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Sample records for bipolar outflow sources

  1. Magnetic field and spatial structure of bipolar outflow sources

    NASA Technical Reports Server (NTRS)

    Hodapp, Klaus-Werner

    1990-01-01

    Deep K band images of three bipolar outflow sources (Cep A, GL 490, and R Mon) are presented. The polarization of background or embedded stars close to these star-forming regions has been measured in the I band to determine the local projected magnetic field direction. For Cep A the outflow direction and the magnetic field are almost parallel as is the case for most bipolar outflow sources. This alignment is poorer in the case of R Mon while GL 490 is a peculiar case with the outflow direction almost perpendicular to the local magnetic field. No indication was found for a distortion of the magnetic field close to the collimating disks of the outflows.

  2. TRACING THE BIPOLAR OUTFLOW FROM ORION SOURCE I

    SciTech Connect

    Plambeck, R. L.; Wright, M. C. H.; Friedel, D. N.; Widicus Weaver, S. L.; Bolatto, A. D.; Pound, M. W.; Woody, D. P.; Lamb, J. W.; Scott, S. L.

    2009-10-10

    Using CARMA, we imaged the 87 GHz SiO v = 0 J = 2-1 line toward Orion-KL with 0.''45 angular resolution. The maps indicate that radio source I drives a bipolar outflow into the surrounding molecular cloud along a NE-SW axis, in agreement with the model of Greenhill et al. The extended high-velocity outflow from Orion-KL appears to be a continuation of this compact outflow. High-velocity gas extends farthest along a NW-SE axis, suggesting that the outflow direction changes on timescales of a few hundred years.

  3. Star formation and the nature of bipolar outflows

    NASA Technical Reports Server (NTRS)

    Shu, Frank H.; Ruden, Steven P.; Lada, Charles J.; Lizano, Susana

    1991-01-01

    This paper presents a simple physical model for the bipolar molecular outflows that frequently accompany star formation. The model forges an intrinsic link between the bipolar flow phenomenon and the process of star formation, and it helps to explain many of the systematics known for existing sources.

  4. A Well-Defined Bipolar Outflow Shell

    NASA Astrophysics Data System (ADS)

    Xie, Taoling; Goldsmith, Paul F.; Patel, Nimesh

    1992-12-01

    A well-defined "eggplant-shaped" thin shell is revealed in the Mon R2 central core region by CO and (13) CO J=1-0 maps obtained with QUARRY. This thin shell outlines the extended blue lobe of the massive bipolar outflow. The projected length and width of the shell are about 5.7 pc and 2.5 pc respectively, and the averaged projected thickness of the shell is ~ 0.3 pc. The shape of this shell can be satisfactorily accounted for quantitatively in terms of limb-brightening within the framework of the Shu et al shell model with radially directed wind, although the model seems to be oversimplified with respect to the complexity that our data reveal. The outflow shell's symmetry axis is estimated to be inclined by ~ 70(deg) with respect to the line of sight. We suggest that the coincident blue- and red-shifted emission and the bending of the red-shifted lobe are the result of the red-shifted shell being compressed, rather than having a second bipolar outflow aligned roughly perpendicular to the axis of the first bipolar outflow.

  5. Shocked molecular hydrogen in the bipolar outflow NGC 2071

    NASA Technical Reports Server (NTRS)

    Burton, Michael G.; Geballe, T. R.; Brand, P. W. J. L.

    1989-01-01

    Maps of the emission from the v = 1-0 S(1) line of molecular hydrogen in the bipolar outflow of NGC 2071 are presented. The line emission is shown to peak at six positions distributed irregularly along two lobes which are parallel to, but offset about 20 arcsec from, the lobes of the high-velocity CO-line emission. The energetics and composition of the high-velocity gas support a model in which the driving agent is a bipolar atomic wind which arises from the vicinity of the central IR sources and shocks the surrounding molecular cloud, evacuating a cavity within it.

  6. High resolution observations of the L1551 bipolar outflow

    NASA Technical Reports Server (NTRS)

    Snell, R.; Moriarty-Schieven, G.; Strom, S.; Schloerb, P.; Strom, K.; Grasdalen, G.

