly heating the ambient plasma. Some evidence for heating of the solar wind is present in the Voyager data. Fluid models can be modified to some extent to incorporate aspects of a kinetic treatment. This is done by modifying the dissipation terms in the fluid equations and by including extra terms, such as the Hall term. As the scale lengths of phenomena shrink further and approach the spatial and temporal scales characteristic of electron phenomena, the fluid description must be abandoned altogether and a fully kinetic treatment is required. One example is the generation of Langmuir solitons produced by the electron beams that generate type 3 solar radio bursts.

  12. Venus Ionosphere and Solar Wind Interaction

    NASA Astrophysics Data System (ADS)

    Russell, C. T.; Luhmann, Janet G.; Ma, Yingjuan; Zhang, Tielong; Villarreal, M.

    Venus Express, which was inserted into orbit in mid-2006, has added significantly to the knowledge gained from Pioneer Venus from 1978 to 1992. This observational database interpreted in terms of modern multi-fluid codes and hybrid simulations has deepened our understanding of Earth’s very different twin sister planet. Furthermore, the very different orbits of VEX and PVO has allowed the more complete mapping of the volume of space around the planet. Now the bow shock has been probed over its full surface, the ionosphere mapped everywhere, and the tail studied from the ionosphere to 12 Venus radii. Some unexpected discoveries have been made. The exospheric hydrogen at Venus, unlike that at Mars, does not produce ion-cyclotron waves, perhaps because the stronger gravity of Venus produces a smaller geocorona. The solar wind interaction drapes the magnetic field around the planet, and a strong layer of magnetic field builds up at low altitudes. While the layer does not appear to penetrate into the dayside atmosphere (perhaps diffusing only slowly through the low atmosphere), it does appear to dip into the atmosphere at night. Surprisingly, over the poles, this layer is most strongly seen when the IMF BY component has a positive Y-component in Venus-Solar-Orbital coordinates. Multi-fluid simulations show that this result is consistent with the pressure of significant ion densities of ions with quite different mass which causes magnetic polarity control of the ion flow over the terminators. Reconnection is found in the tail close to the planet, and the structure of the outer tail found by PVO is confirmed to exist in the inner tail by VEX. When combined, the VEX and PVO Data provide a very comprehensive picture of the physics of the solar wind interaction with the ionosphere of Venus.

  13. Western Wind and Solar Integration Study Phase 3: Technical Overview

    SciTech Connect

    2015-11-01

    Technical fact sheet outlining the key findings of Phase 3 of the Western Wind and Solar Integration Study (WWSIS-3). NREL and GE find that with good system planning, sound engineering practices, and commercially available technologies, the Western grid can maintain reliability and stability during the crucial first minute after grid disturbances with high penetrations of wind and solar power.

  14. Correlations between solar wind parameters and auroral kilometric radiation intensity

    NASA Technical Reports Server (NTRS)

    Gallagher, D. L.; Dangelo, N.

    1981-01-01

    The relationship between solar wind properties and the influx of energy into the nightside auroral region as indicated by the intensity of auroral kilometric radiation is investigated. Smoothed Hawkeye satellite observations of auroral radiation at 178, 100 and 56.2 kHz for days 160 through 365 of 1974 are compared with solar wind data from the composite Solar Wind Plasma Data Set, most of which was supplied by the IMP-8 spacecraft. Correlations are made between smoothed daily averages of solar wind ion density, bulk flow speed, total IMF strength, electric field, solar wind speed in the southward direction, solar wind speed multiplied by total IMF strength, the substorm parameter epsilon and the Kp index. The greatest correlation is found between solar wind bulk flow speed and auroral radiation intensity, with a linear correlation coefficient of 0.78 for the 203 daily averages examined. A possible mechanism for the relationship may be related to the propagation into the nightside magnetosphere of low-frequency long-wavelength electrostatic waves produced in the magnetosheath by the solar wind.

  15. Comparative Study of MHD Modeling of the Background Solar Wind

    NASA Astrophysics Data System (ADS)

    Gressl, C.; Veronig, A. M.; Temmer, M.; Odstr?il, D.; Linker, J. A.; Miki?, Z.; Riley, P.

    2014-05-01

    Knowledge about the background solar wind plays a crucial role in the framework of space-weather forecasting. In-situ measurements of the background solar wind are only available for a few points in the heliosphere where spacecraft are located, therefore we have to rely on heliospheric models to derive the distribution of solar-wind parameters in interplanetary space. We test the performance of different solar-wind models, namely Magnetohydrodynamic Algorithm outside a Sphere/ENLIL (MAS/ENLIL), Wang-Sheeley-Arge/ENLIL (WSA/ENLIL), and MAS/MAS, by comparing model results with in-situ measurements from spacecraft located at 1 AU distance to the Sun (ACE, Wind). To exclude the influence of interplanetary coronal mass ejections (ICMEs), we chose the year 2007 as a time period with low solar activity for our comparison. We found that the general structure of the background solar wind is well reproduced by all models. The best model results were obtained for the parameter solar-wind speed. However, the predicted arrival times of high-speed solar-wind streams have typical uncertainties of the order of about one day. Comparison of model runs with synoptic magnetic maps from different observatories revealed that the choice of the synoptic map significantly affects the model performance.

  16. Solar and Wind Technologies for Hydrogen Production Report to Congress

    SciTech Connect

    None, None

    2005-12-01

    DOE's Solar and Wind Technologies for Hydrogen Production Report to Congress summarizes the technology roadmaps for solar- and wind-based hydrogen production. Published in December 2005, it fulfills the requirement under section 812 of the Energy Policy Act of 2005.

  17. Three-fluid solar wind model with Alfven waves

    NASA Technical Reports Server (NTRS)

    Esser, Ruth; Habbal, Shadia R.; Hu, You Q.

    1995-01-01

    We present a study of a three-fluid solar wind model. with continuity, momentum and separate energy equations for protons. alpha particles and electrons. Allowing separate coronal heat sources for all three species, we study the flow properties of the solar wind as a function of heat input, Alfven wave energy input, and alpha particle abundance.

  18. Lunar precursor effects in the solar wind and terrestrial magnetosphere

    E-print Network

    Bonnell, John W.

    ] The interaction of solar wind and magnetospheric plasma with the Moon and its exosphere, surface, and crustalLunar precursor effects in the solar wind and terrestrial magnetosphere J. S. Halekas,1,2 A. R activity upstream from the Moon, when magnetically connected to the dayside lunar surface. The most common

  19. Plasma Properties of Pseudostreamers and Associated Solar Wind Streams

    NASA Astrophysics Data System (ADS)

    Miralles, M. P.; Cranmer, S. R.; Stenborg, G.

    2014-12-01

    We study pseudostreamers (i.e., open-field extensions of plasma from unipolar footpoints in the corona; distinct from classical helmet streamers that have opposite-polarity footpoints) that are believed to be sources of slow to intermediate speed wind streams. We make use of multi-spacecraft and ground-based observations that extend from the solar corona to the solar wind at 1 AU. We compare the physical properties of selected pseudostreamers and helmet streamers to characterize how the differences in magnetic topology affect the plasma properties of the coronal structures and their wind. Due to the large number of pseudostreamers and their long persistence over multiple solar rotations, their contribution to the solar wind is likely to be substantial. In order to investigate solar wind heating and acceleration, we also compare our measurements with predictions from pseudostreamer and streamer theoretical models. This work is supported by NASA grant NNX10AQ58G to the Smithsonian Astrophysical Observatory.

  20. OBSERVATION OF FLUX-TUBE CROSSINGS IN THE SOLAR WIND

    SciTech Connect

    Arnold, L.; Li, G.; Li, X.; Yan, Y.

    2013-03-20

    Current sheets are ubiquitous in the solar wind. They are a major source of the solar wind MHD turbulence intermittency. They may result from nonlinear interactions of the solar wind MHD turbulence or are the boundaries of flux tubes that originate from the solar surface. Some current sheets appear in pairs and are the boundaries of transient structures such as magnetic holes and reconnection exhausts or the edges of pulsed Alfven waves. For an individual current sheet, discerning whether it is a flux-tube boundary or due to nonlinear interactions or the boundary of a transient structure is difficult. In this work, using data from the Wind spacecraft, we identify two three-current-sheet events. Detailed examination of these two events suggests that they are best explained by the flux-tube-crossing scenario. Our study provides convincing evidence supporting the scenario that the solar wind consists of flux tubes where distinct plasmas reside.

  1. Solar wind control of auroral zone geomagnetic activity

    NASA Technical Reports Server (NTRS)

    Clauer, C. R.; Mcpherron, R. L.; Searls, C.; Kivelson, M. G.

    1981-01-01

    Solar wind magnetosphere energy coupling functions are analyzed using linear prediction filtering with 2.5 minute data. The relationship of auroral zone geomagnetic activity to solar wind power input functions are examined, and a least squares prediction filter, or impulse response function is designed from the data. Computed impulse response functions are observed to have characteristics of a low pass filter with time delay. The AL index is found well related to solar wind energy functions, although the AU index shows a poor relationship. High frequency variations of auroral indices and substorm expansions are not predictable with solar wind information alone, suggesting influence by internal magnetospheric processes. Finally, the epsilon parameter shows a poorer relationship with auroral geomagnetic activity than a power parameter, having a VBs solar wind dependency.

  2. The Western Wind and Solar Integration Study Phase 2

    SciTech Connect

    Lew, D.; Brinkman, G.; Ibanez, E.; Hodge, B. M.; Hummon, M.; Florita, A.; Heaney, M.

    2013-09-01

    The electric grid is a highly complex, interconnected machine, and changing one part of the grid can have consequences elsewhere. Adding wind and solar affects the operation of the other power plants and adding high penetrations can induce cycling of fossil-fueled generators. Cycling leads to wear-and-tear costs and changes in emissions. Phase 2 of the Western Wind and Solar Integration Study (WWSIS-2) evaluated these costs and emissions and simulated grid operations for a year to investigate the detailed impact of wind and solar on the fossil-fueled fleet. This built on Phase 1, one of the largest wind and solar integration studies ever conducted, which examined operational impacts of high wind and solar penetrations in the West.

  3. The Western Wind and Solar Integration Study Phase 2

    SciTech Connect

    Lew, Debra; Brinkman, Greg; Ibanez, E.; Florita, A.; Heaney, M.; Hodge, B. -M.; Hummon, M.; Stark, G.; King, J.; Lefton, S. A.; Kumar, N.; Agan, D.; Jordan, G.; Venkataraman, S.

    2013-09-01

    The electric grid is a highly complex, interconnected machine, and changing one part of the grid can have consequences elsewhere. Adding wind and solar affects the operation of the other power plants and adding high penetrations can induce cycling of fossil-fueled generators. Cycling leads to wear-and-tear costs and changes in emissions. Phase 2 of the Western Wind and Solar Integration Study (WWSIS-2) evaluated these costs and emissions and simulated grid operations for a year to investigate the detailed impact of wind and solar on the fossil-fueled fleet. This built on Phase 1, one of the largest wind and solar integration studies ever conducted, which examined operational impacts of high wind and solar penetrations in the West(GE Energy 2010).

  4. Solar wind iron charge states preceding a driver plasma

    NASA Technical Reports Server (NTRS)

    Galvin, A. B.; Ipavich, F. M.; Gloeckler, G.; Hovestadt, D.; Tsurutani, B. T.

    1987-01-01

    Iron and silicon/sulfur charge state and velocity measurements and iron density measurements in the shocked solar wind which preceded the flare-related driver plasma observed on September 29, 1978 by ISEE 3 are reported. Given the assumption that the driver plasma is magnetically isolated from the ambient solar wind, the contact surface separating these two plasma regimes is expected to form an distinct boundary in the charge state composition. Instead, an apparent transition in the ionization state of the shocked solar wind from ambient solar wind values to those typical of the driver plasma is observed. This result may reflect X-ray ionization of the solar wind plasma near the flare site.

  5. Short-scale variations of the solar wind helium abundance

    SciTech Connect

    Šafránková, J.; N?me?ek, Z.; Cagaš, P.; P?ech, L.; Pavl?, J.; Zastenker, G. N.; Riazantseva, M. O.; Koloskova, I. V.

    2013-11-20

    Abrupt changes of the relative He abundance in the solar wind are usually attributed to encounters with boundaries dividing solar wind streams from different sources in the solar corona. This paper presents a systematic study of fast variations of the He abundance that supports the idea that a majority of these variations on short timescales (3-30 s) are generated by in-transit turbulence that is probably driven by the speed difference between the ion species. This turbulence contributes to the solar wind heating and leads to a correlation of the temperature with He abundance.

  6. Solar-wind tritium limit and nuclear processes in the solar atmosphere

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.; Damico, J.; Defelice, J.

    1975-01-01

    Tritium in Surveyor 3 material is measured, and the resulting H-3/H-1 ratio for the solar wind is applied in a solar flare-solar wind relation to investigate the mixing requirements for the solar atmosphere. The flare-wind relation is derived. None of the tritium can be attributed to solar-wind implantation. The upper limit for the H-3/He ratio in the solar wind is 4 times 10 to the minus tenth power and corresponds to a H-3/H-1 limit of 2 times 10 to the minus eleventh power. This limit imposes a requirement on the mixing rate in the solar atmosphere if the H-3 production rate in solar-surface nuclear reactions is greater than 160/sq cm per sec.

  7. Forms of Eulerian correlation functions in the solar wind

    E-print Network

    A. Shalchi

    2008-09-07

    Current spacecraft missions such as Wind and ACE can be used to determine magnetic correlation functions in the solar wind. Data sets from these missions can, in principle, also be used to compute so-called Eulerian correlation functions. These temporal correlations are essential for understanding the dynamics of solar wind turbulence. In the current article we calculate these dynamical correlations by using well-established methods. These results are very useful for a comparison with Eulerian correlations obtained from space craft missions.

  8. A tilted-dipole MHD model of the solar corona and solar wind A. V. Usmanov1

    E-print Network

    Usmanov, Arcadi V.

    a bimodal solar wind with a sharp transition from a relatively uniform fast and tenuous wind at high latitudes to a slower and denser wind near the solar equator [Phillips et al., 1995]. The magnetic field

  9. Comparing Solar Wind Prediction Models at 5.2 AU

    NASA Astrophysics Data System (ADS)

    Freed, A. J.; Russell, C. T.

    2012-12-01

    The solar wind is the main driver of Earth's magnetosphere, but at the gas giant Jupiter, where the rotation period is only ~10 hours and the solar wind is much less dense, its role is unclear. Previous studies investigating the role of the solar wind on Jupiter have been limited to the time and place spacecraft were able to take measurements. This study, in contrast, has created a continuous database of solar wind conditions near Jupiter. Such a database was constructed from the solar wind propagation model ENLIL and the Wang-Sheeley-Arge (WSA) solar corona model by averaging the model output into 10-minute bins to match the Galileo database. These predictions will be useful for jovian missions probing the magnetosphere without an accompanying solar wind monitor. Before they are used, however, their accuracy needs to be determined. This will be done by comparing the WSA-ENLIL results to spacecraft solar wind observations near Jupiter, as well as at other points along the alignment of the Sun and Jupiter.

  10. First Results from the Genesis Autonomous Solar Wind Regime Algorithm

    NASA Astrophysics Data System (ADS)

    Steinberg, J. T.; Barraclough, B.; Bremmer, R. R.; Dors, E. E.; Gosling, J. T.; Neugebauer, M.; Skoug, R. M.; Tokar, R. L.; Wiens, R. C.

    2001-12-01

    Launched on August 8, 2001, the NASA Genesis mission will collect samples of the solar wind in various materials for approximately two years, and return those samples to Earth for analysis. A primary science goal of Genesis is the determination of the elemental and isotopic composition of the solar atmosphere from the solar wind material returned. Because the solar wind itself is known to exhibit compositional variations across different types of solar wind flows, Genesis will expose different collectors to solar wind originating from three flow types: coronal hole (CH), coronal mass ejection (CME) and interstream (IS) flows. Flow types are identified using in situ measurements of solar wind ions and electrons from electrostatic analyzers carried by Genesis. The flow regime selection algorithm and subsequent array deployment on Genesis act autonomously, taking into account the proton speed, proton temperature, alpha particle abundance, and the presence of counter-streaming suprathermal electrons as determined onboard. Autonomous determination of counter-streaming electrons is novel, as is the simultaneous utilization of electron information and ion moments in logic that autonomously controls the science payload. We will report on the first four months of algorithm performance, comparing the onboard results to an assessment of regime based on post analysis of the in situ solar wind measurements. At the time of this writing, the regime algorithm has been active for eleven days, choosing regime IS for the first ten days, then transitioning to CH. In addition two interplanetary shocks have been correctly identified.

  11. Solar Energetic Particle Events in Different Types of Solar Wind

    NASA Astrophysics Data System (ADS)

    Kahler, Stephen W.; Vourlidas, Angelos

    2014-06-01

    We examine statistically some properties of 96 20 MeV gradual solar energetic proton (SEP) events as a function of three different types of solar winds (SWs) as classified by Richardson and Cane (2012). Gradual SEP (E > 10 MeV) events are produced in shocks driven by fast (V > 900 km/s) and wide (W > 60 deg) coronal mass ejections (CMEs). We find no differences between transient and fast or slow SW streams for SEP 20-MeV event timescales. It has recently been found that the peak intensities Ip of these SEP events scale with the ~ 2 MeV proton background intensities, which may be a proxy for the near-Sun shock seed particles. Both the intensities Ip and their 2 MeV backgrounds are significantly enhanced in transient SW compared to those of fast and slow SW streams, and the values of Ip normalized to the 2 MeV backgrounds only weakly correlate with CME V for all SW types. This result implies that forecasts of SEP events could be improved by monitoring both the Sun and the local SW stream properties and that the well known power-law size distributions of Ip may differ between transient and long-lived SW streams. We interpret an observed correlation between CME V and the 2 MeV background for SEP events in transient SW as a manifestation of enhanced solar activity.

  12. Solar energetic particle events in different types of solar wind

    SciTech Connect

    Kahler, S. W.; Vourlidas, A.

    2014-08-10

    We examine statistically some properties of 96 20 MeV gradual solar energetic proton (SEP) events as a function of three different types of solar wind (SW) as classified by Richardson and Cane. Gradual SEP (E > 10 MeV) events are produced in shocks driven by fast (V ? 900 km s{sup –1}) and wide (W > 60°) coronal mass ejections (CMEs). We find no differences among the transient, fast, and slow SW streams for SEP 20 MeV proton event timescales. It has recently been found that the peak intensities Ip of these SEP events scale with the ?2 MeV proton background intensities, which may be a proxy for the near-Sun shock seed particles. Both the intensities Ip and their 2 MeV backgrounds are significantly enhanced in transient SW compared to those of fast and slow SW streams, and the values of Ip normalized to the 2 MeV backgrounds only weakly correlate with CME V for all SW types. This result implies that forecasts of SEP events could be improved by monitoring both the Sun and the local SW stream properties and that the well known power-law size distributions of Ip may differ between transient and long-lived SW streams. We interpret an observed correlation between CME V and the 2 MeV background for SEP events in transient SW as a manifestation of enhanced solar activity.

  13. Solar Energetic Particle Events in Different Types of Solar Wind

    NASA Astrophysics Data System (ADS)

    Kahler, S. W.; Vourlidas, A.

    2014-08-01

    We examine statistically some properties of 96 20 MeV gradual solar energetic proton (SEP) events as a function of three different types of solar wind (SW) as classified by Richardson and Cane. Gradual SEP (E > 10 MeV) events are produced in shocks driven by fast (V >~ 900 km s-1) and wide (W > 60°) coronal mass ejections (CMEs). We find no differences among the transient, fast, and slow SW streams for SEP 20 MeV proton event timescales. It has recently been found that the peak intensities Ip of these SEP events scale with the ~2 MeV proton background intensities, which may be a proxy for the near-Sun shock seed particles. Both the intensities Ip and their 2 MeV backgrounds are significantly enhanced in transient SW compared to those of fast and slow SW streams, and the values of Ip normalized to the 2 MeV backgrounds only weakly correlate with CME V for all SW types. This result implies that forecasts of SEP events could be improved by monitoring both the Sun and the local SW stream properties and that the well known power-law size distributions of Ip may differ between transient and long-lived SW streams. We interpret an observed correlation between CME V and the 2 MeV background for SEP events in transient SW as a manifestation of enhanced solar activity.

  14. Variation of the plasmasheet O+ and H+ density with solar activity and solar wind conditions

    NASA Astrophysics Data System (ADS)

    Maggiolo, Romain; Kistler, Lynn; Keyser Johan, De; Emmanuel, Gamby

    2014-05-01

    A modulation of the outflow rate of ionospheric ions - among which a high proportion of O+ ions - by solar EUV flux and solar wind conditions has been evidenced in several observational studies. Similarly, the amount of solar wind plasma - mostly H+ ions - penetrating into the magnetosphere also depends on solar wind conditions. We use long-term measurements from the CODIF ion detector onboard the Cluster spacecraft to quantify the resulting O+ and H+ density variations in the plasmasheet. CODIF data are mapped along magnetic field lines to assess the spatial distribution of O+ and H+ ions at the magnetospheric equatorial plane. We make a multi-correlation analysis between the O+ and H+ density and solar wind parameters to investigate their impact on the plasmasheet composition in various regions. An emphasis is placed on the effect of solar wind pressure on the plasmasheet O+ content. Solar wind pressure is expected to affect the energy and momentum input into the ionosphere, which in turn should modulate the ionospheric ion outflow rate and thus the plasmasheet O+ density. On the other hand, when the solar wind pressure increases, the magnetosphere is compressed, resulting in an increase of the O+ and H+ densities independently of the ionospheric outflow rate variation. To infer the actual influence of the solar wind pressure on the plasmasheet O+ content we compare the O+ and H+ density variations associated with solar wind pressure changes with density variations due to magnetospheric compression alone.

  15. Microstructures in the Polar Solar Wind: Ulysses

    NASA Technical Reports Server (NTRS)

    Tsuruyani, Bruce T.; Arballo, J. K.; Galvan, C.; Goldstein, B. E.; Lakhina, G. S.; Sakurai, R.; Smith, E. J.; Neugebauer, M.

    1999-01-01

    We find that small (10-200 rP) magnetic decreases comprise a dominant part of the polar solar wind microstructure at Ulysses distances (2.2 AU). These magnetic field dips are almost always bounded by tangential discontinuities, a feature which is not well understood at this time. Hundreds of these events have been examined in detail and a variety of types have been found. These will be described. It is speculated that these structures have been generated by perpendicular heating of ions closer to the Sun and have then been convected to distances of Ulysses. Such structures may be very important for the rapid cross- field diffusion of ions in the polar regions of the heliosphere.

  16. Innovations in Wind and Solar PV Financing

    SciTech Connect

    Cory, K.; Coughlin, J.; Jenkin, T.; Pater, J.; Swezey, B.

    2008-02-01

    There is growing national interest in renewable energy development based on the economic, environmental, and security benefits that these resources provide. Historically, greater development of our domestic renewable energy resources has faced a number of hurdles, primarily related to cost, regulation, and financing. With the recent sustained increase in the costs and associated volatility of fossil fuels, the economics of renewable energy technologies have become increasingly attractive to investors, both large and small. As a result, new entrants are investing in renewable energy and new business models are emerging. This study surveys some of the current issues related to wind and solar photovoltaic (PV) energy project financing in the electric power industry, and identifies both barriers to and opportunities for increased investment.

  17. RELAXATION PROCESSES IN SOLAR WIND TURBULENCE

    SciTech Connect

    Servidio, S.; Carbone, V.; Gurgiolo, C.; Goldstein, M. L.

    2014-07-10

    Based on global conservation principles, magnetohydrodynamic (MHD) relaxation theory predicts the existence of several equilibria, such as the Taylor state or global dynamic alignment. These states are generally viewed as very long-time and large-scale equilibria, which emerge only after the termination of the turbulent cascade. As suggested by hydrodynamics and by recent MHD numerical simulations, relaxation processes can occur during the turbulent cascade that will manifest themselves as local patches of equilibrium-like configurations. Using multi-spacecraft analysis techniques in conjunction with Cluster data, we compute the current density and flow vorticity and for the first time demonstrate that these localized relaxation events are observed in the solar wind. Such events have important consequences for the statistics of plasma turbulence.

  18. Nonaxisymmetric anisotropy of solar wind turbulence.

    PubMed

    Turner, A J; Gogoberidze, G; Chapman, S C; Hnat, B; Müller, W-C

    2011-08-26

    A key prediction of turbulence theories is frame-invariance, and in magnetohydrodynamic (MHD) turbulence, axisymmetry of fluctuations with respect to the background magnetic field. Paradoxically the power in fluctuations in the turbulent solar wind are observed to be ordered with respect to the bulk macroscopic flow as well as the background magnetic field. Here, nonaxisymmetry across the inertial and dissipation ranges is quantified using in situ observations from Cluster. The observed inertial range nonaxisymmetry is reproduced by a "fly through" sampling of a direct numerical simulation of MHD turbulence. Furthermore, fly through sampling of a linear superposition of transverse waves with axisymmetric fluctuations generates the trend in nonaxisymmetry with power spectral exponent. The observed nonaxisymmetric anisotropy may thus simply arise as a sampling effect related to Taylor's hypothesis and is not related to the plasma dynamics itself. PMID:21929247

  19. Synthetic four-solar-cycle solar wind at 1 AU generated from the OMNI data set

    NASA Astrophysics Data System (ADS)

    Thatcher, L. J.; Müller, H.-R.

    2013-02-01

    Abstract Numerical modeling provides key insights into the physics of the outer heliosphere. The <span class="hlt">solar</span> <span class="hlt">wind</span> data utilized by these models impact their accuracy and should be as close as possible to the actual <span class="hlt">solar</span> <span class="hlt">wind</span>. Because of the time scales involved, such a data set should also span several <span class="hlt">solar</span> cycles. Yet the bulk of <span class="hlt">solar</span> <span class="hlt">wind</span> measurements in such a time frame was obtained near Earth. A method to infer the <span class="hlt">solar</span> <span class="hlt">wind</span> at points not directly observed is developed such that a 1 AU ring in the ecliptic plane is filled with four <span class="hlt">solar</span> cycles of <span class="hlt">solar</span> <span class="hlt">wind</span> data. Hourly OMNI data are used as the seed data. The OMNI data are separated into four separate categories, and those categories are first extrapolated, generating a continuous 2-D category map of the <span class="hlt">solar</span> <span class="hlt">wind</span> for the full four <span class="hlt">solar</span> cycles covered by OMNI. The category map is used to determine <span class="hlt">solar</span> <span class="hlt">wind</span> characteristics. The <span class="hlt">solar</span> <span class="hlt">wind</span> values are determined by local running averages coupled with a random walk technique. The averages provide baseline values and the random walk adds short-duration deviations from this baseline. The statistics from the extrapolated data are compared to the statistics of the original OMNI data set. Category durations, relative coverage, variable distributions, and correlations are similar to those of the OMNI data, although with some discrepancies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5601625','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5601625"><span id="translatedtitle"><span class="hlt">Wind</span> and radiant <span class="hlt">solar</span> energy for drying fruits and vegetables</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wagner, C.J. Jr.; Coleman, R.L.; Berry, R.E.</p> <p>1981-01-01</p> <p>The combination of <span class="hlt">wind</span> with radiant <span class="hlt">solar</span> energy for drying fruits and vegetables can help promote conservation of food and nonrenewable energy resources. Low-cost, small-scale <span class="hlt">solar</span> dryers have been developed with the potential for developing larger dryers. These dryers depend on natural air convection to remove moisture. Designing the dryers to incorporate natural <span class="hlt">wind</span> currents, providing forced air circulation, could increase drying rates. Preliminary studies to provide information for such designs included: (1) comparing drying tests with and without forced air circulation, (2) monitoring <span class="hlt">wind</span> speeds on-site, and (3) testing <span class="hlt">wind</span> collecting devices. Average <span class="hlt">wind</span> speeds during <span class="hlt">solar</span> periods were higher than air velocities from unassisted air convection in these small food dryers. Drying rates were increased by 6 to 11% when the natural convection dryer was provided with a small electric fan. Either of two <span class="hlt">wind</span> collecting devices also could increase drying rates.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cses.anu.edu.au/files/pubs2000_Solar_Wind.pdf','EPRINT'); return false;" href="http://cses.anu.edu.au/files/pubs2000_Solar_Wind.pdf"><span id="translatedtitle">A.W. Blakers, '<span class="hlt">Solar</span> and <span class="hlt">Wind</span> Electricity in Australia', Australian Journal of Environmental Management, Vol 7, pp 223-236, 2000 <span class="hlt">SOLAR</span> AND <span class="hlt">WIND</span> ELECTRICITY IN AUSTRALIA</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>A.W. Blakers, '<span class="hlt">Solar</span> and <span class="hlt">Wind</span> Electricity in Australia', Australian Journal of Environmental Management, Vol 7, pp 223-236, 2000 <span class="hlt">SOLAR</span> AND <span class="hlt">WIND</span> ELECTRICITY IN AUSTRALIA Andrew Blakers Centre), <span class="hlt">solar</span> thermal electricity (STE) and <span class="hlt">wind</span>. PV, STE and <span class="hlt">wind</span> have immense resources and small</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19820012230','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820012230"><span id="translatedtitle">Evidence for <span class="hlt">solar</span> <span class="hlt">wind</span> control of Saturn radio emission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Desch, M. D.</p> <p>1982-01-01</p> <p>Using data collected by the Voyager 1 and 2 spacecraft in 1980 and 1981, strong evidence is presented for a direct correlation between variations in the <span class="hlt">solar</span> <span class="hlt">wind</span> at Saturn and the level of activity of Saturn's nonthermal radio emission. Correlation coefficients of 57 to 58% are reached at lag times of 0 to 1 days between the arrival at Saturn of high pressure <span class="hlt">solar</span> <span class="hlt">wind</span> streams and the onset of increased radio emission. The radio emission exhibits a long-term periodicity of 25 days, identical to the periodicity seen in the <span class="hlt">solar</span> <span class="hlt">wind</span> at this time and consistent with the <span class="hlt">solar</span> rotation period. The energy coupling efficiency between the <span class="hlt">solar</span> <span class="hlt">wind</span> with the Saturn radio emission is estimated and compared with that for Earth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19750055576&hterms=Burlingame&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DBurlingame','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19750055576&hterms=Burlingame&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DBurlingame"><span id="translatedtitle">Simulation of lunar carbon chemistry. I - <span class="hlt">Solar</span> <span class="hlt">wind</span> contribution</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bibring, J. P.; Chaumont, J.; Langevin, Y.; Maurette, M.; Burlingame, A. L.; Wszolek, P. C.</p> <p>1974-01-01</p> <p>Simulation experiments were conducted to identify the role of <span class="hlt">solar</span> and lunar <span class="hlt">winds</span> in the evolution of lunar carbon chemistry. Major conclusions are that (1) implantation of <span class="hlt">solar</span> <span class="hlt">wind</span> C, D, and N ions in silicates synthesizes small molecules that can be released into vacuum either by ion sputtering or by heating; (2) this synthesis is highly specific when compared to other processes accounting for the formation of molecules in the <span class="hlt">solar</span> nebula or in interstellar space; (3) the carbon injected by the <span class="hlt">solar</span> <span class="hlt">wind</span> in the crystalline component of mature soils should reach a saturation concentration of about 200 ppm; and (4) the carbon chemistry of the crystalline component of mature soils is dominated by <span class="hlt">solar</span> <span class="hlt">wind</span> implantation effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPhCS.642a2016M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPhCS.642a2016M"><span id="translatedtitle">Modeling <span class="hlt">solar</span> <span class="hlt">wind</span> with boundary conditions from interplanetary scintillations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Manoharan, P.; Kim, T.; Pogorelov, N. V.; Arge, C. N.; Manoharan, P. K.</p> <p>2015-09-01</p> <p>Interplanetary scintillations make it possible to create three-dimensional, time- dependent distributions of the <span class="hlt">solar</span> <span class="hlt">wind</span> velocity. Combined with the magnetic field observations in the <span class="hlt">solar</span> photosphere, they help perform <span class="hlt">solar</span> <span class="hlt">wind</span> simulations in a genuinely time-dependent way. Interplanetary scintillation measurements from the Ooty Radio Astronomical Observatory in India provide directions to multiple stars and may assure better resolution of transient processes in the <span class="hlt">solar</span> <span class="hlt">wind</span>. In this paper, we present velocity distributions derived from Ooty observations and compare them with those obtained with the Wang-Sheeley-Arge (WSA) model. We also present our simulations of the <span class="hlt">solar</span> <span class="hlt">wind</span> flow from 0.1 AU to 1 AU with the boundary conditions based on both Ooty and WSA data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1010.2065.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1010.2065.pdf"><span id="translatedtitle">Dynamics of <span class="hlt">solar</span> <span class="hlt">wind</span> protons reflected by the Moon</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Holmstrom, M; Barabash, S; Futaana, Y; Bhardwaj, A; 10.1029/2009JA014843</p> <p>2010-01-01</p> <p><span class="hlt">Solar</span> system bodies that lack a significant atmosphere and significant internal magnetic fields, such as the Moon and asteroids, have been considered as passive absorbers of the <span class="hlt">solar</span> <span class="hlt">wind</span>. However, ion observations near the Moon by the SELENE spacecraft show that a fraction of the impacting <span class="hlt">solar</span> <span class="hlt">wind</span> protons are reflected by the surface of the Moon. Using new observations of the velocity spectrum of these reflected protons by the SARA experiment on-board the Chandrayaan-1 spacecraft at the Moon, we show by modeling that the reflection of <span class="hlt">solar</span> <span class="hlt">wind</span> protons will affect the global plasma environment. These global perturbations of the ion fluxes and the magnetic fields will depend on microscopic properties of the object's reflecting surface. This <span class="hlt">solar</span> <span class="hlt">wind</span> reflection process could explain past ion observations at the Moon, and the process should occur universally at all atmosphereless non-magnetized objects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18046399','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18046399"><span id="translatedtitle">Little or no <span class="hlt">solar</span> <span class="hlt">wind</span> enters Venus' atmosphere at <span class="hlt">solar</span> minimum.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, T L; Delva, M; Baumjohann, W; Auster, H-U; Carr, C; Russell, C T; Barabash, S; Balikhin, M; Kudela, K; Berghofer, G; Biernat, H K; Lammer, H; Lichtenegger, H; Magnes, W; Nakamura, R; Schwingenschuh, K; Volwerk, M; Vörös, Z; Zambelli, W; Fornacon, K-H; Glassmeier, K-H; Richter, I; Balogh, A; Schwarzl, H; Pope, S A; Shi, J K; Wang, C; Motschmann, U; Lebreton, J-P</p> <p>2007-11-29</p> <p>Venus has no significant internal magnetic field, which allows the <span class="hlt">solar</span> <span class="hlt">wind</span> to interact directly with its atmosphere. A field is induced in this interaction, which partially shields the atmosphere, but we have no knowledge of how effective that shield is at <span class="hlt">solar</span> minimum. (Our current knowledge of the <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with Venus is derived from measurements at <span class="hlt">solar</span> maximum.) The bow shock is close to the planet, meaning that it is possible that some <span class="hlt">solar</span> <span class="hlt">wind</span> could be absorbed by the atmosphere and contribute to the evolution of the atmosphere. Here we report magnetic field measurements from the Venus Express spacecraft in the plasma environment surrounding Venus. The bow shock under low <span class="hlt">solar</span> activity conditions seems to be in the position that would be expected from a complete deflection by a magnetized ionosphere. Therefore little <span class="hlt">solar</span> <span class="hlt">wind</span> enters the Venus ionosphere even at <span class="hlt">solar</span> minimum. PMID:18046399</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6517833','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6517833"><span id="translatedtitle"><span class="hlt">Wind</span> loading on <span class="hlt">solar</span> concentrators: some general considerations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Roschke, E. J.</p> <p>1984-05-01</p> <p>A survey has been completed to examine the problems and complications arising from <span class="hlt">wind</span> loading on <span class="hlt">solar</span> concentrators. <span class="hlt">Wind</span> loading is site specific and has an important bearing on the design, cost, performance, operation and maintenance, safety, survival, and replacement of <span class="hlt">solar</span> collecting systems. Emphasis herein is on paraboloidal, two-axis tracking systems. Thermal receiver problems also are discussed. <span class="hlt">Wind</span> characteristics are discussed from a general point of view; current methods for determining design <span class="hlt">wind</span> speed are reviewed. Aerodynamic coefficients are defined and illustrative examples are presented. <span class="hlt">Wind</span> tunnel testing is discussed, and environmental <span class="hlt">wind</span> tunnels are reviewed; recent results on heliostat arrays are reviewed as well. Aeroelasticity in relation to structural design is discussed briefly. <span class="hlt">Wind</span> loads, i.e., forces and moments, are proportional to the square of the mean <span class="hlt">wind</span> velocity. Forces are proportional to the square of concentrator diameter, and moments are proportional to the cube of diameter. Thus, <span class="hlt">wind</span> loads have an important bearing on size selection from both cost and performance standpoints. It is concluded that sufficient information exists so that reasonably accurate predictions of <span class="hlt">wind</span> loading are possible for a given paraboloidal concentrator configuration, provided that reliable and relevant <span class="hlt">wind</span> conditions are specified. Such predictions will be useful to the design engineer and to the systems engineer as well. Information is lacking, however, on <span class="hlt">wind</span> effects in field arrays of paraboloidal concentrators. <span class="hlt">Wind</span> tunnel tests have been performed on model heliostat arrays, but there are important aerodynamic differences between heliostats and paraboloidal dishes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUSMSH43A..02R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUSMSH43A..02R"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> observations using the Mexican Array Radio Telescope (MEXART)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Romero-Hernandez, E.; Gonzalez-Esparza, A.; Villanueva, P.; Aguilar-Rodriguez, E.; Mejia-Ambriz, J. C.; Mexart</p> <p>2013-05-01</p> <p>The Mexican Array Radiotelescope (MEXART) is an instrument devoted to observations of radio sources to study large-scale structures in the <span class="hlt">solar</span> <span class="hlt">wind</span> employing the Interplanetary Scintillation (IPS) technique. We report recent IPS observations, from January to April of 2013, including an analysis of the scintillation index and the estimation of <span class="hlt">solar</span> <span class="hlt">wind</span> velocities for a set of radio sources. We track the first ICMEs registered by the MEXART. We are initiating a continuos operation for a complete monitoring of IPS radio sources that will complement <span class="hlt">solar</span> <span class="hlt">wind</span> studies based on in-situ observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19850016254&hterms=physical+activity+academic+achievement&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dphysical%2Bactivity%2Bacademic%2Bachievement','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19850016254&hterms=physical+activity+academic+achievement&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dphysical%2Bactivity%2Bacademic%2Bachievement"><span id="translatedtitle">Coupling of the <span class="hlt">solar</span> <span class="hlt">wind</span> to measures of magnetic activity</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcpherron, R. L.; Fay, R. A.; Garrity, C. R.; Bargatze, L. F.; Clauer, C. R.; Searls, C.; Baker, D. N.</p> <p>1984-01-01</p> <p>Linear prediction filtering was used to generate empirical response functions relating the <span class="hlt">solar</span> <span class="hlt">wind</span> electric field to the magnetic indices, AL, AU, Dst and ASYM. The empirical response functions were convolved with <span class="hlt">solar</span> <span class="hlt">wind</span> observations obtained during the International Magnetospheric Study to predict the indices. The predictions are compared with the observed indices during two, 3-day intervals. Differences between the observed and predicted indices are discussed in terms of the linear assumption and in terms of physical processes other than direct <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere interaction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830016174','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830016174"><span id="translatedtitle">The relationship between Saturn kilometric radiation and the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Desch, M. D.; Rucker, H. O.</p> <p>1983-01-01</p> <p>Voyager spacecraft radio, interplanetary plasma, and interplanetary magnetic field data are used to show that large amplitude fluctuations in the power generated by the Saturn kilometric radio emission are best correlated with <span class="hlt">solar</span> <span class="hlt">wind</span> ram pressure variation. In all, thirteen <span class="hlt">solar</span> <span class="hlt">wind</span> quantities previously found important in driving terrestrial magnetospheric substorms and other auroral processes were examined for evidence of correlations with the Saturn radio emission. The results are consistent with hydromagnetic wave or eddy diffusion processes driven by large scale <span class="hlt">solar</span> <span class="hlt">wind</span> pressure changes at Saturn's dayside magnetopause.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/astro-ph/0703527v1','EPRINT'); return false;" href="http://arxiv.org/pdf/astro-ph/0703527v1"><span id="translatedtitle">Quantifying shear-induced wave transformations in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Grigol Gogoberidze; Andria Rogava; Stefaan Poedts</p> <p>2007-03-20</p> <p>The possibility of velocity shear-induced linear transformations of different magnetohydrodynamic waves in the <span class="hlt">solar</span> <span class="hlt">wind</span> is studied both analytically and numerically. A quantitative analysis of the wave transformation processes for all possible plasma-$\\beta$ regimes is performed. By applying the obtained criteria for effective wave coupling to the <span class="hlt">solar</span> <span class="hlt">wind</span> parameters, we show that velocity shear-induced linear transformations of Alfv\\'en waves into magneto-acoustic waves could effectively take place for the relatively low-frequency Alfv\\'en waves in the energy containing interval. The obtained results are in a good qualitative agreement with the observed features of density perturbations in the <span class="hlt">solar</span> <span class="hlt">wind</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21394380','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21394380"><span id="translatedtitle">MEASUREMENTS OF RAPID DENSITY FLUCTUATIONS IN THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Malaspina, D. M.; Ergun, R. E.; Kellogg, P. J.; Bale, S. D.</p> <p>2010-03-01</p> <p>The power spectrum of density fluctuations in the <span class="hlt">solar</span> <span class="hlt">wind</span> is inferred by tracking small timescale changes in the electron plasma frequency during periods of strong Langmuir wave activity. STEREO electric field waveform data are used to produce time profiles of plasma density from which the density power spectrum is derived. The power spectra obtained by this method extend the observed frequency range by an order of magnitude while remaining consistent with previous results near a few Hertz. Density power spectral indices are found to be organized by the angle between the local magnetic field and the <span class="hlt">solar</span> <span class="hlt">wind</span> direction, indicating significant anisotropy in <span class="hlt">solar</span> <span class="hlt">wind</span> high-frequency density turbulence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19780062906&hterms=Burlingame&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DBurlingame','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19780062906&hterms=Burlingame&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DBurlingame"><span id="translatedtitle"><span class="hlt">Solar-wind</span> and <span class="hlt">solar</span>-flare maturation of the lunar regolith</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bibring, J. P.; Borg, J.; Vassent, B.; Burlingame, A. L.; Langevin, Y.; Maurette, M.</p> <p>1975-01-01</p> <p>Detailed predictions concerning the depth and time-dependent accumulation of <span class="hlt">solar-wind</span> effects and <span class="hlt">solar</span>-flare tracks in lunar dust grains were obtained by use of an adaptation of a Monte Carlo soil-mixing computer code described by Duraud et al. (1975). The predictions are compared to experimental measurements obtained by analyzing lunar dust grains as well as artificially irradiated minerals by a variety of techniques. A study of amorphous coatings of <span class="hlt">solar-wind</span> radiation-damaged material on certain lunar grains sets limits on the integrated residence time of these grains in the ancient <span class="hlt">solar</span> <span class="hlt">wind</span>. Other topics discussed include <span class="hlt">solar</span> <span class="hlt">wind</span> maturation, the peculiar shape of the experimental distribution of central track densities in 50-micron grains, and the interpretation of both track gradients in 50-micron feldspars and the relatively 'low' concentration of <span class="hlt">solar-wind</span> species implanted in ilmenite grains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AnGeo..33..845M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AnGeo..33..845M"><span id="translatedtitle"><span class="hlt">Solar-wind</span> control of plasma sheet dynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Myllys, M.; Kilpua, E.; Pulkkinen, T.</p> <p>2015-07-01</p> <p>The purpose of this study is to quantify how <span class="hlt">solar-wind</span> conditions affect the energy and plasma transport in the geomagnetic tail and its large-scale configuration. To identify the role of various effects, the magnetospheric data were sorted according to different <span class="hlt">solar-wind</span> plasma and interplanetary magnetic field (IMF) parameters: speed, dynamic pressure, IMF north-south component, epsilon parameter, Auroral Electrojet (AE) index and IMF ultra low-frequency (ULF) fluctuation power. We study variations in the average flow speed pattern and the occurrence rate of fast flow bursts in the magnetotail during different <span class="hlt">solar-wind</span> conditions using magnetospheric data from five Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission spacecraft and <span class="hlt">solar-wind</span> data from NASA's OMNIWeb. The time interval covers the years from 2008 to 2011 during the deep <span class="hlt">solar</span> minimum between cycles 23 and 24 and the relatively quiet rising phase of cycle 24. Hence, we investigate magnetospheric processes and <span class="hlt">solar-wind</span>-magnetospheric coupling during a relatively quiet state of the magnetosphere. We show that the occurrence rate of the fast (|Vtail| > 100 km s-1) sunward flows varies under different <span class="hlt">solar-wind</span> conditions more than the occurrence of the fast tailward flows. The occurrence frequency of the fast tailward flows does not change much with the <span class="hlt">solar-wind</span> conditions. We also note that the sign of the IMF BZ has the most visible effect on the occurrence rate and pattern of the fast sunward flows. High-speed flow bursts are more common during the slow than fast <span class="hlt">solar-wind</span> conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.physics.unh.edu/sites/physics.unh.edu/files/docs/2009_seniorthesis_Tessein.pdf','EPRINT'); return false;" href="http://www.physics.unh.edu/sites/physics.unh.edu/files/docs/2009_seniorthesis_Tessein.pdf"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> Turbulence A Study of Corotating Interaction Regions at 1 AU</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p><span class="hlt">Solar</span> <span class="hlt">Wind</span> Turbulence A Study of Corotating Interaction Regions at 1 AU Je rey A. Tessein Department of Physics University of New Hampshire Durham, NH 03824 May 15, 2009 #12;Abstract The <span class="hlt">solar</span> <span class="hlt">wind</span>'s rotation and the variability in the source of the <span class="hlt">solar</span> <span class="hlt">wind</span>, fast moving <span class="hlt">wind</span> can crash into slow <span class="hlt">wind</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2003_sw_202.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2003_sw_202.pdf"><span id="translatedtitle">Narrow coronal holes in Yohkoh soft X-ray images and the slow <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>Narrow coronal holes in Yohkoh soft X-ray images and the slow <span class="hlt">solar</span> <span class="hlt">wind</span> C.N. Arge , K.L. Harvey of this phenomenon, and have found several candidates. From observations of the associated <span class="hlt">solar</span> <span class="hlt">wind</span>, and from modeling, we find these regions to be sources of slow <span class="hlt">solar</span> <span class="hlt">wind</span>. INTRODUCTION The <span class="hlt">solar</span> <span class="hlt">wind</span> arguably</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.physics.unh.edu/sites/physics.unh.edu/files/docs/2008_seniorthesis_Sodaitis.pdf','EPRINT'); return false;" href="http://www.physics.unh.edu/sites/physics.unh.edu/files/docs/2008_seniorthesis_Sodaitis.pdf"><span id="translatedtitle">Shock Acceleration of the Energetic Particle Background in the <span class="hlt">Solar</span> <span class="hlt">Wind</span> David T. Sodaitis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>Shock Acceleration of the Energetic Particle Background in the <span class="hlt">Solar</span> <span class="hlt">Wind</span> David T. Sodaitis Physics the Lee (1983) theory. 1. Introduction to the <span class="hlt">Solar</span> <span class="hlt">Wind</span> The <span class="hlt">solar</span> <span class="hlt">wind</span> consists of a stream of ions greater than the restraining force of gravity, the <span class="hlt">solar</span> <span class="hlt">wind</span> is driven outward. For those of us residing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.am.ub.es/~blai/articles/10LarioEtR_AIP.pdf','EPRINT'); return false;" href="http://www.am.ub.es/~blai/articles/10LarioEtR_AIP.pdf"><span id="translatedtitle">Radial Heliospheric Magnetic Fields in <span class="hlt">Solar</span> <span class="hlt">Wind</span> Rarefaction Regions: Ulysses Observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Sanahuja, Blai</p> <p></p> <p>Radial Heliospheric Magnetic Fields in <span class="hlt">Solar</span> <span class="hlt">Wind</span> Rarefaction Regions: Ulysses Observations D it observed <span class="hlt">solar</span> <span class="hlt">wind</span> shears from the incursions of high-latitude fast <span class="hlt">solar</span> <span class="hlt">wind</span> toward the low-latitude slow <span class="hlt">solar</span> <span class="hlt">wind</span>. We look for nearly radial field orientations commonly observed in rarefaction regions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://lasp.colorado.edu/~lix/paper/GRL/grl96.camera.pdf','EPRINT'); return false;" href="http://lasp.colorado.edu/~lix/paper/GRL/grl96.camera.pdf"><span id="translatedtitle">Are energetic electrons in the <span class="hlt">solar</span> <span class="hlt">wind</span> the source of the outer radiation belt?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Li, Xinlin</p> <p></p> <p>Are energetic electrons in the <span class="hlt">solar</span> <span class="hlt">wind</span> the source of the outer radiation belt? Xinlin Li,1 D. N. Mewaldt6 Abstract. Using data from <span class="hlt">WIND</span>, SAMPEX (<span class="hlt">Solar</span>, Anomalous, and Magnetospheric Particle Explorer the correlation of en- ergetic electrons in the 20-200 keV range in the <span class="hlt">solar</span> <span class="hlt">wind</span> and of high speed <span class="hlt">solar</span> <span class="hlt">wind</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/cism/papers/Arge03.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/cism/papers/Arge03.pdf"><span id="translatedtitle">Improved Method for Specifying <span class="hlt">Solar</span> <span class="hlt">Wind</span> Speed Near the Sun Charles N. Arge*</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>Improved Method for Specifying <span class="hlt">Solar</span> <span class="hlt">Wind</span> Speed Near the Sun Charles N. Arge* , Dusan Odstrcil <span class="hlt">solar</span> <span class="hlt">wind</span> flow speed near the Sun (~0.1 AU) us- ing a set of three simple inter-linked coronal/<span class="hlt">solar</span> <span class="hlt">wind</span> models. In addition to magnetic field expansion factor, <span class="hlt">solar</span> <span class="hlt">wind</span> speed also appears</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.454.3697M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.454.3697M"><span id="translatedtitle">Alfvén wave <span class="hlt">solar</span> model (AWSoM): proton temperature anisotropy and <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meng, X.; van der Holst, B.; Tóth, G.; Gombosi, T. I.</p> <p>2015-12-01</p> <p>Temperature anisotropy has been frequently observed in the <span class="hlt">solar</span> corona and the <span class="hlt">solar</span> <span class="hlt">wind</span>, yet poorly represented in computational models of the <span class="hlt">solar</span> <span class="hlt">wind</span>. Therefore, we have included proton temperature anisotropy in our Alfvén wave <span class="hlt">solar</span> model (AWSoM). This model solves the magnetohydrodynamic equations augmented with low-frequency Alfvén wave turbulence. The wave reflection due to Alfvén speed gradient and field-aligned vorticity results in turbulent cascade. At the gyroradius scales, the apportioning of the turbulence dissipation into coronal heating of the protons and electrons is through stochastic heating. This paper focuses on the impacts of the proton temperature anisotropy on the <span class="hlt">solar</span> <span class="hlt">wind</span>. We apply AWSoM to simulate the steady <span class="hlt">solar</span> <span class="hlt">wind</span> from the corona to 1 AU using synoptic magnetograms. The Alfvén wave energy density at the inner boundary is prescribed with a uniform Poynting flux per field strength. We present the proton temperature anisotropy distribution, and investigate the firehose instability in the heliosphere from our simulations. In particular, the comparisons between the simulated and observed <span class="hlt">solar</span> <span class="hlt">wind</span> properties at 1 AU during the ramping-up phase and the maximum of <span class="hlt">solar</span> cycle 24 imply the importance of addressing the proton temperature anisotropy in <span class="hlt">solar</span> <span class="hlt">wind</span> modelling to capture the fast <span class="hlt">solar</span> <span class="hlt">wind</span> speed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E3124S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E3124S"><span id="translatedtitle">Transient flows of the <span class="hlt">solar</span> <span class="hlt">wind</span> associated with small-scale <span class="hlt">solar</span> activity in <span class="hlt">solar</span> minimum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Slemzin, Vladimir; Veselovsky, Igor; Kuzin, Sergey; Gburek, Szymon; Ulyanov, Artyom; Kirichenko, Alexey; Shugay, Yulia; Goryaev, Farid</p> <p></p> <p>The data obtained by the modern high sensitive EUV-XUV telescopes and photometers such as CORONAS-Photon/TESIS and SPHINX, STEREO/EUVI, PROBA2/SWAP, SDO/AIA provide good possibilities for studying small-scale <span class="hlt">solar</span> activity (SSA), which is supposed to play an important role in heating of the corona and producing transient flows of the <span class="hlt">solar</span> <span class="hlt">wind</span>. During the recent unusually weak <span class="hlt">solar</span> minimum, a large number of SSA events, such as week <span class="hlt">solar</span> flares, small CMEs and CME-like flows were observed and recorded in the databases of flares (STEREO, SWAP, SPHINX) and CMEs (LASCO, CACTUS). On the other hand, the <span class="hlt">solar</span> <span class="hlt">wind</span> data obtained in this period by ACE, <span class="hlt">Wind</span>, STEREO contain signatures of transient ICME-like structures which have shorter duration (<10h), weaker magnetic field strength (<10 nT) and lower proton temperature than usual ICMEs. To verify the assumption that ICME-like transients may be associated with the SSA events we investigated the number of weak flares of C-class and lower detected by SPHINX in 2009 and STEREO/EUVI in 2010. The flares were classified on temperature and emission measure using the diagnostic means of SPHINX and Hinode/EIS and were confronted with the parameters of the <span class="hlt">solar</span> <span class="hlt">wind</span> (velocity, density, ion composition and temperature, magnetic field, pitch angle distribution of the suprathermal electrons). The outflows of plasma associated with the flares were identified by their coronal signatures - CMEs (only in few cases) and dimmings. It was found that the mean parameters of the <span class="hlt">solar</span> <span class="hlt">wind</span> projected to the source surface for the times of the studied flares were typical for the ICME-like transients. The results support the suggestion that weak flares can be indicators of sources of transient plasma flows contributing to the slow <span class="hlt">solar</span> <span class="hlt">wind</span> at <span class="hlt">solar</span> minimum, although these flows may be too weak to be considered as separate CMEs and ICMEs. The research leading to these results has received funding from the European Union’s Seventh Programme for Research, Technological Development and Demonstration under Grant Agreement “eHeroes” (project n° 284461, www.eheroes.eu).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19870007250&hterms=technologie&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dtechnologie','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19870007250&hterms=technologie&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dtechnologie"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span>-plasma interaction: The AMPTE <span class="hlt">solar</span> <span class="hlt">wind</span> plasma releases</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1986-01-01</p> <p>In situ measurements during AMPTE <span class="hlt">solar</span> <span class="hlt">wind</span> ion releases are described. The creation of a diamagnetic cavity, compression and draping of magnetic field lines, recoil of the entire artificial comet, and ion beam and tail formation are discussed. The wave measurements were used to determine the time variation of the plasma density from the measurement of the electron plasma frequency and to determine the state of cloud expansion and cavity formation. Features found include absence of strong turbulence and anomalous diffusion in the cavity boundary, and the appearance of very intense shock-like emission in front of the plasma clouds. The first effect suggests partially unknowm processes leading to magnetic field penetration into the region of the clouds. The direct observation of the interaction processes between the fast streaming <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and the expanding cloud plasma of the Li and artificial comet releases may have relevance to astrophysical situations as, for instance, encountered in <span class="hlt">solar</span> flares, interstellar clouds, or during accretion of matter onto compact objects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19910047213&hterms=rate+erosion&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Drate%2Berosion','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19910047213&hterms=rate+erosion&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Drate%2Berosion"><span id="translatedtitle">Erosion of carbon/carbon by <span class="hlt">solar</span> <span class="hlt">wind</span> charged particle radiation during a <span class="hlt">solar</span> probe mission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sokolowski, Witold; O'Donnell, Tim; Millard, Jerry</p> <p>1991-01-01</p> <p>The possible erosion of a carbon/carbon thermal shield by <span class="hlt">solar</span> <span class="hlt">wind</span>-charged particle radiation is reviewed. The present knowledge of erosion data for carbon and/or graphite is surveyed, and an explanation of erosion mechanisms under different charged particle environments is discussed. The highest erosion is expected at four <span class="hlt">solar</span> radii. Erosion rates are analytically estimated under several conservative assumptions for a normal quiet and worst case <span class="hlt">solar</span> <span class="hlt">wind</span> storm conditions. Mass loss analyses and comparison studies surprisingly indicate that the predicted erosion rate by <span class="hlt">solar</span> <span class="hlt">wind</span> could be greater than by nominal free sublimation during <span class="hlt">solar</span> <span class="hlt">wind</span> storm conditions at four <span class="hlt">solar</span> radii. The predicted overall mass loss of a carbon/carbon shield material during the critical four <span class="hlt">solar</span> radii flyby can still meet the mass loss mission requirement of less than 0.0025 g/sec.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/112936','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/112936"><span id="translatedtitle">He abundance variations in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Observations from Ulysses</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Barraclough, B.L.; Gosling, J.T.; Phillips, J.L.; McComas, D.J.; Feldman, W.C.; Goldstein, B.E.</p> <p>1995-09-01</p> <p>The Ulysses mission is providing the first opportunity to observe variations in <span class="hlt">solar</span> <span class="hlt">wind</span> plasma parameters at heliographic latitudes far removed from the ecliptic plane. We present an overview of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed and the variability in helium abundance, [He] data on [He] in six high latitude coronal mass ejections (CMEs), and a superposed epoch analysis of [He] variations at the seven heliospheric current sheet (HCS) crossings made during the rapid-latitude-scan portion of the mission. The differences in the variability of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed and [He] in high latitude and equatorial regions are quite striking. <span class="hlt">Solar</span> <span class="hlt">wind</span> speed is generally low but highly variable near the <span class="hlt">solar</span> equator, while at higher latitudes the average speed is quite high with little variability. [He] can vary over nearly two decades at low <span class="hlt">solar</span> latitudes, while at high latitudes it varies only slightly. In contrast to the high [He] that is commonly associated with CMEs observed in the ecliptic, none of the six high-speed CMEs encountered at high southern heliographic latitudes showed any significant variation in helium content. A superposed epoch analysis of the [He] during all seven HCS crossings made as Ulysses passed from the southern to northern <span class="hlt">solar</span> hemisphere shows the expected [He] minimum near the crossing and a broad region of low [He] around the crossing time. We discuss how our <span class="hlt">solar</span> <span class="hlt">wind</span> [He] observations may provide an accurate measure of the helium composition for the entire convective zone of the Sun.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRA..120.8177A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRA..120.8177A"><span id="translatedtitle">Electron energetics in the expanding <span class="hlt">solar</span> <span class="hlt">wind</span> via Helios observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Å tverák, Å. t?pán.; Trávní?ek, Pavel M.; Hellinger, Petr</p> <p>2015-10-01</p> <p>We present an observational analysis of electron cooling/heating rates in the fast and slow <span class="hlt">solar</span> <span class="hlt">wind</span> between 0.3 and 1 AU. We fit electron velocity distribution functions acquired in situ by Helios 1 and 2 spacecraft by a three-component (core-halo-strahl) analytical model. The resulting radial profiles of macroscopic characteristics (density, temperatures, and heat fluxes) are employed to examine properties of theoretical energy balance equations and to estimate external cooling/heating terms. Our analysis indicates that in contrast to <span class="hlt">solar</span> <span class="hlt">wind</span> protons the electrons do not require important heating mechanisms to explain the observed temperature gradients. The electron heating rates are actually found to be negative for both the slow and fast <span class="hlt">solar</span> <span class="hlt">wind</span>, namely, due to the significant degradation of the electron heat flux with increasing radial distance from the Sun. Cooling mechanisms acting on electrons are found to be significantly stronger in the slow <span class="hlt">wind</span> than in the fast <span class="hlt">wind</span> streams.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSH11C..05P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSH11C..05P"><span id="translatedtitle">Measurements of Core Electron Heating in <span class="hlt">Solar</span> <span class="hlt">Wind</span> Reconnection Exhausts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pulupa, M.; Salem, C. S.; Phan, T.; Bale, S. D.; Gosling, J. T.</p> <p>2013-12-01</p> <p>Using electron measurements from the <span class="hlt">Wind</span>/3DP Electron Electrostatic Analyzer and thermal noise spectra from the <span class="hlt">Wind</span>/WAVES Thermal Noise Receiver, we have developed a technique which (a) corrects electron distribution functions for spacecraft potential and (b) isolates and fits the thermal core electron population in the <span class="hlt">solar</span> <span class="hlt">wind</span>. From these fits, we can accurately determine the rate of core electron heating during <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection exhausts. We present several examples of observed reconnection events, showing that core electron heating occurs within some exhaust regions but is absent in other events. These examples serve as the starting point for a statistical study, which will determine the dependence of electron heating on exhaust region boundary conditions and <span class="hlt">solar</span> <span class="hlt">wind</span> plasma parameters. Results from this study will be compared to recent results from the magnetopause, in an effort to establish a universal relationship between reconnection exhaust parameters and electron heating.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1094881','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1094881"><span id="translatedtitle">Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study: Phase 2 (Presentation)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lew, D.; Brinkman, G.; Ibanez, E.; Lefton, S.; Kumar, N.; Venkataraman, S.; Jordan, G.</p> <p>2013-09-01</p> <p>This presentation summarizes the scope and results of the Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study Phase 2, which examined operational impacts of high penetrations of variable renewable generation in the West.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSH13C4131Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSH13C4131Y"><span id="translatedtitle">On the Dynamic Character of the Polar <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yu, H. S.; Jackson, B. V.; Hick, P. P.; Buffington, A.</p> <p>2014-12-01</p> <p>SOHO LASCO C2 and STEREO SECCHI COR 2 coronagraph images, when analyzed using correlation tracking techniques, show a surprising result in polar coronal hole regions ordinarily thought of as "quiet" <span class="hlt">solar</span> <span class="hlt">wind</span>. Here what we observe is not the static well-ordered flow and gradual acceleration expected of quiescent regions. Rather, the coronagraph images show outflow in polar coronal holes as intermittent, highly-variable <span class="hlt">solar</span> <span class="hlt">wind</span> speed structures. We compare measurements of these structures in different simultaneously-measured coronagraph images, and with coronal brightness. The distribution of structure speeds shows a gradual decrease with speed in the overlap regions of the two coronagraphs. Measurements of the mean speed derived versus height shows the <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration with position angle, and are compared with mass flux and other determinations of <span class="hlt">solar</span> <span class="hlt">wind</span> outflow over the large polar coronal hole regions. In this presentation we give the most recent work on this ongoing analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.boulder.swri.edu/pkb/ssr/ssr-swap.pdf','EPRINT'); return false;" href="http://www.boulder.swri.edu/pkb/ssr/ssr-swap.pdf"><span id="translatedtitle">The <span class="hlt">Solar</span> <span class="hlt">Wind</span> Around Pluto (SWAP) Instrument Aboard New Horizons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Stern, S. Alan</p> <p></p> <p>-ion measurements at all rotation angles as the New Horizons spacecraft scans to image Pluto and Charon during and Charon and in searching for magnetic fields of Pluto and Charon. As the <span class="hlt">solar</span> <span class="hlt">wind</span> approaches Pluto</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1094889','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1094889"><span id="translatedtitle">Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study Phase 2 (Fact Sheet)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>2013-09-01</p> <p>This is one-page, two-sided fact sheet presents high-level summary results of the Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study Phase 2, which examined operational impacts of high penetrations of variable renewable generation in the West.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19890054328&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsolar%2Bwind%2Benergy','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19890054328&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsolar%2Bwind%2Benergy"><span id="translatedtitle">Electrodynamics of <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere-ionosphere interactions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kan, Joseph R.; Akasofu, Syun-Ichi</p> <p>1989-01-01</p> <p>The paper presents a coherent picture of fundamental physical processes in three basic elements of the <span class="hlt">solar-wind</span>/magnetosphere/ionosphere coupling system: (1) the field-aligned potential structure which leads to the formation of auroral arcs, (2) the magnetosphere-ionosphere coupling which leads to the onset of magnetospheric substorms, and (3) the <span class="hlt">solar-wind</span>/magnetosphere dynamo which supplies the power driving various magnetospheric processes. Process (1) is forced into existence by the loss-cone constriction effect when the upward field-aligned current density exceeds the loss-cone thermal flux limit. Substorm onset occurs when the ionosphere responds fully to the enhanced magnetospheric convection driven by the <span class="hlt">solar</span> <span class="hlt">wind</span>. Energy is transferred from the <span class="hlt">solar</span> <span class="hlt">wind</span> to the magnetosphere by a dynamo process, primarily on open field lines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19840065464&hterms=collective&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcollective','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19840065464&hterms=collective&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcollective"><span id="translatedtitle">Collective capture of released lithium ions in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Winske, D.; Wu, C. S.; Li, Y. Y.; Zhou, G. C.</p> <p>1984-01-01</p> <p>The capture of newly ionized lithium ions in the <span class="hlt">solar</span> <span class="hlt">wind</span> by means of electromagnetic instabilities is investigated through linear analysis and computer simulation. Three instabilities, driven by a lithium velocity ring perpendicular to and drifting along the magnetic field, are considered. The capture time of the lithium by the <span class="hlt">solar</span> <span class="hlt">wind</span> is roughly 10 linear growth times, regardless of whether resonant or nonresonant modes dominate initially. Possible implications of the results for the Active Magnetosphere Particle Tracer Explorer (AMPTE) mission are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750011027','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750011027"><span id="translatedtitle">Interplanetary stream magnetism: Kinematic effects. [<span class="hlt">solar</span> magnetic fields and <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burlaga, L. F.; Barouch, E.</p> <p>1974-01-01</p> <p>The particle density, and the magnetic field intensity and direction are calculated in corotating streams of the <span class="hlt">solar</span> <span class="hlt">wind</span>, assuming that the <span class="hlt">solar</span> <span class="hlt">wind</span> velocity is constant and radial and that its azimuthal variations are not two rapid. The effects of the radial velocity profile in corotating streams on the magnetic fields were examined using kinematic approximation and a variety of field configurations on the inner boundary. Kinematic and dynamic effects are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRA..118...45B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRA..118...45B"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> forcing at Mercury: WSA-ENLIL model results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baker, Daniel N.; Poh, Gangkai; Odstrcil, Dusan; Arge, C. Nick; Benna, Mehdi; Johnson, Catherine L.; Korth, Haje; Gershman, Daniel J.; Ho, George C.; McClintock, William E.; Cassidy, Timothy A.; Merkel, Aimee; Raines, Jim M.; Schriver, David; Slavin, James A.; Solomon, Sean C.; TráVní?Ek, Pavel M.; Winslow, Reka M.; Zurbuchen, Thomas H.</p> <p>2013-01-01</p> <p>Analysis and interpretation of observations from the MESSENGER spacecraft in orbit about Mercury require knowledge of <span class="hlt">solar</span> <span class="hlt">wind</span> "forcing" parameters. We have utilized the Wang-Sheeley-Arge (WSA)-ENLIL <span class="hlt">solar</span> <span class="hlt">wind</span> modeling tool in order to calculate the values of interplanetary magnetic field (IMF) strength (B), <span class="hlt">solar</span> <span class="hlt">wind</span> velocity (V) and density (n), ram pressure (~nV2), cross-magnetosphere electric field (V × B), Alfvén Mach number (MA), and other derived quantities of relevance for <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere interactions. We have compared upstream MESSENGER IMF and <span class="hlt">solar</span> <span class="hlt">wind</span> measurements to see how well the ENLIL model results compare. Such parameters as <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure are key for determining the Mercury magnetopause standoff distance, for example. We also use the relatively high-time-resolution B-field data from MESSENGER to estimate the strength of the product of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed and southward IMF strength (Bs) at Mercury. This product VBs is the electric field that drives many magnetospheric dynamical processes and can be compared with the occurrence of energetic particle bursts within the Mercury magnetosphere. This quantity also serves as input to the global magnetohydrodynamic and kinetic magnetosphere models that are being used to explore magnetospheric and exospheric processes at Mercury. Moreover, this modeling can help assess near-real-time magnetospheric behavior for MESSENGER or other mission analysis and/or ground-based observational campaigns. We demonstrate that this <span class="hlt">solar</span> <span class="hlt">wind</span> forcing tool is a crucial step toward bringing heliospheric science expertise to bear on planetary exploration programs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EPSC....9..529V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EPSC....9..529V"><span id="translatedtitle">Jupiter's Magnetospheric Dynamics: Evidence of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Driving?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vogt, M. F.; Bunce, E. J.; Kronberg, E. A.</p> <p>2014-04-01</p> <p>Jupiter's magnetosphere is a highly dynamic environment. Analysis of magnetic field and particle measurements collected by the Galileo spacecraft in Jupiter's magnetotail has shown evidence of hundreds of reconnection events [3,7]. It has long been suggested that Jupiter's magnetospheric dynamics are controlled primarily by rotational stresses, rather than by the <span class="hlt">solar</span> <span class="hlt">wind</span>, due to the rapid planetary rotation period and large spatial scales [6]. Such an internally-driven mass loading and release process is expected to occur with a typical 2-4 day recurrence period. Quasi-periodic behavior, suggestive of reconnection, has been observed on a similar time scale intermittently in several data sets, including magnetic field dipolarizations, flow bursts, and the hectometric radio emissions [4,5]. However, several questions remain unanswered, including why some specific spacecraft orbits were particularly dynamic (such as Galileo orbits G2 and G8), why the periodicity is not always observed, and why the characteristic time scale varies from ~1 to 7 days when the periodicity is present. One possible explanation is that the periodic magnetospheric reconfigurations may be modulated by the <span class="hlt">solar</span> <span class="hlt">wind</span>, as seen in global MHD simulations of plasmoid release and other dynamics in the magnetospheres of both Jupiter and Saturn [1,2]. In this study we use the Michigan mSWiM propagated <span class="hlt">solar</span> <span class="hlt">wind</span> MHD model to estimate the <span class="hlt">solar</span> <span class="hlt">wind</span> conditions upstream of Jupiter. We make use of event association tests to determine whether there is a statistical link between Jovian reconnection events and <span class="hlt">solar</span> <span class="hlt">wind</span> compressions or other disturbed <span class="hlt">solar</span> <span class="hlt">wind</span> conditions. We also consider the possibility that varying <span class="hlt">solar</span> <span class="hlt">wind</span> conditions may alter the characteristic periodicity in Jupiter's magnetosphere. For example, we perform a Lomb periodogram analysis on the <span class="hlt">solar</span> <span class="hlt">wind</span> model data during both quiet intervals and intervals when quasi-periodic behavior is observed in the in situ magnetospheric data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840024844','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840024844"><span id="translatedtitle"><span class="hlt">Wind</span> loading on <span class="hlt">solar</span> concentrators: Some general considerations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Roschke, E. J.</p> <p>1984-01-01</p> <p>A survey was completed to examine the problems and complications arising from <span class="hlt">wind</span> loading on <span class="hlt">solar</span> concentrators. <span class="hlt">Wind</span> loading is site specific and has an important bearing on the design, cost, performance, operation and maintenance, safety, survival, and replacement of <span class="hlt">solar</span> collecting systems. Emphasis herein is on paraboloidal, two-axis tracking systems. Thermal receiver problems also are discussed. <span class="hlt">Wind</span> characteristics are discussed from a general point of view. Current methods for determining design <span class="hlt">wind</span> speed are reviewed. Aerodynamic coefficients are defined and illustrative examples are presented. <span class="hlt">Wind</span> tunnel testing is discussed, and environmental <span class="hlt">wind</span> tunnels are reviewed. Recent results on heliostat arrays are reviewed as well. Aeroelasticity in relation to structural design is discussed briefly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.P43D1952M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.P43D1952M"><span id="translatedtitle">Laboratory Investigations of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Sputtering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McLain, J. L.; Keller, J. W.; Farrell, W. M.</p> <p>2012-12-01</p> <p>Ion scattering spectrometric measurements will be presented on energetic neutral atoms (ENAs) reflecting from lunar regolith simulates. Mass selected H+ and He2+ pulsed ion beams were used to simulate the <span class="hlt">solar</span> <span class="hlt">wind</span> impacting a solid target. A low energy ion, 0.5 to 5 keV, impacting a surface loses energy by ionization, secondary electron emission, excitation, and potential sputtering. When the straggling of low energy ions impacting a surface becomes comparable to the penetration depth, backscattering of ions and ENAs can occur. This backscattering varies as a function of the incident ion angle. An increase in the neutral sputtering yield can occur at angles >60° due to the forward direction of the secondary cascade. Therefore, surface roughness plays a major role in the backscattering angle and energy distribution. The regolith of airless bodies is very rough on the microscopic scale which can lead to transmission of the incident ion through the grains and possible adsorption of the ejecta onto neighboring surfaces. These effects as well as target temperature, porosity, grain size and hydrogen implantation will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110005629','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110005629"><span id="translatedtitle">Dissipation of Turbulence in the <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goldstein, Melvyn L.</p> <p>2010-01-01</p> <p>I will describe the first three-dimensional (3-D) dispersion relations and wavenumber spectra of magnetic turbulence in the <span class="hlt">solar</span> <span class="hlt">wind</span> at sub-proton scales. The analysis takes advantage of the short separations of the Cluster spacecraft (d/sim approx.200 km) to apply the {it k}-filtering technique to the frequency range where the transition to sub-proton scales occurs. The dispersion diagrams show unambiguously that the cascade is carried by highly oblique Kinetic Alfven Wave with \\omega\\leq 0.1\\omega_{ci} in the plasma rest frame down to k_\\perp\\rho_i \\sim 2. The wavenumber spectra in the direction perpendicular to the mean magnetic field consists of two ranges of scales separated by a breakpoint in the interval [0.4,1] k_\\perp \\rho_i. Above the breakpoint, the spectra follow the Kolmogorov scaling k_\\perp^{-1.7}, consistent with existing theoretical predictions. Below the breakpoint, the spectra steepen to \\sim k_\\perp^{-4.5}. We conjecture that the turbulence undergoes a {\\it transition-range}, where part of energy is dissipated into proton heating via Landau damping, and the remaining energy cascades down to electron scales where electron Landau damping may predominate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/964607','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/964607"><span id="translatedtitle">Potential for Development of <span class="hlt">Solar</span> and <span class="hlt">Wind</span> Resource in Bhutan</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gilman, P.; Cowlin, S.; Heimiller, D.</p> <p>2009-09-01</p> <p>With support from the U.S. Agency for International Development (USAID), the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) produced maps and data of the <span class="hlt">wind</span> and <span class="hlt">solar</span> resources in Bhutan. The <span class="hlt">solar</span> resource data show that Bhutan has an adequate resource for flat-plate collectors, with annual average values of global horizontal <span class="hlt">solar</span> radiation ranging from 4.0 to 5.5 kWh/m2-day (4.0 to 5.5 peak sun hours per day). The information provided in this report may be of use to energy planners in Bhutan involved in developing energy policy or planning <span class="hlt">wind</span> and <span class="hlt">solar</span> projects, and to energy analysts around the world interested in gaining an understanding of Bhutan's <span class="hlt">wind</span> and <span class="hlt">solar</span> energy potential.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22364988','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22364988"><span id="translatedtitle">The dynamic character of the polar <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jackson, B. V.; Yu, H.-S.; Buffington, A.; Hick, P. P. E-mail: hsyu@ucsd.edu E-mail: pphick@ucsd.edu</p> <p>2014-09-20</p> <p>The <span class="hlt">Solar</span> and Heliospheric Observatory (SOHO) Large Angle and Spectrometric Coronagraph C2 and <span class="hlt">Solar</span> Terrestrial Relations Observatory (STEREO) COR2A coronagraph images, when analyzed using correlation tracking techniques, show a surprising result in places ordinarily thought of as 'quiet' <span class="hlt">solar</span> <span class="hlt">wind</span> above the poles in coronal hole regions. Instead of the static well-ordered flow and gradual acceleration normally expected, coronagraph images show outflow in polar coronal holes consisting of a mixture of intermittent slow and fast patches of material. We compare measurements of this highly variable <span class="hlt">solar</span> <span class="hlt">wind</span> from C2 and COR2A images and show that both coronagraphs measure essentially the same structures. Measurements of the mean velocity as a function of height of these structures are compared with mass flux determinations of the <span class="hlt">solar</span> <span class="hlt">wind</span> outflow in the large polar coronal hole regions and give similar results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110013339','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110013339"><span id="translatedtitle">The Character of the <span class="hlt">Solar</span> <span class="hlt">Wind</span>, Surface Interactions, and Water</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Farrell, William M.</p> <p>2011-01-01</p> <p>We discuss the key characteristics of the proton-rich <span class="hlt">solar</span> <span class="hlt">wind</span> and describe how it may interact with the lunar surface. We suggest that <span class="hlt">solar</span> <span class="hlt">wind</span> can be both a source and loss of water/OH related volatiles, and review models showing both possibilities. Energy from the Sun in the form of radiation and <span class="hlt">solar</span> <span class="hlt">wind</span> plasma are in constant interaction with the lunar surface. As such, there is a <span class="hlt">solar</span>-lunar energy connection, where <span class="hlt">solar</span> energy and matter are continually bombarding the lunar surface, acting at the largest scale to erode the surface at 0.2 Angstroms per year via ion sputtering [1]. Figure 1 illustrates this dynamically Sun-Moon system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5502783','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5502783"><span id="translatedtitle">Off-disk penetration of ancient <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sasaki, SHO )</p> <p>1991-05-01</p> <p>Following a suggestion by Wetherill (1981), an estimation is made of the capture of an ancient, intense <span class="hlt">solar</span> <span class="hlt">wind</span> by primordial dust. Because the mutual collision of planetesimals would generate additional dust grains in interplanetary space after the <span class="hlt">solar</span> nebula's dissipation, the vertical distribution of the dust is taken into account. The <span class="hlt">solar</span> <span class="hlt">wind</span> penetrates the dust swarm through the less opaque off-disk portions, explaining both the trapping of a substantial quantity of <span class="hlt">solar</span> <span class="hlt">wind</span> species and the high abundances of <span class="hlt">solar</span>-type noble gases in gas-rich meteorites and on Venus. The off-disk trap is efficient when the disk is opaque and its relative thickness does not diminish with increasing heliocentric distance. 34 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008A%26A...491....1R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008A%26A...491....1R"><span id="translatedtitle">Determining the LIC H density from the <span class="hlt">solar</span> <span class="hlt">wind</span> slowdown</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Richardson, J. D.; Liu, Y.; Wang, C.; McComas, D. J.</p> <p>2008-11-01</p> <p>Context: The ionized <span class="hlt">solar</span> <span class="hlt">wind</span> interacts directly with the interstellar neutrals which flow into the heliosphere. These neutrals are ionized, mainly by charge exchange, then accelerated to the <span class="hlt">solar</span> <span class="hlt">wind</span> speed with the momentum and energy removed from the bulk flow of the <span class="hlt">solar</span> <span class="hlt">wind</span>. Thus, by measuring the <span class="hlt">solar</span> <span class="hlt">wind</span> slowdown, one can estimate the interstellar neutral density. Aims: In July 2005, Ulysses at 5 AU and Voyager 2 near 80 AU were at the same heliolatitude. We use this alignment to determine the <span class="hlt">solar</span> <span class="hlt">wind</span> speed decrease between these two spacecraft. Methods: Ulysses data are used as input to a 1-D MHD model which includes the effects of pickup ions. We removed a section of data contaminated by an ICME directed toward Voyager 2. Results: Comparison of the Voyager 2 speeds with the model results shows that the <span class="hlt">solar</span> <span class="hlt">wind</span> speed decreased by 67 km s-1 between Ulysses and Voyager 2, consistent with an interstellar neutral density at the termination shock of 0.09 cm-3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSH51D4183K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSH51D4183K"><span id="translatedtitle">Asymptotic Theory of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Electron Halo Distribution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, S.; Yoon, P. H.