    1986-01-01

    The nearby dark cloud Lynds 1551 contains one of the closest examples of a well-collimated bipolar molecular outflow. This source has the largest angular size of any known outflow and was the first bipolar outflow to be detected. The outflow originates from a low-luminosity young stellar object, IRS-5. Optical and radio continuum observations show the presence of a highly collimated, ionized stellar wind orginating from close to IRS-5 and aligned with the molecular outflow. However, we have little information on the actual mechanism that generates the stellar wind and collimates it into opposed jets. The Very Large Array (VLA) observations indicate that the winds originate within 10(15) cm of IRS-5, unfortunately at a size scale difficult to resolve. For these reasons, observations of the structure and dynamics of the hypersonic molecular gas may provide valuable information on the origin and evolution of these outflows. In addition, the study of the impact of the outflowing gas on the surrounding molecular material is essential to understand the consequence these outflows have on the evolution and star formation history of the entire cloud. Moriarty-Schieven et al. (1986) obtained a oversampled map of the CO emission of a portion of both the blueshifted and redshifted outflows in LI551 using Five College Radio Astronomy Observatory 14 m telescope. The oversampled maps have been reconstructed to an effective angular resolution of 20 arcsec using a maximum entropy algorithm. A continuation of the study of Moriarty-Schieven et al. is presented. The entire L1551 outflow has now been mapped at 12 arcsec sampling requiring roughly 4000 spectra. This data has been constructed to 20 arcsec resolution to provide the first high resolution picture of the entire L1551 outflow. This new data has shown that the blueshifted lobe is more extended than previously thought and has expanded downstream sufficiently to break out of the dense molecular cloud, but the redshifted outflow

  7. Bipolar Molecular Outflows from High-Mass Protostars

    NASA Astrophysics Data System (ADS)

    Su, Yu-Nung; Zhang, Qizhou; Lim, Jeremy

    2004-03-01

    We report observations of the bipolar molecular outflows associated with the luminous (~2×104 Lsolar) far-IR sources IRAS 21519+5613 and IRAS 22506+5944, as well the dust and molecular gas condensations on which these outflows appear to be centered. The observations were made in 12CO, 13CO, C18O, and continuum at 3 mm with the BIMA array and in 12CO and 13CO with the NRAO 12 m telescope to recover extended emission filtered out by the interferometric array. We find that the outflow associated with each IRAS source shows a clear bipolar morphology in 12CO, with properties (i.e., total mass of order 10-100 Msolar, mass-outflow rate >~10-3 Msolar, dynamical timescale 104-105 yr, and energetics) comparable with those of other massive outflows associated with luminous young stellar objects. Each outflow appears to be centered on a dust and gas condensation with a mass of 200-300 Msolar, likely marking the location of the driving source. The outflow lobes of both sources are fully resolved along their major but not minor axes, and they have collimation factors that may be comparable with young low-mass stars. The mass-velocity diagrams of both outflows change in slope at a velocity of ~10 km s-1, suggesting that the high-velocity component (HVC) may drive the low-velocity component (LVC). Although the HVC of IRAS 21519+5613 shows evidence for deceleration, no such signature is seen in the HVC of IRAS 22506+5944. Neither HVC has a momentum supply rate sufficient to drive their corresponding LVCs, although it is possible that the HVC is more highly excited and hence its thrust underestimated. Like for other molecular outflows the primary driving agent cannot be ionized gas, leaving atomic gas as the other remaining candidate. Neither IRAS 21519+5613 nor IRAS 22506+5944 exhibits detectable free-free emission, which together with the observed properties of their molecular outflows and surrounding condensations make them credible candidates for high-mass protostars. The mass

  8. Bipolar Nuclear Outflow from the Seyfert 1 Galaxy NGC 5548

    NASA Astrophysics Data System (ADS)

    Wrobel, J. M.

    1994-12-01

    The S0/Sa galaxy NGC 5548 hosts a Seyfert 1 nucleus. Echo mapping of its broad optical-line-emitting region yields a radial extent R <~ 20 light days = (1)/(60) pc, or 70 h microarcseonds for H_0 = 100 h km s(-1) Mpc(-1) (Peterson 1993). Using data from larger radii, what boundary conditions can be imposed on the geometry and velocity field of the broad line region? R <~ 1400 h(-1) pc: Bipolar radio continuum lobes straddle a central radio component in NGC 5548. These lobes, which emit optically-thin synchrotron radiation with a 4-cm power of 10(21) h(-2) W Hz(-1) , trace bipolar outflow from the nucleus (Wilson & Ulvestad 1982; Wrobel 1994). R <~ 720 h(-1) pc: The radio lobes of NGC 5548 share the elongation position angle of the [OIII] narrow-line gas, with the broadest known line widths occuring NW of the nucleus at these radii (Wilson et al. 1989). This hints that some narrow-line gas receives additional mechanical energy from the bipolar outflow feeding the radio lobes, a situation analogous to the narrow-line superbubble in NGC 3079 (Veilleux et al. 1994). R <~ 10 h(-1) pc: Blueshifted absorption in the broad CIV lines proves that some gas is flowing out of the nucleus of NGC 5548, with observed speeds of 1200 km s(-1) relative to systemic (Shull & Sachs 1993). This absorption line outflow may have, or be able to achieve, a bipolar shape via the disk-focusing scheme proposed for NGC 3079 (Duric & Seaquist 1988; Veilleux et al. 1994).