</p> <p>2014-12-01</p> <p>The <span class="hlt">solar</span> <span class="hlt">wind</span> electrons are conveniently divided into core Maxwellian background, isotropic halo, and super-halo components (and some times, highly field-aligned strahl component, which can be considered as a fourth element). Recently, a theory was proposed that explains the origin of super-halo distribution. It was assumed that the super-halo distribution forms as a result of wave-particle interaction between the super-halo electron and steady-state Langmuir fluctuation known as the quasi-thermal noise. In the present paper, we discuss a theory of <span class="hlt">solar</span> <span class="hlt">wind</span> halo electron distribution. It is assumed that the <span class="hlt">solar</span> <span class="hlt">wind</span> electrons whose energy is intermediate to the Gaussian cold core and super-halo components can interact efficiently with the whistler turbulence, which is pervasively detected in the <span class="hlt">solar</span> <span class="hlt">wind</span> near 1 AU. By making use of Fokker-Planck particle kinetic equations for the electrons and the wave kinetic equation for the whistler waves, it is shown that the <span class="hlt">solar</span> <span class="hlt">wind</span> halo distribution emerges as an asymptotic steady-state solution. The figure shown below summarizes the theoretical reconstruction of the total <span class="hlt">solar</span> <span class="hlt">wind</span> electron velocity distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1051165','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1051165"><span id="translatedtitle">Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study Phase 2: Preprint</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lew, D.; Brinkman, G.; Ibanez, E.; Hodge, B.-M.; King, J.</p> <p>2012-09-01</p> <p>The Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study (WWSIS) investigates the impacts of high penetrations of <span class="hlt">wind</span> and <span class="hlt">solar</span> power into the Western Interconnection of the United States. WWSIS2 builds on the Phase 1 study but with far greater refinement in the level of data inputs and production simulation. It considers the differences between <span class="hlt">wind</span> and <span class="hlt">solar</span> power on systems operations. It considers mitigation options to accommodate <span class="hlt">wind</span> and <span class="hlt">solar</span> when full costs of wear-and-tear and full impacts of emissions rates are taken into account. It determines wear-and-tear costs and emissions impacts. New data sets were created for WWSIS2, and WWSIS1 data sets were refined to improve realism of plant output and forecasts. Four scenarios were defined for WWSIS2 that examine the differences between <span class="hlt">wind</span> and <span class="hlt">solar</span> and penetration level. Transmission was built out to bring resources to load. Statistical analysis was conducted to investigate <span class="hlt">wind</span> and <span class="hlt">solar</span> impacts at timescales ranging from seasonal down to 5 minutes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015175','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015175"><span id="translatedtitle">Sputtering by the <span class="hlt">Solar</span> <span class="hlt">Wind</span>: Effects of Variable Composition</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Killen, R. M.; Arrell, W. M.; Sarantos, M.; Delory, G. T.</p> <p>2011-01-01</p> <p>It has long been recognized that <span class="hlt">solar</span> <span class="hlt">wind</span> bombardment onto exposed surfaces in the <span class="hlt">solar</span> system will produce an energetic component to the exospheres about those bodies. Laboratory experiments have shown that there is no increase in the sputtering yield caused by highly charged heavy ions for metallic and for semiconducting surfaces, but the sputter yield can be noticeably increased in the case of a good insulating surface. Recently measurements of the <span class="hlt">solar</span> <span class="hlt">wind</span> composition have become available. It is now known that the <span class="hlt">solar</span> <span class="hlt">wind</span> composition is highly dependent on the origin of the particular plasma. Using the measured composition of the slow <span class="hlt">wind</span>, fast <span class="hlt">wind</span>, <span class="hlt">solar</span> energetic particle (SEP) population, and coronal mass ejection (CME), broken down into its various components, we have estimated the total sputter yield for each type of <span class="hlt">solar</span> <span class="hlt">wind</span>. Whereas many previous calculations of sputtering were limited to the effects of proton bombardment. we show that the heavy ion component. especially the He++ component. can greatly enhance the total sputter yield during times when the heavy ion population is enhanced. We will discuss sputtering of both neutrals and ions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSH23D..06J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSH23D..06J"><span id="translatedtitle">Properties of Suprathermal Ions in <span class="hlt">Solar</span> <span class="hlt">Wind</span> Compression Regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jensema, R. J.; Desai, M. I.; Broiles, T. W.; Mason, G. M.</p> <p>2014-12-01</p> <p>Corotating interaction regions (CIRs) or more generally <span class="hlt">solar</span> <span class="hlt">wind</span> compression regions are believed to draw their source material from persistent but highly dynamic population of suprathermal (ST) particles with energies from a few keV up to 100's of keV. Additionally, the suprathermal particle population is observed as an inverse power-law "tail" that smoothly connects to the thermal <span class="hlt">solar</span> <span class="hlt">wind</span>. Despite the prevalence of ST ions in interplanetary space, their origin is highly controversial primarily because many local and remote sources can contribute and cause large variations in tail properties such as intensity, density, spectral indices, and ion composition. Using <span class="hlt">solar</span> <span class="hlt">wind</span>, magnetic field, and suprathermal ion data (.02 -2 MeV/nuc) obtained by the <span class="hlt">Wind</span> spacecraft, we perform a comprehensive study of the properties of ST ion populations associated with compression regions observed near Earth orbit from 1994 to 2014. This continuous, multi-year dataset has provided us with measurements over nearly two <span class="hlt">solar</span> cycles (23 and 24) through differing <span class="hlt">solar</span> <span class="hlt">wind</span> and sunspot activity conditions. Our preliminary survey shows that the heavy ion spectral indices exhibit large variations on short (<1 year) and long (>1 year) timescales. We also investigate the relationships between the spectral indices, peak intensities, maximum energies, and various plasma properties such as compression ratios and <span class="hlt">solar</span> <span class="hlt">wind</span> speed changes, and use these statistical correlations to determine a set of new observational constraints for current acceleration models of suprathermal ions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4604519','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4604519"><span id="translatedtitle">Impacts of <span class="hlt">wind</span> stilling on <span class="hlt">solar</span> radiation variability in China</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lin, Changgui; Yang, Kun; Huang, Jianping; Tang, Wenjun; Qin, Jun; Niu, Xiaolei; Chen, Yingying; Chen, Deliang; Lu, Ning; Fu, Rong</p> <p>2015-01-01</p> <p><span class="hlt">Solar</span> dimming and <span class="hlt">wind</span> stilling (slowdown) are two outstanding climate changes occurred in China over the last four decades. The <span class="hlt">wind</span> stilling may have suppressed the dispersion of aerosols and amplified the impact of aerosol emission on <span class="hlt">solar</span> dimming. However, there is a lack of long-term aerosol monitoring and associated study in China to confirm this hypothesis. Here, long-term meteorological data at weather stations combined with short-term aerosol data were used to assess this hypothesis. It was found that surface <span class="hlt">solar</span> radiation (SSR) decreased considerably with <span class="hlt">wind</span> stilling in heavily polluted regions at a daily scale, indicating that <span class="hlt">wind</span> stilling can considerably amplify the aerosol extinction effect on SSR. A threshold value of 3.5?m/s for <span class="hlt">wind</span> speed is required to effectively reduce aerosols concentration. From this SSR dependence on <span class="hlt">wind</span> speed, we further derived proxies to quantify aerosol emission and <span class="hlt">wind</span> stilling amplification effects on SSR variations at a decadal scale. The results show that aerosol emission accounted for approximately 20% of the typical <span class="hlt">solar</span> dimming in China, which was amplified by approximately 20% by <span class="hlt">wind</span> stilling. PMID:26463748</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...515135L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...515135L"><span id="translatedtitle">Impacts of <span class="hlt">wind</span> stilling on <span class="hlt">solar</span> radiation variability in China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, Changgui; Yang, Kun; Huang, Jianping; Tang, Wenjun; Qin, Jun; Niu, Xiaolei; Chen, Yingying; Chen, Deliang; Lu, Ning; Fu, Rong</p> <p>2015-10-01</p> <p><span class="hlt">Solar</span> dimming and <span class="hlt">wind</span> stilling (slowdown) are two outstanding climate changes occurred in China over the last four decades. The <span class="hlt">wind</span> stilling may have suppressed the dispersion of aerosols and amplified the impact of aerosol emission on <span class="hlt">solar</span> dimming. However, there is a lack of long-term aerosol monitoring and associated study in China to confirm this hypothesis. Here, long-term meteorological data at weather stations combined with short-term aerosol data were used to assess this hypothesis. It was found that surface <span class="hlt">solar</span> radiation (SSR) decreased considerably with <span class="hlt">wind</span> stilling in heavily polluted regions at a daily scale, indicating that <span class="hlt">wind</span> stilling can considerably amplify the aerosol extinction effect on SSR. A threshold value of 3.5?m/s for <span class="hlt">wind</span> speed is required to effectively reduce aerosols concentration. From this SSR dependence on <span class="hlt">wind</span> speed, we further derived proxies to quantify aerosol emission and <span class="hlt">wind</span> stilling amplification effects on SSR variations at a decadal scale. The results show that aerosol emission accounted for approximately 20% of the typical <span class="hlt">solar</span> dimming in China, which was amplified by approximately 20% by <span class="hlt">wind</span> stilling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26463748','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26463748"><span id="translatedtitle">Impacts of <span class="hlt">wind</span> stilling on <span class="hlt">solar</span> radiation variability in China.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lin, Changgui; Yang, Kun; Huang, Jianping; Tang, Wenjun; Qin, Jun; Niu, Xiaolei; Chen, Yingying; Chen, Deliang; Lu, Ning; Fu, Rong</p> <p>2015-01-01</p> <p><span class="hlt">Solar</span> dimming and <span class="hlt">wind</span> stilling (slowdown) are two outstanding climate changes occurred in China over the last four decades. The <span class="hlt">wind</span> stilling may have suppressed the dispersion of aerosols and amplified the impact of aerosol emission on <span class="hlt">solar</span> dimming. However, there is a lack of long-term aerosol monitoring and associated study in China to confirm this hypothesis. Here, long-term meteorological data at weather stations combined with short-term aerosol data were used to assess this hypothesis. It was found that surface <span class="hlt">solar</span> radiation (SSR) decreased considerably with <span class="hlt">wind</span> stilling in heavily polluted regions at a daily scale, indicating that <span class="hlt">wind</span> stilling can considerably amplify the aerosol extinction effect on SSR. A threshold value of 3.5?m/s for <span class="hlt">wind</span> speed is required to effectively reduce aerosols concentration. From this SSR dependence on <span class="hlt">wind</span> speed, we further derived proxies to quantify aerosol emission and <span class="hlt">wind</span> stilling amplification effects on SSR variations at a decadal scale. The results show that aerosol emission accounted for approximately 20% of the typical <span class="hlt">solar</span> dimming in China, which was amplified by approximately 20% by <span class="hlt">wind</span> stilling. PMID:26463748</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020086296','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020086296"><span id="translatedtitle">Investigation of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Correlations and <span class="hlt">Solar</span> <span class="hlt">Wind</span> Modifications Near Earth by Multi-Spacecraft Observations: IMP 8, <span class="hlt">WIND</span> and INTERBALL-1</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Paularena, Karolen I.; Richardson, John D.; Zastenker, Georgy N.</p> <p>2002-01-01</p> <p>The foundation of this Project is use of the opportunity available during the ISTP (International <span class="hlt">Solar</span>-Terrestrial Physics) era to compare <span class="hlt">solar</span> <span class="hlt">wind</span> measurements obtained simultaneously by three spacecraft - IMP 8, <span class="hlt">WIND</span> and INTERBALL-1 at wide-separated points. Using these data allows us to study three important topics: (1) the size and dynamics of near-Earth mid-scale (with dimension about 1-10 million km) and small-scale (with dimension about 10-100 thousand km) <span class="hlt">solar</span> <span class="hlt">wind</span> structures; (2) the reliability of the common assumption that <span class="hlt">solar</span> <span class="hlt">wind</span> conditions at the upstream Lagrangian (L1) point accurately predict the conditions affecting Earth's magnetosphere; (3) modification of the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and magnetic field in the regions near the Earth magnetosphere, the foreshock and the magnetosheath. Our Project was dedicated to these problems. Our research has made substantial contributions to the field and has lead others to undertake similar work.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080022945','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080022945"><span id="translatedtitle">On the Relationship Between <span class="hlt">Solar</span> <span class="hlt">Wind</span> Speed, Geomagnetic Activity, and the <span class="hlt">Solar</span> Cycle Using Annual Values</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, Robert M.; Hathaway, David H.</p> <p>2008-01-01</p> <p>The aa index can be decomposed into two separate components: the leading sporadic component due to <span class="hlt">solar</span> activity as measured by sunspot number and the residual or recurrent component due to interplanetary disturbances, such as coronal holes. For the interval 1964-2006, a highly statistically important correlation (r = 0.749) is found between annual averages of the aa index and the <span class="hlt">solar</span> <span class="hlt">wind</span> speed (especially between the residual component of aa and the <span class="hlt">solar</span> <span class="hlt">wind</span> speed, r = 0.865). Because cyclic averages of aa (and the residual component) have trended upward during cycles 11-23, cyclic averages of <span class="hlt">solar</span> <span class="hlt">wind</span> speed are inferred to have also trended upward.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E.207B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E.207B"><span id="translatedtitle">Chandrayaan-1 results on the <span class="hlt">solar</span> <span class="hlt">wind</span> ion - regolith interaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barabash, Stas</p> <p></p> <p>Recently several missions (Kaguya, Chandrayaan-1, IBEX) revealed for the first time the complexity of the <span class="hlt">solar</span> <span class="hlt">wind</span> ions interaction with the lunar regolith. In this review we focus on the observations performed by the Chandrayaan-1 mission at the Moon but similar interaction processes take place on all airless bodies covered by regolith. Contrary to early assumptions the <span class="hlt">solar</span> <span class="hlt">wind</span> ions are not fully absorbed by the regolith but experience strong (10-20% of the impinging flux) backscattering. Only hydrogen was firmly identified. Helium for the helium enriched <span class="hlt">solar</span> <span class="hlt">wind</span> was detected only tentatively. The charge - state of the backscattered particles is mainly neutral. The fraction of H (+) varies strongly with the impinging <span class="hlt">solar</span> <span class="hlt">wind</span> velocity and constitutes 0.01 - 10% of the total backscattered flux. No H (-) ions were detected. The spectrum of the backscattered hydrogen is best-fitted by a Maxwellian distribution with a temperature of 40 - 160 eV linearly proportional to the <span class="hlt">solar</span> <span class="hlt">wind</span> velocity. The spectrum of the backscattered protons is also Maxwellian although shifted to a velocity some what smaller than the <span class="hlt">solar</span> <span class="hlt">wind</span> velocity. The scattering function of the neutrals is close to isotropic at large impinging angles (small <span class="hlt">solar</span> zenith angles) and becomes backward peaked at shallow impinging angles. The scattering function and energy spectra of the backscatters indicate that the <span class="hlt">solar</span> <span class="hlt">wind</span> protons experience multiple collisions with surfaces of individual grain when traveling in the inter-grain space. Why the reflection efficiency is so high in this case is a puzzle. The <span class="hlt">solar</span> <span class="hlt">wind</span> also causes sputtering of elements composing the regolith minerals. Only sputtered oxygen was identified although at levels lower than expected. Chandrayaan-1 results on the <span class="hlt">solar</span> <span class="hlt">wind</span> ion - regolith interaction still remain to be explained. The orbital measurements should be complemented by measurements from landers revealing the “ground true”. Further studies of the interaction physics are required not only for further development of ENA imaging of airless bodies but also for understanding space weathering, ion implantation processes, and impact of backscattering on the global <span class="hlt">solar</span> <span class="hlt">wind</span> - Moon interaction picture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021284&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bwind%2Benergy','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021284&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bwind%2Benergy"><span id="translatedtitle">Electron energy transport in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Ulysses observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scime, Earl; Gary, S. Peter; Phillips, J. L.; Corniileau-Wehrlin, N.; Solomon, J.</p> <p>1995-01-01</p> <p>The electron heat flux in the <span class="hlt">solar</span> <span class="hlt">wind</span> has been measured by the Ulysses <span class="hlt">solar</span> <span class="hlt">wind</span> plasma experiment in the ecliptic from 1 to 5 AU and out of the ecliptic during the recently completed pass over the <span class="hlt">solar</span> south pole and the ongoing pass over the <span class="hlt">solar</span> north pole. Although the electron heat flux contains only a fraction of the kinetic energy of the <span class="hlt">solar</span> <span class="hlt">wind</span>. the available energy is sufficient to account for the non-adiabatic expansion of the <span class="hlt">solar</span> <span class="hlt">wind</span> electrons. The Ulysses measurements indicate that the electron heat flux is actively dissipated in the <span class="hlt">solar</span> <span class="hlt">wind</span>. The exact mechanism or mechanisms is unknown. but a model based on the whistler heat flux instability predicts radial gradients for the electron heat flux in good agreement with the data. We will present measurements of the correlation between wave activity measured by the unified radio and plasma experiment (URAP) and the electron heat flux throughout the Ulysses mission. The goal is to determine if whistler waves are a good candidate for the observed electron heat flux dissipation. The latitudinal gradients of the electron heat flux. wave activity. and electron pressure will be discussed in light of the changes in the magnetic field geometry from equator to poles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014FrASS...1....4E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014FrASS...1....4E"><span id="translatedtitle">A survey of <span class="hlt">solar</span> <span class="hlt">wind</span> conditions at 5 AU: A tool for interpreting <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere interactions at Jupiter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ebert, Robert; Bagenal, Fran; McComas, David; Fowler, Christopher</p> <p>2014-09-01</p> <p>We examine Ulysses <span class="hlt">solar</span> <span class="hlt">wind</span> and interplanetary magnetic field (IMF) observations at 5 AU for two ~13 month intervals during the rising and declining phases of <span class="hlt">solar</span> cycle 23 and the predicted response of the Jovian magnetosphere during these times. The declining phase <span class="hlt">solar</span> <span class="hlt">wind</span>, composed primarily of corotating interaction regions and high-speed streams, was, on average, faster, hotter, less dense, and more Alfvénic relative to the rising phase <span class="hlt">solar</span> <span class="hlt">wind</span>, composed mainly of slow <span class="hlt">wind</span> and interplanetary coronal mass ejections. Interestingly, none of <span class="hlt">solar</span> <span class="hlt">wind</span> and IMF distributions reported here were bimodal, a feature used to explain the bimodal distribution of bow shock and magnetopause standoff distances observed at Jupiter. Instead, many of these distributions had extended, non-Gaussian tails that resulted in large standard deviations and much larger mean over median values. The distribution of predicted Jupiter bow shock and magnetopause standoff distances during these intervals were also not bimodal, the mean/median values being larger during the declining phase by ~1 - 4%. These results provide data-derived <span class="hlt">solar</span> <span class="hlt">wind</span> and IMF boundary conditions at 5 AU for models aimed at studying <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere interactions at Jupiter and can support the science investigations of upcoming Jupiter system missions. Here, we provide expectations for Juno, which is scheduled to arrive at Jupiter in July 2016. Accounting for the long-term decline in <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure reported by McComas et al. (2013), Jupiter’s bow shock and magnetopause is expected to be at least 8 - 12% further from Jupiter, if these trends continue.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015TESS....110805L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015TESS....110805L"><span id="translatedtitle">Element Abundances in the Sun and <span class="hlt">Solar</span> <span class="hlt">Wind</span> Along the <span class="hlt">Solar</span> Cycle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Landi, Enrico</p> <p>2015-04-01</p> <p>Element abundances are a critical parameter in almost every aspect of <span class="hlt">solar</span> physics, from regulating the energy flow and the structure of the <span class="hlt">solar</span> interior, to shaping the energy losses of the <span class="hlt">solar</span> atmosphere, ruling the radiative output of the UV, EUV and X-rays <span class="hlt">solar</span> radiation which impacts the Earth's upper atmosphere, and determining the composition of the <span class="hlt">solar</span> <span class="hlt">wind</span>.In this work we study the evolution of the element abundances in the <span class="hlt">solar</span> corona and in the <span class="hlt">solar</span> <span class="hlt">wind</span> from 1996 to date using data from SoHO, Hinode, Ulysses and ACE satellites, in order to determine their variability along the <span class="hlt">solar</span> cycle, and the relationship between <span class="hlt">solar</span> abundance variations in the <span class="hlt">solar</span> <span class="hlt">wind</span> and in its source regions in the <span class="hlt">solar</span> atmosphere. We study all the most abundant elements, with a special emphasis on Ne and O. We discuss our results in light of the source region of the <span class="hlt">solar</span> <span class="hlt">wind</span>, and of the radiative output of the <span class="hlt">solar</span> corona.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21371703','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21371703"><span id="translatedtitle">Velocity Distributions and Proton Beam Production in the <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pierrard, Viviane; Voitenko, Yuriy</p> <p>2010-03-25</p> <p>Helios, Ulysses, and <span class="hlt">Wind</span> spacecraft have observed the velocity distribution functions (VDFs) of <span class="hlt">solar</span> <span class="hlt">wind</span> particles deviating significantly from Maxwellians. We review recent models using different approximations and mechanisms that determine various observed characteristics of the VDFs for the electrons, protons and minor ions. A new generation mechanism is proposed for super-Alfvenic proton beams and tails that are often observed in the fast <span class="hlt">solar</span> <span class="hlt">wind</span>. The mechanism is based on the proton trapping and acceleration by kinetic Alfven waves (KAWs), which carry a field-aligned potential well propagating with super-Alfven velocities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021285&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsolar%2Bwaves','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021285&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsolar%2Bwaves"><span id="translatedtitle">Some remarks on waves in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kellogg, Paul J.</p> <p>1995-01-01</p> <p>Waves are significant to the <span class="hlt">solar</span> <span class="hlt">wind</span> in two ways as modifiers of the particle distribution functions, and as diagnostics. In addition, the <span class="hlt">solar</span> <span class="hlt">wind</span> serves as an important laboratory for the study of plasma wave processes, as it is possible to make detailed measurements of phenomena which are too small to be easily measured by laboratory sized sensors. There are two areas where waves (we include discontinuities under this heading) must make important modifications of the distribution functions: in accelerating the alpha particles to higher speeds than the protons (Marsch et al.) and in accelerating the <span class="hlt">solar</span> <span class="hlt">wind</span> itself. A third area is possibly in maintaining the relative isotropy of the <span class="hlt">solar</span> <span class="hlt">wind</span> ion distribution in the <span class="hlt">solar</span> <span class="hlt">wind</span> rest frame. As the <span class="hlt">solar</span> <span class="hlt">wind</span> is nearly collisionless, the ions should conserve magnetic moment in rushing out from the sun, and therefore Tperp/B should be relatively constant, but it is obviously not. This has not received much attention. The waves, both electromagnetic and electrostatic, which are pan of the <span class="hlt">solar</span> Type 111 burst phenomenon, have been extensively studied as examples of nonlinear plasma phenomena, and also used as remote sensors to trace the <span class="hlt">solar</span> magnetic field. The observations made by Ulysses show that the field can be traced in this way out to perhaps a little more than an A.U., but then the electromagnetic pan of the type 111 burst fades out. Nevertheless, sometimes Langmuir waves appear at Ulysses at an appropriate extrapolated time. This seems to support the picture in which the electromagnetic waves at the fundamental plasma frequency are trapped in density fluctuations. Langmuir waves in the <span class="hlt">solar</span> <span class="hlt">wind</span> are usually in quasi-thermal equilibrium quasi because the <span class="hlt">solar</span> <span class="hlt">wind</span> itself is not isothermal. The Observatory of Paris group (Steinberg. Meyer-Vernet, Hoang) has exploited this with an experiment on <span class="hlt">WIND</span> which is capable of providing density and temperature on a faster time scale than hitherto. Recently it has been found that Langmuir waves are associated with magnetic holes. This may help to elucidate the nature of magnetic holes. Nonlinear processes are important in the transformation of wave energy to panicle energy. Some recent examples from <span class="hlt">WIND</span> data will be shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19780050051&hterms=primary+source+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dprimary%2Bsource%2Bwind','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19780050051&hterms=primary+source+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dprimary%2Bsource%2Bwind"><span id="translatedtitle">Additional evidence consistent with <span class="hlt">solar</span> cycle variations in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Intriligator, D. S.</p> <p>1978-01-01</p> <p>Analyses of <span class="hlt">solar-wind</span> observations from mid-1964 through 1973 confirm the earlier results reported by Intriligator (1974) that there were statistically significant variations in the <span class="hlt">solar</span> <span class="hlt">wind</span> in 1968 and 1969, years of <span class="hlt">solar</span> maximum. These variations were in phase with the <span class="hlt">solar</span> cycle and consistent with a <span class="hlt">solar</span>-cycle variation in the <span class="hlt">solar</span> <span class="hlt">wind</span>. High-speed stream parameters show that the number of high-speed streams in the <span class="hlt">solar</span> <span class="hlt">wind</span> in 1968 and 1969 and the total duration (in days) of high-speed streams in 1968 were considerably more than the predicted yearly average, and in 1965 and 1972 considerably less. Histograms of <span class="hlt">solar-wind</span> speed from 1964 through 1973 indicate that in 1968 there was the highest percentage of elevated <span class="hlt">solar-wind</span> speeds, and in 1965 and 1972 the lowest. Studies by others confirm these results, although their authors did not indicate this fact. The duration of the streams and the histograms for 1973 may imply a shifting in the primary stream source.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...807...86S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...807...86S"><span id="translatedtitle">Self-consistent Castaing Distribution of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Turbulent Fluctuations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sorriso-Valvo, L.; Marino, R.; Lijoi, L.; Perri, S.; Carbone, V.</p> <p>2015-07-01</p> <p>The intermittent behavior of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulent fluctuations has often been investigated through the modeling of their probability distribution functions (PDFs). Among others, the Castaing model has successfully been used in the past. In this paper, the energy dissipation field of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence has been studied for fast, slow, and polar <span class="hlt">wind</span> samples recorded by Helios 2 and Ulysses spacecraft. The statistical description of the dissipation rate has then been used to remove intermittency through conditioning of the PDFs. Based on such observation, a self-consistent, parameter-free Castaing model is presented. The self-consistent model is tested against experimental PDFs, showing good agreement and supporting the picture of a multifractal energy cascade at the origin of <span class="hlt">solar</span> <span class="hlt">wind</span> intermittency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1505.07879.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1505.07879.pdf"><span id="translatedtitle">Self-consistent Castaing distribution of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulent fluctuations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Sorriso-Valvo, L; Lijoi, L; Perri, S; Carbone, V</p> <p>2015-01-01</p> <p>The intermittent behavior of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulent fluctuations has often been investigated through the modeling of their probability distribution functions (PDFs). Among others, the Castaing model (Castaing et al. 1990) has successfully been used in the past. In this paper, the energy dissipation field of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence has been studied for fast, slow and polar <span class="hlt">wind</span> samples recorded by Helios 2 and Ulysses spacecraft. The statistical description of the dissipation rate has then be used to remove intermittency through conditioning of the PDFs. Based on such observation, a self-consistent, parameter-free Castaing model is presented. The self-consistent model is tested against experimental PDFs, showing good agreement and supporting the picture of a multifractal energy cascade at the origin of <span class="hlt">solar</span> <span class="hlt">wind</span> intermittency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1511.09350.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1511.09350.pdf"><span id="translatedtitle">Modeling Jets in the Corona and <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Torok, T; Titov, V S; Leake, J E; Mikic, Z; Linker, J A; Linton, M G</p> <p>2015-01-01</p> <p>Coronal jets are transient, collimated eruptions that occur in regions of predominantly open magnetic field in the <span class="hlt">solar</span> corona. Our understanding of these events has greatly evolved in recent years but several open questions, such as the contribution of coronal jets to the <span class="hlt">solar</span> <span class="hlt">wind</span>, remain. Here we present an overview of the observations and numerical modeling of coronal jets, followed by a brief description of "next-generation" simulations that include an advanced description of the energy transfer in the corona ("thermodynamic MHD"), large spherical computational domains, and the <span class="hlt">solar</span> <span class="hlt">wind</span>. These new models will allow us to address some of the open questions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19730054131&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19730054131&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon"><span id="translatedtitle">Electric potential of the moon in the <span class="hlt">solar</span> <span class="hlt">wind</span>.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Freeman, J. W., Jr.; Fenner, M. A.; Hills, H. K.</p> <p>1973-01-01</p> <p>Acceleration and detection of the lunar thermal ionosphere in the presence of the lunar electric field yields a value of at least +10 V for the lunar electric potential for <span class="hlt">solar</span> zenith angles between approximately 20 and 45 deg and in the magnetosheath or <span class="hlt">solar</span> <span class="hlt">wind</span>. An enhanced positive ion flux is observed with the Apollo Lunar Surface Experiments Package Suprathermal Ion Detector Experiment when a preacceleration voltage attains certain values. This enhancement is greater when the moon is in the <span class="hlt">solar</span> <span class="hlt">wind</span> as opposed to the magnetosheath.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.P21C3918D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.P21C3918D"><span id="translatedtitle">Improving <span class="hlt">solar</span> <span class="hlt">wind</span> modeling at Mercury: Incorporating transient <span class="hlt">solar</span> phenomena into the WSA-ENLIL model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dewey, R. M.; Baker, D. N.; Anderson, B. J.; Benna, M.; Johnson, C. L.; Korth, H.; Gershman, D. J.; Ho, G. C.; McClintock, W. E.; Odstrcil, D.; Philpott, L. C.; Raines, J. M.; Schriver, D.; Slavin, J. A.; Solomon, S. C.; Winslow, R. M.; Zurbuchen, T.</p> <p>2014-12-01</p> <p>Coronal mass ejections (CMEs) and other transient <span class="hlt">solar</span> phenomena play important roles in magnetospheric and exospheric dynamics. Although a planet may only occasionally interact with the products of these events, such transient phenomena can result in departures from the background <span class="hlt">solar</span> <span class="hlt">wind</span> that often involve more than an order of magnitude greater ram pressure and interplanetary electric field applied to the magnetosphere. For Mercury, an order of magnitude greater ram pressure can push the magnetopause to the planet's surface, exposing the surface directly to the <span class="hlt">solar</span> <span class="hlt">wind</span>. In order to understand how the <span class="hlt">solar</span> <span class="hlt">wind</span> interacts with Mercury's magnetosphere and exosphere, previous studies have used the Wang-Sheeley-Arge (WSA)-ENLIL <span class="hlt">solar</span> <span class="hlt">wind</span> modeling tool to calculate basic and composite <span class="hlt">solar</span> <span class="hlt">wind</span> parameters, such as <span class="hlt">solar</span> <span class="hlt">wind</span> velocity (V) and Alfvén Mach number (MA) at Mercury's orbital location. This model forecasts only the background <span class="hlt">solar</span> <span class="hlt">wind</span>, however, and does not include these transient events. The Cone extension permits the inclusion of CMEs and other phenomena, and thus enables characterization of the effect of strong <span class="hlt">solar</span> <span class="hlt">wind</span> perturbations on the Mercury system. The Cone extension is predicated on the assumption of constant angular and radial velocities of ejecta to integrate them into the WSA-ENLIL coupled model. Comparisons of the model results with the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft observations indicate that the WSA-ENLIL-Cone model more accurately forecasts total <span class="hlt">solar</span> <span class="hlt">wind</span> conditions at Mercury and has greater predictive power for magnetospheric and exospheric processes than the WSA-ENLIL model alone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/419263','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/419263"><span id="translatedtitle">Ulysses <span class="hlt">solar</span> <span class="hlt">wind</span> plasma observations at high latitudes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Riley, P.; Bame, S.J.; Barraclough, B.L.</p> <p>1996-10-01</p> <p>Ulysses reached its peak northerly heliolatitude of 80.2{degrees}N on July 31, 1995, and now is moving towards aphelion at 5.41 AU which it will reach in May, 1998. We summarize measurements from the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma experiment, SWOOPS, emphasizing northern hemispheric observations but also providing southern and equatorial results for comparison. The <span class="hlt">solar</span> <span class="hlt">wind</span> momentum flux during Ulysses` fast pole-to- pole transit at <span class="hlt">solar</span> minimum was significantly higher over the poles than at near-equatorial latitudes, suggesting a non-circular cross section for the heliosphere. Furthermore, modest asymmetries in the <span class="hlt">wind</span> speed, density, and mass flux were observed between the two hemispheres during the fast latitude scan. The <span class="hlt">solar</span> <span class="hlt">wind</span> was faster and less dense in the north than in the south. These asymmetries persist in the most recent high- and mid-latitude data but are less pronounced. As of July 1, 1996 the northern fast <span class="hlt">solar</span> <span class="hlt">wind</span> has lacked any strong stream interactions or shocks and, although a comprehensive search has not yet been made, no CMEs have yet been identified during this interval. On the other hand, Alfv{acute e}nic, compressional, and pressure balanced features are abundant at high latitudes. The most recent data, at 4 AU and 32{degrees}N, has begun to show the effects of <span class="hlt">solar</span> rotation modulated features in the form of recurrent compressed regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22004277','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22004277"><span id="translatedtitle">CARBON IONIZATION STAGES AS A DIAGNOSTIC OF THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Landi, E.; Alexander, R. L.; Gruesbeck, J. R.; Gilbert, J. A.; Lepri, S. T.; Manchester, W. B.; Zurbuchen, T. H.</p> <p>2012-01-10</p> <p>Oxygen charge states measured by in situ instrumentation have long been used as a powerful diagnostic of the <span class="hlt">solar</span> corona and to discriminate between different <span class="hlt">solar</span> <span class="hlt">wind</span> regimes, both because they freeze in very close to the Sun, and because the oxygen element abundance is comparatively high, allowing for statistically relevant measures. Like oxygen, carbon is also rather abundant and freezes in very close to the Sun. Here, we show an analysis of carbon and oxygen ionic charge states. First, through auditory and Fourier analysis of in situ measurements of <span class="hlt">solar</span> <span class="hlt">wind</span> ion composition by ACE/SWICS we show that some carbon ion ratios are very sensitive to <span class="hlt">solar</span> <span class="hlt">wind</span> type, even more sensitive than the commonly used oxygen ion ratios. Then we study the evolution of the ionization states of carbon and oxygen by means of a freeze-in code, and find that carbon ions, commonly found in the <span class="hlt">solar</span> <span class="hlt">wind</span>, freeze in at comparable coronal distances, while oxygen ions evolve over a much larger range of coronal distances. Finally, we show that carbon and oxygen ion abundance ratios have similar sensitivity to the electron plasma temperature, but the carbon ratios are more robust against atomic physics uncertainties and a better indicator of the temperature of the <span class="hlt">solar</span> <span class="hlt">wind</span> source regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1507.03301.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1507.03301.pdf"><span id="translatedtitle">Relationship Between <span class="hlt">Solar</span> <span class="hlt">Wind</span> Speed and Coronal Magnetic Field Properties</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Fujiki, Ken'ichi; Iju, Tomoya; Hakamada, Kazuyuki; Kojima, Masayoshi</p> <p>2015-01-01</p> <p>We have studied the relationship between the <span class="hlt">solar-wind</span> speed $[V]$ and the coronal magnetic-field properties (a flux expansion factor [$f$] and photospheric magnetic-field strength [$B_{\\mathrm{S}}$]) at all latitudes using data of interplanetary scintillation and <span class="hlt">solar</span> magnetic field obtained for 24 years from 1986 to 2009. Using a cross-correlation analyses, we verified that $V$ is inversely proportional to $f$ and found that $V$ tends to increase with $B_{\\mathrm{S}}$ if $f$ is the same. As a consequence, we find that $V$ has extremely good linear correlation with $B_{\\mathrm{S}}/f$. However, this linear relation of $V$ and $B_{\\mathrm{S}}/f$ cannot be used for predicting the <span class="hlt">solar-wind</span> velocity without information on the <span class="hlt">solar-wind</span> mass flux. We discuss why the inverse relation between $V$ and $f$ has been successfully used for <span class="hlt">solar-wind</span> velocity prediction, even though it does not explicitly include the mass flux and magnetic-field strength, which are important physical parameters for <span class="hlt">solar-wind</span> accele...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.2004S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.2004S"><span id="translatedtitle">Results From The Genesis Autonomous <span class="hlt">Solar</span> <span class="hlt">Wind</span> Regime Algorithm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Steinberg, J. T.; Barraclough, B. L.; Dors, E. E.; Neugebauer, M.; Wiens, R. C.</p> <p></p> <p>Launched on August 8, 2001, the NASA Genesis mission is now collecting samples of the <span class="hlt">solar</span> <span class="hlt">wind</span> in various materials, and will return those samples to Earth for analysis in 2004. A primary science goal of Genesis is the determination of the elemental and isotopic composition of the <span class="hlt">solar</span> atmosphere from the <span class="hlt">solar</span> <span class="hlt">wind</span> material returned. Because the <span class="hlt">solar</span> <span class="hlt">wind</span> itself is known to exhibit compositional variations across dif- ferent types of <span class="hlt">solar</span> <span class="hlt">wind</span> flows, Genesis exposes different collectors to <span class="hlt">solar</span> <span class="hlt">wind</span> originating from three flow types: coronal hole (CH), coronal mass ejection (CME), and interstream (IS) flows. Flow types are identified using in situ measurements of so- lar <span class="hlt">wind</span> ions and electrons from electrostatic analyzers carried by Genesis. The flow regime selection algorithm and subsequent collector deployment on Genesis act au- tonomously. The algorithm takes into account the proton speed, proton temperature, alpha particle abundance, and the presence of counter-streaming suprathermal elec- trons as determined onboard. Autonomous determination of counter-streaming elec- trons is novel, as is the simultaneous utilization of electron information and ion mo- ments in logic that autonomously controls the science payload. Results to date show that <span class="hlt">solar</span> <span class="hlt">wind</span> has recently been dominated by IS flow with frequent CMEs. Between 24 August 2001 and 31 December 2001, the Genesis algo- rithm categorized the flow to be 67 % IS, 26% CME, and 7% CH. Counter-streaming electrons signatures were identified for 23% of that total time interval. The Genesis onboard shock detector was set seventeen times, and nearly all were verified to be ac- tual CME-associated shocks. We will present the results of the autonomous algorithm obtained up to the time of the EGS meeting, as well as our assessment of the validity of those onboard results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008cosp...37.3238T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008cosp...37.3238T"><span id="translatedtitle">A model of the <span class="hlt">solar</span> <span class="hlt">wind</span> driven by supergranular circulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tu, Chuanyi; Tian, Hui; He, Jiansen; Marsch, Eckart</p> <p></p> <p>The scenario for the origin of the <span class="hlt">solar</span> <span class="hlt">wind</span> driven by the supergranular circulation as suggested by Tu et al. (2005) is tested with model calculation and data analysis. This scenario assumes that the fast <span class="hlt">solar</span> <span class="hlt">wind</span> originates at heights above 5 Mm in magnetically open funnels in corona holes. Mass and energy are supplied to the <span class="hlt">solar</span> <span class="hlt">wind</span> through reconnection of open field lines in the funnels with closed loops advected by the supergranular circulation to the reconnection sites. To test this scenario, we developed a one-dimensional one-fluid model with mass flux and energy flux supplied at 5 Mm to mimic the result expected from field-line reconnections. The upward flow and the downward flow resulting from this model are shown to be consistent with the blueshift of Ne VIII and redshift of Si II observed by SUMMER on SOHO. The mass and energy supply rates required by the model are shown to be consistent with the mass and energy delivery rates due to reconnection between magnetic loops in the intra-network region and open magnetic funnel at the network intersections. The model calculations support the scenario of the <span class="hlt">solar</span> <span class="hlt">wind</span> being driven by supergranular circulation. A discussion of a possible mechanism for the <span class="hlt">solar</span> <span class="hlt">wind</span> origin in the quiet sun is also given, where the <span class="hlt">solar</span> <span class="hlt">wind</span> is suggested to start flowing outward at a height of 20 Mm, which is higher than the emission height of Ne VIII ( 5 Mm). We found that Ne VIII blueshifts can occur at both legs of some closed loops, which suggests that mass can be supplied upward to the corona from both footpoints. Tu, C.-Y., Zhou, C., Marsch, E., Xia, L.-D., Zhao, L., Wang, J.-X., and Wilhelm, K., <span class="hlt">Solar</span> <span class="hlt">wind</span> origin in coronal funnels, Science, 308, 519, 2005.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22126793','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22126793"><span id="translatedtitle"><span class="hlt">SOLAR</span> <span class="hlt">WIND</span> HEAVY IONS OVER <span class="hlt">SOLAR</span> CYCLE 23: ACE/SWICS MEASUREMENTS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lepri, S. T.; Landi, E.; Zurbuchen, T. H.</p> <p>2013-05-01</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> plasma and compositional properties reflect the physical properties of the corona and its evolution over time. Studies comparing the previous <span class="hlt">solar</span> minimum with the most recent, unusual <span class="hlt">solar</span> minimum indicate that significant environmental changes are occurring globally on the Sun. For example, the magnetic field decreased 30% between the last two <span class="hlt">solar</span> minima, and the ionic charge states of O have been reported to change toward lower values in the fast <span class="hlt">wind</span>. In this work, we systematically and comprehensively analyze the compositional changes of the <span class="hlt">solar</span> <span class="hlt">wind</span> during cycle 23 from 2000 to 2010 while the Sun moved from <span class="hlt">solar</span> maximum to <span class="hlt">solar</span> minimum. We find a systematic change of C, O, Si, and Fe ionic charge states toward lower ionization distributions. We also discuss long-term changes in elemental abundances and show that there is a {approx}50% decrease of heavy ion abundances (He, C, O, Si, and Fe) relative to H as the Sun went from <span class="hlt">solar</span> maximum to <span class="hlt">solar</span> minimum. During this time, the relative abundances in the slow <span class="hlt">wind</span> remain organized by their first ionization potential. We discuss these results and their implications for models of the evolution of the <span class="hlt">solar</span> atmosphere, and for the identification of the fast and slow <span class="hlt">wind</span> themselves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2007_jgr_A01102.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2007_jgr_A01102.pdf"><span id="translatedtitle"><span class="hlt">Wind</span>/WAVES observations of high-frequency plasma waves in <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection exhausts</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>in these studies include low-frequency waves such as lower hybrid waves as well as high-frequency waves such as ion acoustic, upper hybrid, and Langmuir waves. In addition, isolated bipolar electric field pulses called<span class="hlt">Wind</span>/WAVES observations of high-frequency plasma waves in <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection exhausts K. E. J</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/jck_hellinger/jck_hellinger.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/jck_hellinger/jck_hellinger.pdf"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> proton temperature anisotropy: Linear theory and <span class="hlt">WIND</span>/SWE observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> proton temperature anisotropy: Linear theory and <span class="hlt">WIND</span>/SWE observations Petr Hellinger,1/SWE observations (Kasper et al., 2006) of bkp and T?p/Tkp (where bkp is the proton parallel beta and T?p and Tkp are the perpendicular and parallel proton temperatures, respectively; here parallel and perpendicular indicate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/jdr_riazantseva/jdr_riazantseva.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/jdr_riazantseva/jdr_riazantseva.pdf"><span id="translatedtitle">Sharp boundaries of small-and middle-scale <span class="hlt">solar</span> <span class="hlt">wind</span> structures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p>Sharp boundaries of small- and middle-scale <span class="hlt">solar</span> <span class="hlt">wind</span> structures M. O. Riazantseva1 and G. N-scale <span class="hlt">solar</span> <span class="hlt">wind</span> plasma structures. We present examples and statistical results from simultaneous plasma and magnetic field measurements by Interball-1 and <span class="hlt">Wind</span> from 1996 to 1999. The behavior of the <span class="hlt">solar</span> <span class="hlt">wind</span> bulk</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhDT........23Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhDT........23Z"><span id="translatedtitle">Simulation and optimum design of hybrid <span class="hlt">solar-wind</span> and <span class="hlt">solar-wind</span>-diesel power generation systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhou, Wei</p> <p></p> <p><span class="hlt">Solar</span> and <span class="hlt">wind</span> energy systems are considered as promising power generating sources due to its availability and topological advantages in local power generations. However, a drawback, common to <span class="hlt">solar</span> and <span class="hlt">wind</span> options, is their unpredictable nature and dependence on weather changes, both of these energy systems would have to be oversized to make them completely reliable. Fortunately, the problems caused by variable nature of these resources can be partially overcome by integrating these two resources in a proper combination to form a hybrid system. However, with the increased complexity in comparison with single energy systems, optimum design of hybrid system becomes more complicated. In order to efficiently and economically utilize the renewable energy resources, one optimal sizing method is necessary. This thesis developed an optimal sizing method to find the global optimum configuration of stand-alone hybrid (both <span class="hlt">solar-wind</span> and <span class="hlt">solar-wind</span>-diesel) power generation systems. By using Genetic Algorithm (GA), the optimal sizing method was developed to calculate the system optimum configuration which offers to guarantee the lowest investment with full use of the PV array, <span class="hlt">wind</span> turbine and battery bank. For the hybrid <span class="hlt">solar-wind</span> system, the optimal sizing method is developed based on the Loss of Power Supply Probability (LPSP) and the Annualized Cost of System (ACS) concepts. The optimization procedure aims to find the configuration that yields the best compromise between the two considered objectives: LPSP and ACS. The decision variables, which need to be optimized in the optimization process, are the PV module capacity, <span class="hlt">wind</span> turbine capacity, battery capacity, PV module slope angle and <span class="hlt">wind</span> turbine installation height. For the hybrid <span class="hlt">solar-wind</span>-diesel system, minimization of the system cost is achieved not only by selecting an appropriate system configuration, but also by finding a suitable control strategy (starting and stopping point) of the diesel generator. The optimal sizing method was developed to find the system optimum configuration and settings that can achieve the custom-required Renewable Energy Fraction (fRE) of the system with minimum Annualized Cost of System (ACS). Du to the need for optimum design of the hybrid systems, an analysis of local weather conditions (<span class="hlt">solar</span> radiation and <span class="hlt">wind</span> speed) was carried out for the potential installation site, and mathematical simulation of the hybrid systems' components was also carried out including PV array, <span class="hlt">wind</span> turbine and battery bank. By statistically analyzing the long-term hourly <span class="hlt">solar</span> and <span class="hlt">wind</span> speed data, Hong Kong area is found to have favorite <span class="hlt">solar</span> and <span class="hlt">wind</span> power resources compared with other areas, which validates the practical applications in Hong Kong and Guangdong area. Simulation of PV array performance includes three main parts: modeling of the maximum power output of the PV array, calculation of the total <span class="hlt">solar</span> radiation on any tilted surface with any orientations, and PV module temperature predictions. Five parameters are introduced to account for the complex dependence of PV array performance upon <span class="hlt">solar</span> radiation intensities and PV module temperatures. The developed simulation model was validated by using the field-measured data from one existing building-integrated photovoltaic system (BIPV) in Hong Kong, and good simulation performance of the model was achieved. Lead-acid batteries used in hybrid systems operate under very specific conditions, which often cause difficulties to predict when energy will be extracted from or supplied to the battery. In this thesis, the lead-acid battery performance is simulated by three different characteristics: battery state of charge (SOC), battery floating charge voltage and the expected battery lifetime. Good agreements were found between the predicted values and the field-measured data of a hybrid <span class="hlt">solar-wind</span> project. At last, one 19.8kW hybrid <span class="hlt">solar-wind</span> power generation project, designed by the optimal sizing method and set up to supply power for a telecommunication relay station on a remote island of Guangdong pr</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930049627&hterms=technologie&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dtechnologie','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930049627&hterms=technologie&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dtechnologie"><span id="translatedtitle">Ions with low charges in the <span class="hlt">solar</span> <span class="hlt">wind</span> as measured by SWICS on board Ulysses. [<span class="hlt">Solar</span> <span class="hlt">Wind</span> Ion Composition Spectrometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Geiss, J.; Ogilvie, K. W.; Von Steiger, R.; Mall, U.; Gloeckler, G.; Galvin, A. B.; Ipavich, F.; Wilken, B.; Gliem, F.</p> <p>1992-01-01</p> <p>We present new data on rare ions in the <span class="hlt">solar</span> <span class="hlt">wind</span>. Using the Ulysses-SWICS instrument with its very low background we have searched for low-charge ions during a 6-d period of low-speed <span class="hlt">solar</span> <span class="hlt">wind</span> and established sensitive upper limits for many species. In the <span class="hlt">solar</span> <span class="hlt">wind</span>, we found He(1+)/He(2+) of less than 5 x 10 exp -4. This result and the charge state distributions of heavier elements indicate that all components of the investigated ion population went through a regular coronal expansion and experienced the typical electron temperatures of 1 to 2 million Kelvin. We argue that the virtual absence of low-charge ions demonstrates a very low level of nonsolar contamination in the source region of the <span class="hlt">solar</span> <span class="hlt">wind</span> sample we studied. Since this sample showed the FlP effect typical for low-speed <span class="hlt">solar</span> <span class="hlt">wind</span>, i.e., an enhancement in the abundances of elements with low first ionization potential, we conclude that this enhancement was caused by an ion-atom separation mechanism operating near the <span class="hlt">solar</span> surface and not by foreign material in the corona.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7577B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7577B"><span id="translatedtitle">Rosetta observations of <span class="hlt">solar</span> <span class="hlt">wind</span> deflection in the coma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Broiles, Thomas; Burch, James; Clark, George; Goldstein, Raymond; Koenders, Christoph; Mandt, Kathleen; Mokashi, Prachet; Samara, Marilia</p> <p>2015-04-01</p> <p>Until recently, study of the <span class="hlt">solar</span> <span class="hlt">wind</span> around comets was limited to remote observations and brief in-situ encounters. With the arrival of Rosetta at the comet Churyumov-Gerasimenko (CG), we have had near constant <span class="hlt">solar</span> <span class="hlt">wind</span> observations at the comet for over 6 months. This is an unprecedented opportunity to study this dynamic interaction over time. Neutral atoms produced by the comet become ionized through photoionization or charge-exchange with the <span class="hlt">solar</span> <span class="hlt">wind</span>. The freshly ionized particles experience v x B electric field and begin to gyrate around the interplanetary magnetic field. Currently, CG is ~2.6 AU from the Sun, and as of this writing, neutral production is still relatively low. Consequently, most pickup ions are produced locally (< few hundred kilometers), and a diamagnetic cavity may not exist. Moreover, neutral production is variable and changes over the comet's rotational period. We find the following: 1) The <span class="hlt">solar</span> <span class="hlt">wind</span> is heavily deflected near the comet (in some cases >45° away from the anti-sunward direction). 2) The <span class="hlt">solar</span> <span class="hlt">wind</span> helium experiences less deflection than the protons. 3) The periodicity of the deflection is highly variable, and can vary over minutes or hours. From these results, we conclude that the <span class="hlt">solar</span> <span class="hlt">wind</span> is deflected by a mechanism very close to the comet. We suggest the following possibilities: 1) The <span class="hlt">solar</span> <span class="hlt">wind</span> could be deflected by a Lorenz force in the opposite direction to that experienced by the pickup ions, which would also conserve the momentum of the two fluid system. This would explain why <span class="hlt">solar</span> <span class="hlt">wind</span> protons are more strongly deflected than the heavier alpha particles. Additionally, this would explain the periodicity of the deflections, which would react to changes in the interplanetary magnetic field. 2) The <span class="hlt">solar</span> <span class="hlt">wind</span> deflection might occur from strong charging of comet's nucleus. In which case, the nucleus may charge both positively or negatively. The nucleus could charge positively due photoionization of the surface, but could also charge negatively due to the high electron fluxes that are regularly observed. This mechanism might also explain the preferential deflection of lighter ions and the variable periodicity of the deflection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1215020','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1215020"><span id="translatedtitle">Role of Concentrating <span class="hlt">Solar</span> Power in Integrating <span class="hlt">Solar</span> and <span class="hlt">Wind</span> Energy: Preprint</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Denholm, P.; Mehos, M.</p> <p>2015-06-03</p> <p>As <span class="hlt">wind</span> and <span class="hlt">solar</span> photovoltaics (PV) increase in penetration it is increasingly important to examine enabling technologies that can help integrate these resources at large scale. Concentrating <span class="hlt">solar</span> power (CSP) when deployed with thermal energy storage (TES) can provide multiple services that can help integrate variable generation (VG) resources such as <span class="hlt">wind</span> and PV. CSP with TES can provide firm, highly flexible capacity, reducing minimum generation constraints which limit penetration and results in curtailment. By acting as an enabling technology, CSP can complement PV and <span class="hlt">wind</span>, substantially increasing their penetration in locations with adequate <span class="hlt">solar</span> resource.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/jdr_sw9/jdr_sw9.withthumbs.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/jdr_sw9/jdr_sw9.withthumbs.pdf"><span id="translatedtitle">The <span class="hlt">solar</span> <span class="hlt">wind</span> in the outer heliosphere John D. Richardson, Karolen I Paularena, and Chi Wang</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p>The <span class="hlt">solar</span> <span class="hlt">wind</span> in the outer heliosphere John D. Richardson, Karolen I Paularena, and Chi Wang. This paper reviews <span class="hlt">solar</span> <span class="hlt">wind</span> observations in the outer heliosphere, concentrating on new developments in 1996, speed oscillations with periods of 1-3 days which comprise 10% of the <span class="hlt">solar</span> <span class="hlt">wind</span> data. <span class="hlt">Solar</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.prl.res.in/~jerry/PAPERS/jgr_2005_reprint.pdf','EPRINT'); return false;" href="http://www.prl.res.in/~jerry/PAPERS/jgr_2005_reprint.pdf"><span id="translatedtitle">Resolving the enigmatic <span class="hlt">solar</span> <span class="hlt">wind</span> disappearance event of 11 May 1999</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Padmanabhan, Janardhan</p> <p></p> <p>Resolving the enigmatic <span class="hlt">solar</span> <span class="hlt">wind</span> disappearance event of 11 May 1999 P. Janardhan Astronomy by an unusually low-density (<span class="hlt">solar</span> <span class="hlt">wind</span> for a period of over 1 day or the <span class="hlt">solar</span> source of this event. Using <span class="hlt">solar</span> <span class="hlt">wind</span> velocity measurements from the four-station IPS observatory</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.people.virginia.edu/~rej/papers2013/Funsten-etal-2013.pdf','EPRINT'); return false;" href="http://www.people.virginia.edu/~rej/papers2013/Funsten-etal-2013.pdf"><span id="translatedtitle">Reflection of <span class="hlt">solar</span> <span class="hlt">wind</span> hydrogen from the lunar surface H. O. Funsten,1</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Johnson, Robert E.</p> <p></p> <p>Reflection of <span class="hlt">solar</span> <span class="hlt">wind</span> hydrogen from the lunar surface H. O. Funsten,1 F. Allegrini,2,3 P. A] The <span class="hlt">solar</span> <span class="hlt">wind</span> continuously flows out from the Sun and directly interacts with the surfaces of dust and airless planetary bodies throughout the <span class="hlt">solar</span> system. A significant fraction of <span class="hlt">solar</span> <span class="hlt">wind</span> ions reflect</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/jdr_maria_adv/jdr_maria_adv.withthumbs.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/jdr_maria_adv/jdr_maria_adv.withthumbs.pdf"><span id="translatedtitle">The characteristics of sharp (small-scale) boundaries of <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and magnetic field structures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p>The characteristics of sharp (small-scale) boundaries of <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and magnetic field investigate properties of large (>20%) and sharp (<span class="hlt">solar</span> <span class="hlt">wind</span> ion flux changes using INTERBALL-1 are the boundaries of small-scale and mid- dle-scale <span class="hlt">solar</span> <span class="hlt">wind</span> structures. We describe the behavior of the <span class="hlt">solar</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://ftp.lpi.usra.edu/pub/outgoing/lpsc2009/full456.pdf','EPRINT'); return false;" href="ftp://ftp.lpi.usra.edu/pub/outgoing/lpsc2009/full456.pdf"><span id="translatedtitle">Wednesday, March 25, 2009 <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> AND GENESIS: MEASUREMENTS AND INTERPRETATION</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Rathbun, Julie A.</p> <p></p> <p>Wednesday, March 25, 2009 <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> AND GENESIS: MEASUREMENTS AND INTERPRETATION 1:30 p. Wieler R. Preliminary Genesis Bulk <span class="hlt">Solar</span> <span class="hlt">Wind</span> Ar, Kr, and Xe Abundances in Comparison to Young Lunar Regolith and <span class="hlt">Solar</span> Photosphere Data [#1964] We present preliminary Genesis bulk <span class="hlt">solar</span> <span class="hlt">wind</span> Ar, Kr, and Xe</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19950057086&hterms=diurnal+variation+radar&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddiurnal%2Bvariation%2Bradar','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19950057086&hterms=diurnal+variation+radar&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddiurnal%2Bvariation%2Bradar"><span id="translatedtitle"><span class="hlt">Solar</span> activity variations in midlatitude thermospheric meridional <span class="hlt">winds</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hedin, A. E.; Buonsanto, M. J.; Codrescu, M.; Duboin, M.-L.; Fesen, C. G.; Hagan, M. E.; Miller, K. L.; Sipler, D. P.</p> <p>1994-01-01</p> <p>Upper thermospheric meridional <span class="hlt">wind</span> data at midlatitudes and for low magnetic activity are examined for <span class="hlt">solar</span> activity variations following an analysis scheme suggested by a Coordinated Analysis of the Thermosphere workshop. <span class="hlt">Wind</span> data from incoherent scatter, Fabry-Perot, and F2 peak heights show decreasing diurnal amplitudes with increasing <span class="hlt">solar</span> activity during all seasons, except for Saint Santin data, which show a slight increase in summer. Equivalent <span class="hlt">winds</span> from F2 peak height data have strong decreases in diurnal amplitude in all seasons. The coupled thermosphere ionosphere model and thermosphere ionosphere global circulation model predictions of diurnal amplitude, while differing considerably in magnitude, also show decreasing amplitudes during all seasons except summer, while the HWM90 empirical model amplitudes increase slightly with <span class="hlt">solar</span> activity during all seasons. The diurnal mean <span class="hlt">wind</span> trends with <span class="hlt">solar</span> activity are fairly weak, except for Millstone Hill incoherent scatter radar, which shows a shift from strong southward to near zero or northward <span class="hlt">wind</span> with increasing activity. Model results for the mean generally fall within the band of measurements. Near midnight, most of the data also show that the typically southward <span class="hlt">winds</span> weaken with increasing solart activity in all seasons except summer, when results are mixed. There are significant differences between the trends and between absolute values for the various data sets and models which need further investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19990056503&hterms=Ulysses&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DUlysses','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19990056503&hterms=Ulysses&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DUlysses"><span id="translatedtitle">Charge state composition in coronal hole and CME related <span class="hlt">solar</span> <span class="hlt">wind</span>: Latitudinal variations observed by Ulysses and <span class="hlt">WIND</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Galvin, A. B.; Gloeckler, G.</p> <p>1997-01-01</p> <p>Iron charge states in recurrent coronal hole-associated <span class="hlt">solar</span> <span class="hlt">wind</span> flows are obtained in the ecliptic by <span class="hlt">WIND</span>/SMS, while measurements of iron and silicon from the polar coronal holes are available from Ulysses/SWICS. Ulysses/SWICS also provides ion composition of coronal mass ejection (CME)-related <span class="hlt">solar</span> <span class="hlt">wind</span>. Both coronal hole-associated and CME-related <span class="hlt">solar</span> <span class="hlt">wind</span> charge charges show heliographic latitudinal variations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21567559','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21567559"><span id="translatedtitle"><span class="hlt">SOLAR</span> <span class="hlt">WIND</span> MODELING WITH TURBULENCE TRANSPORT AND HEATING</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Usmanov, Arcadi V.; Goldstein, Melvyn L.; Matthaeus, William H.; Breech, Benjamin A.</p> <p>2011-02-01</p> <p>We have developed an axisymmetric steady-state <span class="hlt">solar</span> <span class="hlt">wind</span> model that describes properties of the large-scale <span class="hlt">solar</span> <span class="hlt">wind</span>, interplanetary magnetic field, and turbulence throughout the heliosphere from 0.3 AU to 100 AU. The model is based on numerical solutions of large-scale Reynolds-averaged magnetohydrodynamic equations coupled with a set of small-scale transport equations for the turbulence energy, normalized cross helicity, and correlation scale. The combined set of time-dependent equations is solved in the frame of reference corotating with the Sun using a time-relaxation method. We use the model to study the self-consistent interaction between the large-scale <span class="hlt">solar</span> <span class="hlt">wind</span> and smaller-scale turbulence and the role of the turbulence in the large-scale structure and temperature distribution in the <span class="hlt">solar</span> <span class="hlt">wind</span>. To illuminate the roles of the turbulent cascade and the pickup protons in heating the <span class="hlt">solar</span> <span class="hlt">wind</span> depending on the heliocentric distance, we compare the model results with and without turbulence/pickup protons. The variations of plasma temperature in the outer heliosphere are compared with Ulysses and Voyager 2 observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4308709','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4308709"><span id="translatedtitle">Direct evidence for kinetic effects associated with <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xu, Xiaojun; Wang, Yi; Wei, Fengsi; Feng, Xueshang; Deng, Xiaohua; Ma, Yonghui; Zhou, Meng; Pang, Ye; Wong, Hon-Cheng</p> <p>2015-01-01</p> <p>Kinetic effects resulting from the two-fluid physics play a crucial role in the fast collisionless reconnection, which is a process to explosively release massive energy stored in magnetic fields in space and astrophysical plasmas. In-situ observations in the Earth's magnetosphere provide solid consistence with theoretical models on the point that kinetic effects are required in the collisionless reconnection. However, all the observations associated with <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection have been analyzed in the context of magnetohydrodynamics (MHD) although a lot of <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection exhausts have been reported. Because of the absence of kinetic effects and substantial heating, whether the reconnections are still ongoing when they are detected in the <span class="hlt">solar</span> <span class="hlt">wind</span> remains unknown. Here, by dual-spacecraft observations, we report a <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection with clear Hall magnetic fields. Its corresponding Alfvenic electron outflow jet, derived from the decouple between ions and electrons, is identified, showing direct evidence for kinetic effects that dominate the collisionless reconnection. The turbulence associated with the exhaust is a kind of background <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence, implying that the reconnection generated turbulence has not much developed. PMID:25628139</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/nlin/0611034v1','EPRINT'); return false;" href="http://arxiv.org/pdf/nlin/0611034v1"><span id="translatedtitle">Magnetic field gradients in <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and geophysics periods</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>A. Bershadskii</p> <p>2006-11-16</p> <p>Using recent data obtained by Advanced Composition Explorer (ACE) the pumping scale of the magnetic field gradients of the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma has been calculated. This pumping scale is found to be equal to 24h $\\pm$ 2h. The ACE spacecraft orbits at the L1 libration point which is a point of Earth-Sun gravitational equilibrium about 1.5 million km from Earth. Since the Earth's magnetosphere extends into the vacuum of space from approximately 80 to 60,000 kilometers on the side toward the Sun the pumping scale cannot be a consequence of the 24h-period of the Earth's rotation. Vise versa, a speculation is suggested that for the very long time of the coexistence of Earth and of the <span class="hlt">solar</span> <span class="hlt">wind</span> the weak interaction between the <span class="hlt">solar</span> <span class="hlt">wind</span> and Earth could lead to stochastic synchronization between the Earth's rotation and the pumping scale of the <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field gradients. This synchronization could transform an original period of the Earth's rotation to the period close to the pumping scale of the <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field gradients.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22133859','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22133859"><span id="translatedtitle">COLLISIONLESS DAMPING AT ELECTRON SCALES IN <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> TURBULENCE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>TenBarge, J. M.; Howes, G. G.; Dorland, W.</p> <p>2013-09-10</p> <p>The dissipation of turbulence in the weakly collisional <span class="hlt">solar</span> <span class="hlt">wind</span> plasma is governed by unknown kinetic mechanisms. Two candidates have been suggested to play an important role in the dissipation, collisionless damping via wave-particle interactions and dissipation in small-scale current sheets. High resolution spacecraft measurements of the turbulent magnetic energy spectrum provide important constraints on the dissipation mechanism. The limitations of popular fluid and hybrid numerical schemes for simulation of the dissipation of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence are discussed, and instead a three-dimensional kinetic approach is recommended. We present a three-dimensional nonlinear gyrokinetic simulation of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence at electron scales that quantitatively reproduces the exponential form of the turbulent magnetic energy spectrum measured in the <span class="hlt">solar</span> <span class="hlt">wind</span>. A weakened cascade model that accounts for nonlocal interactions and collisionless Landau damping also quantitatively agrees with the observed exponential form. These results establish that a turbulent cascade of kinetic Alfven waves that is terminated by collisionless Landau damping is sufficient to explain the observed magnetic energy spectrum in the dissipation range of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25628139','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25628139"><span id="translatedtitle">Direct evidence for kinetic effects associated with <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xu, Xiaojun; Wang, Yi; Wei, Fengsi; Feng, Xueshang; Deng, Xiaohua; Ma, Yonghui; Zhou, Meng; Pang, Ye; Wong, Hon-Cheng</p> <p>2015-01-01</p> <p>Kinetic effects resulting from the two-fluid physics play a crucial role in the fast collisionless reconnection, which is a process to explosively release massive energy stored in magnetic fields in space and astrophysical plasmas. In-situ observations in the Earth's magnetosphere provide solid consistence with theoretical models on the point that kinetic effects are required in the collisionless reconnection. However, all the observations associated with <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection have been analyzed in the context of magnetohydrodynamics (MHD) although a lot of <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection exhausts have been reported. Because of the absence of kinetic effects and substantial heating, whether the reconnections are still ongoing when they are detected in the <span class="hlt">solar</span> <span class="hlt">wind</span> remains unknown. Here, by dual-spacecraft observations, we report a <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection with clear Hall magnetic fields. Its corresponding Alfvenic electron outflow jet, derived from the decouple between ions and electrons, is identified, showing direct evidence for kinetic effects that dominate the collisionless reconnection. The turbulence associated with the exhaust is a kind of background <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence, implying that the reconnection generated turbulence has not much developed. PMID:25628139</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19720036359&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19720036359&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon"><span id="translatedtitle">Interaction of the <span class="hlt">solar</span> <span class="hlt">wind</span> with the moon.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ness, N. F.</p> <p>1972-01-01</p> <p>During its orbit about the earth, the moon is located in the interplanetary medium or in the geomagnetosheath-geomagnetotail formed by the <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with earth. In the tail, no evidence is found for a lunar magnetic field. In the interplanetary medium, no evidence exists for a bow shock or a trailing shock, although a well defined plasma wake region is observed in the anti-<span class="hlt">solar</span> <span class="hlt">wind</span> direction. The moon absorbs the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma that strikes its surface and creates a void region or cavity in the flow. The observed lunar Mach cone gives evidence for the anisotropic propagation of waves in the magnetized collisionless warm plasma of the <span class="hlt">solar</span> <span class="hlt">wind</span>. The transmission of microstructural discontinuities in the interplanetary medium past the moon shows little distortion, indicating a low effective electrical conductivity of the lunar body. Fluctuations of the interplanetary magnetic field upstream from the plasma wake are stimulated by the disturbed conditions in that region. The moon behaves like a cold, nonmagnetic, fully absorbing dielectric sphere in the <span class="hlt">solar</span> <span class="hlt">wind</span> flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19950056914&hterms=solar+term&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bterm','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19950056914&hterms=solar+term&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bterm"><span id="translatedtitle">Long term periodicity in <span class="hlt">solar</span> <span class="hlt">wind</span> velocity during the last three <span class="hlt">solar</span> cycles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gazis, P. R.; Richardson, J. D.; Paularena, K. I.</p> <p>1995-01-01</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> measurements from the Pioneer 10, Pioneer 11, Voyager 2, IMP 8, and Pioneer Venus Orbiter (PVO) spacecraft were examined to search for long-term periodicities during the last three <span class="hlt">solar</span> cycles. For the time of the last <span class="hlt">solar</span> maximum, these measurements confirm the existence of the periodic 1.3-year enhancements in <span class="hlt">solar</span> <span class="hlt">wind</span> velocity reported by Richardson et al. (1994). For most of the preceding two <span class="hlt">solar</span> cycles, long-term velocity enhancements occurred that were similar in structure but lacked the 1.3-year periodicity. It appears that long-term enhancements in <span class="hlt">solar</span> <span class="hlt">wind</span> velocity, with durations on the order of a few months to a year, are a common feature throughout the heliosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.6705K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.6705K"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> Drivers of Storm-Time Radiation Belt Variations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kilpua, Emilia; Hietala, Heli; Turner, Drew; Koskinen, Hannu; Pulkkinen, Tuija; Rodriguez, Juan; Reeves, Geoffrey; Claudepierre, Seth; Spence, Harlan</p> <p>2015-04-01</p> <p>It is an outstanding question why some storms result in an increase of the outer radiation belt electron fluxes, while others deplete them or produce no change. One approach to this problem is to look at differences in the large-scale <span class="hlt">solar</span> <span class="hlt">wind</span> storm drivers. The drivers have traditionally been classified to Stream Interaction Regions (SIRs) and Interplanetary Coronal Mass Ejections (ICMEs). However, ICMEs and SIRs are complex structures: SIRs consist of a slow stream followed by a turbulent, higher pressure interface region and then a faster stream. The core of the ICME is an ejecta. If the mass ejection is fast enough, it can drive a shock in front of it. This leads to the formation of a sheath region between the interplanetary shock and the leading edge of the ejecta. Fast streams that are integral part of SIR may or may not follow the ICME. The <span class="hlt">solar</span> <span class="hlt">wind</span> properties, and hence, the magnetospheric driving of different substructures in SIRs and ICMEs are very distinct. In this work we will investigate the radiation belt response to different storm drivers by combining near-Earth <span class="hlt">solar</span> <span class="hlt">wind</span> observations, long-term geosynchronous observations from GOES spanning over 1.5 <span class="hlt">solar</span> cycles (1995-2013) and the state-of-the art Van Allen Probe data. Our study uses superposed epoch analysis with multiple reference times and we expand/contract each <span class="hlt">solar</span> <span class="hlt">wind</span> substructure to the population mean. This novel approach allows us to determine the typical evolution of the electron fluxes during each <span class="hlt">solar</span> <span class="hlt">wind</span> structure. Our results show that the separation of the effects from different parts of the ICME and SIRs will be crucial for understanding how radiation belt electrons react to different <span class="hlt">solar</span> <span class="hlt">wind</span> driving conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUSMSM43D..01R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUSMSM43D..01R"><span id="translatedtitle">The <span class="hlt">Solar</span> Cycle Dependence of the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Sources of Geomagnetic Activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Richardson, I.</p> <p>2005-05-01</p> <p>Variations of average geomagnetic activity levels occur during the <span class="hlt">solar</span> cycle, as measured by long term (much greater than a <span class="hlt">solar</span> rotation) averages of geomagnetic indices such as aa. These variations are generally not dominated by energetic <span class="hlt">solar</span> events (which may be intense but brief) but by changes in the background <span class="hlt">solar</span> <span class="hlt">wind</span>, including the effects of changes in the <span class="hlt">solar</span> open magnetic flux and <span class="hlt">solar</span> <span class="hlt">wind</span> speed. They also do not closely follow the <span class="hlt">solar</span> activity cycle. In particular, activity tends to be enhanced during the declining phase of the cycle due to the presence of corotating <span class="hlt">solar</span> <span class="hlt">wind</span> streams. In addition, the period right at <span class="hlt">solar</span> (sunspot) maximum is often marked by a decrease in activity levels, apparently associated with the weaker interplanetary magnetic fields around the time of <span class="hlt">solar</span> field reversal, a temporary lull in the occurrence of energetic <span class="hlt">solar</span> events, and the general absence of fast <span class="hlt">solar</span> <span class="hlt">wind</span>. Considering the sources of geomagnetic storms, the most intense storms as almost invariably associated with the passage of interplanetary coronal mass ejections, the associated shocks and compressed post-shock plasma. The presence of a strong southward magnetic field is an important parameter determining the storm size; speed shows a much weaker dependence. Such events predominantly occur at higher activity levels, and typically show two occurrence rate peaks, before and after a temporary decline right at <span class="hlt">solar</span> maximum. Weaker storms are produced by both ICMEs and corotating streams at high activity levels, and predominantly by corotating streams at lower activity levels. We illustrate these points using observations from 1972 to present from an analysis of <span class="hlt">solar</span> <span class="hlt">wind</span> structures inferred from in-situ data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AAS...22440801D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AAS...22440801D"><span id="translatedtitle">Observing MHD Waves in the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Acceleration Region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DeForest, Craig; McComas, Dave; Howard, Tim A.</p> <p>2014-06-01</p> <p>We have, for the first time, observed and characterized compressive waves propagating both outward and inward in the outer <span class="hlt">solar</span> corona above 4 Rs. In addition to detecting the waves, we have used them to measure outflow in the all-important <span class="hlt">wind</span> acceleration region. Because the corona is an MHD system, any disturbance in the corona launches low-frequency waves that propagate at the familiar MHD speeds and serve to communicate that disturbance to other parts of the system. Through careful filtration of synoptic STEREO-A/COR-2 data, we have been able to measure both inbound and outbound waves at all locations in the <span class="hlt">solar</span> corona. By measuring in/out asymmetries in the wave characteristics we have been able to estimate the <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration profile. Further, we are able to estimate the location of the Alfvén surface - the hard-to-measure transition between the corona and the superalfvénic <span class="hlt">solar</span> <span class="hlt">wind</span>, and the boundary at which <span class="hlt">solar</span> magnetic field lines transition from "closed" to "open". There is a great deal of work to be done beyond these preliminary results, which - it is hoped - open a new avenue for understanding coronal dynamics and the origin of the <span class="hlt">solar</span> <span class="hlt">wind</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015P%26SS..115..110K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015P%26SS..115..110K"><span id="translatedtitle">Simulation of <span class="hlt">solar</span> <span class="hlt">wind</span> space weathering in orthopyroxene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuhlman, Kimberly R.; Sridharan, Kumar; Kvit, Alexander</p> <p>2015-09-01</p> <p>We have simulated <span class="hlt">solar</span> <span class="hlt">wind</span>-based space weathering on airless bodies in our <span class="hlt">Solar</span> System by implanting hydrogen and helium into orthopyroxene at <span class="hlt">solar</span> <span class="hlt">wind</span> energies (~1 keV/amu). Here we present the results of the first scanning transmission electron microscope (STEM) study of one of these simulants. It has been demonstrated that the visible/near infrared (VNIR) reflectance spectra of airless bodies are dependent on the size and abundance of nanophase iron (npFe0) particles in the outer rims of regolith grains. However, the mechanism of formation of npFe0 in the patina on lunar regolith grains and in lunar agglutinates remains debated. As the lattice is disrupted by hydrogen and helium implantation, broken bonds are created. These dangling bonds are free to react with hydrogen, creating OH and/or H2O molecules within the grain. These molecules may diffuse out through the damaged lattice and migrate toward the cold traps identified at the lunar poles. This mechanism would leave the iron in a reduced state and able to form npFe0. This work illustrates that npFe0 can be nucleated in orthopyroxene under implantation of <span class="hlt">solar</span> <span class="hlt">wind</span> hydrogen and helium. Our data suggest that the <span class="hlt">solar</span> <span class="hlt">wind</span> provides a mechanism by which iron is reduced in the grain and npFe0 is nucleated in the outer surfaces of regolith grains. This formation mechanism should also operate on other airless bodies in the <span class="hlt">Solar</span> System.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMSH11B1620K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMSH11B1620K"><span id="translatedtitle">The <span class="hlt">Solar</span> <span class="hlt">Wind</span> Electrons Alphas and Protons (SWEAP) Investigation for <span class="hlt">Solar</span> Probe Plus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kasper, J. C.; SWEAP Investigation Team</p> <p>2010-12-01</p> <p>The NASA <span class="hlt">Solar</span> Probe Plus mission will be humanity’s first direct visit to the atmosphere of our Sun. The spacecraft will close to within nine <span class="hlt">solar</span> radii (about four million miles) of the <span class="hlt">solar</span> surface in order to observe the heating of the corona and the acceleration of the <span class="hlt">solar</span> <span class="hlt">wind</span> first hand. A key requirement for <span class="hlt">Solar</span> Probe Plus is the ability to make continuous, accurate, and fast measurements of the electrons and ionized helium (alpha-particles) and hydrogen (protons) that constitute the bulk of the <span class="hlt">solar</span> <span class="hlt">wind</span>. The <span class="hlt">Solar</span> <span class="hlt">Wind</span> Electrons Alphas and Protons (SWEAP) Investigation is a two-instrument suite that provides these observations. The purpose of this talk is to describe the science motivation for SWEAP, the instrument designs, and the expected data products. SWEAP consists of the <span class="hlt">Solar</span> Probe Cup (SPC) and the <span class="hlt">Solar</span> Probe Analyzers (SPAN). SWEAP measurements enable discovery and understanding of <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration and formation, coronal and <span class="hlt">solar</span> <span class="hlt">wind</span> heating, high-energy particle acceleration, and the interaction between <span class="hlt">solar</span> <span class="hlt">wind</span> and the dust environment of the inner heliosphere. SPC is a Faraday Cup (FC) that looks at the Sun and measures ion and electron fluxes and flow angles as a function of energy. SPAN consists of an ion and electron electrostatic analyzer (ESA) on the ram side of SPP (SPAN-A) and an electron ESA on the anti-ram side (SPAN-B). SPAN-A and -B are rotated 90 degrees relative to one another so their broad FOV combine like the seams on a baseball to view the entire sky except for the region obscured by the heat shield. SWEAP data products include ion and electron velocity distribution functions with high energy and angular resolution at 0.5-16 Hz and flow angles and fluxes at 128 Hz. Continuous buffering provides triggered burst observations during shocks, reconnection events, and other transient structures with no changes to the instrument operating mode.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22348569','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22348569"><span id="translatedtitle">Weakest <span class="hlt">solar</span> <span class="hlt">wind</span> of the space age and the current 'MINI' <span class="hlt">solar</span> maximum</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>McComas, D. J.; Angold, N.; Elliott, H. A.; Livadiotis, G.; Schwadron, N. A.; Smith, C. W.; Skoug, R. M.</p> <p>2013-12-10</p> <p>The last <span class="hlt">solar</span> minimum, which extended into 2009, was especially deep and prolonged. Since then, sunspot activity has gone through a very small peak while the heliospheric current sheet achieved large tilt angles similar to prior <span class="hlt">solar</span> maxima. The <span class="hlt">solar</span> <span class="hlt">wind</span> fluid properties and interplanetary magnetic field (IMF) have declined through the prolonged <span class="hlt">solar</span> minimum and continued to be low through the current mini <span class="hlt">solar</span> maximum. Compared to values typically observed from the mid-1970s through the mid-1990s, the following proton parameters are lower on average from 2009 through day 79 of 2013: <span class="hlt">solar</span> <span class="hlt">wind</span> speed and beta (?11%), temperature (?40%), thermal pressure (?55%), mass flux (?34%), momentum flux or dynamic pressure (?41%), energy flux (?48%), IMF magnitude (?31%), and radial component of the IMF (?38%). These results have important implications for the <span class="hlt">solar</span> <span class="hlt">wind</span>'s interaction with planetary magnetospheres and the heliosphere's interaction with the local interstellar medium, with the proton dynamic pressure remaining near the lowest values observed in the space age: ?1.4 nPa, compared to ?2.4 nPa typically observed from the mid-1970s through the mid-1990s. The combination of lower magnetic flux emergence from the Sun (carried out in the <span class="hlt">solar</span> <span class="hlt">wind</span> as the IMF) and associated low power in the <span class="hlt">solar</span> <span class="hlt">wind</span> points to the causal relationship between them. Our results indicate that the low <span class="hlt">solar</span> <span class="hlt">wind</span> output is driven by an internal trend in the Sun that is longer than the ?11 yr <span class="hlt">solar</span> cycle, and they suggest that this current weak <span class="hlt">solar</span> maximum is driven by the same trend.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/574652','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/574652"><span id="translatedtitle">He abundance variations in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Observations from Ulysses</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Barraclough, B.L.; Feldman, W.C.; Gosling, J.T.; McComas, D.J.; Phillips, J.L.; Goldstein, B.E.</p> <p>1996-07-01</p> <p>The Ulysses mission is providing the first opportunity to observe variations in <span class="hlt">solar</span> <span class="hlt">wind</span> plasma parameters at heliographic latitudes far removed from the ecliptic plane. We present here an overview of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed and the variability in helium abundance, [He], for the entire mission to date, data on [He] in six high-latitude coronal mass ejections (CMEs), and a superposed epoch analysis of [He] variations at the seven heliospheric current sheet (HCS) crossings made during the rapid-latitude-scan portion of the mission. The differences in the variability of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed and [He] in high-latitude and equatorial regions are quite striking. <span class="hlt">Solar</span> <span class="hlt">wind</span> speed is generally low but highly variable near the <span class="hlt">solar</span> equator, while at higher latitudes the average speed is quite high (average speed around 760 km/s) with little variability. [He] can vary over nearly two decades at low <span class="hlt">solar</span> latitudes, while at high latitudes it varies only slightly around an average value of {approximately}4.3{percent}. In contrast to the high [He] that is often associated with CMEs observed near the ecliptic, none of the six high-speed CMEs encountered at high southern heliographic latitudes showed any significant variation in helium content from average values. Reasons for this difference between high and low latitude CME observations are not yet understood. A superposed epoch analysis of the [He] during all seven HCS crossings made as Ulysses passed from the southern to northern <span class="hlt">solar</span> hemisphere shows the expected [He] minimum near the crossing and a broad ({plus_minus}3day) period of low [He] around the crossing time. We briefly discuss how our <span class="hlt">solar</span> <span class="hlt">wind</span> [He] observations may provide an accurate measure of the helium composition for all regions of the sun lying above the helium ionization zone. {copyright} {ital 1996 American Institute of Physics.}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/20366193','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/20366193"><span id="translatedtitle">Generalized similarity in finite range <span class="hlt">solar</span> <span class="hlt">wind</span> magnetohydrodynamic turbulence.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chapman, S C; Nicol, R M</p> <p>2009-12-11</p> <p>Extended or generalized similarity is a ubiquitous but not well understood feature of turbulence that is realized over a finite range of scales. The ULYSSES spacecraft <span class="hlt">solar</span> polar passes at <span class="hlt">solar</span> minimum provide in situ observations of evolving anisotropic magnetohydrodynamic turbulence in the <span class="hlt">solar</span> <span class="hlt">wind</span> under ideal conditions of fast quiet flow. We find a single generalized scaling function characterizes this finite range turbulence and is insensitive to plasma conditions. The recent unusually inactive <span class="hlt">solar</span> minimum--with turbulent fluctuations down by a factor of approximately 2 in power--provides a test of this invariance. PMID:20366193</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21370889','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21370889"><span id="translatedtitle">Generalized Similarity in Finite Range <span class="hlt">Solar</span> <span class="hlt">Wind</span> Magnetohydrodynamic Turbulence</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chapman, S. C.; Nicol, R. M.</p> <p>2009-12-11</p> <p>Extended or generalized similarity is a ubiquitous but not well understood feature of turbulence that is realized over a finite range of scales. The ULYSSES spacecraft <span class="hlt">solar</span> polar passes at <span class="hlt">solar</span> minimum provide in situ observations of evolving anisotropic magnetohydrodynamic turbulence in the <span class="hlt">solar</span> <span class="hlt">wind</span> under ideal conditions of fast quiet flow. We find a single generalized scaling function characterizes this finite range turbulence and is insensitive to plasma conditions. The recent unusually inactive <span class="hlt">solar</span> minimum - with turbulent fluctuations down by a factor of approx2 in power - provides a test of this invariance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040082015','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040082015"><span id="translatedtitle">XMM-Newton Observations of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Charge Exchange Emission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Snowden, S. L.; Collier, M. R.; Kuntz, K. D.</p> <p>2004-01-01</p> <p>We present an XMM-Newton spectrum of diffuse X-ray emission from within the <span class="hlt">solar</span> system. The spectrum is dominated by O VII and O VIII lines at 0.57 keV and 0.65 keV, O VIII (and possibly Fe XVII) lines at approximately 0.8 keV, Ne IX lines at approximately 0.92 keV, and Mg XI lines at approximately 1.35 keV. This spectrum is consistent with what is expected from charge exchange emission between the highly ionized <span class="hlt">solar</span> <span class="hlt">wind</span> and either interstellar neutrals in the heliosphere or material from Earth's exosphere. The emission is clearly seen as a low-energy ( E less than 1.5 keV) spectral enhancement in one of a series of observations of the Hubble Deep Field North. The X-ray enhancement is concurrent with an enhancement in the <span class="hlt">solar</span> <span class="hlt">wind</span> measured by the ACE satellite. The <span class="hlt">solar</span> <span class="hlt">wind</span> enhancement reaches a flux level an order of magnitude more intense than typical fluxes at 1 AU, and has ion ratios with significantly enhanced higher ionization states. Whereas observations of the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma made at a single point reflect only local conditions which may only be representative of <span class="hlt">solar</span> <span class="hlt">wind</span> properties with spatial scales ranging from less than half of an Earth radii (approximately 10 s) to 100 Earth radii, X-ray observations of <span class="hlt">solar</span> <span class="hlt">wind</span> charge exchange are remote sensing measurements which may provide observations which are significantly more global in character. Besides being of interest in its own right for studies of the <span class="hlt">solar</span> system, this emission can have significant consequences for observations of more cosmological objects. It can provide emission lines at zero redshift which are of particular interest (e.g., O VII and O VIII) in studies of diffuse thermal emission, and which can therefore act as contamination in objects which cover the entire detector field of view. We propose the use of <span class="hlt">solar</span> <span class="hlt">wind</span> monitoring data, such as from the ACE and <span class="hlt">Wind</span> spacecraft, as a diagnostic to screen for such possibilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19840050402&hterms=entropy+symmetry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dentropy%2Bsymmetry','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19840050402&hterms=entropy+symmetry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dentropy%2Bsymmetry"><span id="translatedtitle">A hydromagnetic model of corotating conductive <span class="hlt">solar</span> <span class="hlt">wind</span> streams</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Yeh, T.</p> <p>1984-01-01</p> <p>Under the assumption of quasi-azimuthal symmetry the governing equations of a steady hydromagnetic flow in a thermally conductive flux tube possess six invariants. Four of them represent constancy of mass efflux, energy efflux, angular momentum efflux and magnetic flux. Based on the entropy equation we obtain useful approximation in explicit expressions for the two remaining invariants. One of them provides the constraint which determines the compatible heat flux to ensure a vanishing pressure at infinity. Thus, the admissible solution that represents a corotating <span class="hlt">solar</span> <span class="hlt">wind</span> stream in terms of specified interplanetary condition can be calculated by an algebraic method, without the necessity of numerical integration. A two-point relationship is then derived, which correlates the <span class="hlt">solar</span> <span class="hlt">wind</span> properties at two separated interplanetary sites measured at two properly separated instants. This relationship may be applied to observational data from spacecraft and earth-bound satellites to discern the corotation feature in the <span class="hlt">solar</span> <span class="hlt">wind</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19720035478&hterms=Magnetism&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMagnetism','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19720035478&hterms=Magnetism&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMagnetism"><span id="translatedtitle">Lunar fossil magnetism and perturbations of the <span class="hlt">solar</span> <span class="hlt">wind</span>.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sonett, C. P.; Mihalov, J. D.</p> <p>1972-01-01</p> <p>Perturbations of the <span class="hlt">solar</span> <span class="hlt">wind</span> downstream of the moon and lying outside of the rarefaction wave that defines the diamagnetic cavity are used to define possible source regions comprised of intrinsically magnetized areas of the moon. A map of the moon is constructed showing that a model in which the sources are exposed to the grazing <span class="hlt">solar</span> <span class="hlt">wind</span> during the lunation yields a selenographically invariant set of regions strongly favoring the lunar highlands over the maria. An alternative model with the source due to electromagnetic induction is explored. The ages of the field sources should be consistent with those based on the basalt ages and possibly far older if the sources are connected with the formation of the highland rocks themselves. The perturbations are tentatively identified as weak shock waves, and a Mach angle in accord with nominal values for the <span class="hlt">solar</span> <span class="hlt">wind</span> is found.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19810055592&hterms=solar+energy+facts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Benergy%2Bfacts','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19810055592&hterms=solar+energy+facts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Benergy%2Bfacts"><span id="translatedtitle">Energy coupling between the <span class="hlt">solar</span> <span class="hlt">wind</span> and the magnetosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Akasofu, S.-I.</p> <p>1981-01-01</p> <p>A description is given of the path leading to the first approximation expression for the <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere energy coupling function (epsilon), which correlates well with the total energy consumption rate (U sub T) of the magnetosphere. It is shown that epsilon is the primary factor controlling the time development of magnetospheric substorms and storms. The finding of this particular expression epsilon indicates how the <span class="hlt">solar</span> <span class="hlt">wind</span> couples its energy to the magnetosphere; the <span class="hlt">solar</span> <span class="hlt">wind</span> and the magnetosphere make up a dynamo. In fact, the power generated by the dynamo can be identified as epsilon through the use of a dimensional analysis. In addition, the finding of epsilon suggests that the magnetosphere is closer to a directly driven system than to an unloading system which stores the generated energy before converting it to substorm and storm energies. The finding of epsilon and its implications is considered to have significantly advanced and improved the understanding of magnetospheric processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22364020','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22364020"><span id="translatedtitle">PROTON KINETIC EFFECTS IN VLASOV AND <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> TURBULENCE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Servidio, S.; Valentini, F.; Perrone, D.; Veltri, P.; Osman, K. T.; Chapman, S.; Califano, F.; Matthaeus, W. H.</p> <p>2014-02-01</p> <p>Kinetic plasma processes are investigated in the framework of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence, employing hybrid Vlasov-Maxwell (HVM) simulations. Statistical analysis of spacecraft observation data relates proton temperature anisotropy T /T {sub ?} and parallel plasma beta ?{sub ?}, where subscripts refer to the ambient magnetic field direction. Here, this relationship is recovered using an ensemble of HVM simulations. By varying plasma parameters, such as plasma beta and fluctuation level, the simulations explore distinct regions of the parameter space given by T /T {sub ?} and ?{sub ?}, similar to <span class="hlt">solar</span> <span class="hlt">wind</span> sub-datasets. Moreover, both simulation and <span class="hlt">solar</span> <span class="hlt">wind</span> data suggest that temperature anisotropy is not only associated with magnetic intermittent events, but also with gradient-type structures in the flow and in the density. This connection between non-Maxwellian kinetic effects and various types of intermittency may be a key point for understanding the complex nature of plasma turbulence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19740034914&hterms=wind+moon&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dwind%2Bmoon','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19740034914&hterms=wind+moon&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dwind%2Bmoon"><span id="translatedtitle">Magnetic measurements of the <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with the moon</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lichtenstein, B. R.; Coleman, P. J., Jr.; Russell, C. T.</p> <p>1973-01-01</p> <p>The magnetic signature of the interaction between the moon and the <span class="hlt">solar</span> <span class="hlt">wind</span> (as observed by the Apollo 15 subsatellite) is an enhanced field directly behind the moon, bounded on either side by two dips in the field strength. On occasion, compressions of the field strength are observed external to either one or sometimes both of these dips. Theories of the interaction postulate either that these compressions are a general feature of the <span class="hlt">solar</span> <span class="hlt">wind</span>-moon interaction modulated by changes in the <span class="hlt">solar</span> <span class="hlt">wind</span> parameters or that they are associated with the appearance of specific lunar regions at the limbs. The measurements of the lunar magnetic field with the Apollo 15 and 16 subsatellites, the mapping of projected source positions of limb compressions onto the lunar surface, and the study of the persistence of limb compressions supports the hypothesis that limb compressions are formed when regions of high magnetization are at the lunar limbs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSH22B..06E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSH22B..06E"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> Observations from 10 to 30 AU Measured With The New Horizons <span class="hlt">Solar</span> <span class="hlt">Wind</span> Around Pluto (SWAP) Instrument</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Elliott, H. A.; McComas, D. J.; Valek, P. W.; Nicolaou, G.; Bagenal, F.; Delamere, P. A.; Livadiotis, G.</p> <p>2014-12-01</p> <p>Beginning in 2012 the New Horizons mission to Pluto began collecting <span class="hlt">solar</span> <span class="hlt">wind</span> observations during the spacecraft hibernation greatly increasing the <span class="hlt">solar</span> <span class="hlt">wind</span> coverage. We have extensively analyzed both the laboratory and flight calibration measurements for the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Around Pluto (SWAP) instrument to produce a data set of <span class="hlt">solar</span> <span class="hlt">wind</span> observations at times when the New Horizons spacecraft is spinning. This full data set spans from 10 to 30 AU, and the improved coverage portion spans from 20- 30 AU. Coincidently, in 2012 and 2013 the ACE, STEREO A, and STEREO B were well separated in longitude. We compare the New Horizons speeds with propagated 1 AU speed measurements, and find many of the largest scale structures persist beyond 20 AU. The New Horizons <span class="hlt">solar</span> <span class="hlt">wind</span> coverage between 20 and 30 AU is now extensive enough to examine the temperature-speed relationship and compare that to the relationship found in the inner heliosphere and to that in the Voyager 2 observations. Upon initial examination we also find a temperature-speed relationship that persists in the 20-30 AU distance range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSH43A..03W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSH43A..03W"><span id="translatedtitle">Turbulent Heating and Wave Pressure in <span class="hlt">Solar</span> <span class="hlt">Wind</span> Acceleration Modeling: New Insights to Empirical Forecasting of the <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Woolsey, L. N.; Cranmer, S. R.</p> <p>2013-12-01</p> <p>The study of <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration has made several important advances recently due to improvements in modeling techniques. Existing code and simulations test the competing theories for coronal heating, which include reconnection/loop-opening (RLO) models and wave/turbulence-driven (WTD) models. In order to compare and contrast the validity of these theories, we need flexible tools that predict the emergent <span class="hlt">solar</span> <span class="hlt">wind</span> properties from a wide range of coronal magnetic field structures such as coronal holes, pseudostreamers, and helmet streamers. ZEPHYR (Cranmer et al. 2007) is a one-dimensional magnetohydrodynamics code that includes Alfven wave generation and reflection and the resulting turbulent heating to accelerate <span class="hlt">solar</span> <span class="hlt">wind</span> in open flux tubes. We present the ZEPHYR output for a wide range of magnetic field geometries to show the effect of the magnetic field profiles on <span class="hlt">wind</span> properties. We also investigate the competing acceleration mechanisms found in ZEPHYR to determine the relative importance of increased gas pressure from turbulent heating and the separate pressure source from the Alfven waves. To do so, we developed a code that will become publicly available for <span class="hlt">solar</span> <span class="hlt">wind</span> prediction. This code, TEMPEST, provides an outflow solution based on only one input: the magnetic field strength as a function of height above the photosphere. It uses correlations found in ZEPHYR between the magnetic field strength at the source surface and the temperature profile of the outflow solution to compute the <span class="hlt">wind</span> speed profile based on the increased gas pressure from turbulent heating. With this initial solution, TEMPEST then adds in the Alfven wave pressure term to the modified Parker equation and iterates to find a stable solution for the <span class="hlt">wind</span> speed. This code, therefore, can make predictions of the <span class="hlt">wind</span> speeds that will be observed at 1 AU based on extrapolations from magnetogram data, providing a useful tool for empirical forecasting of the sol! ar <span class="hlt">wind</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.P43B1431F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.P43B1431F"><span id="translatedtitle">Strong interaction between Phobos and the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Futaana, Y.; Barabash, S.; Holmstrom, M.; Nilsson, H.; Lundin, R.</p> <p>2009-12-01</p> <p>During the Mars Express (MEX) closest approach to Phobos on July 23, 2008, the ASPERA-3/IMA (Ion Mass Analyser) sensor on board MEX carried out ion observations. The approach was in the upstream <span class="hlt">solar</span> <span class="hlt">wind</span>, and IMA detected unusual signatures of the proton fluxes close to Phobos apart from the commonly seen bow shock signatures. Because MEX has no magnetometer on board it is not possible to directly back trace the trajectories of the observed protons. Thus, it was not easy to confirm if those protons came from Phobos. However, after a careful analysis, we conclude that the origin of these protons is indeed Phobos. The reasons are: 1. The energy of the observed protons is slightly less than the <span class="hlt">solar</span> <span class="hlt">wind</span> proton energy, and the energy spectrum have a low-energy tail. The protons behave as backscattered <span class="hlt">solar</span> <span class="hlt">wind</span> protons which was reported by the Japanese Kaguya mission at the Moon. 2. We conducted test particle backtracing assuming that the protons originate from Phobos under various magnetic field conditions. A consistent solution for all independent observations was found. 3. We looked through all the IMA data observed in the undisturbed <span class="hlt">solar</span> <span class="hlt">wind</span>, and found that the strong signals were only observed during the Phobos flyby. These analyses indicate that Phobos is the most probable source of the observed protons during the flyby. Even though the generation mechanism is not fully understood, by taking Kaguya observation close to Moon as an analogy, the observed protons close to Phobos are most probably <span class="hlt">solar</span> <span class="hlt">wind</span> protons backscattered from Phobos. The process of backscattering of impinging keV particles has never been considered because most of the particles have been assumed to be absorbed at the very rough surface of the regolith. However, these investigations suggest that the backscattering of the <span class="hlt">solar</span> <span class="hlt">wind</span> protons are a general feature of the atmosphereless body covered by regolith, which would be applicable to Mercury, meteorite, and moons of giant planets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1167251','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1167251"><span id="translatedtitle">Agua Caliente <span class="hlt">Wind/Solar</span> Project at Whitewater Ranch</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hooks, Todd; Stewart, Royce</p> <p>2014-12-16</p> <p>Agua Caliente Band of Cahuilla Indians (ACBCI) was awarded a grant by the Department of Energy (DOE) to study the feasibility of a <span class="hlt">wind</span> and/or <span class="hlt">solar</span> renewable energy project at the Whitewater Ranch (WWR) property of ACBCI. Red Mountain Energy Partners (RMEP) was engaged to conduct the study. The ACBCI tribal lands in the Coachella Valley have very rich renewable energy resources. The tribe has undertaken several studies to more fully understand the options available to them if they were to move forward with one or more renewable energy projects. With respect to the resources, the WWR property clearly has excellent <span class="hlt">wind</span> and <span class="hlt">solar</span> resources. The DOE National Renewable Energy Laboratory (NREL) has continued to upgrade and refine their library of resource maps. The newer, more precise maps quantify the resources as among the best in the world. The <span class="hlt">wind</span> and <span class="hlt">solar</span> technology available for deployment is also being improved. Both are reducing their costs to the point of being at or below the costs of fossil fuels. Technologies for energy storage and microgrids are also improving quickly and present additional ways to increase the <span class="hlt">wind</span> and/or <span class="hlt">solar</span> energy retained for later use with the network management flexibility to provide power to the appropriate locations when needed. As a result, renewable resources continue to gain more market share. The transitioning to renewables as the major resources for power will take some time as the conversion is complex and can have negative impacts if not managed well. While the economics for <span class="hlt">wind</span> and <span class="hlt">solar</span> systems continue to improve, the robustness of the WWR site was validated by the repeated queries of developers to place <span class="hlt">wind</span> and/or <span class="hlt">solar</span> there. The robust resources and improving technologies portends toward WWR land as a renewable energy site. The business case, however, is not so clear, especially when the potential investment portfolio for ACBCI has several very beneficial and profitable alternatives.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/astro-ph/0511006v8','EPRINT'); return false;" href="http://arxiv.org/pdf/astro-ph/0511006v8"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Winds</span> Driven by Nonlinear Low-Frequency Alfven Waves from the Photosphere : Parametric Study for Fast/Slow <span class="hlt">Winds</span> and Disappearance of <span class="hlt">Solar</span> <span class="hlt">Winds</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Takeru K. Suzuki; Shu-ichiro Inutsuka</p> <p>2006-05-22</p> <p>(abridged) We investigate how the properties of the corona and <span class="hlt">solar</span> <span class="hlt">wind</span> in the open coronal holes depend on the properties of the magnetic fields and their footpoint motions at the surface, by perfoming 1D MHD simulations from the photosphere to 0.3 or 0.1AU. We impose low-frequency (<span class="hlt">solar</span> <span class="hlt">wind</span> is the universal consequence. The atmosphere is also stably heated up to >10^6K by the dissipation of the Alfven waves through compressive-wave generation and wave reflection in the case of the sufficient wave input with photospheric amplitude, > 0.7km/s. The density, and accordingly the mass flux, of <span class="hlt">solar</span> <span class="hlt">winds</span> show a quite sensitive dependence on because of an unstable aspect of the heating by the nonlinear Alfven waves. A case with =0.4km/s gives ~50 times smaller mass flux than the fiducial case for the fast <span class="hlt">wind</span> with =0.7km/s; <span class="hlt">solar</span> <span class="hlt">wind</span> almost disappears only if becomes half. We also find that the <span class="hlt">solar</span> <span class="hlt">wind</span> speed has a positive correlation with B/f_max, which is consistent with recent observations. We finally show that both fast and slow <span class="hlt">solar</span> <span class="hlt">winds</span> can be explained by the single process, the dissipation of the low-frequency Alfven waves, with different sets of and B/f_max. Our simulations naturally explain the observed (i) anticorrelation of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed and the coronal temperature and (ii) larger amplitude of the Alfvenic fluctuations in the fast <span class="hlt">winds</span>. In Appendix, we also explain our implementation of the outgoing boundary condition of the MHD waves with some numerical tests.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17994092','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17994092"><span id="translatedtitle">Modulation of Saturn's radio clock by <span class="hlt">solar</span> <span class="hlt">wind</span> speed.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zarka, Philippe; Lamy, Laurent; Cecconi, Baptiste; Prangé, Renée; Rucker, Helmut O</p> <p>2007-11-01</p> <p>The internal rotation rates of the giant planets can be estimated by cloud motions, but such an approach is not very precise because absolute <span class="hlt">wind</span> speeds are not known a priori and depend on latitude: periodicities in the radio emissions, thought to be tied to the internal planetary magnetic field, are used instead. Saturn, despite an apparently axisymmetric magnetic field, emits kilometre-wavelength (radio) photons from auroral sources. This emission is modulated at a period initially identified as 10 h 39 min 24 +/- 7 s, and this has been adopted as Saturn's rotation period. Subsequent observations, however, revealed that this period varies by +/-6 min on a timescale of several months to years. Here we report that the kilometric radiation period varies systematically by +/-1% with a characteristic timescale of 20-30 days. Here we show that these fluctuations are correlated with <span class="hlt">solar</span> <span class="hlt">wind</span> speed at Saturn, meaning that Saturn's radio clock is controlled, at least in part, by conditions external to the planet's magnetosphere. No correlation is found with the <span class="hlt">solar</span> <span class="hlt">wind</span> density, dynamic pressure or magnetic field; the <span class="hlt">solar</span> <span class="hlt">wind</span> speed therefore has a special function. We also show that the long-term fluctuations are simply an average of the short-term ones, and therefore the long-term variations are probably also driven by changes in the <span class="hlt">solar</span> <span class="hlt">wind</span>. PMID:17994092</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22118611','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22118611"><span id="translatedtitle">The turbulent cascade and proton heating in the <span class="hlt">solar</span> <span class="hlt">wind</span> during <span class="hlt">solar</span> minimum</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Coburn, Jesse T.; Smith, Charles W.; Vasquez, Bernard J.; Stawarz, Joshua E.; Forman, Miriam A.</p> <p>2013-06-13</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> measurements at 1 AU during the recent <span class="hlt">solar</span> minimum and previous studies of <span class="hlt">solar</span> maximum provide an opportunity to study the effects of the changing <span class="hlt">solar</span> cycle on in situ heating. Our interest is to compare the levels of activity associated with turbulence and proton heating. Large-scale shears in the flow caused by transient activity are a source that drives turbulence that heats the <span class="hlt">solar</span> <span class="hlt">wind</span>, but as the <span class="hlt">solar</span> cycle progresses the dynamics that drive the turbulence and heat the medium are likely to change. The application of third-moment theory to Advanced Composition Explorer (ACE) data gives the turbulent energy cascade rate which is not seen to vary with the <span class="hlt">solar</span> cycle. Likewise, an empirical heating rate shows no significan changes in proton heating over the cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015DPS....4710006B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015DPS....4710006B"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> interaction with Pluto’s escaping atmosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bagenal, Fran; Stern, S. A.; Weaver, H. A.; Young, L. A.; Ennico, K.; Olkin, C.; McComas, D. J.; McNutt, R. L.; Horanyi, M.; Elliott, H. A.; Hill, M. E.; Zernstein, E.; Kollman, P.; Krimigis, S. M.; Lisse, C. M.; Strobel, D. F.; SzalAy, J.; Piquette, M.</p> <p>2015-11-01</p> <p>NASA’s New Horizons spacecraft carries two instruments, SWAP and PEPSSI, that measure low and high energy particles respectively. These particle instruments have been measuring the conditions in the <span class="hlt">solar</span> <span class="hlt">wind</span> for most of the trajectory from Earth to Pluto. The Venetia Burney Student Dust Counter measured impacts from micron-sixed dust particles. These particle instruments also made observations during the flyby of Pluto on July 14, 2015. We report on New Horizons measurements of the interaction of the <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with Pluto’s extended atmosphere and discuss comparisons with theoretical expectations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20070021568&hterms=wind+work+you&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dwind%2Bwork%2Byou','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20070021568&hterms=wind+work+you&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dwind%2Bwork%2Byou"><span id="translatedtitle">Measurement of Damage Profiles from <span class="hlt">Solar</span> <span class="hlt">Wind</span> Implantation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McNamara, K. M.; Synowicki, R. A.; Tiwald, T. E.</p> <p>2007-01-01</p> <p>NASA's Genesis Mission launched from Cape Canaveral in August of 2001 with the goal of collecting <span class="hlt">solar</span> <span class="hlt">wind</span> in ultra-pure materials. The samples were returned to Earth more than three years later for subsequent analysis. Although the <span class="hlt">solar</span> <span class="hlt">wind</span> is comprised primarily of protons, it also contains ionized species representing the entire periodic table. The Genesis mission took advantage of the natural momentum of these ionized species to implant themselves in specialized collectors including single crystal Si and SiC. The collectors trapped the <span class="hlt">solar</span> <span class="hlt">wind</span> species of interest and sustained significant damage to the surface crystal structure as a result of the ion bombardment. In this work, spectroscopic ellipsometry has been used to evaluate the extent of this damage in Si and SiC samples. These results and models are compared for artificially implanted samples and pristine non-flight material. In addition, the flown samples had accumulated a thin film of molecular contamination as a result of outgassing in flight, and we demonstrate that this layer can be differentiated from the material damage. In addition to collecting bulk <span class="hlt">solar</span> <span class="hlt">wind</span> samples (continuous exposure), the Genesis mission actually returned silicon exposed to four different <span class="hlt">solar</span> <span class="hlt">wind</span> regimes: bulk, high speed, low speed, and coronal mass ejections. Each of these <span class="hlt">solar</span> <span class="hlt">wind</span> regimes varies in energy, but may vary in composition as well. While determining the composition is a primary goal of the mission, we are also interested in the variation in depth and extent of the damage layer as a function of <span class="hlt">solar</span> <span class="hlt">wind</span> regime. Here, we examine flight Si from the bulk <span class="hlt">solar</span> <span class="hlt">wind</span> regime and compare the results to both pristine and artificially implanted Si. Finally, there were four samples which were mounted in an electrostatic "concentrator" designed to reject a large fraction (>85%) of incoming protons while enhancing the concentration of ions mass 4-28 amu by a factor of at least 20. Two of these samples were single crystal 6H silicon carbide. (The others were polycrystalline CVD diamond and amorphous carbon that were not examined in the work.) The ion damaged SiC samples from the concentrator were studied in comparison to the flight Si from the bulk array to understand differences in the extent of the damage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/574650','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/574650"><span id="translatedtitle">Electron energy transport in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Ulysses observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Scime, E.E.; Gary, S.P.; Phillips, J.L.; Balogh, A.; Lengyel-Frey, D.</p> <p>1996-07-01</p> <p>Previous analysis suggests that the whistler heat flux instability is responsible for the regulation of the electron heat flux of the <span class="hlt">solar</span> <span class="hlt">wind</span>. For an interval of quiescent <span class="hlt">solar</span> <span class="hlt">wind</span> during the in-ecliptic phase of the Ulysses mission, the plasma wave data in the whistler frequency regime are compared to the predictions of the whistler heat flux instability model. The data is well constrained by the predicted upper bound on the electron heat flux and a clear correlation between wave activity and electron heat flux dissipation is observed. {copyright} {ital 1996 American Institute of Physics.}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990014460','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990014460"><span id="translatedtitle">Interpretation of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Composition Measurements from Ulysses</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Esser, Ruth</p> <p>1999-01-01</p> <p>Ion charge states measured in situ in interplanetary space carry information on the properties of the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma in the inner corona. This information is, however, not easy to extract from the in situ observations. The goal of the proposal was to determine <span class="hlt">solar</span> <span class="hlt">wind</span> models and coronal observations that are necessary tools for the interpretation of charge state observations. It has been shown that the interpretation of the in situ ion fractions are heavily dependent on the assumptions about conditions in the inner corona.