  9. (abstract) A Test of the Theoretical Models of Bipolar Outflows: The Bipolar Outflow in Mon R2

    NASA Technical Reports Server (NTRS)

    Xie, Taoling; Goldsmith, Paul; Patel, Nimesh

    1993-01-01

    We report some results of a study of the massive bipolar outflow in the central region of the relatively nearby giant molecular cloud Monoceros R2. We make a quantative comparison of our results with the Shu et al. outflow model which incorporates a radially directed wind sweeping up the ambient material into a shell. We find that this simple model naturally explains the shape of this thin shell. Although Shu's model in its simplest form predicts with reasonable parameters too much mass at very small polar angles, as previously pointed out by Masson and Chernin, it provides a reasonable good fit to the mass distribution at larger polar angles. It is possible that this discrepancy is due to inhomogeneities of the ambient molecular gas which is not considered by the model. We also discuss the constraints imposed by these results on recent jet-driven outflow models.

  10. Coexisting conical bipolar and equatorial outflows from a high-mass protostar.

    PubMed

    Greenhill, L J; Gwinn, C R; Schwartz, C; Moran, J M; Diamond, P J

    1998-12-17

    The BN/KL region in the Orion molecular cloud is an archetype for the study of the formation of stars much more massive than the Sun. This region contains luminous young stars and protostars but, like most star-forming regions, is difficult to study in detail because of the obscuring effects of dust and gas. Our basic expectations are shaped to some extent by the present theoretical picture of star formation, the cornerstone of which is that protostars accrete gas from rotating equatorial disks and shed angular momentum by ejecting gas in bipolar outflows. The main source of the outflow in the BN/KL region may be an object known as radio source I, which is commonly believed to be surrounded by a rotating disk of molecular material. Here we report high-resolution observations of silicon monoxide (SiO) and water maser emission from the gas surrounding source I. We show that within 60 AU of the source (about the size of the Solar System), the region is dominated by a conical bipolar outflow, rather than the expected disk. A slower outflow, close to the equatorial plane of the protostellar system, extends to radii of 1,000 AU. PMID:9872312

  11. The bipolar outflow from the rotating carbon star, V Hydrae

    NASA Technical Reports Server (NTRS)

    Kahane, C.; Maizels, C.; Jura, M.

    1988-01-01

    A high-resolution optical spectrum of the mass-losing red giant carbon star, V Hya, has been obtained, and the (C-12)O (J = 1-0) millimeter emission in the circumstellar envelope around this star has been mapped. It is found that the CO emission is extended, clearly anisotropic and can be interpreted as the superposition of an isotropic emission with that of a bipolar flow. The optical spectrum of the photosphere suggests that this star is rotating with v sin i between 10 and 20 km/s. These data are interpreted, together, to suggest that the bipolar nature of the outflow results from the flattening of the star induced by its rapid rotation.

  12. A Micro-Molecular Bipolar Outflow from HL Tauri

    NASA Astrophysics Data System (ADS)

    Takami, Michihiro; Beck, Tracy L.; Pyo, Tae-Soo; McGregor, Peter; Davis, Christopher

    2007-11-01

    We present detailed geometry and kinematics of the inner outflow toward HL Tau observed using Near Infrared Integral Field Spectrograph (NIFS) at the Gemini-North 8 m Observatory. We analyzed H2 2.122 μm emission and [Fe II] 1.644 μm line emission as well as the adjacent continuum observed at a <0.2" resolution. The H2 emission shows (1) a bubble-like geometry to the northeast of the star, as briefly reported in the previous paper, and (2) faint emission in the southwest counterflow, which has been revealed through careful analysis. The emission on both sides of the star shows an arc 1.0" away from the star, exhibiting a bipolar symmetry. Different brightnesses and morphologies in the northeast and southwest flows are attributed to absorption and obscuration of the latter by a flattened envelope and a circumstellar disk. The H2 emission shows a remarkably different morphology from the collimated jet seen in [Fe II] emission. The positions of some features coincide with scattering continuum, indicating that these are associated with cavities in the dusty envelope. Such properties are similar to millimeter CO outflows, although the spatial scale of the H2 outflow in our image (~150 AU) is strikingly smaller than the millimeter outflows, which often extend over 1000-10000 AU scales. The position-velocity diagrams of the H2 and [Fe II] emission do not show any evidence for kinematic interaction between these flows. All results described above support the scenario that the jet is surrounded by an unseen wide-angled wind, which interacts with the ambient gas and produces the bipolar cavity and shocked H2 emission. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National

  13. A young bipolar outflow from IRAS15398-3359

    NASA Astrophysics Data System (ADS)

    Bjerkeli, Per; Jørgensen, Jes K.