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21371710','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21371710"><span id="translatedtitle">Compressive turbulent cascade and heating in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Marino, R.; Sorriso-Valvo, L.; Noullez, A.; Bruno, R.</p> <p>2010-03-25</p> <p>A turbulent energy cascade has been recently identified in high-latitude <span class="hlt">solar</span> <span class="hlt">wind</span> data samples by using a Yaglom-like relation. However, analogous scaling law, suitably modified to take into account compressible fluctuations, has been observed in a much more extended fraction of the same data set recorded by the Ulysses spacecraft. Thus, it seems that large scale density fluctuations, despite their low amplitude, play a major role in the basic scaling properties of turbulence. The compressive turbulent cascade, moreover, seems to be able to supply the energy needed to account for the local heating of the non-adiabatic <span class="hlt">solar</span> <span class="hlt">wind</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21163474','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21163474"><span id="translatedtitle">Electron energy transport in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Ulysses observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Scime, Earl E.; Gary, S. Peter; Phillips, John L.; Balogh, Andre; Lengyel-Frey, Denise</p> <p>1996-07-20</p> <p>Previous analysis suggests that the whistler heat flux instability is responsible for the regulation of the electron heat flux of the <span class="hlt">solar</span> <span class="hlt">wind</span>. For an interval of quiescent <span class="hlt">solar</span> <span class="hlt">wind</span> during the in-ecliptic phase of the Ulysses mission, the plasma wave data in the whistler frequency regime are compared to the predictions of the whistler heat flux instability model. The data is well constrained by the predicted upper bound on the electron heat flux and a clear correlation between wave activity and electron heat flux dissipation is observed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008cosp...37..568C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008cosp...37..568C"><span id="translatedtitle">Synoptic MHD model for the Ambient <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cohen, Ofer; Sokolov, Igor; Gombosi, Tamas; Roussev, Ilia; Manchester, Ward, IV; Frazin, Richard</p> <p></p> <p>We present a global, 3D MagnetoHydroDynamic model for the <span class="hlt">solar</span> corona and the <span class="hlt">solar</span> <span class="hlt">wind</span>. The model is driven by high resolution MDI magnetograms and is constrained by the empirical Wang-Sheeley-Arge (WSA) model. The model provides the three-dimensional steady state structure of the heliosphere between the Sun and the Earth for a particular Carrington Rotation. We compare the model's result for coronal electron density with electron density extracted using tomographic reconstruction. We also validate the model by comparing its result with long-term ACE and <span class="hlt">WIND</span> data, as well as STEREO data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19770067670&hterms=Bohr+Niels&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2528Bohr%2BNiels%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19770067670&hterms=Bohr+Niels&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2528Bohr%2BNiels%2529"><span id="translatedtitle">Mass fractionation of the lunar surface by <span class="hlt">solar</span> <span class="hlt">wind</span> sputtering</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Switkowski, Z. E.; Haff, P. K.; Tombrello, T. A.; Burnett, D. S.</p> <p>1977-01-01</p> <p>An investigation is conducted concerning the mass-fractionation effects produced in connection with the bombardment of the moon by the <span class="hlt">solar</span> <span class="hlt">wind</span>. Most of the material ejected by sputtering escapes the moon's gravity, but some returning matter settles back onto the lunar surface. This material, which is somewhat richer in heavier atoms than the starting surface, is incorporated into the heavily radiation-damaged outer surfaces of grains. The investigation indicates that sputtering of the lunar surface by the <span class="hlt">solar</span> <span class="hlt">wind</span> will give rise to significant surface heavy atom enrichments if the grain surfaces are allowed to come into sputtering equilibrium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19850041177&hterms=1055&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2526%25231055','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19850041177&hterms=1055&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2526%25231055"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> control of magnetospheric pressure (CDAW 6)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fairfield, D. H.</p> <p>1985-01-01</p> <p>The CDAW 6 data base is used to compare <span class="hlt">solar</span> <span class="hlt">wind</span> and magnetospheric pressures. The flaring angle of the tail magnetopause is determined by assuming that the component of <span class="hlt">solar</span> <span class="hlt">wind</span> pressure normal to the tail boundary is equal to the total pressure within the tail. Results indicate an increase in the tail flaring angle from 18 deg to 32 deg prior to the 1055 substorm onset and a decrease to 25 deg after the onset. This behavior supports the concept of tail energy storage before the substorm and subsequent release after the onset.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22181719','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22181719"><span id="translatedtitle">Modified temperature-anisotropy instability thresholds in the <span class="hlt">solar</span> <span class="hlt">wind</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schlickeiser, R; Michno, M J; Ibscher, D; Lazar, M; Skoda, T</p> <p>2011-11-11</p> <p>The proton and electron temperature anisotropies in the <span class="hlt">solar</span> <span class="hlt">wind</span> are constrained by the instability thresholds for temperature-anisotropy-driven kinetic plasma instabilities. The modifications to the marginal instability conditions from accounting for the influence of damping connected with the collisional effects in the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma are calculated for right- and left-handed polarized parallel propagating Alfvén waves and mirror and firehose fluctuations. These modifications provide tighter threshold constraints compared to the marginal thresholds but do not fully explain the observations at small values of the parallel plasma beta. PMID:22181719</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22365363','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22365363"><span id="translatedtitle">CORE ELECTRON HEATING IN <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> RECONNECTION EXHAUSTS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pulupa, M. P.; Salem, C.; Phan, T. D.; Bale, S. D.; Gosling, J. T.</p> <p>2014-08-10</p> <p>We present observational evidence of core electron heating in <span class="hlt">solar</span> <span class="hlt">wind</span> reconnection exhausts. We show two example events, one which shows clear heating of the core electrons within the exhaust, and one which demonstrates no heating. The event with heating occurred during a period of high inflow Alfvén speed (V {sub AL}), while the event with no heating had a low V {sub AL}. This agrees with the results of a recent study of magnetopause exhausts, and suggests that similar core electron heating can occur in both symmetric (<span class="hlt">solar</span> <span class="hlt">wind</span>) and asymmetric (magnetopause) exhausts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22252082','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22252082"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> kinetic instabilities at small plasma betas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ibscher, D. Schlickeiser, R.</p> <p>2014-02-15</p> <p>The ordinary perpendicular mode of drifting bi-Maxwellian plasma particle distributions with and without temperature anisotropy can provide aperiodic instabilities. These instabilities occur if the perpendicular thermal energy is much smaller than the streaming energy. This provides instabilities at small parallel plasma betas ?{sub ?}<1 and temperature anisotropies A?<?1. In this regime, the <span class="hlt">solar</span> <span class="hlt">wind</span> is unstable, which cannot be explained so far. To clarify if the ordinary perpendicular mode can be responsible for this instability, here we compare measurements in the <span class="hlt">solar</span> <span class="hlt">wind</span> with the instability provided by this mode.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EPSC....8..345B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EPSC....8..345B"><span id="translatedtitle">Gullies and the <span class="hlt">latitude</span> <span class="hlt">dependant</span> mantle: comparing Terra Cimmeria & Argyre Planitia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Britton, A.; Conway, S. J.; Balme, M.</p> <p>2013-09-01</p> <p>"Follow the water" has been an important theme for exploration of Mars. Under current atmospheric conditions, liquid water is only metastable at the surface. Using high-resolution images of Mars, we see kilometer-scale features with an alcove, channel and a debris apron - "gullies". These gullies resemble water-carved steepland channels on Earth [1, 12]. Previous global-scale studies covering both hemispheres of Mars have been conducted [2, 8-10], but using datasets with limited coverage, but as highresolution coverage of the planet continues to grow, full-coverage, global-scale studies become possible. Previous work has shown that gullies are common in the mid-latitudes and show variation in slope-face orientation with respect to latitude [2,9-11]. The variations in orientation are suggested to result from obliquity driven climate change [7], whereby when Mars' axial tilt is large, the average daytime temperatures are sufficient for melting of nearsurface ice to occur. Previous work [4, 14] has suggested that gullies may originate from the melting of a surface unit known as <span class="hlt">latitude-dependent</span> mantle (LDM). LDM is interpreted to be rich in ice and dust and was deposited during previous glacial epochs [14]. The method by which gullies form, their associations to LDM and relations to recent ice ages are still under debate. We will analyze the relationship between gullies and LDM by comparing two regions: (1) Terra Cimmeria where gullies are not always associated with the LDM and (2) Argyre Planitia, where gullies are almost always associated with the LDM [6]. We will compare gullydistribution, orientation, and topographic properties (e.g. slope) between these areas. Here we report on the first results: the Terra Cimmeria study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21394447','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21394447"><span id="translatedtitle">CHARACTERIZATION OF TRANSITIONS IN THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> PARAMETERS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Perri, S.; Balogh, A. E-mail: a.balogh@imperial.ac.u</p> <p>2010-02-20</p> <p>The distinction between fast and slow <span class="hlt">solar</span> <span class="hlt">wind</span> streams and the dynamically evolved interaction regions is reflected in the characteristic fluctuations of both the <span class="hlt">solar</span> <span class="hlt">wind</span> and the embedded magnetic field. High-resolution magnetic field data from the Ulysses spacecraft have been analyzed. The observations show rapid variations in the magnetic field components and in the magnetic field strength, suggesting a structured nature of the <span class="hlt">solar</span> <span class="hlt">wind</span> at small scales. The typical sizes of fluctuations cover a broad range. If translated to the <span class="hlt">solar</span> surface, the scales span from the size of granules ({approx}10{sup 3} km) and supergranules ({approx}10{sup 4} km) on the Sun down to {approx}10{sup 2} km and less. The properties of the short time structures change in the different types of <span class="hlt">solar</span> <span class="hlt">wind</span>. While fluctuations in fast streams are more homogeneous, slow streams present a bursty behavior in the magnetic field variances, and the regions of transition are characterized by high levels of power in narrow structures around the transitions. The probability density functions of the magnetic field increments at several scales reveal a higher level of intermittency in the mixed streams, which is related to the presence of well localized features. It is concluded that, apart from the differences in the nature of fluctuations in flows of different coronal origin, there is a small-scale structuring that depends on the origin of streams themselves but it is also related to a bursty generation of the fluctuations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22167206','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22167206"><span id="translatedtitle">ACCELERATION OF THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> BY ALFVEN WAVE PACKETS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Galinsky, V. L.; Shevchenko, V. I.</p> <p>2013-01-20</p> <p>A scale separation kinetic model of the <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration is presented. The model assumes an isotropic Maxwellian distribution of protons and a constant influx of outward propagating Alfven waves with a single exponent Kolmogorov-type spectrum at the base of a coronal acceleration region ({approx}2 R {sub Sun }). Our results indicate that nonlinear cyclotron resonant interaction taking energy from Alfven waves and depositing it into mostly perpendicular heating of protons in initially weakly expanding plasma in a spherically non-uniform magnetic field is able to produce the typical fast <span class="hlt">solar</span> <span class="hlt">wind</span> velocities for the typical plasma and wave conditions after expansion to about 5-10 <span class="hlt">solar</span> radii R {sub Sun }. The acceleration model takes into account the gravity force and the ambipolar electric field, as well as the mirror force, which plays the most important role in driving the <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration. Contrary to the recent claims of Isenberg, the cold plasma dispersion only slightly slows down the acceleration and actually helps in obtaining the more realistic fast <span class="hlt">solar</span> <span class="hlt">wind</span> speeds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880001374','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880001374"><span id="translatedtitle">Study of the mechanism for <span class="hlt">solar</span> <span class="hlt">wind</span> formation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eselevich, V. G.; Filippov, M. A.</p> <p>1987-01-01</p> <p>Observations of the corona and <span class="hlt">solar</span> <span class="hlt">wind</span> are analyzed and compared with generalized results derived from laboratory-scale experiments. It was shown that a thermal pressure gradient can make a major contribution to a precipitating plasma of the <span class="hlt">solar</span> <span class="hlt">wind</span> emanating from coronal holes. It is found that the divergence Phi = (R/R sub <span class="hlt">solar</span> radius)f of the magnetic field lines, originating from coronal holes, is one of the factors governing <span class="hlt">solar</span> <span class="hlt">wind</span> velocity at Earth orbit (R= 1 AU). A decrease in the velocity V sub R = 1 AU from approx = 750 mk/sec down to approx = 450 km/sec may be attributable to an increase in superradial divergence f from approx = 7-9 to 20. The plasma energy flux density F at the base of the coronal holes representing the sources of the <span class="hlt">solar</span> <span class="hlt">wind</span> with V sub R=1AE = (450 to 750) km/sec, remains nearly constant, being F approx = (1.4 +/- 0.3) x 10 to the 6th power x ergs/sq cm/sec for the period 1973-1975.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AAS...22420302S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AAS...22420302S"><span id="translatedtitle">Origin of the Wang-Sheeley-Arge <span class="hlt">Solar</span> <span class="hlt">Wind</span> Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sheeley, Neil R.</p> <p>2014-06-01</p> <p>A correlation between <span class="hlt">solar</span> <span class="hlt">wind</span> speed at Earth and the amount of field line expansion in the corona was verified in 1989 using 22 years of <span class="hlt">solar</span> and interplanetary observations. This talk will trace the history of this discovery from its birth 15 years earlier in the Skylab era to its current use as a space weather forecasting technique. This research was supported by NASA and ONR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19740034906&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19740034906&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon"><span id="translatedtitle">The electric potential of the moon in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Freeman, J. W., Jr.; Fenner, M. A.; Hills, H. K.</p> <p>1973-01-01</p> <p>Acceleration and detection of the lunar thermal ionosphere in the presence of the lunar electric field yields a value of approximately +10 V for the lunar electric potential for <span class="hlt">solar</span> zenith angles between 20 and 45 deg and in the magnetosheath or <span class="hlt">solar</span> <span class="hlt">wind</span>. The ion number density of the thermal ionosphere observed is compatible with a surface neutral number density of about 100,000 atoms/cu cm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/0812.2568v1','EPRINT'); return false;" href="http://arxiv.org/pdf/0812.2568v1"><span id="translatedtitle">Anisotropic <span class="hlt">winds</span> from close-in extra-<span class="hlt">solar</span> planets</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>James M. Stone; Daniel Proga</p> <p>2008-12-13</p> <p>We present two-dimensional hydrodynamic models of thermally driven <span class="hlt">winds</span> from highly irradiated, close-in extra-<span class="hlt">solar</span> planets. We adopt a very simple treatment of the radiative heating processes at the base of the <span class="hlt">wind</span>, and instead focus on the differences between the properties of outflows in multidimensions in comparison to spherically symmetric models computed with the same methods. For hot (T > 2 x 10^{4} K) or highly ionized gas, we find strong (supersonic) polar flows are formed above the planet surface which produce weak shocks and outflow on the night-side. In comparison to a spherically symmetric <span class="hlt">wind</span> with the same parameters, the sonic surface on the day-side is much closer to the planet surface in multidimensions, and the total mass loss rate is reduced by almost a factor of four. We also compute the steady-state structure of interacting planetary and stellar <span class="hlt">winds</span>. Both <span class="hlt">winds</span> end in a termination shock, with a parabolic contact discontinuity which is draped over the planet separating the two shocked <span class="hlt">winds</span>. The planetary <span class="hlt">wind</span> termination shock and the sonic surface in the <span class="hlt">wind</span> are well separated, so that the mass loss rate from the planet is essentially unaffected. However, the confinement of the planetary <span class="hlt">wind</span> to the small volume bounded by the contact discontinuity greatly enhances the column density close to the planet, which might be important for the interpretation of observations of absorption lines formed by gas surrounding transiting planets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...801..100S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...801..100S"><span id="translatedtitle">On the Origin of Mid-latitude Fast <span class="hlt">Wind</span>: Challenging the Two-state <span class="hlt">Solar</span> <span class="hlt">Wind</span> Paradigm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stakhiv, Mark; Landi, Enrico; Lepri, Susan T.; Oran, Rona; Zurbuchen, Thomas H.</p> <p>2015-03-01</p> <p>The bimodal paradigm of <span class="hlt">solar</span> <span class="hlt">wind</span> describes a slow <span class="hlt">solar</span> <span class="hlt">wind</span> situated near the heliospheric current sheet while a fast <span class="hlt">wind</span> overexpands from the poles to fill in the remainder of the heliosphere. In this paper, we challenge this paradigm and focus here on mid-latitude <span class="hlt">wind</span> using three fast-latitude passes completed by the Ulysses spacecraft. Based on its composition and dynamic properties, we discuss how this <span class="hlt">wind</span> differs from both the fast, polar coronal hole <span class="hlt">wind</span> and the low latitude, streamer-associated slow <span class="hlt">solar</span> <span class="hlt">wind</span>. Using a detailed analysis of ionic and elemental abundances, as well as <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic properties, we conclude that there is a third quasi-stationary <span class="hlt">solar</span> <span class="hlt">wind</span> state, called the boundary <span class="hlt">wind</span>. This boundary <span class="hlt">wind</span> is characterized by a charge-state distribution that is similar to slow <span class="hlt">wind</span>, but with an elemental composition that is coronal hole like. Based on these data, we present arguments for the location of the origin of this <span class="hlt">wind</span>. We conclude that the boundary <span class="hlt">wind</span> is a subset of the fast <span class="hlt">wind</span> emanating from regions close to the boundaries of coronal holes and is accelerated by a similar process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.9652R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.9652R"><span id="translatedtitle">Comparison of <span class="hlt">solar</span> <span class="hlt">wind</span> driving of the aurora in the two hemispheres due to the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamo</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reistad, Jone Peter; Østgaard, Nikolai; Magnus Laundal, Karl; Haaland, Stein; Tenfjord, Paul; Oksavik, Kjellmar</p> <p>2014-05-01</p> <p>Event studies of simultaneous global imaging of the aurora in both hemispheres have suggested that an asymmetry of the <span class="hlt">solar</span> <span class="hlt">wind</span> driving between the two hemispheres could explain observations of non-conjugate aurora during specific driving conditions. North-South asymmetries in energy transfer from the <span class="hlt">solar</span> <span class="hlt">wind</span> across the magnetopause is believed to depend upon the dipole tilt angle and the x-component of the interplanetary magnetic field (IMF). Both negative tilt (winter North) and negative IMF Bx is expected to enhance the efficiency of the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamo in the Northern Hemisphere. By the same token, positive tilt and IMF Bx is expected to enhance the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamo efficiency in the Southern Hemisphere. We show a statistical study of the auroral response from both hemispheres using global imaging where we compare results during both favourable and not favourable conditions in each hemisphere. By this study we will address the question of general impact on auroral hemispheric asymmetries by this mechanism - the asymmetric <span class="hlt">solar</span> <span class="hlt">wind</span> dynamo. We use data from the Wideband Imaging Camera on the IMAGE spacecraft which during its lifetime from 2000-2005 covered both hemispheres. To ease comparison of the two hemispheres, seasonal differences in auroral brightness is removed as far as data coverage allows by only using events having small dipole tilt angles. Hence, the IMF Bx is expected to be the controlling parameter for the hemispheric preference of strongest <span class="hlt">solar</span> <span class="hlt">wind</span> dynamo efficiency in our dataset. Preliminary statistical results indicate the expected opposite behaviour in the two hemispheres, however, the effect is believed to be weak.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2013-12-23/pdf/2013-30518.pdf','FEDREG'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2013-12-23/pdf/2013-30518.pdf"><span id="translatedtitle">78 FR 77447 - California <span class="hlt">Wind</span> Energy Association, First <span class="hlt">Solar</span>, Inc. v. California Independent System Operator...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2013-12-23</p> <p>...DEPARTMENT OF ENERGY Federal Energy Regulatory Commission...EL14-14-000] California <span class="hlt">Wind</span> Energy Association, First <span class="hlt">Solar</span>, Inc. v. California Independent...2013), California <span class="hlt">Wind</span> Energy Association and First <span class="hlt">Solar</span>, Inc....</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www2.gi.alaska.edu/~chungsangng/bn_a_mhd-turb_aipcp03.pdf','EPRINT'); return false;" href="http://www2.gi.alaska.edu/~chungsangng/bn_a_mhd-turb_aipcp03.pdf"><span id="translatedtitle">Anisotropic MHD Turbulence in the Interstellar Medium and <span class="hlt">Solar</span> <span class="hlt">Wind</span> A. Bhattacharjee and C. S. Ng</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Ng, Chung-Sang</p> <p></p> <p>Anisotropic MHD Turbulence in the Interstellar Medium and <span class="hlt">Solar</span> <span class="hlt">Wind</span> A. Bhattacharjee and C. S. Ng turbulence in the interstellar medium and the <span class="hlt">solar</span> <span class="hlt">wind</span>. The model is motivated by observations that show</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20110016219&hterms=solar+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3D%2528solar%2Bwind%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20110016219&hterms=solar+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3D%2528solar%2Bwind%2529"><span id="translatedtitle">A Model fot the Sources of the Slow <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Antiochos, S. K.; Mikic, Z.; Titov, V. S.; Lionello, R.; Linker, J. A.</p> <p>2011-01-01</p> <p>Models for the origin of the slow <span class="hlt">solar</span> <span class="hlt">wind</span> must account for two seemingly contradictory observations: the slow <span class="hlt">wind</span> has the composition of the closed-field corona, implying that it originates from the continuous opening and closing of flux at the boundary between open and closed field. On the other hand, the slow <span class="hlt">wind</span> also has large angular width, up to approx.60deg, suggesting that its source extends far from the open-closed boundary. We propose a model that can explain both observations. The key idea is that the source of the slow <span class="hlt">wind</span> at the Sun is a network of narrow (possibly singular) open-field corridors that map to a web of separatrices and quasi-separatrix layers in the heliosphere. We compute analytically the topology of an open-field corridor and show that it produces a quasi-separatrix layer in the heliosphere that extends to angles far from the heliospheric current sheet. We then use an MHD code and MDI/SOHO observations of the photospheric magnetic field to calculate numerically, with high spatial resolution, the quasi-steady <span class="hlt">solar</span> <span class="hlt">wind</span>, and magnetic field for a time period preceding the 2008 August 1 total <span class="hlt">solar</span> eclipse. Our numerical results imply that, at least for this time period, a web of separatrices (which we term an S-web) forms with sufficient density and extent in the heliosphere to account for the observed properties of the slow <span class="hlt">wind</span>. We discuss the implications of our S-web model for the structure and dynamics of the corona and heliosphere and propose further tests of the model. Key words: <span class="hlt">solar</span> <span class="hlt">wind</span> - Sun: corona - Sun: magnetic topology</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012cosp...39.1229M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012cosp...39.1229M"><span id="translatedtitle">Electric <span class="hlt">Solar</span> <span class="hlt">Wind</span> Sail (E-sail) mission to asteroids</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Merikallio, Sini; Janhunen, Pekka; Toivanen, Petri; Jouni Envall, M.(Tech.).</p> <p>2012-07-01</p> <p>There are an estimated one to two million asteroids of diameter over 1 km in-between the orbits of Mars and Jupiter. Impact threat, mining prospects and the understanding of <span class="hlt">solar</span> system history make asteroids interesting objects for further in-situ studies. Electric <span class="hlt">Solar</span> <span class="hlt">Wind</span> Sail (E-sail) [1] technology enables touring several different asteroids with the same spacecraft. It is a propulsion technology first proposed in 2006 and currently developed with the EUs FP7 funding (http://www.electric-sailing.fi/fp7). The E-sail utilizes long, conducting, highly charged tethers to gather momentum from the <span class="hlt">solar</span> <span class="hlt">wind</span> ions. It does not consume any propellant and is well maneuverable. The Electric <span class="hlt">Solar</span> <span class="hlt">Wind</span> Sail producing 1 N of thrust at 1 AU distance from the Sun could be manufactured to weigh 100-150 kg in total. The constant acceleration gives a large advantage over traditional methods when calculated over the mission lifetime. In a ten year mission a baseline 1 N E-sail could produce 300 MNs of total impulse, Itot. As an example, such a total impulse would be able to move a 3 million ton Earth-threatening asteroid to a safer track [2]. With chemical propellant it would take 100 000 tons of fuel to achieve the same feat. Scientists and miners could have a closer look at several targets and they could decide the next target and the duration of investigations once at the vicinity of the asteroid, so the operations would be very flexible. Such a mission could characterize and map several asteroids, some with rapid fly-bys and a few chosen ones during lengthier rendezvous. [1] Janhunen, P., et. al, Electric <span class="hlt">solar</span> <span class="hlt">wind</span> sail: Towards test missions (Invited article), Rev. Sci. Instrum., 81, 111301, 2010. [2] Merikallio, S. and P. Janhunen, Moving an asteroid with electric <span class="hlt">solar</span> <span class="hlt">wind</span> sail, Astrophys. Space Sci. Trans., 6, 41-48, 2010</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20020069138&hterms=Ulysses&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DUlysses','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20020069138&hterms=Ulysses&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DUlysses"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> Characteristics from SOHO-Sun-Ulysses Quadrature Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Poletto, Giannina; Suess, Steve T.; Six, N. Frank (Technical Monitor)</p> <p>2002-01-01</p> <p>Over the past few years, we have been running SOHO (<span class="hlt">Solar</span> and Heliospheric Observatory)-Sun-Ulysses quadrature campaigns, aimed at comparing the plasma properties at coronal altitudes with plasma properties at interplanetary distances. Coronal plasma has been observed by SOHO experiments: mainly, we used LASCO (Large Angle and Spectrometric Coronagraph Experiment) data to understand the overall coronal configuration at the time of quadratures and analyzed SUMER (<span class="hlt">Solar</span> Ultraviolet Measurements of Emitted Radiation), CDS (Coronal Diagnostic Spectrometer) and UVCS (Ultraviolet Coronagraph Spectrometer) data to derive its physical characteristics. At interplanetary distances, SWICS (<span class="hlt">Solar</span> <span class="hlt">Wind</span> Ion Composition Spectrometer) and SWOOPS (<span class="hlt">Solar</span> <span class="hlt">Wind</span> Observation over the Poles of the Sun) aboard Ulysses provided us with interplanetary plasma data. Here we report on results from some of the campaigns. We notice that, depending on the geometry of the quadrature, i.e. on whether the radial to Ulysses traverses the corona at high or low latitudes, we are able to study different kinds of <span class="hlt">solar</span> <span class="hlt">wind</span>. In particular, a comparison between low-latitude and high-latitude <span class="hlt">wind</span>, allowed us to provide evidence for differences in the acceleration of polar, fast plasma and equatorial, slow plasma: the latter occurring at higher levels and through a more extended region than fast <span class="hlt">wind</span>. These properties are shared by both the proton and heavy ions outflows. Quadrature observations may provide useful information also on coronal vs. in situ elemental composition. To this end, we analyzed spectra taken in the corona, at altitudes ranging between approx. 1.02 and 2.2 <span class="hlt">solar</span> radii, and derived the abundances of a number of ions, including oxygen and iron. Values of the O/Fe ratio, at coronal levels, have been compared with measurements of this ratio made by SWICS at interplanetary distances. Our results are compared with previous findings and predictions from modeling efforts.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1211591','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1211591"><span id="translatedtitle"><span class="hlt">Solar</span> and <span class="hlt">solar-wind</span> composition results from the genesis mission</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wiens, Roger C.; Burnett, D. S.; Hohenberg, C. M.; Meshik, A.; Heber, V.; Grimberg, A.; Wieler, R.; Reisenfeld, D. B.</p> <p>2007-02-20</p> <p>The Genesis mission returned samples of <span class="hlt">solar</span> <span class="hlt">wind</span> to Earth in September, 2004 for ground-based analyses of <span class="hlt">solar-wind</span> composition, particularly for isotope ratios. Substrates, consisting mostly of high-purity semiconductor materials, were exposed to the <span class="hlt">solar</span> <span class="hlt">wind</span> at L1 from December 2001 to April 2004. In addition to a bulk sample of the <span class="hlt">solar</span> <span class="hlt">wind</span>, separate samples of coronal hole, interstream, and coronal mass ejection material were obtained. While many of the substrates were broken upon landing due to the failure to deploy the parachute, a number of results have been obtained, and most of the primary science objectives will likely be met. These include noble gas (He, Ne, Ar, Kr, and Xe) isotope ratios in the bulk <span class="hlt">solar</span> <span class="hlt">wind</span> and in different solarwind regimes, and the nitrogen and oxygen isotope ( <sup>18</sup>O/<sup>17</sup>O/<sup>16</sup>O) ratios to high precision. The greatest successes to date have been with the noble gases. Light noble gases from bulk <span class="hlt">solar</span> <span class="hlt">wind</span> and separate <span class="hlt">solar-wind</span> regime samples have been analyzed to date. The regime compositions are so far ambiguous on the occurrence of the type of isotopic fractionation expected from Coulomb drag acceleration. Neon results from closed system stepped etching of bulk metallic glass have revealed the nature of isotopic fractionation as a function of depth, which in lunar samples have for years deceptively suggested the presence of a separate <span class="hlt">solar</span> component. Isotope ratios of the heavy noble gases, nitrogen, and oxygen are still in the process of being measured.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://web.ift.uib.no/Romfysikk/RESEARCH/PAPERS/huttunen08.pdf','EPRINT'); return false;" href="http://web.ift.uib.no/Romfysikk/RESEARCH/PAPERS/huttunen08.pdf"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> drivers of large geomagnetically induced currents during the <span class="hlt">solar</span> cycle 23</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Bergen, Universitetet i</p> <p></p> <p>amplitudes. The best correlation with the GIC amplitudes was found with the <span class="hlt">solar</span> <span class="hlt">wind</span> electric field geomagnetically induced currents during the <span class="hlt">solar</span> cycle 23, Space Weather, 6, S10002, doi:10.1029/2007SW000374. 1) in tech- nological conductor systems such as power grids or pipelines [e.g., Boteler, 2003; Pirjola, 2000</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22364040','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22364040"><span id="translatedtitle">IMPLICATIONS OF THE RECENT LOW <span class="hlt">SOLAR</span> MINIMUM FOR THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> DURING THE MAUNDER MINIMUM</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lockwood, M.; Owens, M. J.</p> <p>2014-01-20</p> <p>The behavior of the Sun and near-Earth space during grand <span class="hlt">solar</span> minima is not understood; however, the recent long and low minimum of the decadal-scale <span class="hlt">solar</span> cycle gives some important clues, with implications for understanding the <span class="hlt">solar</span> dynamo and predicting space weather conditions. The speed of the near-Earth <span class="hlt">solar</span> <span class="hlt">wind</span> and the strength of the interplanetary magnetic field (IMF) embedded within it can be reliably reconstructed for before the advent of spacecraft monitoring using observations of geomagnetic activity that extend back to the mid-19th century. We show that during the <span class="hlt">solar</span> cycle minima around 1879 and 1901 the average <span class="hlt">solar</span> <span class="hlt">wind</span> speed was exceptionally low, implying the Earth remained within the streamer belt of slow <span class="hlt">solar</span> <span class="hlt">wind</span> flow for extended periods. This is consistent with a broader streamer belt, which was also a feature of the recent low minimum (2009), and yields a prediction that the low near-Earth IMF during the Maunder minimum (1640-1700), as derived from models and deduced from cosmogenic isotopes, was accompanied by a persistent and relatively constant <span class="hlt">solar</span> <span class="hlt">wind</span> of speed roughly half the average for the modern era.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/jdr_tilt/jdr_tilt.withthumbs.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/jdr_tilt/jdr_tilt.withthumbs.pdf"><span id="translatedtitle">The Eect of the Tilt of the HCS on the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Speed in the Outer Heliosphere</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p>1 The Eect of the Tilt of the HCS on the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Speed in the Outer Heliosphere J. D. Richardson: THE HCS TILT AND THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> SPEED #12;2 Abstract. The ow of <span class="hlt">solar</span> <span class="hlt">wind</span> from the Sun is bimodal. High with the HCS tilt controls the <span class="hlt">solar</span> <span class="hlt">wind</span> velocities in the outer heliosphere near <span class="hlt">solar</span> minimum when the Sun</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2007_wpa_99.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2007_wpa_99.pdf"><span id="translatedtitle">VENUS EXPRESS STUDIES PERTAINING TO THE LOSS OF THE VENUS ATMOSPHERE BY ITS INTERACTION WITH THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>WITH THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> C. T. Russell, T. L. Zhang, M. Delva, S. Barabash, J. G. Luhmann, and H. Y. Wei The <span class="hlt">solar</span> effectively excludes the <span class="hlt">solar</span> <span class="hlt">wind</span> from the planetary atmosphere but that the <span class="hlt">solar</span> <span class="hlt">wind</span> can still erode is consistent with the deflection of the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma by the magnetic barrier that in turn shields</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/971292','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/971292"><span id="translatedtitle">The genesis <span class="hlt">solar-wind</span> sample return mission</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wiens, Roger C</p> <p>2009-01-01</p> <p>The compositions of the Earth's crust and mantle, and those of the Moon and Mars, are relatively well known both isotopically and elementally. The same is true of our knowledge of the asteroid belt composition, based on meteorite analyses. Remote measurements of Venus, the Jovian atmosphere, and the outer planet moons, have provided some estimates of their compositions. The Sun constitutes a large majority, > 99%, of all the matter in the <span class="hlt">solar</span> system. The elemental composition of the photosphere, the visible 'surface' of the Sun, is constrained by absorption lines produced by particles above the surface. Abundances for many elements are reported to the {+-}10 or 20% accuracy level. However, the abundances of other important elements, such as neon, cannot be determined in this way due to a relative lack of atomic states at low excitation energies. Additionally and most importantly, the isotopic composition of the Sun cannot be determined astronomically except for a few species which form molecules above sunspots, and estimates derived from these sources lack the accuracy desired for comparison with meteoritic and planetary surface samples measured on the Earth. The <span class="hlt">solar</span> <span class="hlt">wind</span> spreads a sample of <span class="hlt">solar</span> particles throughout the heliosphere, though the sample is very rarified: collecting a nanogram of oxygen, the third most abundant element, in a square centimeter cross section at the Earth's distance from the Sun takes five years. Nevertheless, foil collectors exposed to the <span class="hlt">solar</span> <span class="hlt">wind</span> for periods of hours on the surface of the Moon during the Apollo missions were used to determine the helium and neon <span class="hlt">solar-wind</span> compositions sufficiently to show that the Earth's atmospheric neon was significantly evolved relative to the Sun. Spacecraft instruments developed subsequently have provided many insights into the composition of the <span class="hlt">solar</span> <span class="hlt">wind</span>, mostly in terms of elemental composition. These instruments have the advantage of observing a number of parameters simultaneously, including charge state distributions, velocities, and densities, all of which have been instrumental in characterizing the nature of the <span class="hlt">solar</span> <span class="hlt">wind</span>. However, these instruments have lacked the ability to make large dynamic range measurements of adjacent isotopes (i.e., {sup 17}O/{sup 16}O {approx} 2500) or provide the permil (tenths of percent) accuracy desirable for comparison with geochemical isotopic measurements. An accurate knowledge of the <span class="hlt">solar</span> and <span class="hlt">solar-wind</span> compositions helps to answer important questions across a number of disciplines. It aids in understanding the acceleration mechanisms of the <span class="hlt">solar</span> <span class="hlt">wind</span>, gives an improved picture of the charged particle environment near the photosphere, it constrains processes within the Sun over its history, and it provides a database by which to compare differences among planetary systems with the <span class="hlt">solar</span> system's starting composition, providing key information on planetary evolution. For example, precise knowledge of <span class="hlt">solar</span> isotopic and elemental compositions of volatile species in the Sun provides a baseline for models of atmospheric evolution over time for Earth, Venus, and Mars. Additionally, volatile and chemically active elements such as C, H, O, N, and S can tell us about processes active during the evolution of the <span class="hlt">solar</span> nebula. A classic example of this is the oxygen isotope system. In the 1970s it was determined that the oxygen isotopic ratio in refractory inclusions in primitive meteorites was enriched {approx}4% in {sup 16}O relative to the average terrestrial, lunar, and thermally processed meteorite materials. In addition, all processed <span class="hlt">solar</span>-system materials appeared to each have a unique oxygen isotopic composition (except the Moon and Earth, which are thought to be formed from the same materials), though differences are in the fraction of a percent range, much smaller than the refractory material {sup 16}O enrichment. Several theories were developed over the years to account for the oxygen isotope heterogeneity, each theory predicting a different <span class="hlt">solar</span> isotopic composition and each invoking a differ</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6600840','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6600840"><span id="translatedtitle">Assessment of existing studies of <span class="hlt">wind</span> loading on <span class="hlt">solar</span> collectors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Murphy, L. M.</p> <p>1981-02-01</p> <p>In developing <span class="hlt">solar</span> collectors, <span class="hlt">wind</span> loading is the major structural design consideration. <span class="hlt">Wind</span> loading investigations have focused on establishing safe bounds for steady state loading and verifying rational but initial and conservative design approaches for the various <span class="hlt">solar</span> collector concepts. As such, the effort has been very successful, and has contributed greatly to both the recognition and qualitative understanding of many of the physical phenomena involved. Loading coefficients corresponding to mean <span class="hlt">wind</span> velocities have been derived in these prior studies to measure the expected structural loading on the various <span class="hlt">solar</span> collectors. Current design and testing procedures for <span class="hlt">wind</span> loading are discussed. The test results corresponding to numerous <span class="hlt">wind</span> tests on heliostats, parabolic troughs, parabolic dishes, and field mounted photovoltaic arrays are discussed and the applicability of the findings across the various technologies is assessed. One of the most significant consistencies in the data from all the technologies is the apparent benefit provided by fences and field shielding. Taken in toto, these data show that load reductions of three or possibly more seem feasible, though a more thorough understanding of the phenomena involved must be attained before this benefit can be realized. It is recommended that the required understanding be developed to take advantage of this benefit and that field tests be conducted to correlate with both analyses and tests.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/282791','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/282791"><span id="translatedtitle">Physical nature of the low-speed <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gosling, J.T.</p> <p>1996-09-01</p> <p>In situ observations indicate that the low-speed <span class="hlt">wind</span> is highly variable. It commonly originates on open field lines that thread coronal streamers in the vicinity of the magnetic equator, but transient ejections are also a source of low-speed flows on occasion. Close to the Sun a large flow shear probably is common at the interface between low- and high-speed flows. Near <span class="hlt">solar</span> activity minimum low-speed flows are confined to a narrow band 40-45{degree} wide centered roughly on the <span class="hlt">solar</span> equator, but near <span class="hlt">solar</span> maximum low-speed flows may dominate at all heliographic latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ee.columbia.edu/~lavaei/Projects/Joseph_Flocco_David_Lath.pdf','EPRINT'); return false;" href="http://www.ee.columbia.edu/~lavaei/Projects/Joseph_Flocco_David_Lath.pdf"><span id="translatedtitle">Hydro, <span class="hlt">Solar</span>, <span class="hlt">Wind</span> The Future of Renewable Energy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lavaei, Javad</p> <p></p> <p>Hydro, <span class="hlt">Solar</span>, <span class="hlt">Wind</span> The Future of Renewable Energy Joseph Flocco David Lath Department of Electrical advances have led to a tremendous increase in energy demand all around the world. Countries that previously. Hydropower Water has grown in previous years to become the most widely used form of renewable energy across</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19790052174&hterms=lemon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dlemon','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19790052174&hterms=lemon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dlemon"><span id="translatedtitle">The source of electrostatic fluctuations in the <span class="hlt">solar-wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lemons, D. S.; Asbridge, J. R.; Bame, S. J.; Feldman, W. C.; Gary, S. P.; Gosling, J. T.</p> <p>1979-01-01</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> electron and ion distribution functions measured simultaneously with or close to times of intense electrostatic fluctuations are subjected to a linear Vlasov stability analysis. Although all distributions tested were found to be stable, the analysis suggests that the ion beam instability is the most likely source of the fluctuations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/19238948','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/19238948"><span id="translatedtitle">Air emissions due to <span class="hlt">wind</span> and <span class="hlt">solar</span> power.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Katzenstein, Warren; Apt, Jay</p> <p>2009-01-15</p> <p>Renewables portfolio standards (RPS) encourage large-scale deployment of <span class="hlt">wind</span> and <span class="hlt">solar</span> electric power. Their power output varies rapidly, even when several sites are added together. In many locations, natural gas generators are the lowest cost resource available to compensate for this variability, and must ramp up and down quickly to keep the grid stable, affecting their emissions of NOx and CO2. We model a <span class="hlt">wind</span> or <span class="hlt">solar</span> photovoltaic plus gas system using measured 1-min time-resolved emissions and heat rate data from two types of natural gas generators, and power data from four <span class="hlt">wind</span> plants and one <span class="hlt">solar</span> plant. Over a wide range of renewable penetration, we find CO2 emissions achieve approximately 80% of the emissions reductions expected if the power fluctuations caused no additional emissions. Using steam injection, gas generators achieve only 30-50% of expected NOx emissions reductions, and with dry control NOx emissions increase substantially. We quantify the interaction between state RPSs and NOx constraints, finding that states with substantial RPSs could see significant upward pressure on NOx permit prices, if the gas turbines we modeled are representative of the plants used to mitigate <span class="hlt">wind</span> and <span class="hlt">solar</span> power variability. PMID:19238948</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/~matt/ESSE2006/esse06.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/~matt/ESSE2006/esse06.pdf"><span id="translatedtitle">Dayside Aurora as an Indicator of Asymmetric <span class="hlt">Solar</span> <span class="hlt">Wind</span>-</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Fillingim, Matthew</p> <p></p> <p>Dayside Aurora as an Indicator of Asymmetric <span class="hlt">Solar</span> <span class="hlt">Wind</span>- Magnetosphere Energy Transfer M. O the case of upward currents) aurora respond to these changes Dayside aurora is a direct indicator of how et al. [2005] presented the first simultaneous images of dayside aurora from two global auroral</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1713062B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1713062B"><span id="translatedtitle">The <span class="hlt">Solar-Wind</span> Interaction with Comet Churyumov-Gerasimenko</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burch, James</p> <p>2015-04-01</p> <p>The instruments of the Rosetta Plasma Consortium are providing close-up views of the <span class="hlt">solar-wind</span> interaction with a comet from its dormancy into a period of significant coma development. Although a bow shock has not yet developed, the interactions so far involve significant deflection of the <span class="hlt">solar</span> <span class="hlt">wind</span>; pickup of cometary ions, charge exchange of <span class="hlt">solar-wind</span> ions by the coma resulting in He+ and H- ions being entrained in the <span class="hlt">solar</span> <span class="hlt">wind</span>; the generation of low-frequency 10 - 100 mHz magnetic waves near the comet; electric-fields and waves in the range from DC up to 3.5 MHz, and significant plasma density enhancements, particularly over the neck of the comet. Also observed are negatively-charged nanograins with energies exceeding 20 keV and monoenergetic electron beams (up to 400 eV) indicative of negative charging of shaded regions of the nucleus. As the comet moves closer to the Sun these effects should increase along with the appearance of other expected effects such as a diamagnetic cavity, ionopause, and bow shock along with possibly other new and unexpected plasma and field phenomena.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015LPICo1856.5214Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015LPICo1856.5214Y"><span id="translatedtitle">Microdistribution of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Helium on Itokawa Particle Surfaces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yurimoto, H.; Bajo, K.; Sakaguchi, I.; Suzuki, T. T.; Itose, S.; Matsuya, M.; Ishihara, M.; Uchino, K.</p> <p>2015-07-01</p> <p>We report three-dimensional distribution of <span class="hlt">solar</span> <span class="hlt">wind</span> He irradiated on asteroid Itokawa particles with a voxel resolution of 500×800×3 nm3. The distribution is heterogeneous suggesting escape of He by diffusion and mechanical erosion of particle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015TESS....120001J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015TESS....120001J"><span id="translatedtitle">How Reliable Is the Prediction of <span class="hlt">Solar</span> <span class="hlt">Wind</span> Background?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jian, Lan K.; MacNeice, Peter; Taktakishvili, Aleksandre; Odstrcil, Dusan; Jackson, Bernard; Yu, Hsiu-Shan; Riley, Pete; Sokolov, Igor</p> <p>2015-04-01</p> <p>The prediction of <span class="hlt">solar</span> <span class="hlt">wind</span> background is a necessary part of space weather forecasting. Multiple coronal and heliospheric models have been installed at the Community Coordinated Modeling Center (CCMC) to produce the <span class="hlt">solar</span> <span class="hlt">wind</span>, including the Wang-Sheely-Arge (WSA)-Enlil model, MHD-Around-a-Sphere (MAS)-Enlil model, Space Weather Modeling Framework (SWMF), and heliospheric tomography using interplanetary scintillation (IPS) data. By comparing the modeling results with the OMNI data over 7 Carrington rotations in 2007, we have conducted a third-party validation of these models for the near-Earth <span class="hlt">solar</span> <span class="hlt">wind</span>. This work will help the models get ready for the transition from research to operation. Besides visual comparison, we have quantitatively assessed the models’ capabilities in reproducing the time series and statistics of <span class="hlt">solar</span> <span class="hlt">wind</span> parameters. Using improved algorithms, we have identified magnetic field sector boundaries (SBs) and slow-to-fast stream interaction regions (SIRs) as focused structures. The success rate of capturing them and the time offset vary largely with models. For this period, the 2014 version of MAS-Enlil model works best for SBs, and the heliospheric tomography works best for SIRs. General strengths and weaknesses for each model are identified to provide an unbiased reference to model developers and users.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19840005044&hterms=Planck+Max&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3D%2528Planck%2BMax%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19840005044&hterms=Planck+Max&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3D%2528Planck%2BMax%2529"><span id="translatedtitle">Iron charge states observed in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ipavich, F. M.; Galvin, A. B.; Gloeckler, G.; Hovestadt, D.; Klecker, B.; Scholer, M.</p> <p>1983-01-01</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> measurements from the ULECA sensor of the Max-Planck-Institut/University of Maryland experiment on ISEE-3 are reported. The low energy section of approx the ULECA sensor selects particles by their energy per charge (over the range 3.6 keV/Q to 30 keV/Q) and simultaneously measures their total energy with two low-noise solid state detectors. <span class="hlt">Solar</span> <span class="hlt">wind</span> Fe charge state measurements from three time periods of high speed <span class="hlt">solar</span> <span class="hlt">wind</span> occurring during a post-shock flow and a coronal hole-associated high speed stream are presented. Analysis of the post-shock flow <span class="hlt">solar</span> <span class="hlt">wind</span> indicates the charge state distributions for Fe were peaked at approx +16, indicative of an unusually high coronal temperature (3,000,000 K). In contrast, the Fe charge state distribution observed in a coronal hole-associated high speed stream peaks at approx -9, indicating a much lower coronal temperature (1,400,000 K). This constitutes the first reported measurements of iron charge states in a coronal hole-associated high speed stream.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20120010150&hterms=solar+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2528solar%2Bwind%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20120010150&hterms=solar+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2528solar%2Bwind%2529"><span id="translatedtitle">The <span class="hlt">Solar</span> <span class="hlt">Wind</span> in the Outer Heliosphere and Heliosheath</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, J. D.; Burlaga, L. F.</p> <p>2011-01-01</p> <p>The <span class="hlt">solar</span> <span class="hlt">wind</span> environment has a large influence on the transport of cosmic rays. This chapter discusses the observations of the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and magnetic field in the outer heliosphere and the heliosheath. In the supersonic <span class="hlt">solar</span> <span class="hlt">wind</span>, interaction regions with large magnetic fields form barriers to cosmic ray transport. This effect, the "CR-B" relationship, has been quantified and is shown to be valid everywhere inside the termination shock (TS). In the heliosheath, this relationship breaks down, perhaps because of a change in the nature of the turbulence. Turbulence is compressive in the heliosheath, whereas it was non-compressive in the <span class="hlt">solar</span> <span class="hlt">wind</span>. The plasma pressure in the outer heliosphere is dominated by the pickup ions which gain most of the flow energy at the TS. The heliosheath plasma and magnetic field are highly variable on scales as small as ten minutes. The plasma flow turns away from the nose roughly as predicted, but the radial speeds at Voyager 1 are much less than those at Voyager 2, which is not understood. Despite predictions to the contrary, magnetic reconnection is not an important process in the inner heliosheath with only one observed occurrence to date.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19900047745&hterms=model+driven&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmodel%2Bdriven','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19900047745&hterms=model+driven&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmodel%2Bdriven"><span id="translatedtitle">Investigations of a turbulence-driven <span class="hlt">solar</span> <span class="hlt">wind</span> model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Isenberg, Philip A.</p> <p>1990-01-01</p> <p>This work presents an investigation of the properties of the one-dimensional, two-fluid turbulence-driven <span class="hlt">solar</span> <span class="hlt">wind</span> model introduced by Hollweg and Johnson (1988). It is found that the model has serious difficulties in reproducing the observed high-speed <span class="hlt">wind</span> at 1 AU. In particular, the model proton temperatures are lower than those observed by a factor of 2 or more, and the highest temperature models yield excessive wave intensities at 1 AU. It appears that the problem stems from the specific spatial distribution of heat deposition in the model. Thus this study does not rule out a turbulence-driven fast <span class="hlt">solar</span> <span class="hlt">wind</span>, since other forms of the turbulent evolution could probably achieve better results. A three-fluid version of the model is also presented to show that the addition of alpha particles does not significantly reduce the extreme proton temperatures displayed near the sun by the Hollweg and Johnson work. Finally, it is suggested that the additional heating needs to be located well beyond the critical point, implying that the heating mechanism for the fast <span class="hlt">solar</span> <span class="hlt">wind</span> is likely not the same as that heating the <span class="hlt">solar</span> corona.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19800056266&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bwind%2Benergy','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19800056266&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bwind%2Benergy"><span id="translatedtitle">The <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere energy coupling and magnetospheric disturbances</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Akasofu, S.-I.</p> <p>1980-01-01</p> <p>Energy coupling between the <span class="hlt">solar</span> <span class="hlt">wind</span> and the magnetosphere is examined and the influence of this coupling on magnetospheric disturbances is discussed. Following a review of the components of the total energy production rate of the magnetosphere and progress in the study of <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere correlations, the derivation of the <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere energy coupling function, which has been found to correlate well with the total magnetospheric energy production rate, is presented. Examination of the relations between the energy coupling function and the type of magnetic disturbance with which it is associated indicates that magnetic storms with a large sudden storm commencement and a weak main phase are associated with small energy coupling, while values of the coupling function greater than 5 x 10 to the 18th to 10 to the 19th erg/sec are required for the development of a major geomagnetic storm. The magnetospheric substorm is shown to be a direct result of increased <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere energy coupling rather than the sudden conversion of stored magnetic energy. Finally, it is indicated that at energy couplings greater than 10 to the 19th erg/sec, the positive feedback process responsible for substorms breaks down, resulting in the abnormal growth of the ring current.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=227150','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=227150"><span id="translatedtitle">Livestock water pumping with <span class="hlt">wind</span> and <span class="hlt">solar</span> power</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Recent developments in pumping technologies have allowed for efficient use of renewable energies like <span class="hlt">wind</span> and <span class="hlt">solar</span> to power new pumps for remote water pumping. A helical type, positive displacement pump was developed a few years ago and recently modified to accept input from a variable power sourc...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1218485','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1218485"><span id="translatedtitle">Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study: Executive Summary</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>none,</p> <p>2010-05-01</p> <p>This Study investigates the operational impact of up to 35% energy penetration of <span class="hlt">wind</span>, photovoltaics (PVs), and concentrating <span class="hlt">solar</span> power (CSP) on the power system operated by the WestConnect group of utilities in Arizona, Colorado, Nevada, New Mexico, and Wyoming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19760046362&hterms=solution+plasma+process&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolution%2Bplasma%2Bprocess','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19760046362&hterms=solution+plasma+process&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolution%2Bplasma%2Bprocess"><span id="translatedtitle">Depletion of <span class="hlt">solar</span> <span class="hlt">wind</span> plasma near a planetary boundary</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zwan, B. J.; Wolf, R. A.</p> <p>1976-01-01</p> <p>A mathematical model is presented that describes the squeezing of <span class="hlt">solar</span> <span class="hlt">wind</span> plasma out along interplanetary magnetic field lines in the region between the bow shock and the effective planetary boundary (in the case of the earth, the magnetopause). In the absence of local magnetic merging the squeezing process should create a 'depletion layer', a region of very low plasma density just outside the magnetopause. Numerical solutions are obtained for the dimensionless magnetohydrodynamic equations describing this depletion process for the case where the <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field is perpendicular to the <span class="hlt">solar</span> <span class="hlt">wind</span> flow direction. For the case of the earth, the theory predicts that the density should be reduced by a factor exceeding 2 in a layer about 700-1300 km thick if the Alfven Mach number in the <span class="hlt">solar</span> <span class="hlt">wind</span>, is equal to 8. Scaling of the model calculations to Venus and Mars suggests layer thicknesses about 1/10 and 1/15 those of the earth, respectively, neglecting diffusion and ionospheric effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2011_jgr_A11101.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2011_jgr_A11101.pdf"><span id="translatedtitle">Proton corebeam system in the expanding <span class="hlt">solar</span> <span class="hlt">wind</span>: Hybrid simulations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>Proton corebeam system in the expanding <span class="hlt">solar</span> <span class="hlt">wind</span>: Hybrid simulations Petr Hellinger1,2 and Pavel 9 November 2011. [1] Results of a twodimensional hybrid expanding box simulation of a proton to a decrease of the ratio between the proton perpendicular and parallel temperatures as well as to an increase</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21163473','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21163473"><span id="translatedtitle">A review of <span class="hlt">solar</span> <span class="hlt">wind</span> ion and electron plasma distributions: Present understanding and Ulysses results</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Goldstein, B. E.</p> <p>1996-07-20</p> <p>Unlike the oral version of this paper at <span class="hlt">Solar</span> <span class="hlt">Wind</span> 8, this written version is not intended as an overview of the observational aspects of <span class="hlt">solar</span> <span class="hlt">wind</span> ion and electron distributions, but discusses only recent results in this area with emphasis on Ulysses measurements. Although primarily a review, some new results on <span class="hlt">solar</span> <span class="hlt">wind</span> proton temperatures at high latitudes are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www-ssc.igpp.ucla.edu/personnel/russell/papers/solwind_magsphere_tutorial.pdf','EPRINT'); return false;" href="http://www-ssc.igpp.ucla.edu/personnel/russell/papers/solwind_magsphere_tutorial.pdf"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> and Interplanetary Magnetic Field: A Tutorial C. T. Russell</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Russell, Christopher T.</p> <p></p> <p><span class="hlt">Solar</span> <span class="hlt">Wind</span> and Interplanetary Magnetic Field: A Tutorial C. T. Russell Institute of Geophysics at the center of the sun to its radiation into space by the photosphere, but most importantly for the <span class="hlt">solar</span> <span class="hlt">wind</span> controls the properties of the <span class="hlt">solar</span> <span class="hlt">wind</span>. In this tutorial review we examine the properties of the fields</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/1990_gms_401.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/1990_gms_401.pdf"><span id="translatedtitle">THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> INTERACTION WITH UNMAGNETIZED PLANETS: A TUTORIAL J. G. Luhmann</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> INTERACTION WITH UNMAGNETIZED PLANETS: A TUTORIAL J. G. Luhmann Institute of <span class="hlt">solar</span> <span class="hlt">wind</span> origin is transported through the ionopause and distributed within the ionosphere theorists and observationalists. The relative strength of the <span class="hlt">solar</span> <span class="hlt">wind</span> and ionospheric pressures at Mars</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ee.columbia.edu/~lavaei/Projects/Daniel_Rosenthal.pdf','EPRINT'); return false;" href="http://www.ee.columbia.edu/~lavaei/Projects/Daniel_Rosenthal.pdf"><span id="translatedtitle">Mitigating the effects of intermittency and variability of <span class="hlt">wind</span> and <span class="hlt">solar</span> power</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lavaei, Javad</p> <p></p> <p>Mitigating the effects of intermittency and variability of <span class="hlt">wind</span> and <span class="hlt">solar</span> power Daniel Rosenthal sources. The two sources of interest for this paper are <span class="hlt">solar</span> and <span class="hlt">wind</span> power, which have the potential]. Clearly <span class="hlt">solar</span> energy has the potential to be a major source of our power. Likewise, <span class="hlt">wind</span> energy on earth</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://web.ift.uib.no/~nikost/papers/En_an_2001JA002002.pdf','EPRINT'); return false;" href="http://web.ift.uib.no/~nikost/papers/En_an_2001JA002002.pdf"><span id="translatedtitle">Energy analysis of substorms based on remote sensing techniques, <span class="hlt">solar</span> <span class="hlt">wind</span> measurements, and geomagnetic indices</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Ã?stgaard, Nikolai</p> <p></p> <p>Energy analysis of substorms based on remote sensing techniques, <span class="hlt">solar</span> <span class="hlt">wind</span> measurements to balance the energy budget. We find that a viscous interaction that transfers 0.17% of the <span class="hlt">solar</span> <span class="hlt">wind</span>, is sufficient to balance the total energy dissipation UT. INDEX TERMS: 2784 Magnetospheric Physics: <span class="hlt">Solar</span> <span class="hlt">wind</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/cw_evol/cw_evol.withthumbs.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/cw_evol/cw_evol.withthumbs.pdf"><span id="translatedtitle">A numerical study of the evolution of the <span class="hlt">solar</span> <span class="hlt">wind</span> from Ulysses to Voyager 2</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p>1 A numerical study of the evolution of the <span class="hlt">solar</span> <span class="hlt">wind</span> from Ulysses to Voyager 2 C. Wang and J. D Alamos National Laboratory, Los Alamos Short title: EVOLUTION OF THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> #12;2 Abstract. Voyager 2 continues to explore the outer heliosphere as Ulysses studies the latitudinal dependence of the <span class="hlt">solar</span> <span class="hlt">wind</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2006_aj_704.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2006_aj_704.pdf"><span id="translatedtitle"><span class="hlt">SOLAR</span> <span class="hlt">WIND</span> ELECTRIC FIELDS IN THE ION CYCLOTRON FREQUENCY RANGE P. J. Kellogg,1</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p><span class="hlt">SOLAR</span> <span class="hlt">WIND</span> ELECTRIC FIELDS IN THE ION CYCLOTRON FREQUENCY RANGE P. J. Kellogg,1 S. D. Bale,2 F. S of magnetic moment in the expanding <span class="hlt">solar</span> <span class="hlt">wind</span> to maintain nearly isotropic velocity distributions. Subject headingg: <span class="hlt">solar</span> <span class="hlt">wind</span> 1. INTRODUCTION In earlier papers (Kellogg & Lin 1997; Kellogg 2000; Kellogg et al</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://lasp.colorado.edu/~eriksson/2006JA011863_gosling.pdf','EPRINT'); return false;" href="http://lasp.colorado.edu/~eriksson/2006JA011863_gosling.pdf"><span id="translatedtitle">Petschek-type magnetic reconnection exhausts in the <span class="hlt">solar</span> <span class="hlt">wind</span> well inside 1 AU: Helios</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Eriksson, Stefan</p> <p></p> <p>Petschek-type magnetic reconnection exhausts in the <span class="hlt">solar</span> <span class="hlt">wind</span> well inside 1 AU: Helios J. T; published 5 October 2006. [1] Petschek-type reconnection exhausts can be recognized in <span class="hlt">solar</span> <span class="hlt">wind</span> plasma in the <span class="hlt">solar</span> <span class="hlt">wind</span> inward to heliocentric distances of 0.31 AU. Most of the exhaust jets identified</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dartmouth.edu/~rdenton/swpar.pdf','EPRINT'); return false;" href="http://www.dartmouth.edu/~rdenton/swpar.pdf"><span id="translatedtitle">July 10, 2007, revised manuscript submitted to SW <span class="hlt">Solar</span> <span class="hlt">Wind</span> Parameters for Magnetospheric Magnetic</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lotko, William</p> <p></p> <p>July 10, 2007, revised manuscript submitted to SW <span class="hlt">Solar</span> <span class="hlt">Wind</span> Parameters for Magnetospheric Magnetic require <span class="hlt">solar</span> <span class="hlt">wind</span> and IMF data, which are not always available. Data gaps are especially common for times present a method to interpolate the <span class="hlt">solar</span> <span class="hlt">wind</span> characteristics across data gaps and to evaluate the W</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www-cfadc.phy.ornl.gov/MIRF/SolarWindSputtering/meyer-SW13.pdf','EPRINT'); return false;" href="http://www-cfadc.phy.ornl.gov/MIRF/SolarWindSputtering/meyer-SW13.pdf"><span id="translatedtitle">Kinetic And Potential Sputtering Of Lunar Regolith: The Contribution Of The Heavy (Minority) <span class="hlt">Solar</span> <span class="hlt">Wind</span> Ions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>, Huntsville, AL 35812, USA Abstract. In this paper the sputtering of lunar regolith by protons and <span class="hlt">solar</span> <span class="hlt">wind</span> of JSC-1A AGGL lunar regolith simulant at <span class="hlt">solar</span> <span class="hlt">wind</span> velocities, and TRIM simulations of kinetic to the minority heavy ion multicharged ion <span class="hlt">solar</span> <span class="hlt">wind</span> component, and the kinetic sputtering contribution of all</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sun.stanford.edu/~xuepu/PUBLICATION/bala2004.pdf','EPRINT'); return false;" href="http://sun.stanford.edu/~xuepu/PUBLICATION/bala2004.pdf"><span id="translatedtitle">Discrepancies in the Prediction of <span class="hlt">Solar</span> <span class="hlt">Wind</span> using Potential Field Source Surface Model: An</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Zhao, Xuepu</p> <p></p> <p>Discrepancies in the Prediction of <span class="hlt">Solar</span> <span class="hlt">Wind</span> using Potential Field Source Surface Model between the magnetic flux tube expansion factor (FTE) at the source surface and the <span class="hlt">solar</span> <span class="hlt">wind</span> speed observed at Earth, which has been made use of in the prediction of <span class="hlt">solar</span> <span class="hlt">wind</span> speed near the Earth</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://tswww.ism.ac.jp/higuchi/index_e/papers/JGR_Nakano2009.pdf','EPRINT'); return false;" href="http://tswww.ism.ac.jp/higuchi/index_e/papers/JGR_Nakano2009.pdf"><span id="translatedtitle">Impact of the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure on the Region 2 field-aligned currents</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Higuchi, Tomoyuki</p> <p></p> <p>Impact of the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure on the Region 2 field-aligned currents S. Nakano,1,2 G and the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure is investigated using magnetic field data from Defense Meteorological in the magnetosphere varies with the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure. Therefore, we can expect that the Region 2 currents</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://odin.gi.alaska.edu/lumm/Papers/Boudouridis_2002JA009373.pdf','EPRINT'); return false;" href="http://odin.gi.alaska.edu/lumm/Papers/Boudouridis_2002JA009373.pdf"><span id="translatedtitle">Effect of <span class="hlt">solar</span> <span class="hlt">wind</span> pressure pulses on the size and strength of the auroral oval</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lummerzheim, Dirk</p> <p></p> <p>Effect of <span class="hlt">solar</span> <span class="hlt">wind</span> pressure pulses on the size and strength of the auroral oval A. Boudouridis, E. [1] It has recently been found that <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure changes can dramatically affect <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure increases on the location, size, and intensity of the auroral oval using</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/jdr_lag/jdr_lag.new.withthumbs.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/jdr_lag/jdr_lag.new.withthumbs.pdf"><span id="translatedtitle">The orientation of plasma structure in the <span class="hlt">solar</span> <span class="hlt">wind</span> J. D. Richardson and K. I. Paularena</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p>The orientation of plasma structure in the <span class="hlt">solar</span> <span class="hlt">wind</span> J. D. Richardson and K. I. Paularena Center, and <span class="hlt">WIND</span> spacecraft are used to #12;nd the average east-west orientation of plasma structures in the <span class="hlt">solar</span> correlations between data sets. These lags, when combined with the spacecraft positions and <span class="hlt">solar</span> <span class="hlt">wind</span> speeds</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.prl.res.in/~jerry/PAPERS/Janardhan-etal-jgr-2008.pdf','EPRINT'); return false;" href="http://www.prl.res.in/~jerry/PAPERS/Janardhan-etal-jgr-2008.pdf"><span id="translatedtitle">Source regions of <span class="hlt">solar</span> <span class="hlt">wind</span> disappearance events P. Janardhan,1,3</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Padmanabhan, Janardhan</p> <p></p> <p>Source regions of <span class="hlt">solar</span> <span class="hlt">wind</span> disappearance events P. Janardhan,1,3 K. Fujiki,2 H. S. Sawant,3 M, in May 1999, March 2002, and May 2002, respectively, when the <span class="hlt">solar</span> <span class="hlt">wind</span> densities at 1 AU dropped-density anomalies observed at 1 AU are referred to as ``<span class="hlt">solar</span> <span class="hlt">wind</span> disappearance events'' and in this paper, we</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://lasp.colorado.edu/~lix/paper/JGR/08/Burin-des-Roziers.pdf','EPRINT'); return false;" href="http://lasp.colorado.edu/~lix/paper/JGR/08/Burin-des-Roziers.pdf"><span id="translatedtitle">Energetic plasma sheet electrons and their relationship with the <span class="hlt">solar</span> <span class="hlt">wind</span>: A Cluster and Geotail study</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Li, Xinlin</p> <p></p> <p>Energetic plasma sheet electrons and their relationship with the <span class="hlt">solar</span> <span class="hlt">wind</span>: A Cluster and Geotail and the <span class="hlt">solar</span> <span class="hlt">wind</span>, as well as >2 MeV geosynchronous electrons, is investigated using plasma sheet measurements from Cluster (2001­2005) and Geotail (1998­2005) and concurrent <span class="hlt">solar</span> <span class="hlt">wind</span> measurements from ACE</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://odin.gi.alaska.edu/lumm/Papers/Boudouridis_2008JA013489.pdf','EPRINT'); return false;" href="http://odin.gi.alaska.edu/lumm/Papers/Boudouridis_2008JA013489.pdf"><span id="translatedtitle">Nightside flow enhancement associated with <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure driven reconnection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lummerzheim, Dirk</p> <p></p> <p>Nightside flow enhancement associated with <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure driven reconnection A years the prominent role of <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure in enhancing dayside and nightside reconnection. Super Dual Auroral Radar Network (SuperDARN) observations show that <span class="hlt">solar</span> <span class="hlt">wind</span> pressure fronts induce</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.eiscat.rl.ac.uk/Members/mike/publications/pdfs/2010/263_Rouillard_2009JA014472.pdf','EPRINT'); return false;" href="http://www.eiscat.rl.ac.uk/Members/mike/publications/pdfs/2010/263_Rouillard_2009JA014472.pdf"><span id="translatedtitle">Intermittent release of transients in the slow <span class="hlt">solar</span> <span class="hlt">wind</span>: 2. In situ evidence</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lockwood, Mike</p> <p></p> <p>Click Here for Full Article Intermittent release of transients in the slow <span class="hlt">solar</span> <span class="hlt">wind</span>: 2. In situ, the variability of the slow <span class="hlt">solar</span> <span class="hlt">wind</span> which originates near helmet streamers. The observation of intense intermittent transient outflow by HI implies that the corresponding in situ observations of the slow <span class="hlt">solar</span> <span class="hlt">wind</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('ftp://space.mit.edu/pub/plasma/publications/cw_motion/cw_motion.withthumbs.pdf','EPRINT'); return false;" href="ftp://space.mit.edu/pub/plasma/publications/cw_motion/cw_motion.withthumbs.pdf"><span id="translatedtitle">The heliospheric boundary response to large scale <span class="hlt">solar</span> <span class="hlt">wind</span> uctuations: a gasdynamic model with pickup ions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Richardson, John</p> <p></p> <p>1 The heliospheric boundary response to large scale <span class="hlt">solar</span> <span class="hlt">wind</span> uctuations: a gasdynamic model. Observations show that the <span class="hlt">solar</span> <span class="hlt">wind</span> ram pressure has large-scale uctuations on the time scale of days of the <span class="hlt">solar</span> <span class="hlt">wind</span> with the local interstellar medium, which includes the mutual interaction of the interstellar</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.glue.umd.edu/~sitnov/testpage_files/recpubl/2003GL018932.pdf','EPRINT'); return false;" href="http://www.glue.umd.edu/~sitnov/testpage_files/recpubl/2003GL018932.pdf"><span id="translatedtitle">Global and multi-scale features of <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere coupling: From modeling to forecasting</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Sitnov, Mikhail I.</p> <p></p> <p>Global and multi-scale features of <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere coupling: From modeling to forecasting is a spatially extended nonlinear system driven far from equilibrium by the turbulent <span class="hlt">solar</span> <span class="hlt">wind</span>. During issue. This paper presents a data-derived model of the <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere coupling that combines</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://odin.gi.alaska.edu/lumm/Papers/boudouridis_2004JA010704.pdf','EPRINT'); return false;" href="http://odin.gi.alaska.edu/lumm/Papers/boudouridis_2004JA010704.pdf"><span id="translatedtitle">Enhanced <span class="hlt">solar</span> <span class="hlt">wind</span> geoeffectiveness after a sudden increase in dynamic pressure during southward IMF orientation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lummerzheim, Dirk</p> <p></p> <p>Enhanced <span class="hlt">solar</span> <span class="hlt">wind</span> geoeffectiveness after a sudden increase in dynamic pressure during southward increase in <span class="hlt">solar</span> <span class="hlt">wind</span> pressure results in poleward expansion of the auroral oval and closing of the polar show that southward IMF conditions combined with high <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure immediately after</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://lasp.colorado.edu/~lix/paper/SW/05/edbr_swj2006.pdf','EPRINT'); return false;" href="http://lasp.colorado.edu/~lix/paper/SW/05/edbr_swj2006.pdf"><span id="translatedtitle">Specification of >2 MeV geosynchronous electrons based on <span class="hlt">solar</span> <span class="hlt">wind</span> measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Li, Xinlin</p> <p></p> <p>Specification of >2 MeV geosynchronous electrons based on <span class="hlt">solar</span> <span class="hlt">wind</span> measurements E. Burin des affected by the <span class="hlt">solar</span> <span class="hlt">wind</span>. Statistical asynchronous regression (SAR), a statistical method recently use measurements directly from the <span class="hlt">solar</span> <span class="hlt">wind</span>, instead of the Kp index, and the SAR method</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://astronauticsnow.com/mg_pubs/gruntman_jgr_2006.pdf','EPRINT'); return false;" href="http://astronauticsnow.com/mg_pubs/gruntman_jgr_2006.pdf"><span id="translatedtitle">Imaging the global <span class="hlt">solar</span> <span class="hlt">wind</span> flow in EUV Mike Gruntman,1</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Gruntman, Mike</p> <p></p> <p>Imaging the global <span class="hlt">solar</span> <span class="hlt">wind</span> flow in EUV Mike Gruntman,1 Vlad Izmodenov,2,3 and Vic Pizzo4] We advance the original concept of imaging the three-dimensional <span class="hlt">solar</span> <span class="hlt">wind</span> flow (Gruntman, 2001a) by characterizing expected heliospheric EUV signatures under assumptions of a realistic <span class="hlt">solar</span> <span class="hlt">wind</span>. Charge exchange</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.astropa.unipa.it/Library/OAPA_preprints/wave.ps.gz','EPRINT'); return false;" href="http://www.astropa.unipa.it/Library/OAPA_preprints/wave.ps.gz"><span id="translatedtitle">Propagation of three--dimensional Alfv'en waves in a stratified, thermally conducting <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>term). Our magnetohydrodynamic <span class="hlt">solar</span> <span class="hlt">wind</span> model also accounts for the momentum deposition by a spectrumPropagation of three--dimensional Alfv'en waves in a stratified, thermally conducting <span class="hlt">solar</span> <span class="hlt">wind</span> S Alfv'en waves in the <span class="hlt">solar</span> atmosphere and <span class="hlt">wind</span>, taking into account relevant physical effects</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://lasp.colorado.edu/~lix/paper/JGR/07/2006JA011918.pdf','EPRINT'); return false;" href="http://lasp.colorado.edu/~lix/paper/JGR/07/2006JA011918.pdf"><span id="translatedtitle">Prediction of the AL index using <span class="hlt">solar</span> <span class="hlt">wind</span> Xinlin Li,1,2,5</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Li, Xinlin</p> <p></p> <p>magnetic field and velocity but is practically independent of the <span class="hlt">solar</span> <span class="hlt">wind</span> density. Citation: Li, X., KPrediction of the AL index using <span class="hlt">solar</span> <span class="hlt">wind</span> parameters Xinlin Li,1,2,5 Kap Soo Oh,1,3 and M. S. Oh, and M. Temerin (2007), Prediction of the AL index using <span class="hlt">solar</span> <span class="hlt">wind</span> parameters, J. Geophys</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.prl.res.in/~jerry/PAPERS/JAA_V27-2006.pdf','EPRINT'); return false;" href="http://www.prl.res.in/~jerry/PAPERS/JAA_V27-2006.pdf"><span id="translatedtitle">J. Astrophys. Astr. (2006) 27, 17 Enigmatic <span class="hlt">Solar</span> <span class="hlt">Wind</span> Disappearance Events Do We Understand</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Padmanabhan, Janardhan</p> <p>2006-01-01</p> <p>J. Astrophys. Astr. (2006) 27, 1­7 Enigmatic <span class="hlt">Solar</span> <span class="hlt">Wind</span> Disappearance Events ­ Do We Understand@prl.ernet.in Abstract. At the Sun­Earth distance of one astronomical unit (1 AU), the <span class="hlt">solar</span> <span class="hlt">wind</span> is known to be strongly, <span class="hlt">solar</span> <span class="hlt">wind</span> densities (average 10 cm-3 ) and velocities (average 450 km s-1 ) at 1 AU, are known</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2010_tisw_296.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2010_tisw_296.pdf"><span id="translatedtitle">Langmuir wave-packet generation from an electron beam propagating in the inhomogeneous <span class="hlt">solar</span> <span class="hlt">wind</span>.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>Langmuir wave-packet generation from an electron beam propagating in the inhomogeneous <span class="hlt">solar</span> <span class="hlt">wind</span> of the destabilization of Langmuir waves by a beam propagating in the inhomogeneous <span class="hlt">solar</span> <span class="hlt">wind</span>. The main results in the <span class="hlt">solar</span> <span class="hlt">wind</span> [2], and that the propagation of Langmuir Waves is affected by such fluctuations : in par</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.nanoscience.gatech.edu/paper/2014/14_NR_05.pdf','EPRINT'); return false;" href="http://www.nanoscience.gatech.edu/paper/2014/14_NR_05.pdf"><span id="translatedtitle">Hybrid energy cell for simultaneously harvesting <span class="hlt">wind</span>, <span class="hlt">solar</span>, and chemical energies</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Wang, Zhong L.</p> <p></p> <p>Hybrid energy cell for simultaneously harvesting <span class="hlt">wind</span>, <span class="hlt">solar</span>, and chemical energies Yingchun Wu1 KEYWORDS hybrid energy cell, <span class="hlt">wind</span> energy, <span class="hlt">solar</span> energy, triboelectric nanogenerators, electrochemical cells ABSTRACT We report a hybrid energy cell that can simultaneously or individually harvest <span class="hlt">wind</span>, <span class="hlt">solar</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2006_grl_L08106.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2006_grl_L08106.pdf"><span id="translatedtitle">On the occurrence of magnetic enhancements caused by <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with lunar crustal fields</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>interaction between <span class="hlt">solar</span> <span class="hlt">wind</span> particles and fields and the Moon has been studied in depth. As discussedOn the occurrence of magnetic enhancements caused by <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with lunar crustal disturbances convecting downstream with the <span class="hlt">solar</span> <span class="hlt">wind</span>, and implies that crustal fields are sometimes strong</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.resnick.caltech.edu/docs/sg_vittal.pdf','EPRINT'); return false;" href="http://www.resnick.caltech.edu/docs/sg_vittal.pdf"><span id="translatedtitle">Impact of increased penetration of <span class="hlt">wind</span> and PV <span class="hlt">solar</span> resources on the</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Stoltz, Brian M.</p> <p></p> <p>;<span class="hlt">Wind</span> and PV <span class="hlt">solar</span> grid interface · Modern <span class="hlt">wind</span> turbine generators are typically rated between 1.5 MW turbine generator Schematic of Type 4 <span class="hlt">wind</span> turbine generator #12;<span class="hlt">Wind</span> and PV <span class="hlt">solar</span> grid interface · Large of them will decrease · The synchronizing capability between those generators whose rotor angle difference</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22036908','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22036908"><span id="translatedtitle">THREE-DIMENSIONAL EVOLUTION OF <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> DURING <span class="hlt">SOLAR</span> CYCLES 22-24</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Manoharan, P. K.</p> <p>2012-06-01</p> <p>This paper presents an analysis of three-dimensional evolution of <span class="hlt">solar</span> <span class="hlt">wind</span> density turbulence and speed at various levels of <span class="hlt">solar</span> activity between <span class="hlt">solar</span> cycles 22 and 24. The <span class="hlt">solar</span> <span class="hlt">wind</span> data used in this study have been obtained from the interplanetary scintillation (IPS) measurements made at the Ooty Radio Telescope, operating at 327 MHz. Results show that (1) on average, there was a downward trend in density turbulence from the maximum of cycle 22 to the deep minimum phase of cycle 23; (2) the scattering diameter of the corona around the Sun shrunk steadily toward the Sun, starting from 2003 to the smallest size at the deepest minimum, and it corresponded to a reduction of {approx}50% in the density turbulence between the maximum and minimum phases of cycle 23; (3) the latitudinal distribution of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed was significantly different between the minima of cycles 22 and 23. At the minimum phase of <span class="hlt">solar</span> cycle 22, when the underlying <span class="hlt">solar</span> magnetic field was simple and nearly dipole in nature, the high-speed streams were observed from the poles to {approx}30 Degree-Sign latitudes in both hemispheres. In contrast, in the long-decay phase of cycle 23, the sources of the high-speed <span class="hlt">wind</span> at both poles, in accordance with the weak polar fields, occupied narrow latitude belts from poles to {approx}60 Degree-Sign latitudes. Moreover, in agreement with the large amplitude of the heliospheric current sheet, the low-speed <span class="hlt">wind</span> prevailed in the low- and mid-latitude regions of the heliosphere. (4) At the transition phase between cycles 23 and 24, the high levels of density and density turbulence were observed close to the heliospheric equator and the low-speed <span class="hlt">solar</span> <span class="hlt">wind</span> extended from the equatorial-to-mid-latitude regions. The above results in comparison with Ulysses and other in situ measurements suggest that the source of the <span class="hlt">solar</span> <span class="hlt">wind</span> has changed globally, with the important implication that the supply of mass and energy from the Sun to the interplanetary space has been significantly reduced in the prolonged period of low <span class="hlt">solar</span> activity. The IPS results are consistent with the onset and growth of the current <span class="hlt">solar</span> cycle 24, starting from the middle of 2009. However, the width of the high-speed <span class="hlt">wind</span> at the northern high latitudes has almost disappeared and indicates that the ascending phase of the current cycle has almost reached the maximum phase in the northern hemisphere of the Sun. However, in the southern part of the hemisphere, the <span class="hlt">solar</span> activity has yet to develop and/or increase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19910041672&hterms=Krypton&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DKrypton','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19910041672&hterms=Krypton&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DKrypton"><span id="translatedtitle"><span class="hlt">Solar-wind</span> krypton and solid/gas fractionation in the early <span class="hlt">solar</span> nebula</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wiens, Roger C.; Burnett, D. S.; Neugebauer, M.; Pepin, R. O.</p> <p>1991-01-01</p> <p>The <span class="hlt">solar</span>-system Kr abundance is calculated from <span class="hlt">solar-wind</span> noble-gas ratios, determined previously by low-temperature oxidations of lunar ilmenite grains, normalized to Si by spacecraft <span class="hlt">solar-wind</span> measurements. The estimated Kr-83 abundance of 4.1 + or - 1.5 per million Si atoms is within uncertainty of estimates assuming no fractionation, determined from CI-chondrite abundances of surrounding elements. This is significant because it is the first such constraint on solid/gas fractionation, though the large uncertainty only confines it to somewhat less than a factor of two.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15834110','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15834110"><span id="translatedtitle">Season- and <span class="hlt">latitude-dependent</span> effects of simulated twilights on circadian entrainment.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Boulos, Ziad; Macchi, M Mila</p> <p>2005-04-01</p> <p>Groups of Syrian hamsters were exposed to LD cycles with twilight transitions and photoperiods simulating natural lighting conditions at the summer solstice (SS), equinox, and winter solstice (WS) at 41 degrees N and at the winter solstice at the Arctic Circle (WS 66 degrees N) but with daytime illuminance truncated at 10 lux (LD-twilight). Separate groups were kept under matching rectangular cycles (LD-rectangular). The inclusion of twilights affected several circadian parameters in a season-and <span class="hlt">latitude-dependent</span> manner. The most striking difference was in the timing of activity onsets, which followed dusk in the presence of twilights but were more closely related to dawn (lights-on) in their absence. Activity offsets and midpoints were also earlier in LD-twilight than in LD-rectangular, with the differences being most pronounced under WS 66 degrees N. In LD-twilight, longer nights resulted in earlier offsets and midpoints, but in LD-rectangular, midpoints were later under long than under short nights while offsets did not vary significantly. In LD-twilight, activity duration (alpha) increased monotonically with increasing nighttime duration, but in LD-rectangular, alpha was shorter under WS 66 degrees N than under WS conditions. These effects of season and latitude observed in LD-twilight were similar to those reported in animals exposed to natural illumination, while those observed in LD-rectangular differed in several respects. The presence of twilights also resulted in lower day-to-day variability in activity onset times (greater precision), supporting the earlier conclusion that twilights increase the strength of the LD zeitgeber. Free-running periods in constant darkness (DD) were shorter in LD-twilight than in LD-rectangular, especially under WS 66 degrees N, raising the possibility that the effects of twilights on the timing of the entrained activity rhythm reflect their effects on the period of that rhythm. Increasing daytime illuminance to 100 lux (WS conditions only) resulted in earlier activity offsets and midpoints and a shorter alpha but had no effect on activity onsets or on subsequent period in DD. These results indicate that exposure to low twilight illuminances alone can account for several of the documented differences between the effects of natural and rectangular light cycles on circadian entrainment. PMID:15834110</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/977319','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/977319"><span id="translatedtitle">Large Scale <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration in Germany</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ernst, Bernhard; Schreirer, Uwe; Berster, Frank; Pease, John; Scholz, Cristian; Erbring, Hans-Peter; Schlunke, Stephan; Makarov, Yuri V.</p> <p>2010-02-28</p> <p>This report provides key information concerning the German experience with integrating of 25 gigawatts of <span class="hlt">wind</span> and 7 gigawatts of <span class="hlt">solar</span> power capacity and mitigating its impacts on the electric power system. The report has been prepared based on information provided by the Amprion GmbH and 50Hertz Transmission GmbH managers and engineers to the Bonneville Power Administration (BPA) and Pacific Northwest National Laboratory representatives during their visit to Germany in October 2009. The trip and this report have been sponsored by the BPA Technology Innovation office. Learning from the German experience could help the Bonneville Power Administration engineers to compare and evaluate potential new solutions for managing higher penetrations of <span class="hlt">wind</span> energy resources in their control area. A broader dissemination of this experience will benefit <span class="hlt">wind</span> and <span class="hlt">solar</span> resource integration efforts in the United States.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19830064808&hterms=lower+hybrid+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dlower%2Bhybrid%2Bwaves','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19830064808&hterms=lower+hybrid+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dlower%2Bhybrid%2Bwaves"><span id="translatedtitle">Electromagnetic lower hybrid waves in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Marsch, E.; Chang, T.</p> <p>1983-01-01</p> <p>An analysis of electromagnetic lower hybrid waves or hybrid whistlers that propagate nearly perpendicular to the magnetic field lines in the <span class="hlt">solar</span> <span class="hlt">wind</span> is described. Doppler-shifted, these waves have a broadband nature when observed in the spacecraft frame depending on the direction of propagation and the supersonic flow velocity of the <span class="hlt">wind</span>. Lower hybrid waves can energize ions normal to the interplanetary magnetic field. They may occasionaly be responsible for the observed temperature anisotropy in high speed streams and possibly for the acceleration of heavier ions such as the oxygen ions, alpha particles, etc. These modes are probably driven unstable by the anisotropic halos of the <span class="hlt">solar</span> <span class="hlt">wind</span> electron distributions exhibiting 'heat flux' profiles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/astro-ph/0404580v1','EPRINT'); return false;" href="http://arxiv.org/pdf/astro-ph/0404580v1"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> induced magnetic field around the unmagnetized Earth</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>G. T. Birk; H. Lesch; C. Konz</p> <p>2004-04-29</p> <p>The Earth is a planet with a dipolar magnetic field which is agitated by a magnetized plasma <span class="hlt">wind</span> streaming from the Sun. The magnetic field shields the Earth's surface from penetrating high energy <span class="hlt">solar</span> <span class="hlt">wind</span> particles, as well as interstellar cosmic rays. The magnetic dipole has reversed sign some hundreds of times over the last 400 million years. These polarity reversals correspond to drastic breakdowns of the dynamo action. The question arises what the consequences for the Earth's atmosphere, climate, and, in particular, biosphere are. It is shown by kinematic estimates and three-dimensional plasma-neutral gas simulations that the <span class="hlt">solar</span> <span class="hlt">wind</span> can induce very fast a magnetic field in the previously completely unmagnetized Earth's ionosphere that is strong enough to protect Earth from cosmic radiations comparable to the case of an intact magnetic dynamo.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19730002050&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsolar%2Bwind%2Benergy','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19730002050&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsolar%2Bwind%2Benergy"><span id="translatedtitle">Model for energy transfer in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Model results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barnes, A. A., Jr.; Hartle, R. E.</p> <p>1972-01-01</p> <p>A description is given of the results of <span class="hlt">solar</span> <span class="hlt">wind</span> flow in which the heating is due to (1) propagation and dissipation of hydromagnetic waves generated near the base of the <span class="hlt">wind</span>, and (2) thermal conduction. A series of models is generated for fixed values of density, electron and proton temperature, and magnetic field at the base by varying the wave intensity at the base of the model. This series of models predicts the observed correlation between flow speed and proton temperature for a large range of velocities. The wave heating takes place in a shell about the sun greater than or approximately equal to 10 R thick. We conclude that large-scale variations observed in the <span class="hlt">solar</span> <span class="hlt">wind</span> are probably due mainly to variation in the hydromagnetic wave flux near the sun.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021407&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dsolar%2Bwaves','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021407&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dsolar%2Bwaves"><span id="translatedtitle">High amplitude waves in the expanding <span class="hlt">solar</span> <span class="hlt">wind</span> plasma</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schmidt, J. M.; Velli, M.; Grappin, R.</p> <p>1995-01-01</p> <p>We simulated the 1-D nonlinear time-evolution of high-amplitude Alfven, slow and fast magnetoacoustic waves in the <span class="hlt">solar</span> <span class="hlt">wind</span> propagating outward at different angles to the mean magnetic (spiral) field, using the expanding box model. The simulation results for Alfven waves and fast magnetoacustic waves fit the observational constraints in the <span class="hlt">solar</span> <span class="hlt">wind</span> best, showing decreasing trends for energies and other rms-quantities due to expansion and the appearance of inward propagating waves as minor species in the <span class="hlt">wind</span>. Inward propagating waves are generated by reflection of Alfven waves propagating at large angles to the magnetic field or they coincide with the occurrence of compressible fluctuations. In our simulations, fast and slow magnetoacoustic waves seem to have a level in the density-fluctuations which is too high when we compare with the observations. Furthermore, the evolution of energies for slow magnetoacoustic waves differs strongly from the evolution of fluctuation energies in situ.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1104.1440.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1104.1440.pdf"><span id="translatedtitle">The interaction between the Moon and the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Holmström, M; Futaana, Y; Nilsson, H</p> <p>2011-01-01</p> <p>We study the interaction between the Moon and the <span class="hlt">solar</span> <span class="hlt">wind</span> using a three-dimensional hybrid plasma solver. The proton fluxes and electromagnetical fields are presented for typical <span class="hlt">solar</span> <span class="hlt">wind</span> conditions with different magnetic field directions. Several features are consistent with a fluid interaction, e.g., the presence of a rarefaction cone, and an increased magnetic field in the wake. There are however several kinetic features of the interaction. We find kinks in the magnetic field at the wake boundary. There are also density and magnetic field variations in the far wake, maybe from an ion beam instability related to the wake refill. The results are compared to observations by the <span class="hlt">WIND</span> spacecraft during a wake crossing. The model magnetic field and ion velocities are in agreement with the measurements. The density and the electron temperature in the central wake are not as well captured by the model, probably from the lack of electron physics in the hybrid model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19790049170&hterms=nonequilibrium+conditions&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dnonequilibrium%2Bconditions','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19790049170&hterms=nonequilibrium+conditions&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dnonequilibrium%2Bconditions"><span id="translatedtitle">Nonequilibrium ionization in <span class="hlt">solar</span> and stellar <span class="hlt">winds</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dupree, A. K.; Moore, R. T.; Shapiro, P. R.</p> <p>1979-01-01</p> <p>Substantial and systematic departures from ionization equilibrium can occur in the <span class="hlt">solar</span> transition region and corona when mass outflows are present. Modeling calculations illustrate the general characteristics of the ionization balance in such regions. The presence of nonequilibrium conditions suggests a natural explanation for the extended region of EUV line emission that is observed above the <span class="hlt">solar</span> limb. Comparison with observations of a coronal hole on the disk indicates that outflow may not start until temperatures of about 250,000 K are reached. Additional consequences include a diminution of the density discrepancy between ultraviolet and radio observations of coronal holes, and potential effects on the energy balance in <span class="hlt">solar</span> and stellar atmospheres undergoing mass loss.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22126712','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22126712"><span id="translatedtitle">HEMISPHERIC ASYMMETRIES IN THE POLAR <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> OBSERVED BY ULYSSES NEAR THE MINIMA OF <span class="hlt">SOLAR</span> CYCLES 22 AND 23</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ebert, R. W.; Dayeh, M. A.; Desai, M. I.; McComas, D. J.; Pogorelov, N. V.</p> <p>2013-05-10</p> <p>We examined <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and interplanetary magnetic field (IMF) observations from Ulysses' first and third orbits to study hemispheric differences in the properties of the <span class="hlt">solar</span> <span class="hlt">wind</span> and IMF originating from the Sun's large polar coronal holes (PCHs) during the declining and minimum phase of <span class="hlt">solar</span> cycles 22 and 23. We identified hemispheric asymmetries in several parameters, most notably {approx}15%-30% south-to-north differences in averages for the <span class="hlt">solar</span> <span class="hlt">wind</span> density, mass flux, dynamic pressure, and energy flux and the radial and total IMF magnitudes. These differences were driven by relatively larger, more variable <span class="hlt">solar</span> <span class="hlt">wind</span> density and radial IMF between {approx}36 Degree-Sign S-60 Degree-Sign S during the declining phase of <span class="hlt">solar</span> cycles 22 and 23. These observations indicate either a hemispheric asymmetry in the PCH output during the declining and minimum phase of <span class="hlt">solar</span> cycles 22 and 23 with the southern hemisphere being more active than its northern counterpart, or a <span class="hlt">solar</span> cycle effect where the PCH output in both hemispheres is enhanced during periods of higher <span class="hlt">solar</span> activity. We also report a strong linear correlation between these <span class="hlt">solar</span> <span class="hlt">wind</span> and IMF parameters, including the periods of enhanced PCH output, that highlight the connection between the <span class="hlt">solar</span> <span class="hlt">wind</span> mass and energy output and the Sun's magnetic field. That these enhancements were not matched by similar sized variations in <span class="hlt">solar</span> <span class="hlt">wind</span> speed points to the mass and energy responsible for these increases being added to the <span class="hlt">solar</span> <span class="hlt">wind</span> while its flow was subsonic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMSM11B1625R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMSM11B1625R"><span id="translatedtitle">Optimizing Coronal and <span class="hlt">Solar</span> <span class="hlt">Wind</span> Model Inputs with Data Assimilation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rigler, E.; Arge, C.; Mayer, L.</p> <p>2008-12-01</p> <p>The Wang-Sheeley-Arge (WSA) model uses line-of-sight observations of the Sun's surface magnetic field as input to a magnetostatic potential field source surface (PFSS) model of coronal expansion, which is in turn used to determine the ambient <span class="hlt">solar</span> <span class="hlt">wind</span> speed and IMF polarity. Despite its relative simplicity, the WSA does a very reasonable job of predicting large-scale, persistent structures in the <span class="hlt">solar</span> <span class="hlt">wind</span>. In fact, in the absence of transient events like coronal mass ejections (CMEs), the primary error source for WSA predictions often appears to be related to errors in its <span class="hlt">solar</span> magnetogram inputs. We employ a data assimilation scheme that augments the usual model state vector with variables that modify the WSA's magnetogram inputs in a manner that minimizes WSA prediction errors when compared to in situ measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011ASPC..444...99A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011ASPC..444...99A"><span id="translatedtitle">Improving Data Drivers for Coronal and <span class="hlt">Solar</span> <span class="hlt">Wind</span> Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arge, C. N.; Henney, C. J.; Koller, J.; Toussaint, W. A.; Harvey, J. W.; Young, S.</p> <p>2011-10-01</p> <p>Global estimates of the <span class="hlt">solar</span> photospheric magnetic field distribution are critical for space weather forecasting. These global maps are the essential data input for accurate modeling of the corona and <span class="hlt">solar</span> <span class="hlt">wind</span>, which is vital for gaining the basic understanding necessary to improve space weather forecasting models. We are now testing the global photospheric field maps generated by the Air Force Data Assimilative Photospheric flux Transport (ADAPT) model as input to the Wang-Sheeley-Arge (WSA) coronal and <span class="hlt">solar</span> <span class="hlt">wind</span> model. ADAPT incorporates data assimilation within a modified version of the Worden & Harvey photospheric magnetic flux transport model to provide an instantaneous snapshot of the global photospheric field distribution compared to that of traditional synoptic maps. In this paper we provide an overview of the WSA and ADAPT models, plus discuss preliminary results obtained from WSA when using a traditional versus an ADAPT photospheric field synoptic map as its input.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6442366','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6442366"><span id="translatedtitle">Global aspects of stream evolution in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gosling, J.T.</p> <p>1984-01-01</p> <p>A spatially variable coronal expansion, when coupled with <span class="hlt">solar</span> rotation, leads to the formation of high speed <span class="hlt">solar</span> <span class="hlt">wind</span> streams which evolve considerably with increasing heliocentric distance. Initially the streams steepen for simple kinematic reasons, but this steepening is resisted by pressure forces, leading eventually to the formation of forward-reverse shock pairs in the distant heliosphere. The basic physical processes responsible for stream steepening an evolution are explored and model calculations are compared with actual spacecraft observations of the process. The <span class="hlt">solar</span> <span class="hlt">wind</span> stream evolution problem is relatively well understood both observationally and theoretically. Tools developed in achieving this understanding should be applicable to other astrophysical systems where a spatially or temporally variable outflow is associated with a rotating object. 27 references, 13 figures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=PIA11150&hterms=solar+panel&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsolar%2Bpanel','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=PIA11150&hterms=solar+panel&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsolar%2Bpanel"><span id="translatedtitle"><span class="hlt">Solar</span> Panel Buffeted by <span class="hlt">Wind</span> at Phoenix Site</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2008-01-01</p> <p><p/> <span class="hlt">Winds</span> were strong enough to cause about a half a centimeter (.19 inch) of motion of a <span class="hlt">solar</span> panel on NASA's Phoenix Mars lander when the lander's Surface Stereo Imager took this picture on Aug. 31, 2008, during the 96th Martian day since landing. <p/> The lander's telltale <span class="hlt">wind</span> gauge has been indicating <span class="hlt">wind</span> speeds of about 4 meters per second (9 miles per hour) during late mornings at the site. <p/> These conditions were anticipated and the <span class="hlt">wind</span> is not expected to do any harm to the lander. <p/> The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://lasp.colorado.edu/cism/text/Vassiliadis_2002_Long_Term_SAMPEX.pdf','EPRINT'); return false;" href="http://lasp.colorado.edu/cism/text/Vassiliadis_2002_Long_Term_SAMPEX.pdf"><span id="translatedtitle">Long-term-average, <span class="hlt">solar</span> cycle, and seasonal response of magnetospheric energetic electrons to the <span class="hlt">solar</span> <span class="hlt">wind</span> speed</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>Long-term-average, <span class="hlt">solar</span> cycle, and seasonal response of magnetospheric energetic electrons to the <span class="hlt">solar</span> <span class="hlt">wind</span> speed D. Vassiliadis,1 A. J. Klimas,2 S. G. Kanekal,3 D. N. Baker,3 and R. S. Weigel4. [1] Among the interplanetary activity parameters the <span class="hlt">solar</span> <span class="hlt">wind</span> speed is the one best correlated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021452&hterms=solar+term&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bterm','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021452&hterms=solar+term&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bterm"><span id="translatedtitle">Long-term velocity enhancements in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gazis, P. R.; Richardson, J. D.; Paularena, K. I.</p> <p>1995-01-01</p> <p>Throughout most of the last three <span class="hlt">solar</span> cycles, the Pioneer 10, Pioneer 11, Voyager 2, IMP 8, and Pioneer Venus Orbiter spacecraft have observed long-term enhancements in <span class="hlt">solar</span> <span class="hlt">wind</span> velocity. These enhancements are typically on the order of 100-200 km/s, with durations on the order of several months to over a year. They are observed over a range of heliocentric distances that ranges from 0.72 to more than 60 AU, which suggests that they are a characteristic feature throughout the entire heliosphere, at least in the vicinity of the <span class="hlt">solar</span> equator. They appear to be related to the 'long term velocity shifts' reported by Gazis [1987], but are much more widespread. Since the last <span class="hlt">solar</span> minimum, they have recurred with the 13-year periodicity reported by Richardson et al [1994], but prior to the last <span class="hlt">solar</span> minimum there were long intervals were his periodicity was different or absent. We examine and characterize these long-term velocity enhancements and compare them to shorter-term variations in the <span class="hlt">solar</span> <span class="hlt">wind</span> such as CMEs, interaction regions, merged interaction regions (MIRs) and global merged interaction regions (GMIRs).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRA..120.2494M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRA..120.2494M"><span id="translatedtitle">An optimum <span class="hlt">solar</span> <span class="hlt">wind</span> coupling function for the AL index</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McPherron, Robert L.; Hsu, Tung-Shin; Chu, Xiangning</p> <p>2015-04-01</p> <p>We define a coupling function as a product of <span class="hlt">solar</span> <span class="hlt">wind</span> factors that partially linearizes the relation between it and a magnetic index. We consider functions that are a product of factors of <span class="hlt">solar</span> <span class="hlt">wind</span> speed V, density N, transverse magnetic field B?, and interplanetary magnetic field (IMF) clock angle ?c each raised to a different power. The index is the auroral lower (AL index) which monitors the strength of the westward electrojet. <span class="hlt">Solar</span> <span class="hlt">wind</span> data 1995-2014 provide hour averages of the factors needed to calculate optimum exponents. Nonlinear inversion determines both the exponents and linear prediction filters of short data segments. The averages of all exponents are taken as optimum exponents and for V, N, B?, and sin(?c/2) are [1.92, 0.10, 0.79, 3.67] with errors in the second decimal. Hourly values from 1966 to 2014 are used next to calculate the optimum function (opn) and the functions VBs (eys), epsilon (eps), and universal coupling function (ucf). A yearlong window is advanced by 27 days calculating linear prediction filters for the four functions. The functions eps, eys, ucf, and opn, respectively, predict 43.7, 61.2, 65.6, and 68.3% of AL variance. The opn function is 2.74% better than ucf with a confidence interval 2.60-2.86%. Coupling strength defined as the sum of filter weights (nT/mV/m) is virtually identical for all functions and varies systematically with the <span class="hlt">solar</span> cycle being strongest (188 nT/mV/m) at <span class="hlt">solar</span> minimum and weakest (104) at <span class="hlt">solar</span> maximum. Saturation of the polar cap potential approaching <span class="hlt">solar</span> maximum may explain the variation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMGC52B..03J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMGC52B..03J"><span id="translatedtitle">Physical-Statistical Downscaling of Model <span class="hlt">Wind</span> Speed and <span class="hlt">Solar</span> Radiation: Forecasting <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Energy in Nevada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, J.; Koracin, D.; King, K. C.</p> <p>2011-12-01</p> <p>High temporal variability in <span class="hlt">wind</span> speed and downward shortwave flux at ground surface has been evidenced by observations. The values also change spatially due to topography, cloud cover and other characteristics of the planetary boundary layer. Numerical weather prediction provides grid-scale resolved values; however, the sub-grid-scale part generally contributes more to variances of model <span class="hlt">wind</span> speed and/or <span class="hlt">solar</span> radiation. This part is parameterized, and not explicitly resolved. Electricity integration costs for <span class="hlt">wind</span> and/or <span class="hlt">solar</span> energy may be decreased if the variances and range of uncertainty are well explained to transmission system operators/electricity traders. In this study, month-long simulations in the summer and winter were conducted using the Weather Research and Forecasting (WRF) model. Observed <span class="hlt">wind</span> and <span class="hlt">solar</span> radiation data from four 50-m meteorological towers and one 80-m tower were used for evaluation of the model results and statistical analysis regarding the representativeness. Statistical characteristics of the observed and simulated data are analyzed. Physical downscaling of model <span class="hlt">wind</span> and downward shortwave flux at the ground surface was obtained, with consideration of the influence of topography, cloud cover, turbulence kinetic energy and other characteristics of the PBL. The results show that the temporal variance of shortwave flux is greater than that of the <span class="hlt">wind</span> power density, but the spatial variance of the <span class="hlt">wind</span> power density is much greater than that of the shortwave flux. Furthermore, the WRF results are compared with the Operational Multiscale Environment model with Grid Adaptivity (OMEGA) model results. Physical downscaling methods with different parameters are introduced and implemented. The representativeness of model results and observed data are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1037937','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1037937"><span id="translatedtitle">Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study: Hydropower Analysis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Acker, T.; Pete, C.</p> <p>2012-03-01</p> <p>The U.S. Department of Energy's (DOE) study of 20% <span class="hlt">Wind</span> Energy by 2030 was conducted to consider the benefits, challenges, and costs associated with sourcing 20% of U.S. energy consumption from <span class="hlt">wind</span> power by 2030. This study found that with proactive measures, no insurmountable barriers were identified to meet the 20% goal. Following this study, DOE and the National Renewable Energy Laboratory (NREL) conducted two more studies: the Eastern <span class="hlt">Wind</span> Integration and Transmission Study (EWITS) covering the eastern portion of the U.S., and the Western <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Integration Study (WWSIS) covering the western portion of the United States. The WWSIS was conducted by NREL and research partner General Electric (GE) in order to provide insight into the costs, technical or physical barriers, and operational impacts caused by the variability and uncertainty of <span class="hlt">wind</span>, photovoltaic, and concentrated <span class="hlt">solar</span> power when employed to serve up to 35% of the load energy in the WestConnect region (Arizona, Colorado, Nevada, New Mexico, and Wyoming). WestConnect is composed of several utility companies working collaboratively to assess stakeholder and market needs to and develop cost-effective improvements to the western wholesale electricity market. Participants include the Arizona Public Service, El Paso Electric Company, NV Energy, Public Service of New Mexico, Salt River Project, Tri-State Generation and Transmission Cooperative, Tucson Electric Power, Xcel Energy and the Western Area Power Administration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21574692','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21574692"><span id="translatedtitle">A MODEL FOR THE SOURCES OF THE SLOW <span class="hlt">SOLAR</span> <span class="hlt">WIND</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Antiochos, S. K.; Mikic, Z.; Titov, V. S.; Lionello, R.; Linker, J. A.</p> <p>2011-04-20</p> <p>Models for the origin of the slow <span class="hlt">solar</span> <span class="hlt">wind</span> must account for two seemingly contradictory observations: the slow <span class="hlt">wind</span> has the composition of the closed-field corona, implying that it originates from the continuous opening and closing of flux at the boundary between open and closed field. On the other hand, the slow <span class="hlt">wind</span> also has large angular width, up to {approx}60{sup 0}, suggesting that its source extends far from the open-closed boundary. We propose a model that can explain both observations. The key idea is that the source of the slow <span class="hlt">wind</span> at the Sun is a network of narrow (possibly singular) open-field corridors that map to a web of separatrices and quasi-separatrix layers in the heliosphere. We compute analytically the topology of an open-field corridor and show that it produces a quasi-separatrix layer in the heliosphere that extends to angles far from the heliospheric current sheet. We then use an MHD code and MDI/SOHO observations of the photospheric magnetic field to calculate numerically, with high spatial resolution, the quasi-steady <span class="hlt">solar</span> <span class="hlt">wind</span>, and magnetic field for a time period preceding the 2008 August 1 total <span class="hlt">solar</span> eclipse. Our numerical results imply that, at least for this time period, a web of separatrices (which we term an S-web) forms with sufficient density and extent in the heliosphere to account for the observed properties of the slow <span class="hlt">wind</span>. We discuss the implications of our S-web model for the structure and dynamics of the corona and heliosphere and propose further tests of the model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007840','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007840"><span id="translatedtitle">A Model for the Sources of the Slow <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Antiochos, Spiro K.; Mikic, Z.; Titov, V. S.; Lionello, R.; Linker, J. A.</p> <p>2010-01-01</p> <p>Models for the origin of the slow <span class="hlt">solar</span> <span class="hlt">wind</span> must account for two seemingly contradictory observations: The slow <span class="hlt">wind</span> has the composition of the closed-field corona, implying that it originates from the continuous opening and closing of flux at the boundary between open and closed field. On the other hand, the slow <span class="hlt">wind</span> has large angular width, up to approximately 60 degrees, suggesting that its source extends far from the open-closed boundary. We propose a model that can explain both observations. The key idea is that the source of the slow <span class="hlt">wind</span> at the Sun is a network of narrow (possibly singular) open-field corridors that map to a web of separatrices and quasi-separatrix layers in the heliosphere. We compute analytically the topology of an open-field corridor and show that it produces a quasi-separatrix layer in the heliosphere that extends to angles far front the heliospheric current sheet. We then use an MHD code and MIDI/SOHO observations of the photospheric magnetic field to calculate numerically, with high spatial resolution, the quasi-steady <span class="hlt">solar</span> <span class="hlt">wind</span> and magnetic field for a time period preceding the August 1, 2008 total <span class="hlt">solar</span> eclipse. Our numerical results imply that, at least for this time period, a web of separatrices (which we term an S-web) forms with sufficient density and extent in the heliosphere to account for the observed properties of the slow <span class="hlt">wind</span>. We discuss the implications of our S-web model for the structure and dynamics of the corona and heliosphere, and propose further tests of the model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21163475','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21163475"><span id="translatedtitle">Some remarks on waves in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kellogg, P. J.; Goetz, K.; Monson, S. J.; Balogh, A.; Forsyth, R. J.</p> <p>1996-07-20</p> <p>Waves are significant to the <span class="hlt">solar</span> <span class="hlt">wind</span> in two ways--as modifiers of the particle distribution functions, and as diagnostics. In addition, the <span class="hlt">solar</span> <span class="hlt">wind</span> serves as an important laboratory for the study of plasma wave processes, as it is possible to make detailed measurements of phenomena which are too small to be easily measured by laboratory sized sensors. The waves, both electromagnetic and electrostatic, which are part of the <span class="hlt">solar</span> type III burst phenomenon, have been extensively studied as examples of nonlinear plasma phenomena, and also used as remote sensors to trace the <span class="hlt">solar</span> magnetic field. The observations made by Ulysses show that the field can be traced in this way out to perhaps a little more than an A.U., but then the electromagnetic part of the type III burst fades out. Nevertheless, sometimes Langmuir waves appear at Ulysses at an appropriate extrapolated time. This seems to support the picture in which the electromagnetic waves at the fundamental plasma frequency are trapped in density fluctuations. Recently it has been found that Langmuir waves are associated with magnetic holes. This may help to elucidate the nature of magnetic holes. Nonlinear processes are important in the transformation of wave energy to particle energy. Some recent examples from <span class="hlt">Wind</span> data are shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010RScI...81k1301J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010RScI...81k1301J"><span id="translatedtitle">Invited Article: Electric <span class="hlt">solar</span> <span class="hlt">wind</span> sail: Toward test missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Janhunen, P.; Toivanen, P. K.; Polkko, J.; Merikallio, S.; Salminen, P.; Haeggström, E.; Seppänen, H.; Kurppa, R.; Ukkonen, J.; Kiprich, S.; Thornell, G.; Kratz, H.; Richter, L.; Krömer, O.; Rosta, R.; Noorma, M.; Envall, J.; Lätt, S.; Mengali, G.; Quarta, A. A.; Koivisto, H.; Tarvainen, O.; Kalvas, T.; Kauppinen, J.; Nuottajärvi, A.; Obraztsov, A.</p> <p>2010-11-01</p> <p>The electric <span class="hlt">solar</span> <span class="hlt">wind</span> sail (E-sail) is a space propulsion concept that uses the natural <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure for producing spacecraft thrust. In its baseline form, the E-sail consists of a number of long, thin, conducting, and centrifugally stretched tethers, which are kept in a high positive potential by an onboard electron gun. The concept gains its efficiency from the fact that the effective sail area, i.e., the potential structure of the tethers, can be millions of times larger than the physical area of the thin tethers wires, which offsets the fact that the dynamic pressure of the <span class="hlt">solar</span> <span class="hlt">wind</span> is very weak. Indeed, according to the most recent published estimates, an E-sail of 1 N thrust and 100 kg mass could be built in the rather near future, providing a revolutionary level of propulsive performance (specific acceleration) for travel in the <span class="hlt">solar</span> system. Here we give a review of the ongoing technical development work of the E-sail, covering tether construction, overall mechanical design alternatives, guidance and navigation strategies, and dynamical and orbital simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AIPC.1216..502M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AIPC.1216..502M"><span id="translatedtitle">Detection of fast nanoparticles in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meyer-Vernet, N.; Czechowski, A.; Mann, I.; Maksimovic, M.; Lecacheux, A.; Goetz, K.; Kaiser, M. L.; Cyr, O. C. St.; Bale, S. D.; Le Chat, G.</p> <p>2010-03-01</p> <p>Dust grains in the nanometer range bridge the gap between atoms and larger grains made of bulk material. Their small size embodies them with special properties. Due to their high relative surface area, they have a high charge-to-mass ratio, so that the Lorentz force in the <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field exceeds the gravitational force and other forces by a large amount, and they are accelerated to a speed of the order of magnitude of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed. When such fast nanoparticles impact a spacecraft, they produce craters whose matter vaporises and ionises, yielding transient voltages as high as do much larger grains of smaller speed. These properties are at the origin of their recent detection at 1 AU in the <span class="hlt">solar</span> <span class="hlt">wind</span>. We discuss the detection of fast nanoparticles by wave instruments of different configurations, with applications to the recent detections on STEREO/WAVES and CASSINI/RPWS. Finally we discuss the opportunities for nanoparticle detection by wave instruments on future missions and/or projects in the inner heliosphere such as Bepi-Colombo and <span class="hlt">Solar</span> Orbiter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21371727','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21371727"><span id="translatedtitle">Detection of fast nanoparticles in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Meyer-Vernet, N.; Maksimovic, M.; Lecacheux, A.; Le Chat, G.; Czechowski, A.; Mann, I.; Goetz, K.; Kaiser, M. L.; Cyr, O. C. St.; Bale, S. D.</p> <p>2010-03-25</p> <p>Dust grains in the nanometer range bridge the gap between atoms and larger grains made of bulk material. Their small size embodies them with special properties. Due to their high relative surface area, they have a high charge-to-mass ratio, so that the Lorentz force in the <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field exceeds the gravitational force and other forces by a large amount, and they are accelerated to a speed of the order of magnitude of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed. When such fast nanoparticles impact a spacecraft, they produce craters whose matter vaporises and ionises, yielding transient voltages as high as do much larger grains of smaller speed. These properties are at the origin of their recent detection at 1 AU in the <span class="hlt">solar</span> <span class="hlt">wind</span>. We discuss the detection of fast nanoparticles by wave instruments of different configurations, with applications to the recent detections on STEREO/WAVES and CASSINI/RPWS. Finally we discuss the opportunities for nanoparticle detection by wave instruments on future missions and/or projects in the inner heliosphere such as Bepi-Colombo and <span class="hlt">Solar</span> Orbiter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021400&hterms=thermodynamics+under+electric+field&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dthermodynamics%2Bunder%2Belectric%2Bfield','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021400&hterms=thermodynamics+under+electric+field&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dthermodynamics%2Bunder%2Belectric%2Bfield"><span id="translatedtitle">Measurements of electric fields in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Interpretation difficulties</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chertkov, A. D.</p> <p>1995-01-01</p> <p>The traditionally measured electric fields in the <span class="hlt">solar</span> <span class="hlt">wind</span> plasma (about 1-10 mV/m) are not the natural, primordial ones but are the result of plasma-vehicle interaction. The theory of this interaction is not complete now and current interpretation of the measurements can fail. The state of fully ionized plasma depends on the entropy of the creating source and on the process in which plasma is involved. The increasing twofold of a moving volume in the <span class="hlt">solar</span> <span class="hlt">wind</span> (with energy transfer across its surface which is comparable with its whole internal energy) is a more rapid process than the relaxation for the pressure. The presumptive source of the <span class="hlt">solar</span> <span class="hlt">wind</span> creation - the induction electric field of the <span class="hlt">solar</span> origin - has very low entropy. The state of plasma must be very far from the state of thermodynamic equilibrium. The internal energy of plasma can be contained mainly in plasma waves, resonant plasma oscillations, and electric currents. The primordial microscopic oscillating electric fields could be about 1 V/m. It can be checked by special measurements, not ruining the natural plasma state. The tool should be a dielectrical microelectroscope outside the distortion zone of the spacecraft, having been observed from the latter.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1507.05199.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1507.05199.pdf"><span id="translatedtitle">CME propagation: Where does the <span class="hlt">solar</span> <span class="hlt">wind</span> drag take over?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Sachdeva, Nishtha; Colaninno, Robin; Vourlidas, Angelos</p> <p>2015-01-01</p> <p>We investigate the Sun-Earth dynamics of a set of eight well observed <span class="hlt">solar</span> coronal mass ejections (CMEs) using data from the STEREO spacecraft. We seek to quantify the extent to which momentum coupling between these CMEs and the ambient <span class="hlt">solar</span> <span class="hlt">wind</span> (i.e., the aerodynamic drag) influences their dynamics. To this end, we use results from a 3D flux rope model fit to the CME data. We find that <span class="hlt">solar</span> <span class="hlt">wind</span> aerodynamic drag adequately accounts for the dynamics of the fastest CME in our sample. For the relatively slower CMEs, we find that drag-based models initiated below heliocentric distances ranging from 15 to 50 $R_{\\odot}$ cannot account for the observed CME trajectories. This is at variance with the general perception that the dynamics of slow CMEs are influenced primarily by <span class="hlt">solar</span> <span class="hlt">wind</span> drag from a few $R_{\\odot}$ onwards. Several slow CMEs propagate at roughly constant speeds above 15--50 $R_{\\odot}$. Drag-based models initiated above these heights therefore require negligible aerodynamic drag to explain their...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..DPPJP8017W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..DPPJP8017W"><span id="translatedtitle">Permutation entropy analysis of dynamical turbulence in the SSX MHD <span class="hlt">wind</span> tunnel and the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weck, P. J.; Hudson, E. R.; Schaffner, D. A.; Brown, M. R.; Wicks, R. T.; Lukin, V. S.</p> <p>2014-10-01</p> <p>The statistical character of turbulence in the plasma <span class="hlt">wind</span>-tunnel configuration at the Swarthmore Spheromak Experiment (SSX) and the <span class="hlt">solar</span> <span class="hlt">wind</span> is evaluated using ordinal pattern-based measures of complexity. The SSX MHD <span class="hlt">wind</span> tunnel measures fluctuations in magnetic field, velocity, and density as highly magnetized spheromaks (typical values are B ~ 0 . 1 T , n >=1020 m-3 ,and T >= 20 eV) evolve dynamically into a relaxed state. Flow speeds are measured with a visible light array. ? time series for 3 spatial directions recorded by a 16-channel, high-resolution probe array embedded in the chamber are analyzed using the permutation entropy and Jensen-Shannon statistical complexity. By calculating the position of signals on a complexity-entropy plane, the degree of stochastic, periodic, or chaotic dynamics can be evaluated. Complexity-entropy positions of SSX signals are compared to those of turbulent fluctuations in the <span class="hlt">solar</span> <span class="hlt">wind</span> and the Large Plasma Device (LAPD) as well as Hall-MHD simulations of the SSX plasma, and it is found that the dynamics in the SSX plasma source are more truly turbulent than those in the LAPD but less stochastic than fluctuations in the <span class="hlt">solar</span> <span class="hlt">wind</span>. Work supported by DOE OFES and NSF CMSO.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19940033515&hterms=cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcane','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19940033515&hterms=cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dcane"><span id="translatedtitle">Signatures of shock drivers in the <span class="hlt">solar</span> <span class="hlt">wind</span> and their dependence on the <span class="hlt">solar</span> source location</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cane, H. V.</p> <p>1993-01-01</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> and energetic ion observations following 40 interplanetary shocks with well-established <span class="hlt">solar</span> source locations have been examined in order to determine whether signatures characteristic of the coronal material forming the shock driver are present. The signatures considered include magnetic-field-aligned bidirectional ion flows observed by the ISEE 3 and IMP 8 spacecraft; bidirectional <span class="hlt">solar</span> <span class="hlt">wind</span> electron heat fluxes; <span class="hlt">solar</span> <span class="hlt">wind</span> plasma proton and electron temperature depressions; low-beta plasma; enhanced, low-variance magnetic fields; and energetic ion depressions. Several shock driver signatures are commonly observed following shocks originating from within about 50 deg of central meridian, and are generally absent for other events. We conclude that shock drivers generally extend up to about 100 deg in longitude, centered on the <span class="hlt">solar</span> source longitude. Since shocks from central meridian events are not usually associated with all the shock driver signatures examined, the absence of a driver cannot be confirmed from consideration of one of these signatures alone. We also find evidence that a few bidirectional energetic ion and <span class="hlt">solar</span> <span class="hlt">wind</span> electron heat flux events following shocks (in particular from far eastern sources) may occur on open field lines outside of shock drivers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20080045448&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwind%2Bmoon','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20080045448&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwind%2Bmoon"><span id="translatedtitle">Neutral <span class="hlt">Solar</span> <span class="hlt">Wind</span> Generated by Lunar Exospheric Dust at the Terminator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Collier, Michael R.; Stubbs, Timothy J.</p> <p>2007-01-01</p> <p>We calculate the flux of neutral <span class="hlt">solar</span> <span class="hlt">wind</span> observed on the lunar surface at the terminator due to <span class="hlt">solar</span> <span class="hlt">wind</span> protons penetrating exospheric dust with: (1) grains larger that 0.1 microns and (2) grains larger than 0.01 microns. For grains larger than 0.1 microns, the ratio of the neutral <span class="hlt">solar</span> <span class="hlt">wind</span> to <span class="hlt">solar</span> <span class="hlt">wind</span> flux is estimated to be approx.10(exp -4)-10(exp -3) at <span class="hlt">solar</span> <span class="hlt">wind</span> speeds in excess of 800 km/s, but much lower (less than 10(exp -5) at average to low <span class="hlt">solar</span> <span class="hlt">wind</span> speeds. However, when the smaller grain sizes are considered, the ratio of the neutral <span class="hlt">solar</span> <span class="hlt">wind</span> flux to <span class="hlt">solar</span> <span class="hlt">wind</span> flux is estimated to be greater than or equal to 10(exp -5) at all speeds and at speeds in excess of 700 km/s reaches 10(exp -3)-10(exp -2). These neutral <span class="hlt">solar</span> <span class="hlt">wind</span> fluxes are easily measurable with current low energy neutral atom instrumentation. Observations of neutral <span class="hlt">solar</span> <span class="hlt">wind</span> from the surface of the Moon could provide a very sensitive determination of the distribution of very small dust grains in the lunar exosphere and would provide data complementary to optical measurements at ultraviolet and visible wavelengths. Furthermore, neutral <span class="hlt">solar</span> <span class="hlt">wind</span>, unlike its ionized counterpart, is .not held-off by magnetic anomalies, and may contribute to greater space weathering than expected in certain lunar locations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SpWea..12..337B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SpWea..12..337B"><span id="translatedtitle">Predictions of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed by the probability distribution function model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bussy-Virat, C. D.; Ridley, A. J.</p> <p>2014-06-01</p> <p>The near-Earth space environment is strongly driven by the <span class="hlt">solar</span> <span class="hlt">wind</span> and interplanetary magnetic field. This study presents a model for predicting the <span class="hlt">solar</span> <span class="hlt">wind</span> speed up to 5 days in advance. Probability distribution functions (PDFs) were created that relate the current <span class="hlt">solar</span> <span class="hlt">wind</span> speed and slope to the future <span class="hlt">solar</span> <span class="hlt">wind</span> speed, as well as the <span class="hlt">solar</span> <span class="hlt">wind</span> speed to the <span class="hlt">solar</span> <span class="hlt">wind</span> speed one <span class="hlt">solar</span> rotation in the future. It was found that a major limitation of this type of technique is that the <span class="hlt">solar</span> <span class="hlt">wind</span> periodicity is close to 27 days but can be from about 22 to 32 days. Further, the optimum lag between two <span class="hlt">solar</span> rotations can change from day to day, making a prediction of the future <span class="hlt">solar</span> <span class="hlt">wind</span> speed based solely on the <span class="hlt">solar</span> <span class="hlt">wind</span> speed approximately 27 days ago quite difficult. It was found that using a linear combination of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed one <span class="hlt">solar</span> rotation ago and a prediction of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed based on the current speed and slope is optimal. The linear weights change as a function of the prediction horizon, with shorter prediction times putting more weight on the prediction based on the current <span class="hlt">solar</span> <span class="hlt">wind</span> speed and the longer prediction times based on an even spread between the two. For all prediction horizons from 8 h up to 120 h, the PDF Model is shown to be better than using the current <span class="hlt">solar</span> <span class="hlt">wind</span> speed (i.e., persistence), and better than the Wang-Sheeley-Arge Model for prediction horizons of 24 h.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050192586','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050192586"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> Fluctuations and Their Consequences on the Magnetosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Li, Xin-Lin</p> <p>2005-01-01</p> <p>Efforts have been made to extract the physical meaning of each term in our prediction model of the Dst index using the <span class="hlt">solar</span> <span class="hlt">wind</span> as the only input. The work has been published Journal of Geophysical Research (Temerin and Li, 21002). We found different terms in the model representing different current in the magnetospheric system and each current has different rise and decay times, with the symmetric ring current the slowest, then the partial ring current, then the tail current. We also have been trying to understand the physical meaning of the diffusion coefficient used in our prediction model of relativistic electron fluxes at geostationary orbit. The model reproduced the observations of MeV electron flux variations well, the diffusion coefficient had be assumed only die to local magnetic field fluctuations, leading to its 10th power dependence on the L. We have studied the theoretical derivation of the diffusion coefficient and we believe that the effect electric field fluctuations at smaller L could become more significant. We have expanded our previous radiation belt electron prediction model, which predicted MeV electron geosynchronous orbit based on <span class="hlt">solar</span> <span class="hlt">wind</span> measurements, to predict MeV electrons inside geosynchronous orbit. The model results are compared with measurements from Polar/CEPPAD. Prediction efficiencies of 0.56 and 0.54, respectively, at L=6 and L=4, have been achieved over the entire year of 1998. This work wa reported at 2003 Fall AGU and has been accepted for publication in Space Weather (Barker et al., 2005). We also have used simultaneous measurements of the upstream <span class="hlt">solar</span> <span class="hlt">wind</span> and of energetic electrons at geosynchronous orbit to analyze the response of electrons over a very wide energy range, 50 keV-6MeV, to <span class="hlt">solar</span> <span class="hlt">wind</span> variations. Enhancements of energetic electron fluxes over this whole energy range are modulated by the <span class="hlt">solar</span> <span class="hlt">wind</span> speed and the polarity of the interplanetary magnetic field (IMF). The <span class="hlt">solar</span> <span class="hlt">wind</span> speed seems to be a dominant controlling parameter for electrons of all energy. This work has been published in Space Weather (Li et al., 2005).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...808...83Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...808...83Z"><span id="translatedtitle">A Statistical Survey of Dynamic Pressure Pulses in the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Based on <span class="hlt">WIND</span> Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zuo, Pingbing; Feng, Xueshang; Xie, Yanqiong; Wang, Yi; Xu, Xiaojun</p> <p>2015-07-01</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> dynamic pressure pulse (DPP) structures, across which the dynamic pressure changes abruptly over timescales from a few seconds to several minutes, are often observed in the near-Earth space environment. The space weather effects of DPPs on the magnetosphere-ionosphere coupling system have been widely investigated in the last two decades. In this study, we perform a statistical survey on the properties of DPPs near 1 AU based on nearly 20 years of observations from the <span class="hlt">WIND</span> spacecraft. It is found that only a tiny fraction of DPPs (around 4.2%) can be regarded as interplanetary shocks. For most DPPs, the total pressure (the sum of the thermal pressure and magnetic pressure) remains in equilibrium, but there also exists a small fraction of DPPs that are not pressure-balanced. The overwhelming majority of DPPs are associated with <span class="hlt">solar</span> <span class="hlt">wind</span> disturbances, including coronal mass ejection-related flows, corotating interaction regions, as well as complex ejecta. The annual variations of the averaged occurrence rate of DPPs are roughly in phase with the <span class="hlt">solar</span> activity during <span class="hlt">solar</span> cycle 23, and during the rising phase of <span class="hlt">solar</span> cycle 24.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SoPh..290.2589S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SoPh..290.2589S"><span id="translatedtitle">Reconstruction of Helio-Latitudinal Structure of the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Proton Speed and Density</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sokó?, Justyna M.; Swaczyna, Pawe?; Bzowski, Maciej; Tokumaru, Munetoshi</p> <p>2015-09-01</p> <p>The modeling of the heliosphere requires continuous three-dimensional <span class="hlt">solar</span> <span class="hlt">wind</span> data. The in-situ out-of-ecliptic measurements are very rare, so that other methods of <span class="hlt">solar</span> <span class="hlt">wind</span> detection are needed. We use the remote-sensing data of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed from observations of interplanetary scintillation (IPS) to reconstruct spatial and temporal structures of the <span class="hlt">solar</span> <span class="hlt">wind</span> proton speed from 1985 to 2013. We developed a method of filling the data gaps in the IPS observations to obtain continuous and homogeneous <span class="hlt">solar</span> <span class="hlt">wind</span> speed records. We also present a method to retrieve the <span class="hlt">solar</span> <span class="hlt">wind</span> density from the <span class="hlt">solar</span> <span class="hlt">wind</span> speed, utilizing the invariance of the <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure and energy flux with latitude. To construct the synoptic maps of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed we use the decomposition into spherical harmonics of each of the Carrington rotation map. To fill the gaps in time we apply the singular spectrum analysis to the time series of the coefficients of spherical harmonics. We obtained helio-latitudinal profiles of the <span class="hlt">solar</span> <span class="hlt">wind</span> proton speed and density over almost three recent <span class="hlt">solar</span> cycles. The accuracy in the reconstruction is, due to computational limitations, about 20 %. The proposed methods allow us to improve the spatial and temporal resolution of the model of the <span class="hlt">solar</span> <span class="hlt">wind</span> parameters presented in our previous paper (Sokó? et al., <span class="hlt">Solar</span> Phys. 285, 167, 2013) and give a better insight into the time variations of the <span class="hlt">solar</span> <span class="hlt">wind</span> structure. Additionally, the <span class="hlt">solar</span> <span class="hlt">wind</span> density is reconstructed more accurately and it fits better to the in-situ measurements from Ulysses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20110023419&hterms=belt&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbelt','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20110023419&hterms=belt&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbelt"><span id="translatedtitle"><span class="hlt">Solar</span> Rotational Periodicities and the Semiannual Variation in the <span class="hlt">Solar</span> <span class="hlt">Wind</span>, Radiation Belt, and Aurora</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Emery, Barbara A.; Richardson, Ian G.; Evans, David S.; Rich, Frederick J.; Wilson, Gordon R.</p> <p>2011-01-01</p> <p>The behavior of a number of <span class="hlt">solar</span> <span class="hlt">wind</span>, radiation belt, auroral and geomagnetic parameters is examined during the recent extended <span class="hlt">solar</span> minimum and previous <span class="hlt">solar</span> cycles, covering the period from January 1972 to July 2010. This period includes most of the <span class="hlt">solar</span> minimum between Cycles 23 and 24, which was more extended than recent <span class="hlt">solar</span> minima, with historically low values of most of these parameters in 2009. <span class="hlt">Solar</span> rotational periodicities from S to 27 days were found from daily averages over 81 days for the parameters. There were very strong 9-day periodicities in many variables in 2005 -2008, triggered by recurring corotating high-speed streams (HSS). All rotational amplitudes were relatively large in the descending and early minimum phases of the <span class="hlt">solar</span> cycle, when HSS are the predominant <span class="hlt">solar</span> <span class="hlt">wind</span> structures. There were minima in the amplitudes of all <span class="hlt">solar</span> rotational periodicities near the end of each <span class="hlt">solar</span> minimum, as well as at the start of the reversal of the <span class="hlt">solar</span> magnetic field polarity at <span class="hlt">solar</span> maximum (approx.1980, approx.1990, and approx. 2001) when the occurrence frequency of HSS is relatively low. Semiannual equinoctial periodicities, which were relatively strong in the 1995-1997 <span class="hlt">solar</span> minimum, were found to be primarily the result of the changing amplitudes of the 13.5- and 27-day periodicities, where 13.5-day amplitudes were better correlated with heliospheric daily observations and 27-day amplitudes correlated better with Earth-based daily observations. The equinoctial rotational amplitudes of the Earth-based parameters were probably enhanced by a combination of the Russell-McPherron effect and a reduction in the <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere coupling efficiency during solstices. The rotational amplitudes were cross-correlated with each other, where the 27 -day amplitudes showed some of the weakest cross-correlations. The rotational amplitudes of the > 2 MeV radiation belt electron number fluxes were progressively weaker from 27- to 5-day periods, showing that processes in the magnetosphere act as a low-pass filter between the <span class="hlt">solar</span> <span class="hlt">wind</span> and the radiation belt. The A(sub p)/K(sub p) magnetic currents observed at subauroral latitudes are sensitive to proton auroral precipitation, especially for 9-day and shorter periods, while the A(sub p)/K(sub p) currents are governed by electron auroral precipitation for 13.5- and 27-day periodicities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17779009','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17779009"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> Control of the Earth's Electric Field.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Markson, R; Muir, M</p> <p>1980-05-30</p> <p>The sun-weather problem is placed within an electrical framework subject to experimental investigation. An explanation is suggested for how <span class="hlt">solar</span> variability modulates the earth's electric field. The <span class="hlt">solar</span> <span class="hlt">wind</span> velocity is inversely correlated with the electrical potential of the ionosphere, a measure of the overall intensity of the earth's fair-weather atmospheric electric field. In seeking a physical cause of this relationship, galactic cosmic radiation was studied and it was also found to be inversely correlated with <span class="hlt">solar</span> <span class="hlt">wind</span> velocity. Thus, the earth's electric field intensity which is maintained by worldwide thunderstorm currents-a meteorological phenomenon-varies in phase with cosmic radiation. Since cosmic radiation is the primary source of atmospheric ionization, these findings support a proposed mechanism in which <span class="hlt">solar</span> control of ionizing radiation modulates atmospheric electrification and thus possibly cloud physical processes. If the latter occurred, atmospheric energetics would be affected. Sun-weather research need no longer only consist of statistical correlations; an experimental approach is described. Establishment of a proposed geoelectric index would add a new dimension to <span class="hlt">solar</span>-terrestrial studies. PMID:17779009</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5728979','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5728979"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> control of the earth's electric field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Markson, R.; Muir, M.</p> <p>1980-05-30</p> <p>The sun-weather problem is placed within an electrical framework subject to experimental investigation. An explanation is suggested for how <span class="hlt">solar</span> variability modulates the earth's electric field. The <span class="hlt">solar</span> <span class="hlt">wind</span> velocity is inversely correlated with the electrical potential of the ionosphere, a measure of the overall intensity of the earth's fair-weather atmospheric electric field. In seeking a physical cause of this relationship, galactic cosmic radiation was studied and it was also found to be inversely correlated with <span class="hlt">solar</span> <span class="hlt">wind</span> velocity. Thus, the earth's electric field intensity which is maintained by worldwide thunderstorm currents - a meteorological phenomenon - varies in phase with cosmic radiation. Since cosmic radiation is the primary source of atmospheric ionization, these findings support a proposed mechanism in which <span class="hlt">solar</span> control of ionizing radiation modulates atmospheric electrification and thus possibly cloud physical processes. If the latter occurred, atmospheric energetics would be affected. Sun-weather research need no longer only consist of statistical correlations; an experimental approach is described. Establishment of a proposed geoelectric index would add a new dimension to <span class="hlt">solar</span>-terrestrial studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/7760930','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/7760930"><span id="translatedtitle">Nitrogen isotope abundances in the recent <span class="hlt">solar</span> <span class="hlt">wind</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, J S; Kim, Y; Marti, K; Kerridge, J F</p> <p>1995-06-01</p> <p>Although lunar crystalline rocks are essentially devoid of nitrogen, the same is not true of the lunar regolith. The nitrogen contents of individual regolith samples (which can be as high as 0.012% by mass) correlate strongly with abundances of noble gases known to be implanted in the lunar surface by <span class="hlt">solar</span> radiation, indicating that lunar regolith nitrogen is also predominantly of <span class="hlt">solar</span> origin. The large variability in 15N/14N ratios measured in different regolith samples may thus reflect long-term changes in the isotopic composition of the <span class="hlt">solar</span> radiation. But attempts to explain these variations have been hampered by the lack of any firm constraint on 15N/14N in the present <span class="hlt">solar</span> <span class="hlt">wind</span>. Here we report measurements of nitrogen isotopes from two lunar samples that have had simple (and relatively recent) exposure histories. We find that nitrogen implanted in the lunar surface during the past 10(5) to 5 x 10(7) years has a 15N/14N ratio approximately 40% higher than that in the terrestrial atmosphere, which is substantially lower than most previous estimates. This isotopic signature probably represents the best measure of 15N/14N in the present-day <span class="hlt">solar</span> <span class="hlt">wind</span>. PMID:7760930</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19730002053&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsolar%2Bwind%2Benergy','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19730002053&hterms=solar+wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsolar%2Bwind%2Benergy"><span id="translatedtitle">Conversion of magnetic field energy into kinetic energy in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Whang, Y. C.</p> <p>1972-01-01</p> <p>The outflow of the <span class="hlt">solar</span> magnetic field energy (the radial component of the Poynting vector) per steradian is inversely proportional to the <span class="hlt">solar</span> <span class="hlt">wind</span> velocity. It is a decreasing function of the heliocentric distance. When the magnetic field effect is included in the one-fluid model of the <span class="hlt">solar</span> <span class="hlt">wind</span>, the transformation of magnetic field energy into kinetic energy during the expansion process increases the <span class="hlt">solar</span> <span class="hlt">wind</span> velocity at 1 AU by 17 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1002.0297.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1002.0297.pdf"><span id="translatedtitle">Extended Coronal Heating and <span class="hlt">Solar</span> <span class="hlt">Wind</span> Acceleration Over the <span class="hlt">Solar</span> Cycle</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Cranmer, Steven R; Miralles, Mari Paz; van Ballegooijen, Adriaan A</p> <p>2010-01-01</p> <p>This paper reviews our growing understanding of the physics behind coronal heating (in open-field regions) and the acceleration of the <span class="hlt">solar</span> <span class="hlt">wind</span>. Many new insights have come from the last <span class="hlt">solar</span> cycle's worth of observations and theoretical work. Measurements of the plasma properties in the extended corona, where the primary <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration occurs, have been key to discriminating between competing theories. We describe how UVCS/SOHO measurements of coronal holes and streamers over the last 14 years have provided clues about the detailed kinetic processes that energize both fast and slow <span class="hlt">wind</span> regions. We also present a brief survey of current ideas involving the coronal source regions of fast and slow <span class="hlt">wind</span> streams, and how these change over the <span class="hlt">solar</span> cycle. These source regions are discussed in the context of recent theoretical models (based on Alfven waves and MHD turbulence) that have begun to successfully predict both the heating and acceleration in fast and slow <span class="hlt">wind</span> regions with essentially no fre...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19740060901&hterms=Collards&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DCollards','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19740060901&hterms=Collards&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DCollards"><span id="translatedtitle">Pioneer 10 observations of the <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with Jupiter</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wolfe, J. H.; Mihalov, J. D.; Collard, H. R.; Mckibbin, D. D.; Frank, L. A.; Intriligator, D. S.</p> <p>1974-01-01</p> <p>Detailed analysis of the Pioneer 10 plasma analyzer experiment flight data during the Jupiter flyby in late November and early December 1973 has been performed. The observations show that the interaction of Jupiter's magnetic field with the <span class="hlt">solar</span> <span class="hlt">wind</span> is similar in many ways to that at earth, but the scale size is over 100 times larger. Jupiter is found to have a detached standing bow shock wave of high Alfven Mach number. Like the earth, Jupiter has a prominent magnetopause that deflects the magnetosheath plasma and excludes its direct entry into the Jovian magnetosphere. Unlike that of the earth, the sunward hemisphere of Jupiter's outer magnetosphere is found to be highly inflated with thermal plasma and a high-beta region that is highly responsive to changes in <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740018157','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740018157"><span id="translatedtitle">Pioneer 10 observations of the <span class="hlt">solar</span> <span class="hlt">wind</span> interation with Jupiter</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wolfe, J. H.; Mihalov, J. D.; Collard, H. R.; Mckibbin, D. D.; Frank, L. A.; Intriligator, D. S.</p> <p>1974-01-01</p> <p>Pioneer 10 Plasma Analyzer experiment flight data during the Jupiter flyby are presented. The observations show that the interaction of Jupiter's magnetic field with the <span class="hlt">solar</span> <span class="hlt">wind</span> is similar in many ways to that at earth, but the scale size is over 100 times larger. Jupiter is found to have a detached standing bow shock wave of high Alfven Mach number. Jupiter has a prominent magnetopause which deflects the magnetosheath plasma and excludes its direct entry into the Jovian magnetosphere. The sunward hemisphere of Jupiter's outer magnetosphere is found to be highly inflated with thermal plasma and a high beta region which is highly responsive to changes in <span class="hlt">solar</span> <span class="hlt">wind</span> dynamic pressure. Observational arguments are presented which tend to discount a thin disklike magnetosphere but, rather, favor a Jovian magnetosphere, albeit probabily considerably flattened as compared to the earth's magnetosphere, yet still with reasonable thickness. Results concerning the shock jump conditions, the magnetosheath flow field and inferred internal magnetospheric plasma are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760024031','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760024031"><span id="translatedtitle">Mass fractionation of the lunar surface by <span class="hlt">solar</span> <span class="hlt">wind</span> sputtering</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Switkowski, Z. E.; Haff, P. K.; Tombrello, T. A.; Burnett, D. S.</p> <p>1975-01-01</p> <p>The sputtering of the lunar surface by the <span class="hlt">solar</span> <span class="hlt">wind</span> is examined as a possible mechanism of mass fractionation. Simple arguments based on current theories of sputtering and the ballistics of the sputtered atoms suggest that most ejected atoms will have sufficiently high energy to escape lunar gravity. However, the fraction of atoms which falls back to the surface is enriched in the heavier atomic components relative to the lighter ones. This material is incorporated into the heavily radiation-damaged outer surfaces of grains where it is subject to resputtering. Over the course of several hundred years an equilibrium surface layer, enriched in heavier atoms, is found to form. The dependence of the calculated results upon the sputtering rate and on the details of the energy spectrum of sputtered particles is investigated. It is concluded that mass fractionation by <span class="hlt">solar</span> <span class="hlt">wind</span> sputtering is likely to be an important phenomenon on the lunar surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22068812','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22068812"><span id="translatedtitle">Generation of residual energy in the turbulent <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gogoberidze, G.</p> <p>2012-10-15</p> <p>In situ observations of the fluctuating <span class="hlt">solar</span> <span class="hlt">wind</span> flow show that the energy of magnetic field fluctuations always exceeds that of the kinetic energy, and therefore the difference between the kinetic and magnetic energies, known as the residual energy, is always negative. The same behaviour is found in numerical simulations of magnetohydrodynamic turbulence. We study the dynamics of the residual energy for strong, anisotropic, critically balanced magnetohydrodynamic turbulence using the eddy damped quasi-normal Markovian approximation. Our analysis shows that for stationary critically balanced magnetohydrodynamic turbulence, negative residual energy will always be generated by nonlinear interacting Alfven waves. This offers a general explanation for the observation of negative residual energy in <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence and in the numerical simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/0709.4505v1','EPRINT'); return false;" href="http://arxiv.org/pdf/0709.4505v1"><span id="translatedtitle">The <span class="hlt">Solar</span> <span class="hlt">Wind</span> Around Pluto (SWAP) Instrument Aboard New Horizons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>D. McComas; F. Allegrini; F. Bagenal; P. Casey; P. Delamere; D. Demkee; G. Dunn; H. Elliott; J. Hanley; K. Johnson; J. Langle; G. Miller; S. Pope; M. Reno; B. Rodriguez; N. Schwadron; P. Valek; S. Weidner</p> <p>2007-09-27</p> <p>The <span class="hlt">Solar</span> <span class="hlt">Wind</span> Around Pluto (SWAP) instrument on New Horizons will measure the interaction between the <span class="hlt">solar</span> <span class="hlt">wind</span> and ions created by atmospheric loss from Pluto. These measurements provide a characterization of the total loss rate and allow us to examine the complex plasma interactions at Pluto for the first time. Constrained to fit within minimal resources, SWAP is optimized to make plasma-ion measurements at all rotation angles as the New Horizons spacecraft scans to image Pluto and Charon during the flyby. In order to meet these unique requirements, we combined a cylindrically symmetric retarding potential analyzer (RPA) with small deflectors, a top-hat analyzer, and a redundant/coincidence detection scheme. This configuration allows for highly sensitive measurements and a controllable energy passband at all scan angles of the spacecraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012Ge%26Ae..52.1113G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012Ge%26Ae..52.1113G"><span id="translatedtitle">Impact of <span class="hlt">solar</span> <span class="hlt">wind</span> tangential discontinuities on the Earth's magnetosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grib, S. A.</p> <p>2012-12-01</p> <p>The collision of a <span class="hlt">solar</span> <span class="hlt">wind</span> tangential discontinuity with the bow shock and magnetopause is considered in the scope of an MHD approximation. Using MHD methods of trial calculations and generalized shock polars, it has been indicated that a fast shock refracted into the magnetosheath originates when density increases across a tangential discontinuity and a fast rarefaction wave is generated when density decreases at this discontinuity. It has been indicated that a shock front shift under the action of collisions with a tangential discontinuity is experimentally observed and a fast bow shock can be transformed into a slow shock. Using a specific event as an example, it has been demonstrated that <span class="hlt">solar</span> <span class="hlt">wind</span> tangential discontinuity affects the geomagnetic field behavior.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19870029831&hterms=radio+work&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dradio%2Bwork','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19870029831&hterms=radio+work&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dradio%2Bwork"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> control of Jupiter's decametric radio emission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barrow, C. H.; Genova, F.; Desch, M. D.</p> <p>1986-01-01</p> <p>Observations of the <span class="hlt">solar</span> <span class="hlt">wind</span> close to Jupiter are compared with the decametric radio emission (DAM), using data recorded by Voyager 1 and Voyager 2 during 1979. The Non-Io DAM, recorded by both spacecraft and combined using the superposed epoch technique, is found to correlate with the <span class="hlt">solar</span> <span class="hlt">wind</span> density and velocity, as well as with the interplanetary magnetic field (IMF) magnitude. In agreement with earlier work using ground-based observations, there are indications that the Non-Io DAM is somehow associated with magnetic sector structure although the precise details of the relationship are still not known and it is not clear if this is a fundamental effect or some secondary effect of intercorrelation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1505.00727.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1505.00727.pdf"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> modeling: a computational tool for the classroom</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Woolsey, Lauren N</p> <p>2015-01-01</p> <p>This article presents a Python model and library that can be used for student investigation of the application of fundamental physics on a specific problem: the role of magnetic field in <span class="hlt">solar</span> <span class="hlt">wind</span> acceleration. The paper begins with a short overview of the open questions in the study of the <span class="hlt">solar</span> <span class="hlt">wind</span> and how they relate to many commonly taught physics courses. The physics included in the model, The Efficient Modified Parker Equation Solving Tool (TEMPEST), is laid out for the reader. Results using TEMPEST on a magnetic field structure representative of the minimum phase of the Sun's activity cycle are presented and discussed. The paper suggests several ways to use TEMPEST in an educational environment and provides access to the current version of the code.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.453L..64C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.453L..64C"><span id="translatedtitle">Magnetic field rotations in the <span class="hlt">solar</span> <span class="hlt">wind</span> at kinetic scales</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, C. H. K.; Matteini, L.; Burgess, D.; Horbury, T. S.</p> <p>2015-10-01</p> <p>The <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field contains rotations at a broad range of scales, which have been extensively studied in the magnetohydrodynamics range. Here, we present an extension of this analysis to the range between ion and electron kinetic scales. The distribution of rotation angles was found to be approximately lognormal, shifting to smaller angles at smaller scales almost self-similarly, but with small, statistically significant changes of shape. The fraction of energy in fluctuations with angles larger than ? was found to drop approximately exponentially with ?, with e-folding angle 9.8° at ion scales and 0.66° at electron scales, showing that large angles (? > 30°) do not contain a significant amount of energy at kinetic scales. Implications for kinetic turbulence theory and the dissipation of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1503.00695.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1503.00695.pdf"><span id="translatedtitle">Predicted Impacts of Proton Temperature Anisotropy on <span class="hlt">Solar</span> <span class="hlt">Wind</span> Turbulence</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Klein, Kristopher G</p> <p>2015-01-01</p> <p>Particle velocity distributions measured in the weakly collisional <span class="hlt">solar</span> <span class="hlt">wind</span> are frequently found to be non-Maxwellian, but how these non-Maxwellian distributions impact the physics of plasma turbulence in the <span class="hlt">solar</span> <span class="hlt">wind</span> remains unanswered. Using numerical solutions of the linear dispersion relation for a collisionless plasma with a bi-Maxwellian proton velocity distribution, we present a unified framework for the four proton temperature anisotropy instabilities, identifying the associated stable eigenmodes, highlighting the unstable region of wavevector space, and presenting the properties of the growing eigenfunctions. Based on physical intuition gained from this framework, we address how the proton temperature anisotropy impacts the nonlinear dynamics of the \\Alfvenic fluctuations underlying the dominant cascade of energy from large to small scales and how the fluctuations driven by proton temperature anisotropy instabilities interact nonlinearly with each other and with the fluctuations of the large-scal...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830026604','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830026604"><span id="translatedtitle">Coronal sources of the intrastream structure of the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sullivan, J. D.; Bridge, H. S.</p> <p>1983-01-01</p> <p>Short time scale changes in the bulk speed were found not to coincide with X-ray transients near the sub-earth point nor with the number of X-ray bright points within a coronal hole and near the equator. The changes in bulk speed, it is shown, are associated with changes in light areas in a hole which may be associated with the opening or closing of magnetic field lines within the coronal hole. That there is a causal connection between these sudden changes (apperance or disappearance) in light area and sudden changes in the bulk speed of the <span class="hlt">solar</span> <span class="hlt">wind</span> is further evidenced by the spatial proximity on the Sun of these changing light regions to the source position of stream lines from Levine's model that connect into the same <span class="hlt">solar</span> <span class="hlt">wind</span> streams.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19740034913&hterms=Kinetic+theory&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D%2528Kinetic%2Btheory%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19740034913&hterms=Kinetic+theory&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D%2528Kinetic%2Btheory%2529"><span id="translatedtitle">Kinetic theory analysis of <span class="hlt">solar</span> <span class="hlt">wind</span> interaction with planetary objects</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, S. T.; Dryer, M.</p> <p>1973-01-01</p> <p>A purely kinetic treatment is proposed for the interaction of the <span class="hlt">solar</span> <span class="hlt">wind</span> with any small planetary object. Small refers to those cases where the <span class="hlt">solar</span> <span class="hlt">wind</span> proton's thermal gyroradius is arbitrarily taken to be greater than 0.1 radius of the object under investigation. The 'object' may possibly include an ionosphere or magnetosphere. The collisionless Boltzmann equation, neglecting the magnetic field, is used to calculate steady-state profiles of density and velocity around the obstacle. A low density plasma void in the umbral region and a compression in the penumbral region are clearly found. The present technique, despite its neglect of the interplanetary magnetic field, is proposed as an alternative zeroth order approach to the continuum, local magnetic anomaly, and guiding center approaches used by others for the particular case of moon. Some recent, potentially relevant, observations on and in front of the moon are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1108.6072v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1108.6072v1"><span id="translatedtitle">Residual energy in magnetohydrodynamic turbulence and in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Stanislav Boldyrev; Jean Carlos Perez; Vladimir Zhdankin</p> <p>2011-08-30</p> <p>Recent observations indicate that kinetic and magnetic energies are not in equipartition in the <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence. Rather, magnetic fluctuations are more energetic and have somewhat steeper energy spectrum compared to the velocity fluctuations. This leads to the presence of the so-called residual energy E_r=E_v-E_b in the inertial interval of turbulence. This puzzling effect is addressed in the present paper in the framework of weak turbulence theory. Using a simple model of weakly colliding Alfv\\'en waves, we demonstrate that the kinetic-magnetic equipartition indeed gets broken as a result of nonlinear interaction of Alfv\\'en waves. We establish that magnetic energy is indeed generated more efficiently as a result of these interactions, which proposes an explanation for the <span class="hlt">solar</span> <span class="hlt">wind</span> observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1507.07782.pdf','EPRINT'); return false;" href="http://arxiv.org/pdf/1507.07782.pdf"><span id="translatedtitle">Magnetic Field Rotations in the <span class="hlt">Solar</span> <span class="hlt">Wind</span> at Kinetic Scales</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Chen, C H K; Burgess, D; Horbury, T S</p> <p>2015-01-01</p> <p>The <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field contains rotations at a broad range of scales, which have been extensively studied in the MHD range. Here we present an extension of this analysis to the range between ion and electron kinetic scales. The distribution of rotation angles was found to be approximately log-normal, shifting to smaller angles at smaller scales almost self-similarly, but with small, statistically significant changes of shape. The fraction of energy in fluctuations with angles larger than $\\alpha$ was found to drop approximately exponentially with $\\alpha$, with e-folding angle $9.8^\\circ$ at ion scales and $0.66^\\circ$ at electron scales, showing that large angles ($\\alpha > 30^\\circ$) do not contain a significant amount of energy at kinetic scales. Implications for kinetic turbulence theory and the dissipation of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013MS%26E...52g2003C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013MS%26E...52g2003C"><span id="translatedtitle">A desalination plant with <span class="hlt">solar</span> and <span class="hlt">wind</span> energy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, H.; Ye, Z.; Gao, W.</p> <p>2013-12-01</p> <p>The shortage of freshwater resources has become a worldwide problem. China has a water shortage, although the total amount of water resources is the sixth in the world, the per capita water capacity is the 121th (a quarter of the world's per capita water capacity), and the United Nations considers China one of the poorest 13 countries in the world in terms of water. In order to increase the supply of fresh water, a realistic way is to make full use of China's long and narrow coastline for seawater desalination. This paper discusses a sea water desalination device, the device adopts distillation, uses the greenhouse effect principle and <span class="hlt">wind</span> power heating principle, and the two-type start is used to solve the problem of vertical axis <span class="hlt">wind</span> turbine self-starting. Thrust bearings are used to ensure the stability of the device, and to ensure absorbtion of <span class="hlt">wind</span> energy and <span class="hlt">solar</span> energy, and to collect evaporation of water to achieve desalination. The device can absorb <span class="hlt">solar</span> and <span class="hlt">wind</span> energy instead of input energy, so it can be used in ship, island and many kinds of environment. Due to the comprehensive utilization of <span class="hlt">wind</span> power and <span class="hlt">solar</span> power, the efficiency of the device is more than other passive sea water desalting plants, the initial investment and maintenance cost is lower than active sea water desalting plant. The main part of the device cannot only be used in offshore work, but can also be used in deep sea floating work, so the device can utilise deep sea energy. In order to prove the practicability of the device, the author has carried out theory of water production calculations. According to the principle of conservation of energy, the device ais bsorbing <span class="hlt">solar</span> and <span class="hlt">wind</span> power, except loose lost part which is used for water temperature rise and phase transition. Assume the inflow water temperature is 20 °C, outflow water temperature is 70 °C, the energy utilization is 60%, we can know that the water production quantity is 8 kg/ m2 per hour. Comparing with the disk <span class="hlt">solar</span> distillation apparatus, of which water production quantity is only 3-4kg/m2 per hour only in sunny day, but can't be used at night, the water production quantity is highly increased. So the device should have a good application prospect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002ESASP.506...43F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002ESASP.506...43F"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">wind</span> quasi-invariant as a heliospheric index of <span class="hlt">solar</span> activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fainberg, J.; Osherovich, V. A.</p> <p>2002-12-01</p> <p>Interplanetary magnetic field strength B, <span class="hlt">solar</span> <span class="hlt">wind</span> speed v and plasma density ? all vary with sunspot numbers (SSN). The corresponding correlation coefficients (cc) are not high enough to establish any of these parameters as a close proxy for SSN. In contrast, the <span class="hlt">solar</span> <span class="hlt">wind</span> quasi-invariant [QI ? (B2/8?)/(?v2/2)] recently suggested by Osherovich, Fainberg and Stone [1999] has a high cc = 0.98 for the median yearly value for the 28 year period measured in the <span class="hlt">solar</span> <span class="hlt">wind</span> near the Earth (1 AU). For the period 1978-1989, Voyager 2 measured B, v and ? from 2 AU to 27 AU. In this paper we show that in spite of the orders of magnitude change of B and ? at large heliospheric distances, QI measured by Voyager 2 stayed in the same range and followed SSN similar to QI measured near the Earth and near Venus. These results supply an observational test for any MHD model of the <span class="hlt">solar</span> <span class="hlt">wind</span> throughout the heliosphere that attempts to include the effects of <span class="hlt">solar</span> cycle variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19790057954&hterms=dip&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Ddip','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19790057954&hterms=dip&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Ddip"><span id="translatedtitle">Magnetic dips in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dobrowolny, M.; Bavassano, B.; Mariani, F.; Ness, N.</p> <p>1979-01-01</p> <p>Using magnetic data from the Helios-1 fluxgate magnetometer, with a 0.2 s resolution, we have investigated the structure of several interplanetary discontinuities involving magnetic dips and rotations of the magnetic field vector. A minimum variance analysis illustrates the behaviour of the magnetic field through the transition. Using this analysis, quite different structures have been isolated and, in particular, narrow transitions resembling almost one dimensional reconnected neutral sheets. For the thinner cases (scale lengths of the magnetic rotation of the order or smaller than 1000 km), we find that the observed structures can be the nonlinear effect of a resistive tearing mode instability having developed on an originally one dimensional neutral sheet at the <span class="hlt">solar</span> corona.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790018882','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790018882"><span id="translatedtitle">Magnetic dips in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dobrowolny, M.; Bavassano, B.; Mariani, F.; Ness, N.; Burlaga, L. F.</p> <p>1978-01-01</p> <p>Using magnetic data from the HELIOS 1 fluxgate magnetometer, with a 0.2 sec resolution, the structures of several interplanetary discontinuities involving magnetic dips and rotations of the magnetic field vector were investigated. A minimum variance analysis illustrates the behavior of the magnetic field through the transition in the plane of its maximum variation. Using this analysis, quite different structures have been individuated and, in particular, narrow transitions resembling almost one dimensional reconnected neutral sheets. For the thinner cases (scale lengths of the magnetic rotation of the order or smaller than 1,000 km), results show the observed structures could be the nonlinear effect of a resistive tearing mode instability having developed on an originally one dimensional neutral sheet at the <span class="hlt">solar</span> corona.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSH31A4113K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSH31A4113K"><span id="translatedtitle">Langmuir Turbulence in the <span class="hlt">Solar</span> <span class="hlt">Wind</span> : Numerical Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krafft, C.; Volokitin, A.; Krasnoselskikh, V.</p> <p>2014-12-01</p> <p>Observations performed in the <span class="hlt">solar</span> <span class="hlt">wind</span> by different satellites show that electron beams accelerated in the low corona during <span class="hlt">solar</span> flares can propagate up to distances around 1 AU, that Langmuir waves' packets can be clumped into spikes with peak amplitudes three orders of magnitude above the mean and that the average level of density fluctuations in the <span class="hlt">solar</span> <span class="hlt">wind</span> plasmas can reach several percents. A Hamiltonian model is built describing the properties of Langmuir waves propagating in a plasma with random density fluctuations by the Zakharov's equations and the beam by means of particles moving self-consistently in the fields of the waves. Numerical simulations, performed using parameters relevant to <span class="hlt">solar</span> type III conditions at 1 AU, show that when the average level of density fluctuations is sufficiently low, the beam relaxation and the wave excitation processes are similar to those in a homogeneous plasma and can be described by the quasilinear equations of the weak turbulence theory. On the contrary, when the average level of density fluctuations overcomes some threshold depending on the ratio of the thermal velocity to the beam velocity, the plasma inhomogeneities crucially influence on the characteristics of the Langmuir turbulence and the beam-plasma interaction. In this case, fluxes of accelerated particles are observed, whose density and kinetic energy can be calculated as a function of the beam and plasma characteristics. Langmuir waveforms are presented in the form they would appear if recorded by a satellite moving in the <span class="hlt">solar</span> <span class="hlt">wind</span>. Comparison with recent measurements by the STEREO and <span class="hlt">WIND</span> satellites shows that their characteristic features are very similar to the observations. Moreover, wave-wave coupling and three wave decay processes are studied as a function of the average level of plasma density fluctuations. References Volokitin, V. V. Krasnoselskikh, C. Krafft, and E. Kuznetsov, Modelling of the beam-plasma interaction in a strongly inhomogeneous plasma. AIP Conf. Proc. 1539, 78 (2013). C. Krafft, A. Volokitin, V. V. Krasnoselskikh, Interaction of energetic particles with waves in strongly inhomogeneous <span class="hlt">solar</span> <span class="hlt">wind</span> plasmas, Astrophys. J., 778, 111 (2013).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JASS...31..149K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JASS...31..149K"><span id="translatedtitle">Statistical Properties of Geomagnetic Activity Indices and <span class="hlt">Solar</span> <span class="hlt">Wind</span> Parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Jung-Hee; Chang, Heon-Young</p> <p>2014-06-01</p> <p>As the prediction of geomagnetic storms is becoming an important and practical problem, conditions in the Earth¡¯s magnetosphere have been studied rigorously in terms of those in the interplanetary space. Another approach to space weather forecast is to deal with it as a probabilistic geomagnetic storm forecasting problem. In this study, we carry out detailed statistical analysis of <span class="hlt">solar</span> <span class="hlt">wind</span> parameters and geomagnetic indices examining the dependence of the distribution on the <span class="hlt">solar</span> cycle and annual variations. Our main findings are as follows: (1) The distribution of parameters obtained via the superimposed epoch method follows the Gaussian distribution. (2) When <span class="hlt">solar</span> activity is at its maximum the mean value of the distribution is shifted to the direction indicating the intense environment. Furthermore, the width of the distribution becomes wider at its maximum than at its minimum so that more extreme case can be expected. (3) The distribution of some certain heliospheric parameters is less sensitive to the phase of the <span class="hlt">solar</span> cycle and annual variations. (4) The distribution of the eastward component of the interplanetary electric field BV and the <span class="hlt">solar</span> <span class="hlt">wind</span> driving function BV2, however, appears to be all dependent on the <span class="hlt">solar</span> maximum/minimum, the descending/ascending phases of the <span class="hlt">solar</span> cycle and the equinoxes/solstices. (5) The distribution of the AE index and the Dst index shares statistical features closely with BV and BV2 compared with other heliospheric parameters. In this sense, BV and BV2 are more robust proxies of the geomagnetic storm. We conclude by pointing out that our results allow us to step forward in providing the occurrence probability of geomagnetic storms for space weather and physical modeling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/1204.4479v1','EPRINT'); return false;" href="http://arxiv.org/pdf/1204.4479v1"><span id="translatedtitle">Magnetic Discontinuities in Magnetohydrodynamic Turbulence and in the <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Vladimir Zhdankin; Stanislav Boldyrev; Joanne Mason; Jean Carlos Perez</p> <p>2012-04-19</p> <p>Recent measurements of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence report the presence of intermittent, exponentially distributed angular discontinuities in the magnetic field. In this Letter, we study whether such discontinuities can be produced by magnetohydrodynamic (MHD) turbulence. We detect the discontinuities by measuring the fluctuations of the magnetic field direction, Delta theta, across fixed spatial increments Delta x in direct numerical simulations of MHD turbulence with an imposed uniform guide field B_0. A large region of the probability density function (pdf) for Delta theta is found to follow an exponential decay, proportional to exp(-Delta theta/theta_*), with characteristic angle theta_* ~ (14 deg) (b_rms/B_0)^0.65 for a broad range of guide-field strengths. We find that discontinuities observed in the <span class="hlt">solar</span> <span class="hlt">wind</span> can be reproduced by MHD turbulence with reasonable ratios of b_rms/B_0. We also observe an excess of small angular discontinuities when Delta x becomes small, possibly indicating an increasing statistical significance of dissipation-scale structures. The structure of the pdf in this case closely resembles the two-population pdf seen in the <span class="hlt">solar</span> <span class="hlt">wind</span>. We thus propose that strong discontinuities are associated with inertial-range MHD turbulence, while weak discontinuities emerge from near-dissipation-range turbulence. In addition, we find that the structure functions of the magnetic field direction exhibit anomalous scaling exponents, which indicates the existence of intermittent structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970006691','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970006691"><span id="translatedtitle">Studies of Interstellar Pickup Ions in the <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Isenberg, Philip A.; Lee, Martin A.; Mobius, Eberhard</p> <p>1996-01-01</p> <p>The work under this grant involves studies of the interaction of interstellar pickup ions with the <span class="hlt">solar</span> <span class="hlt">wind</span>, with the goal of a comprehensive model of the particle distributions and wave intensities to be expected throughout the heliosphere, as well as the interactions of those distributions with the <span class="hlt">solar</span> <span class="hlt">wind</span> termination shock. In the past year, we have completed a number of projects, including observations and modeling of the effects of a large scattering mean free path on the pickup He(+) seen at AMPTE, an analytical model of anisotropic pickup tons in a steady radial magnetic field, and a derivation of a reduced <span class="hlt">solar</span> <span class="hlt">wind</span> Mach number due to increased estimates on the inflowing hydrogen density allowing for a weak termination shock. In the next year, we plan to investigate in more detail the correspondence between our models of anisotropic pickup ions and the data on spectra, variations, and proton-He(+) correlation provided by AMPTE, Ulysses, and our instrument on SOHO. We will model the time-dependent pickup ion density resulting from finite periods of radial magnetic field. We will also incorporate the effects of a large mean free path into our analysis of the He(+) focusing cone, leading to more accurate parameter values for the interstellar helium gas. This progress report also includes a discussion of our Space Physics Educational Outreach activities in the past year and plans for the next year.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20070005042&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bwaves','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20070005042&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bwaves"><span id="translatedtitle">Alfven Waves in the <span class="hlt">Solar</span> <span class="hlt">Wind</span>, Magnetosheath, and Outer Magnetosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sibeck, D. G.</p> <p>2007-01-01</p> <p>Alfven waves Propagating outward from the Sun are ubiquitous in the <span class="hlt">solar</span> <span class="hlt">wind</span> and play a major role in the <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere interaction. The passage of the waves generally occurs in the form of a series of discrete steepened discontinuities, each of which results in an abrupt change in the interplanetary magnetic field direction. Some orientations of the magnetic field permit particles energized at the Earth's bow shock to gain access to the foreshock region immediately upstream from the Earth's bow shock. The thermal pressure associated with these particles can greatly perturb <span class="hlt">solar</span> <span class="hlt">wind</span> plasma and magnetic field parameters shortly prior to their interaction with the Earth's bow shock and magnetosphere. The corresponding dynamic pressure variations batter the magnetosphere, driving magnetopause motion and transient compressions of the magnetospheric magnetic field. Alfven waves transmit information concerning the dynamic pressure variations applied to the magnetosphere to the ionosphere, where they generate the traveling convection vortices (TCVs) seen in high-latitude ground magnetograms. Finally, the sense of Alfvenic perturbations transmitted into the magnetosheath reverses across local noon because magnetosheath magnetic field lines drape against the magnetopause. The corresponding change in velocity perturbations must apply a weak torque to the Earth's magnetosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23368180','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23368180"><span id="translatedtitle">Construction of <span class="hlt">solar-wind</span>-like magnetic fields.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Roberts, D Aaron</p> <p>2012-12-01</p> <p>Fluctuations in the <span class="hlt">solar</span> <span class="hlt">wind</span> fields tend to not only have velocities and magnetic fields correlated in the sense consistent with Alfvén waves traveling from the Sun, but they also have the magnitude of the magnetic field remarkably constant despite their being broadband. This Letter provides, for the first time, a method for constructing fields with nearly constant magnetic field, zero divergence, and with any specified power spectrum for the fluctuations of the components of the field. Every wave vector, k, is associated with two polarizations; the relative phases of these can be chosen to minimize the variance of the field magnitude while retaining the "random" character of the fields. The method is applied to a case with one spatial coordinate that demonstrates good agreement with observed time series and power spectra of the magnetic field in the <span class="hlt">solar</span> <span class="hlt">wind</span>, as well as with the distribution of the angles of rapid changes ("discontinuities"), thus showing a deep connection between two seemingly unrelated issues. It is suggested that using this construction will lead to more realistic simulations of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence and of the propagation of energetic particles. PMID:23368180</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130012782','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130012782"><span id="translatedtitle">Construction of <span class="hlt">Solar-Wind</span>-Like Magnetic Fields</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Roberts, Dana Aaron</p> <p>2012-01-01</p> <p>Fluctuations in the <span class="hlt">solar</span> <span class="hlt">wind</span> fields tend to not only have velocities and magnetic fields correlated in the sense consistent with Alfven waves traveling from the Sun, but they also have the magnitude of the magnetic field remarkably constant despite their being broadband. This paper provides, for the first time, a method for constructing fields with nearly constant magnetic field, zero divergence, and with any specified power spectrum for the fluctuations of the components of the field. Every wave vector, k, is associated with two polarizations the relative phases of these can be chosen to minimize the variance of the field magnitude while retaining the\\random character of the fields. The method is applied to a case with one spatial coordinate that demonstrates good agreement with observed time series and power spectra of the magnetic field in the <span class="hlt">solar</span> <span class="hlt">wind</span>, as well as with the distribution of the angles of rapid changes (discontinuities), thus showing a deep connection between two seemingly unrelated issues. It is suggested that using this construction will lead to more realistic simulations of <span class="hlt">solar</span> <span class="hlt">wind</span> turbulence and of the propagation of energetic particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19770057048&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19770057048&hterms=wind+moon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwind%2Bmoon"><span id="translatedtitle">The <span class="hlt">solar</span> <span class="hlt">wind</span> and its influence on the atmospheres of moon, Mercury and Venus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hartle, R. E.</p> <p>1976-01-01</p> <p>The <span class="hlt">solar</span> <span class="hlt">wind</span> is expected to have an important influence on the atmospheres of the moon, Mercury and Venus and therefore a brief outline of <span class="hlt">solar</span> <span class="hlt">wind</span> theory is presented along with the predicted properties of the <span class="hlt">wind</span> at the orbits of these planets. Since the atmospheres of the moon and possibly Mercury are formed primarily by <span class="hlt">solar</span> <span class="hlt">wind</span> accretion, we present the latest accretion models for these bodies. The expected role the <span class="hlt">solar</span> <span class="hlt">wind</span> plays on both the ionization and termination of the ionosphere of Venus is discussed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSM41B2223D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSM41B2223D"><span id="translatedtitle">WSA-ENLIL Cone Extension: Improving <span class="hlt">Solar</span> <span class="hlt">Wind</span> Forcing Parameter Estimates at Mercury</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dewey, R. M.; Baker, D. N.; Anderson, B. J.; Benna, M.; Johnson, C. L.; Korth, H.; Gershman, D. J.; Ho, G. C.; McClintock, W. E.; Odstrcil, D.; Raines, J. M.; Schriver, D.; Slavin, J. A.; Solomon, S. C.; Winslow, R. M.; Zurbuchen, T.</p> <p>2013-12-01</p> <p>Understanding magnetospheric and exospheric processes at Mercury requires knowledge of <span class="hlt">solar</span> <span class="hlt">wind</span> 'forcing' conditions. This forcing includes both the background quasi-steady <span class="hlt">solar</span> <span class="hlt">wind</span> and the effects of transient <span class="hlt">solar</span> eruptions, most notably coronal mass ejections (CMEs). The departures from background <span class="hlt">solar</span> <span class="hlt">wind</span> due to CMEs often correspond to more than an order of magnitude greater ram pressure and dynamo electric field applied to the magnetosphere. Observations from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft were previously combined with the Wang-Sheeley-Arge (WSA)-ENLIL <span class="hlt">solar-wind</span> modeling tool to calculate such <span class="hlt">solar</span> <span class="hlt">wind</span> forcing parameters as the interplanetary magnetic field (IMF) strength (B); <span class="hlt">solar</span> <span class="hlt">wind</span> velocity (V), density (n), and temperature (T); ram pressure (~nV2); cross-magnetosphere electric field (V×B); and Alfvén Mach number (MA). Previous efforts relied only on the background <span class="hlt">solar</span> <span class="hlt">wind</span>, however, and constituted an incomplete model of <span class="hlt">solar</span> <span class="hlt">wind</span> forcing given that the effects of transient <span class="hlt">solar</span> phenomena were not included. The WSA-ENLIL model with the Cone extension permits inclusion of the effects of CMEs and related transient <span class="hlt">solar</span> phenomena, and thus characterization of the effect of strong <span class="hlt">solar</span> <span class="hlt">wind</span> perturbations on the Mercury system. The Cone extension utilizes the heliocentric location, velocity, and radial size of a CME to propagate it through the inner <span class="hlt">solar</span> system under the assumption of constant angular and radial velocity. This more complete approach provides a firmer basis with which to study magnetospheric and exospheric processes at Mercury and thereby better understand how the <span class="hlt">solar</span> <span class="hlt">wind</span> drives the Mercury system. Comparisons of WSA-ENLIL-Cone model outputs with measured properties from the MESSENGER Magnetometer (MAG), Neutron Spectrometer (NS), and Energetic Particle and Plasma Spectrometer (EPPS) permit quantification of the improvement in <span class="hlt">solar</span> <span class="hlt">wind</span>/IMF specification, particularly during times of the largest <span class="hlt">solar</span> eruptive events over the period 2011-2013.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19820047464&hterms=Collards&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DCollards','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19820047464&hterms=Collards&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DCollards"><span id="translatedtitle">Radial variation of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed between 1 and 15 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Collard, H. R.; Mihalov, J. D.; Wolfe, J. H.</p> <p>1982-01-01</p> <p>Pioneer 10 and 11 <span class="hlt">solar</span> <span class="hlt">wind</span> speeds measured between 1.4 and 15.2 AU are compared with those of IMP 6, 7, and 8 measured at 1 AU for 90-day intervals centered on six <span class="hlt">solar</span> radial alignments between 1973 and 1978. The time profile of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed undergoes change as the distance from the sun increases, which is due to interaction of adjacent <span class="hlt">solar</span> <span class="hlt">wind</span> streams. Speed variations are smaller at greater radial distance and both the highest and lowest speeds disappear as radial distance increases. For periods with extremely high speed <span class="hlt">solar</span> <span class="hlt">wind</span> streams, the mean <span class="hlt">solar</span> <span class="hlt">wind</span> speed decreases as the distance from the sun increases, which must be due to the disappearance of the highest speeds of the streams with increasing distance. It is concluded that at distances from the sun greater than 30-40 AU, the <span class="hlt">solar</span> <span class="hlt">wind</span> behavior may closely resemble that of a radially expanding constant speed plasma.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20150010745&hterms=Magnetics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DMagnetics','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20150010745&hterms=Magnetics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DMagnetics"><span id="translatedtitle">Anisotropic <span class="hlt">Solar</span> <span class="hlt">Wind</span> Sputtering of the Lunar Surface Induced by Crustal Magnetic Anomalies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Poppe, A. R.; Sarantos, M.; Halekas, J. S.; Delory, G. T.; Saito, Y.; Nishino, M.</p> <p>2014-01-01</p> <p>The lunar exosphere is generated by several processes each of which generates neutral distributions with different spatial and temporal variability. <span class="hlt">Solar</span> <span class="hlt">wind</span> sputtering of the lunar surface is a major process for many regolith-derived species and typically generates neutral distributions with a cosine dependence on <span class="hlt">solar</span> zenith angle. Complicating this picture are remanent crustal magnetic anomalies on the lunar surface, which decelerate and partially reflect the <span class="hlt">solar</span> <span class="hlt">wind</span> before it strikes the surface. We use Kaguya maps of <span class="hlt">solar</span> <span class="hlt">wind</span> reflection efficiencies, Lunar Prospector maps of crustal field strengths, and published neutral sputtering yields to calculate anisotropic <span class="hlt">solar</span> <span class="hlt">wind</span> sputtering maps. We feed these maps to a Monte Carlo neutral exospheric model to explore three-dimensional exospheric anisotropies and find that significant anisotropies should be present in the neutral exosphere depending on selenographic location and <span class="hlt">solar</span> <span class="hlt">wind</span> conditions. Better understanding of <span class="hlt">solar</span> <span class="hlt">wind</span>/crustal anomaly interactions could potentially improve our results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.math.uwaterloo.ca/~hdesterc/websiteW/Data/publications/journal/2001SpaceSciRev.pdf','EPRINT'); return false;" href="http://www.math.uwaterloo.ca/~hdesterc/websiteW/Data/publications/journal/2001SpaceSciRev.pdf"><span id="translatedtitle">A SURVEY OF FIELD-ALIGNED MACH NUMBER AND PLASMA BETA IN THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>De Sterck, Hans</p> <p></p> <p>A SURVEY OF FIELD-ALIGNED MACH NUMBER AND PLASMA BETA IN THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> JOHAN DE KEYSER and MICHEL Katholieke Universiteit Leuven, Leuven, Belgium Abstract. We have surveyed <span class="hlt">solar</span> <span class="hlt">wind</span> plasma beta and field-aligned Alfvénic Mach number using Ulysses and <span class="hlt">Wind</span> data. We show the characteristic timescale and occurrence</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www-ssc.igpp.ucla.edu/personnel/russell/papers/solwind_interact_magsphere_tutorial.pdf','EPRINT'); return false;" href="http://www-ssc.igpp.ucla.edu/personnel/russell/papers/solwind_interact_magsphere_tutorial.pdf"><span id="translatedtitle">The <span class="hlt">Solar</span> <span class="hlt">Wind</span> Interaction with the Earth's Magnetosphere: A Tutorial C. T. Russell</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Russell, Christopher T.</p> <p></p> <p>The <span class="hlt">Solar</span> <span class="hlt">Wind</span> Interaction with the Earth's Magnetosphere: A Tutorial C. T. Russell Department <span class="hlt">wind</span> dynamic pressure and the pressure exerted by the magnetosphere, principally that of its magnetic field. The shape of the magnetosphere is additionally influenced by the drag of the <span class="hlt">solar</span> <span class="hlt">wind</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www2.gi.alaska.edu/~chungsangng/JGR2010-solar-wind.pdf','EPRINT'); return false;" href="http://www2.gi.alaska.edu/~chungsangng/JGR2010-solar-wind.pdf"><span id="translatedtitle">Kolmogorov versus IroshnikovKraichnan spectra: Consequences for ion heating in the <span class="hlt">solar</span> <span class="hlt">wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Ng, Chung-Sang</p> <p></p> <p>heating in the <span class="hlt">solar</span> <span class="hlt">wind</span> C. S. Ng,1 A. Bhattacharjee,2 D. Munsi,2 P. A. Isenberg,2 and C. W. Smith2 <span class="hlt">wind</span> provides a quantitative, if indirect, observational constraint on the relevant phenomenology. Recently, a <span class="hlt">solar</span> <span class="hlt">wind</span> heating model based on Kolmogorov spectral scaling has produced reasonably good</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=273864','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=273864"><span id="translatedtitle">Analysis of off-grid hybrid <span class="hlt">wind</span> turbine/<span class="hlt">solar</span> PV water pumping systems</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>While many remote water pumping systems exist (e.g. mechanical windmills, <span class="hlt">solar</span> photovoltaic , <span class="hlt">wind</span>-electric, diesel powered), very few combine both the <span class="hlt">wind</span> and <span class="hlt">solar</span> energy resources to possibly improve the reliability and the performance of the system. In this paper, off-grid <span class="hlt">wind</span> turbine (WT) a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.math.waikato.ac.nz/~seano/Oughton-papers/solar-wind/FormanEA-sw13.pdf','EPRINT'); return false;" href="http://www.math.waikato.ac.nz/~seano/Oughton-papers/solar-wind/FormanEA-sw13.pdf"><span id="translatedtitle">Scaling anisotropy of the power in parallel and perpendicular components of the <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Oughton, Sean</p> <p></p> <p>Scaling anisotropy of the power in parallel and perpendicular components of the <span class="hlt">solar</span> <span class="hlt">wind</span> magnetic of the Power in Parallel and Perpendicular Components of the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Magnetic Field Miriam A. Forman1 ZLWK GLVWDQFH IURP WKH 6XQ 7KLV GDWD LQFOXGHV WKH VRlar <span class="hlt">wind</span> whose total power (Pxx + Pyy + Pzz#12; LQ</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5424208','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5424208"><span id="translatedtitle">A self-contained weather station for <span class="hlt">wind</span> and <span class="hlt">solar</span> energy prospecting</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Anderson, R.S.</p> <p>1982-08-01</p> <p>The collection of meteorological data for <span class="hlt">wind</span> and <span class="hlt">solar</span> energy studies has been facilitated through the development of electronic weather stations. The Weather Wizard is a microprocessor controlled weather station which can be programmed for specialized applications such as <span class="hlt">wind</span> and <span class="hlt">solar</span> energy resource assessment. Use of the Weather Wizard during a recent <span class="hlt">wind</span> energy related project is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://earthweb.ess.washington.edu/eharnett/papers/thesis.pdf','EPRINT'); return false;" href="http://earthweb.ess.washington.edu/eharnett/papers/thesis.pdf"><span id="translatedtitle">Fluid and Particle simulations of the Interaction of the <span class="hlt">Solar</span> <span class="hlt">Wind</span> with Magnetic Anomalies</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Harnett , Erika</p> <p></p> <p>simulations of the Interaction of the <span class="hlt">Solar</span> <span class="hlt">Wind</span> with Magnetic Anomalies on the Surface of the Moon and Mars Simulations of the <span class="hlt">solar</span> <span class="hlt">wind</span> interacting with the Moon and Mars indicate that the presence of magnetic <span class="hlt">wind</span> access to the surface of the Moon, suggesting that the regions of surface magnetization may</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2010-09-27/pdf/2010-24064.pdf','FEDREG'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2010-09-27/pdf/2010-24064.pdf"><span id="translatedtitle">75 FR 59291 - In the Matter of: Certain <span class="hlt">Wind</span> and <span class="hlt">Solar</span>-Powered Light Posts and Street Lamps; Notice of...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2010-09-27</p> <p>...Matter of: Certain <span class="hlt">Wind</span> and <span class="hlt">Solar</span>-Powered Light Posts and Street Lamps; Notice of Investigation...importation of certain <span class="hlt">wind</span> and <span class="hlt">solar</span>-powered light posts and street lamps by reason of infringement...and <span class="hlt">solar</span>- [[Page 59292</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUSMSH42B..02J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUSMSH42B..02J"><span id="translatedtitle">Heliospheric <span class="hlt">Solar</span> <span class="hlt">Wind</span> Parameter Forecasting Using Interplanetary Scintillation (IPS) Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jackson, B. V.; Hick, P.; Buffington, A.; Yu, H.; Mejia-Ambriz, J. C.; Luckett, N.; Bisi, M. M.</p> <p>2013-05-01</p> <p>At the University of California, San Diego (UCSD), remote-sensing analyses of the inner heliosphere have been regularly carried out using radio interplanetary scintillation (IPS) data for almost two decades employing data from the <span class="hlt">Solar</span>-Terrestrial Environment Laboratory (STELab), Japan, IPS arrays. More recently, several other world locations have planned to join in this effort in order to provide more complete coverage at times other than those above the celestial meridian of the observing station. These analyses have measured and reconstructed three-dimensional (3D) <span class="hlt">solar</span> <span class="hlt">wind</span> structure throughout the time period when data are available. This enables a real-time forecast of <span class="hlt">solar</span> <span class="hlt">wind</span> density and velocity outward from the observations that is nearly complete over the whole heliosphere with a time cadence of about one day. When using the IPS velocity analyses, we can accurately convect outwards the <span class="hlt">solar</span> surface background magnetic fields and thus can provide values of the field (radial and tangential components) throughout the global volume. In the inner heliosphere the results of these 3D analyses of density, velocity, and vector magnetic field have been forecast and compared successfully with in-situ measurements obtained near Earth, at STEREO, at Mars, at Venus, at MESSENGER, and at the Ulysses spacecraft. The resulting precise time-dependent results can also be used to provide an inner boundary of these parameters that can be further extrapolated outward to the edge of the heliosphere using current 3D-MHD modeling techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19960021443&hterms=solar+term&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bterm','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19960021443&hterms=solar+term&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Bterm"><span id="translatedtitle">Long term variability of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gazis, P. R.; Ahluwalia, H. S.; Fikani, M. M.; Xue, S. .S.</p> <p>1995-01-01</p> <p>We have reviewed the <span class="hlt">solar</span> <span class="hlt">wind</span> data obtained over a period of more than three decades. The data coverage on the Omnitape begins on 27 November 1963 and ends on 31 December 1993, for the version used by us. The coverage is very uneven, ranging from less than 40% to greater than 80%. We find that a correlation continues to exist between the measured values of the <span class="hlt">solar</span> <span class="hlt">wind</span> speed (V) and the geomagnetic index Ap. For the period when the coverage is greater than or equal to 85%, the data fit the equation: V (km/s) = 11.7 A(sub p) + 260. The correlation coefficient is 0.8, at a confidence level of 99.95%. However, we find that the predicted value of V may differ from the observed value by as much as 15% for a year in which the coverage is poorer. A comparison of IMP 8 with Pioneer Venus Orbiter (PVO) data indicates that the average values at the former are systematically higher by as much as 35 km/s (approximately 8%) for an overlapping time period. Also, we draw attention to the observed three <span class="hlt">solar</span> cycle periodicity in A(sub p) data for the 1932 to 1994 period and its implications for forecasting the parameters for <span class="hlt">solar</span> cycle 23 as well as on the computations of the modulation parameters for cosmic rays.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140017817','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140017817"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> Strahl Broadening by Self-Generated Plasma Waves</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pavan, J.; Vinas, A. F.; Yoon, P. H.; Ziebell, L. F.; Gaelzer, R.</p> <p>2013-01-01</p> <p>This Letter reports on the results of numerical simulations which may provide a possible explanation for the strahl broadening during quiet <span class="hlt">solar</span> conditions. The relevant processes involved in the broadening are due to kinetic quasi-linear wave-particle interaction. Making use of static analytical electron distribution in an inhomogeneous field, it is found that self-generated electrostatic waves at the plasma frequency, i.e., Langmuir waves, are capable of scattering the strahl component, resulting in energy and pitch-angle diffusion that broadens its velocity distribution significantly. The present theoretical results provide an alternative or complementary explanation to the usual whistler diffusion scenario, suggesting that self-induced electrostatic waves at the plasma frequency might play a key role in broadening the <span class="hlt">solar</span> <span class="hlt">wind</span> strahl during quiet <span class="hlt">solar</span> conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22118811','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22118811"><span id="translatedtitle"><span class="hlt">SOLAR</span> <span class="hlt">WIND</span> STRAHL BROADENING BY SELF-GENERATED PLASMA WAVES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pavan, J.; Gaelzer, R.; Vinas, A. F.; Yoon, P. H.; Ziebell, L. F. E-mail: rudi@ufpel.edu.br E-mail: yoonp@umd.edu</p> <p>2013-06-01</p> <p>This Letter reports on the results of numerical simulations which may provide a possible explanation for the strahl broadening during quiet <span class="hlt">solar</span> conditions. The relevant processes involved in the broadening are due to kinetic quasi-linear wave-particle interaction. Making use of static analytical electron distribution in an inhomogeneous field, it is found that self-generated electrostatic waves at the plasma frequency, i.e., Langmuir waves, are capable of scattering the strahl component, resulting in energy and pitch-angle diffusion that broadens its velocity distribution significantly. The present theoretical results provide an alternative or complementary explanation to the usual whistler diffusion scenario, suggesting that self-induced electrostatic waves at the plasma frequency might play a key role in broadening the <span class="hlt">solar</span> <span class="hlt">wind</span> strahl during quiet <span class="hlt">solar</span> conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19770033168&hterms=G3&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DG3','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19770033168&hterms=G3&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DG3"><span id="translatedtitle">Magnetic acceleration of <span class="hlt">winds</span> from <span class="hlt">solar</span>-type stars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Belcher, J. W.; Macgregor, K. B.</p> <p>1976-01-01</p> <p>The spin-down of <span class="hlt">solar</span> type stars (F5 V to G3 V) is generally ascribed to the outflow of magnetized plasma in the form of a <span class="hlt">wind</span>. Magnetically coupled stellar <span class="hlt">winds</span> are thought to provide the dominant mechanism for angular momentum loss over the entire main-sequence lifetime of stars possessing hydrogen convective zones. The associated loss in rotational kinetic energy can strongly affect the energetics of <span class="hlt">winds</span> emanating from such stars, for sufficiently high rotation rates and magnetic field strengths. In the present paper, an attempt is made to describe qualitatively how MHD plasma outflow from a rotating star adjusts itself to a broad range of stellar conditions, including fast, intermediate, and slow magnetic rotator configurations. Using the Weber and Davis (1967) model of MHD <span class="hlt">winds</span>, it is shown that the magnetic deceleration of an MHD <span class="hlt">wind</span> is of importance when the loss of rotational kinetic energy due to magnetic braking exceeds the energy flux due to thermal processes alone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.eiscat.rl.ac.uk/Members/mike/publications/pdfs/2010/262_Rouillard_2009JA014471.pdf','EPRINT'); return false;" href="http://www.eiscat.rl.ac.uk/Members/mike/publications/pdfs/2010/262_Rouillard_2009JA014471.pdf"><span id="translatedtitle">Intermittent release of transients in the slow <span class="hlt">solar</span> <span class="hlt">wind</span>: 1. Remote sensing observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lockwood, Mike</p> <p></p> <p>were first photographed by Annie Maunder in great detail during the 1898 <span class="hlt">solar</span> eclipse in IndiaClick Here for Full Article Intermittent release of transients in the slow <span class="hlt">solar</span> <span class="hlt">wind</span>: 1. Remote on board the STEREO spacecraft are used to analyze the <span class="hlt">solar</span> <span class="hlt">wind</span> during August and September 2007. We show</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2005_aj_540.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2005_aj_540.pdf"><span id="translatedtitle">ELECTRON HALO AND STRAHL FORMATION IN THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> BY RESONANT INTERACTION WITH WHISTLER WAVES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>ELECTRON HALO AND STRAHL FORMATION IN THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> BY RESONANT INTERACTION WITH WHISTLER WAVES C- trons in the <span class="hlt">solar</span> corona and <span class="hlt">wind</span>, including resonant interaction between electrons and whistler waves waves are assumed to be generated below the <span class="hlt">solar</span> coronal base and propagate through the corona</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2008_prl_051101.pdf','EPRINT'); return false;" href="http://sprg.ssl.berkeley.edu/adminstuff/webpubs/2008_prl_051101.pdf"><span id="translatedtitle">Eigenmode Structure in <span class="hlt">Solar-Wind</span> Langmuir Waves R. E. Ergun,1,2</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>California at Berkeley, University of</p> <p></p> <p>Eigenmode Structure in <span class="hlt">Solar-Wind</span> Langmuir Waves R. E. Ergun,1,2 D. M. Malaspina,2 Iver H. Cairns,3) We show that observed spatial- and frequency-domain signatures of intense <span class="hlt">solar-wind</span> Langmuir waves description of the growth, evolution, and mode conversion of Langmuir waves associated with <span class="hlt">solar</span> type II</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSH33A4127V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSH33A4127V"><span id="translatedtitle"><span class="hlt">Solar</span> <span class="hlt">Wind</span> C, N, and O Abundances and the <span class="hlt">Solar</span> Metallicity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>von Steiger, R.; Zurbuchen, T.; Shearer, P.; Gilbert, J. A.</p> <p>2014-12-01</p> <p><span class="hlt">Solar</span> <span class="hlt">wind</span> composition provides important constraints to <span class="hlt">solar</span> composition and to the processes that modify such compositional patterns in the atmospheres of the Sun and of active stars. There are a number of ways that composition can be observed, including spectroscopy, helioseismology, and the collection of <span class="hlt">solar</span> samples either in the form of <span class="hlt">solar</span> <span class="hlt">wind</span> or energetic particles. In either case, models are needed to infer compositional constraints from observations. For example, models are needed to interpret <span class="hlt">solar</span> spectroscopy results, and the evolution of these has recently led to significant changes to the previously accepted <span class="hlt">solar</span> composition. The collection of <span class="hlt">solar</span> samples requires a different type of consideration. Most <span class="hlt">solar</span> <span class="hlt">wind</span> and energetic particle samples are fractionated according to first ionization potential (FIP) as first pointed out by Hovestadt et al. in the seventies - elements with FIP below 10 eV are enhanced relative to elements at higher FIP, and He and possibly Ne are further depleted. Besides FIP fractionation there are indications from both isotopic and elemental data that mass fractionation, either through gravitational and/or collisional processes, may also play a role. Based on comparisons of in situ data with coronal spectroscopy it is evident that most of these processes occur at the interface between the photosphere and the corona. However, the high-latitude corona near <span class="hlt">solar</span> minimum appears to undergo much less fractionation, if any at all. Thus it provides a heliospheric sample that is - to within our observational constraints - photospheric in nature. The low-latitude heliosphere further provides direct access to plasmas that have the fractionation pattern qualitatively and quantitatively similar to the one observed in the corona. We present a recent reanalysis of the SWICS observations on both Ulysses and ACE using modern statistical tools. Concentrating on C, N, and O, which together with the recently published Ne (Shearer et al., ApJ, 2014) contribute 96% of the <span class="hlt">solar</span> metallicity, we find that the <span class="hlt">solar</span> <span class="hlt">wind</span> metallicity is significantly higher than the recent compilation of spectroscopic abundances (Asplund et al., ARAA, 2009). It is more in line with earlier spectroscopic results and, more importantly, not incompatible with helioseismology results of the <span class="hlt">solar</span> interior.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010Ge%26Ae..50..711L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010Ge%26Ae..50..711L"><span id="translatedtitle">Diagnostics of <span class="hlt">solar</span> <span class="hlt">wind</span> streams and their sources in the <span class="hlt">solar</span> corona</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lotova, N. A.; Vladimirskii, K. V.; Obridko, V. N.</p> <p>2010-12-01</p> <p>The studies are based on the experimental mass sounding of the interplanetary plasma near the Sun at radial distances of R = 4-70 R S, performed at Pushchino RAO, Russian Academy of Sciences, and on the calculated magnetic fields in the <span class="hlt">solar</span> corona based on the magnetic field strength and structure measured on the Sun's surface at J. Wilcox <span class="hlt">Solar</span> Observatory, United States. The experimental data make it possible to localize the position of the boundary closest to the Sun of the transition transonic region of the <span class="hlt">solar</span> <span class="hlt">wind</span> in the near-<span class="hlt">solar</span> space ( R ? 10-20 R S) and to perform an interrelated study of the <span class="hlt">solar</span> <span class="hlt">wind</span> structure and its sources, namely, the magnetic field components in the <span class="hlt">solar</span> corona based on these data. An analysis of the evolution of the flow types in 2000-2007 makes it possible to formulate the physically justified criterion responsible for the time boundaries of different epochs in the <span class="hlt">solar</span> activity cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22020364','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22020364"><span id="translatedtitle">ON THE NATURE OF THE <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> FROM CORONAL PSEUDOSTREAMERS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, Y.-M.; Sheeley, N. R. J.R.; Grappin, R.; Robbrecht, E. E-mail: neil.sheeley@nrl.navy.mil E-mail: eva.robbrecht@oma.be</p> <p>2012-04-20</p> <p>Coronal pseudostreamers, which separate like-polarity coronal holes, do not have current sheet extensions, unlike the familiar helmet streamers that separate opposite-polarity holes. Both types of streamers taper into narrow plasma sheets that are maintained by continual interchange reconnection with the adjacent open magnetic field lines. White-light observations show that pseudostreamers do not emit plasma blobs; this important difference from helmet streamers is due to the convergence of like-polarity field lines above the X-point, which prevents the underlying loops from expanding outward and pinching off. The main component of the pseudostreamer <span class="hlt">wind</span> has the form of steady outflow along the open field lines rooted just inside the boundaries of the adjacent coronal holes. These flux tubes are characterized by very rapid expansion below the X-point, followed by reconvergence at greater heights. Analysis of an idealized pseudostreamer configuration shows that, as the separation between the underlying holes increases, the X-point rises and the expansion factor f{sub ss} at the source surface increases. In situ observations of pseudostreamer crossings indicate <span class="hlt">wind</span> speeds v ranging from {approx}350 to {approx}550 km s{sup -1}, with O{sup 7+}/O{sup 6+} ratios that are enhanced compared with those in high-speed streams but substantially lower than in the slow <span class="hlt">solar</span> <span class="hlt">wind</span>. Hydrodynamic energy-balance models show that the empirical v-f{sub ss} relation overestimates the <span class="hlt">wind</span> speeds from nonmonotonically expanding flux tubes, particularly when the X-point is located at low heights and f{sub ss} is small. We conclude that pseudostreamers produce a 'hybrid' type of outflow that is intermediate between classical slow and fast <span class="hlt">solar</span> <span class="hlt">wind</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/266942','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/266942"><span id="translatedtitle">Helium abundance variations in the <span class="hlt">solar</span> <span class="hlt">wind</span>: Observations from Ulysses</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Barraclough, B.L.; Gosling, J.T.; Mccomas, D.J.; Goldstein, B.E.</p> <p>1995-06-01</p> <p>The abundance of helium in the <span class="hlt">solar</span> <span class="hlt">wind</span> averages approximately 4% but has been observed to vary by more than two orders of magnitude from 0.1 to 30%. Physical processes responsible for this variability are still not clearly understood. Previous work has shown a correlation between low He abundance and coronal streamer plasma and between high He abundance and coronal mass ejections (CMEs). The authors now have out-of-ecliptic data on helium in the <span class="hlt">solar</span> <span class="hlt">wind</span> from the plasma experiment aboard Ulysses. Tentative results show that the average high-latitude helium concentration is comparable to the in-ecliptic value for the present phase of the <span class="hlt">solar</span> cycle, that excursions of the hour-averaged abundance very seldom fall outside the range 2.5 to 6.5%, and that there seems to be very little abundance enhancement associated with CMEs encountered at latitudes greater than 30 deg as opposed to the situation commonly encountered with in-ecliptic CMEs. In addition, preliminary observations of a single CME by both ISEE (in-ecliptic) and Ulysses (out-of-ecliptic) show a considerable He enhancement at ISEE with little or no perturbation of the average value at Ulysses` location. This paper will first present new results from the Ulysses mission up to the time of the meeting on the average abundance of helium in the <span class="hlt">solar</span> <span class="hlt">wind</span> as a function of spacecraft position, and will then focus on the out-of-ecliptic results including latitudinal abundance variations and observations of abundance enhancements (or lack thereof) in high-latitude CMEs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/0809.4645v1','EPRINT'); return false;" href="http://arxiv.org/pdf/0809.4645v1"><span id="translatedtitle">Radio Remote Sensing of the Corona and the <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Steven R. Spangler; Catherine A. Whiting</p> <p>2008-09-26</p> <p>Modern radio telescopes are extremely sensitive to plasma on the line of sight from a radio source to the antenna. Plasmas in the corona and <span class="hlt">solar</span> <span class="hlt">wind</span> produce measurable changes in the radio wave amplitude and phase, and the phase difference between wave fields of opposite circular polarization. Such measurements can be made of radio waves from spacecraft transmitters and extragalactic radio sources, using radio telescopes and spacecraft tracking antennas. Data have been taken at frequencies from about 80 MHz to 8000 MHz. Lower frequencies probe plasma at greater heliocentric distances. Analysis of these data yields information on the plasma density, density fluctuations, and plasma flow speeds in the corona and <span class="hlt">solar</span> <span class="hlt">wind</span>, and on the magnetic field in the <span class="hlt">solar</span> corona. This paper will concentrate on the information that can be obtained from measurements of Faraday rotation through the corona and inner <span class="hlt">solar</span> <span class="hlt">wind</span>. The magnitude of Faraday rotation is proportional to the line of sight integral of the plasma density and the line-of-sight component of the magnetic field. Faraday rotation provides an almost unique means of estimating the magnetic field in this part of space. This technique has contributed to measurement of the large scale coronal magnetic field, the properties of electromagnetic turbulence in the corona, possible detection of electrical currents in the corona, and probing of the internal structure of coronal mass ejections (CMEs). This paper concentrates on the search for small-scale coronal turbulence and remote sensing of the structure of CMEs. Future investigations with the Expanded Very Large Array (EVLA) or Murchison Widefield Array (MWA) could provide unique observational input on the astrophysics of CMEs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980169246','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980169246"><span id="translatedtitle">A Study of the Structure of the Source Region of the <span class="hlt">Solar</span> <span class="hlt">Wind</span> in Support of a <span class="hlt">Solar</span> Probe Mission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Habbal , Shadia R.</p> <p>1998-01-01</p> <p>Despite the richness of the information about the physical properties and the structure of the <span class="hlt">solar</span> <span class="hlt">wind</span> provided by the Ulysses and SOHO observations, fundamental questions regarding the nature of the coronal heating mechanisms, their source, and the manifestations of the fast and slow <span class="hlt">solar</span> <span class="hlt">wind</span>, still remain unanswered. The last unexplored frontier to establish the connection between the structure and dynamics of the <span class="hlt">solar</span> atmosphere, its extension into interplanetary space, and the mechanisms responsible for the evolution of the <span class="hlt">solar</span> <span class="hlt">wind</span>, is the corona between 1 and 30 R(sub s). A <span class="hlt">Solar</span> Probe mission offers an unprecedented opportunity to explore this frontier. The uniqueness of this mission stems from its trajectory in a plane perpendicular to the ecliptic which reaches within 9 R(sub s), of the <span class="hlt">solar</span> surface over the poles and 3 - 9 R(sub s), at the equator. With a complement of simultaneous in situ and remote sensing observations, this mission is destined to have a significant impact on our understanding of the fundamental processes that heat the corona and drive the <span class="hlt">solar</span> <span class="hlt">wind</span>. The <span class="hlt">Solar</span> Probe should be able to detect remnants and signatures of the processes which heat the corona and accelerate the <span class="hlt">solar</span> <span class="hlt">wind</span>. The primary objective of this proposal was to explore the structure of the different source regions of the <span class="hlt">solar</span> <span class="hlt">wind</span> through complementary observational and theoretical studies in support of a <span class="hlt">Solar</span> Probe mission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AnGeo..33..697P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AnGeo..33..697P"><span id="translatedtitle">The influence of <span class="hlt">solar</span> <span class="hlt">wind</span> variability on magnetospheric ULF wave power</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pokhotelov, D.; Rae, I. J.; Murphy, K. R.; Mann, I. R.</p> <p>2015-06-01</p> <p>Magnetospheric ultra-low frequency (ULF) oscillations in the Pc 4-5 frequency range play an important role in the dynamics of Earth's radiation belts, both by enhancing the radial diffusion through incoherent interactions and through the coherent drift-resonant interactions with trapped radiation belt electrons. The statistical distributions of magnetospheric ULF wave power are known to be strongly dependent on <span class="hlt">solar</span> <span class="hlt">wind</span> parameters such as <span class="hlt">solar</span> <span class="hlt">wind</span> speed and interplanetary magnetic field (IMF) orientation. Statistical characterisation of ULF wave power in the magnetosphere traditionally relies on average <span class="hlt">solar</span> <span class="hlt">wind</span>-IMF conditions over a specific time period. In this brief report, we perform an alternative characterisation of the <span class="hlt">solar</span> <span class="hlt">wind</span> influence on magnetospheric ULF wave activity through the characterisation of the <span class="hlt">solar</span> <span class="hlt">wind</span> driver by its variability using the standard deviation of <span class="hlt">solar</span> <span class="hlt">wind</span> parameters rather than a simple time average. We present a statistical study of nearly one <span class="hlt">solar</span> cycle (1996-2004) of geosynchronous observations of magnetic ULF wave power and find that there is significant variation in ULF wave powers as a function of the dynamic properties of the <span class="hlt">solar</span> <span class="hlt">wind</span>. In particular, we find that the variability in IMF vector, rather than variabilities in other parameters (<span class="hlt">solar</span> <span class="hlt">wind</span> density, bulk velocity and ion temperature), plays the strongest role in controlling geosynchronous ULF power. We conclude that, although time-averaged bulk properties of the <span class="hlt">solar</span> <span class="hlt">wind</span> are a key factor in driving ULF powers in the magnetosphere, the <span class="hlt">solar</span> <span class="hlt">wind</span> variability can be an important contributor as well. This highlights the potential importance of including <span class="hlt">solar</span> <span class="hlt">wind</span> variability especially in studies of ULF wave dynamics in order to assess the efficiency of <span class="hlt">solar</span> <span class="hlt">wind</span>-magnetosphere coupling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930049604&hterms=Solar+activity+solar+cycle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSolar%2Bactivity%2Bsolar%2Bcycle','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930049604&hterms=Solar+activity+solar+cycle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSolar%2Bactivity%2Bsolar%2Bcycle"><span id="translatedtitle">Concerning <span class="hlt">solar</span> sources for Cycle 22 <span class="hlt">solar</span> <span class="hlt">wind</span> activity in the heliosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mihalov, J. D.; Barnes, A.; Mcdonald, F. B.; Burkepile, J. T.; Hundhausen, A. J.</p> <p>1992-01-01</p> <p>Beginning in 1989, the active phase of the present <span class="hlt">solar</span> cycle became manifest in the outer heliosphere as large disturbances in <span class="hlt">solar</span> <span class="hlt">wind</span> velocity as observed by the Ames plasma analyzers aboard Pioneer 10 (46-50 AU heliocentric distance) and Pioneer 11 (about 28 AU). Inner heliospheric baseline plasma observations from the Pioneer Venus Orbiter (0.7 AU) and IMP 8 (1 AU) are useful for attempts to correlate <span class="hlt">solar</span> events with the outer heliospheric disturbances. With regard to the onset of activity at Pioneer 11, Pioneer Venus observations are pertinent, and some of these in turn correspond with CMEs (coronal mass ejections) observed in SMM coronagraph data. In particular, enhanced <span class="hlt">solar</span> <span class="hlt">wind</span> speeds observed at Pioneer Venus during December 1988 to February 1989 are associated with seven large <span class="hlt">solar</span> <span class="hlt">wind</span> shocks (or shock candidates); corresponding CMEs may be identified. Two of these seven shocks were identified as candidates for a precursor to the onset of the disturbances at Pioneer 11. At Pioneer 10 the disturbed period includes two large disturbances, associated with the passage of shocks. There are several candidate CMEs in the SMM observations, one of which may be associated with the second Pioneer 10 shock.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21796206','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21796206"><span id="translatedtitle">Alfvénic waves with sufficient energy to power the quiet <span class="hlt">solar</span> corona and fast <span class="hlt">solar</span> <span class="hlt">wind</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>McIntosh, Scott W; De Pontieu, Bart; Carlsson, Mats; Hansteen, Viggo; Boerner, Paul; Goossens, Marcel</p> <p>2011-07-28</p> <p>Energy is required to heat the outer <span class="hlt">solar</span> atmosphere to millions of degrees (refs 1, 2) and to accelerate the <span class="hlt">solar</span> <span class="hlt">wind</span> to hundreds of kilometres per second (refs 2-6). Alfvén waves (travelling oscillations of ions and magnetic field) have been invoked as a possible mechanism to transport magneto-convective energy upwards along the Sun's magnetic field lines into the corona. Previous observations of Alfvénic waves in the corona revealed amplitudes far too small (0.5?km?s(-1)) to supply the energy flux (100-200?W?m(-2)) required to drive the fast <span class="hlt">solar</span> <span class="hlt">wind</span> or balance the radiative losses of the quiet corona. Here we report observations of the transition region (between the chromosphere and the corona) and of the corona that reveal how Alfvénic motions permeate the dynamic and finely structured outer <span class="hlt">solar</span> atmosphere. The ubiquitous outward-propagating Alfvénic motions observed have amplitudes of the order of 20?km?s(-1) and periods of the order of 100-500?s throughout the quiescent atmosphere (compatible with recent investigations), and are energetic enough to accelerate the fast <span class="hlt">solar</span> <span class="hlt">wind</span> and heat the quiet corona. PMID:21796206</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1221389-depth-profiling-analysis-solar-wind-helium-collected-diamond-like-carbon-film-from-genesis','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1221389-depth-profiling-analysis-solar-wind-helium-collected-diamond-like-carbon-film-from-genesis"><span id="translatedtitle">Depth profiling analysis of <span class="hlt">solar</span> <span class="hlt">wind</span> helium collected in diamond-like carbon film from Genesis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Bajo, Ken-ichi; Olinger, Chad T.; Jurewicz, Amy J.G.; Burnett, Donald S.; Sakaguchi, Isao; Suzuki, Taku; Itose, Satoru; Ishihara, Morio; Uchino, Kiichiro; Wieler, Rainer; et al</p> <p>2015-10-01</p> <p>The distribution of <span class="hlt">solar-wind</span> ions in Genesis mission collectors, as determined by depth profiling analysis, constrains the physics of ion solid interactions involving the <span class="hlt">solar</span> <span class="hlt">wind</span>. Thus, they provide an experimental basis for revealing ancient <span class="hlt">solar</span> activities represented by <span class="hlt">solar-wind</span> implants in natural samples. We measured the first depth profile of ?He in a collector; the shallow implantation (peaking at more »is consistent with TRIM simulations using the observed ?He velocity distribution during the Genesis mission. It is therefore likely that all <span class="hlt">solar-wind</span> elements heavier than H are completely intact in this Genesis collector and, consequently, the <span class="hlt">solar</span> particle energy distributions for each element can be calculated from their depth profiles. Ancient <span class="hlt">solar</span> activities and space weathering of <span class="hlt">solar</span> system objects could be quantitatively reproduced by <span class="hlt">solar</span> particle implantation profiles.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19740010336&hterms=heavy+metals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dheavy%2Bmetals','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19740010336&hterms=heavy+metals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dheavy%2Bmetals"><span id="translatedtitle">Measurements of heavy <span class="hlt">solar</span> <span class="hlt">wind</span> and higher energy <span class="hlt">solar</span> particles during the Apollo 17 mission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walker, R. M.; Zinner, E.; Maurette, M.</p> <p>1973-01-01</p> <p>The lunar surface cosmic ray experiment, consisting of sets of mica, glass, plastic, and metal foil detectors, was successfully deployed on the Apollo 17 mission. One set of detectors was exposed directly to sunlight and another set was placed in shade. Preliminary scanning of the mica detectors shows the expected registration of heavy <span class="hlt">solar</span> <span class="hlt">wind</span> ions in the sample exposed directly to the sun. The initial results indicate a depletion of very-heavy <span class="hlt">solar</span> <span class="hlt">wind</span> ions. The effect is probably not real but is caused by scanning inefficiencies. Despite the lack of any pronounced <span class="hlt">solar</span> activity, energetic heavy particles with energies extending to 1 MeV/nucleon were observed. Equal track densities of approximately 6000 tracks/cm sq 0.5 microns in length were measured in mica samples exposed in both sunlight and shade.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://arxiv.org/pdf/astro-ph/0702205v1','EPRINT'); return false;" href="http://arxiv.org/pdf/astro-ph/0702205v1"><span id="translatedtitle">Alfven Waves and Turbulence in the <span class="hlt">Solar</span> Atmosphere and <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>A. Verdini; M. Velli</p> <p>2007-02-07</p> <p>We solve the problem of propagation and dissipation of Alfvenic turbulence in a model <span class="hlt">solar</span> atmosphere consisting of a static photosphere and chromosphere, transition region, and open corona and <span class="hlt">solar</span> <span class="hlt">wind</span>, using a phenomenological model for the turbulent dissipation based on wave reflection. We show that most of the dissipation for a given wave-frequency spectrum occurs in the lower corona, and the overall rms amplitude of the fluctuations evolves in a way consistent with observations. The frequency spectrum, for a Kolmogorov-like slope, is not found to change dramatically from the photosphere to the <span class="hlt">solar</span> <span class="hlt">wind</span>, however it does preserve signatures of transmission throughout the lower atmospheric layers, namely oscillations in the spectrum at high frequencies reminiscent of the resonances found in the linear case. These may disappear once more realistic couplings for the non-linear terms are introduced, or if time-dependent variability of the lower atmospheric layer is introduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20090002604&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bwaves','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20090002604&hterms=solar+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bwaves"><span id="translatedtitle">Alfven Waves and Turbulence in the <span class="hlt">Solar</span> Atmosphere and <span class="hlt">Solar</span> <span class="hlt">Wind</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Verdini, Andrea; Velli, Marco</p> <p>2007-01-01</p> <p>We solve the problem of propagation and dissipation of Alfvenic turbulence in a model <span class="hlt">solar</span> atmosphere consisting of a static photosphere and chromosphere, transition region, and open corona and <span class="hlt">solar</span> <span class="hlt">wind</span> using a phenomenological model for the turbulent dissipation based on wave reflection. We show that most of the dissipation for a given wave frequency spectrum occurs in the lower corona, and the overall rms amplitude of the fluctuations evolves in a way consistent with observations. The frequency spectrum for a Kolmogorov-like slope is not found to change dramatically from the photosphere to the <span class="hlt">solar</span> <span class="hlt">wind</span>; however, it does preserve signatures of transmission throughout the lower atmospheric layers, namely, oscillations in the spectrum at high frequencies reminiscent of the resonances found in the linear case. These may disappear once more realistic couplings for the nonlinear terms are introduced or if time-dependent variability of the lower atmospheric layer is introduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMSM12A..01L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMSM12A..01L"><span id="translatedtitle">On the Mythical Relation Between <span class="hlt">Solar</span> <span class="hlt">Wind</span> Speed and Radiation Belt Electrons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, X.; Temerin, M. A.; Baker, D. N.; Reeves, G. D.</p> <p>2011-12-01</p> <p>It has been known for decades that the passage of high-speed <span class="hlt">solar</span> <span class="hlt">wind</span> correlates well with enhancements of radiation belt electrons in the magnetosphere. However an examination of fifteen years of continuous <span class="hlt">solar</span> <span class="hlt">wind</span> measurements and the daily averaged MeV electron fluxes at geosynchronous orbit shows that geomagnetic activity driven by a southward orientation of the interplanetary magnetic field, IMF, is a necessary condition for the MeV electron enhancement and that high-speed <span class="hlt">solar</span> <span class="hlt">wind</span> alone is neither necessary nor sufficient for the MeV electron enhancement. The reason that high-speed <span class="hlt">solar</span> <span class="hlt">wind</span> is almost always associated with the enhancement of MeV electrons is mainly because high-speed <span class="hlt">solar</span> <span class="hlt">wind</span> almost always has some southward components of the IMF. However, a combination of a long lasting high-speed <span class="hlt">solar</span> <span class="hlt">wind</span> and a southward oriented IMF produce highest fluxes of MeV electrons at geosynchronous orbit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030011270','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030011270"><span id="translatedtitle">Intercalibration and Cross-Correlation of Ace and <span class="hlt">Wind</span> <span class="hlt">Solar</span> <span class="hlt">Wind</span> Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2003-01-01</p> <p>This report covers activities funded from October 1, 1998 through September 30, 2002. Two yearly status reports have been filed on this grant, and they are included as Appendix 1. The purpose of this grant was to compare ACE and <span class="hlt">Wind</span> <span class="hlt">solar</span> <span class="hlt">wind</span> parameters when the two spacecraft were near to one another and then to use the intercalibrated parameters to carry out scientific investigations. In September, 2001 a request for a one-year, no-cost extension until September 30, 2002 was submitted and approved. The statement of work for that extension included adjustment of ACE densities below <span class="hlt">wind</span> speeds of 350 km/s, a study of shock normal orientations using travel time delays between the two spacecraft, comparison of density jumps at shocks, and a study of temperature anisotropies and double streaming to see if such features evolved between the spacecraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/929597','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/929597"><span id="translatedtitle"><span class="hlt">Wind</span> Tunnel Tests of Parabolic Trough <span class="hlt">Solar</span> Collectors: March 2001--August 2003</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hosoya, N.; Peterka, J. A.; Gee, R. C.; Kearney, D.</p> <p>2008-05-01</p> <p>Conducted extensive <span class="hlt">wind</span>-tunnel tests on parabolic trough <span class="hlt">solar</span> collectors to determine practical <span class="hlt">wind</span> loads applicable to structural design for stress and deformation, and local component design for concentrator reflectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://dspace.mit.edu/handle/1721.1/95834','EPRINT'); return false;" href="http://dspace.mit.edu/handle/1721.1/95834"><span id="translatedtitle">TURBULENT HEATING OF THE DISTANT <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Isenberg, Philip A.</p> <p></p> <p>Previous models of <span class="hlt">solar</span> <span class="hlt">wind</span> heating by interstellar pickup proton-driven turbulence have assumed that the <span class="hlt">wind</span> speed is a constant in heliocentric radial position. However, the same pickup process, which is taken to ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1087208','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1087208"><span id="translatedtitle">Using <span class="hlt">Solar</span> Business Models to Expand the Distributed <span class="hlt">Wind</span> Market (Presentation)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Savage, S.</p> <p>2013-05-01</p> <p>This presentation to attendees at <span class="hlt">Wind</span> Powering America's All-States Summit in Chicago describes business models that were responsible for rapid growth in the <span class="hlt">solar</span> industry and that may be applicable to the distributed <span class="hlt">wind</span> industry as well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2013-03-29/pdf/2013-07225.pdf','FEDREG'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2013-03-29/pdf/2013-07225.pdf"><span id="translatedtitle">78 FR 19099 - Residential, Business, and <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Resource Leases on Indian Land</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2013-03-29</p> <p>...Part 162 RIN 1076-AE73 Residential, Business, and <span class="hlt">Wind</span> and <span class="hlt">Solar</span> Resource Leases on Indian Land AGENCY: Bureau of Indian...agricultural lease'' and clarifies two provisions for <span class="hlt">wind</span> energy evaluation leases (WEELs). DATES: This...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22011866','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22011866"><span id="translatedtitle">EVOLUTION OF THE RELATIONSHIPS BETWEEN HELIUM ABUNDANCE, MINOR ION CHARGE STATE, AND <span class="hlt">SOLAR</span> <span class="hlt">WIND</span> SPEED OVER THE <span class="hlt">SOLAR</span> CYCLE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kasper, J. C.; Stevens, M. L.; Korreck, K. E.; Maruca, B. A.; Kiefer, K. K.; Schwadron, N. A.; Lepri, S. T.</p> <p>2012-02-01</p> <p>The changing relationships between <span class="hlt">solar</span> <span class="hlt">wind</span> speed, helium abundance, and minor ion charge state are examined over <span class="hlt">solar</span> cycle 23. Observations of the abundance of helium relative to hydrogen (A{sub He} {identical_to} 100 Multiplication-Sign n{sub He}/n{sub H}) by the <span class="hlt">Wind</span> spacecraft are used to examine the dependence of A{sub He} on <span class="hlt">solar</span> <span class="hlt">wind</span> speed and <span class="hlt">solar</span> activity between 1994 and 2010. This work updates an earlier study of A{sub He} from 1994 to 2004 to include the recent extreme <span class="hlt">solar</span> minimum and broadly confirms our previous result that A{sub He} in slow <span class="hlt">wind</span> is strongly correlated with sunspot number, reaching its lowest values in each <span class="hlt">solar</span> minima. During the last minimum, as sunspot numbers reached their lowest levels in recent history, A{sub He} continued to decrease, falling to half the levels observed in slow <span class="hlt">wind</span> during the previous minimum and, for the first time observed, decreasing even in the fastest <span class="hlt">solar</span> <span class="hlt">wind</span>. We have also extended our previous analysis by adding measurements of the mean carbon and oxygen charge states observed with the Advanced Composition Explorer spacecraft since 1998. We find that as <span class="hlt">solar</span> activity decreased, the mean charge states of oxygen and carbon for <span class="hlt">solar</span> <span class="hlt">wind</span> of a given speed also fell, implying that the <span class="hlt">wind</span> was formed in cooler regions in the corona during the recent <span class="hlt">solar</span> minimum. The physical processes in the coronal responsible for establishing the mean charge state and speed of the <span class="hlt">solar</span> <span class="hlt">wind</span> have evolved with <span class="hlt">solar</span> activity and time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20080031666&hterms=wind+work+you&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwind%2Bwork%2Byou','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20080031666&hterms=wind+work+you&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwind%2Bwork%2Byou"><span id="translatedtitle">Demonstrations that the <span class="hlt">Solar</span> <span class="hlt">Wind</span> Is Not Accelerated by Waves</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Roberts, Aaron</p> <p>2008-01-01</p> <p>The present work uses both observations and theoretical considerations to show that hydromagnetic waves cannot produce the acceleration of the fast <span class="hlt">solar</span> <span class="hlt">wind</span> and the related heating of the open <span class="hlt">solar</span> corona. Waves do exist, and can play a role in the differential heating and acceleration of minor ions, but their amplitudes are not sufficient to power the <span class="hlt">wind</span>, as demonstrated by extrapolation of magnetic spectra from Helios and Ulysses observations. Dissipation mechanisms invoked to circumvent this conclusion cannot be effective for a variety of reasons. In particular, turbulence does not play a strong role in the corona as shown by both observations of coronal striations and theoretical considerations of line-tying to a nonturbulent photosphere, nonlocality of interactions, and the nature of the kinetic dissipation. In the absence of wave heating and acceleration, the chromosphere and transition region become the natural source of open coronal energization. We suggest a variant of the 'velocity filtration' approach in which the emergence and complex churning of the magnetic flux in the chromosphere and transition region continuously and ubiquitously produces the nonthermal distributions required. These particles are then released by magnetic carpet reconnection at a wide range of scales and produce the <span class="hlt">wind</span> as described in kinetic approaches. Since the carpet reconnection is not the main source of the energization of the plasma, there is no expectation of an observable release of energy in nanoflares.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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