    2015-08-01

    The Class 0 protostar IRAS 15398-3359 is located in the Lupus I cloud at a distance of 155 pc. The source is known to harbour a molecular outflow, but the region has not attracted much interest until recently. IRAS 15398 is known to show interesting chemical signatures and being one of the very nearby, young outflow sources makes it an excellent target for detailed studies of the gas kinematics of different species.We present observations of several molecular species, carried out with the Submillimeter Array and ALMA, towards the IRAS 15398 outflow. The analysis of CO emission show obvious signs of episodic mass ejections, with a dynamical time scale between the knots in the jet, of the order 100 years. This is consistent with recent ALMA results where luminosity outbursts are estimated to occur on similar time-scales. The physical properties of the outflow, such as mass, momentum, momentum rate, mechanical luminosity, kinetic energy and mass-loss rate are estimated at relatively low values. We argue that this source is of a very young age, possibly younger than ~1000 years. This is consistent with recent studies of the kinematics of the inner envelope/disk. The observed line profiles were compared to full 3D radiative transfer models of the source, constructed with the Line Modelling Engine (LIME). The observed line shapes can only be understood when considering several distinctly different physical components, viz. the outflow cavity, the infalling envelope and the surrounding cloud material. This allows us to put quantitative constraints on the kinematics of the material close to the central source.

  14. Impacts of pure shocks in the BHR71 bipolar outflow

    NASA Astrophysics Data System (ADS)

    Gusdorf, A.; Riquelme, D.; Anderl, S.; Eislöffel, J.; Codella, C.; Gómez-Ruiz, A. I.; Graf, U. U.; Kristensen, L. E.; Leurini, S.; Parise, B.; Requena-Torres, M. A.; Ricken, O.; Güsten, R.

    2015-03-01

    Context. During the formation of a star, material is ejected along powerful jets that impact the ambient material. This outflow regulates star formation by e.g. inducing turbulence and heating the surrounding gas. Understanding the associated shocks is therefore essential to the study of star formation. Aims: We present comparisons of shock models with CO, H2, and SiO observations in a "pure" shock position in the BHR71 bipolar outflow. These comparisons provide an insight into the shock and pre-shock characteristics, and allow us to understand the energetic and chemical feedback of star formation on Galactic scales. Methods: New CO (Jup = 16, 11, 7, 6, 4, 3) observations from the shocked regions with the SOFIA and APEX telescopes are presented and combined with earlier H2 and SiO data (from the Spitzer and APEX telescopes). The integrated intensities are compared to a grid of models that were obtained from a magneto-hydrodynamical shock code, which calculates the dynamical and chemical structure of these regions combined with a radiative transfer module based on the "large velocity gradient" approximation. Results: The CO emission leads us to update the conclusions of our previous shock analysis: pre-shock densities of 104 cm-3 and shock velocities around 20-25 km s-1 are still constrained, but older ages are inferred (~4000 years). Conclusions: We evaluate the contribution of shocks to the excitation of CO around forming stars. The SiO observations are compatible with a scenario where less than 4% of the pre-shock SiO belongs to the grain mantles. We infer outflow parameters: a mass of 1.8 × 10-2 M⊙ was measured in our beam, in which a momentum of 0.4 M⊙ km s-1 is dissipated, corresponding to an energy of 4.2 × 1043 erg. We analyse the energetics of the outflow species by species. Comparing our results with previous studies highlights their dependence on the method: H2 observations only are not sufficient to evaluate the mass of outflows.

  15. An infrared study of the bi-polar outflow region GGD 12-15

    NASA Technical Reports Server (NTRS)

    Harvey, P. M.; Wilking, B. A.; Joy, M.; Lester, D. F.

    1984-01-01

    Infrared observations from 1 to 100 microns are presented for the region associated with a bipolar CO outflow source near the nebulous objects GGD 12 to 15. A luminous far-infrared source was found associated with a radio-continuum source in the area. This object appears to be a compact HII region around a nearly main-sequence BO star. A faint 20 micron source was also discovered at the position of an H2O maser 3O deg northwest of the HII region. This object appears to be associated with but not coincident with a 2 micron reflection nebula. This structure serves as evidence for a non-spherically symmetric, possibly disk-like dust distribution around the exciting star for the maser. This object probably powers the bi-polar CO outflow although its luminosity is less than 10% that of the star which excites the compact HII region. A number of other 2 micron sources found in the area are probably members of a recently formed cluster.

  16. Multiwavelength Spectroscopy of the Bipolar Outflow from Cepheus E

    NASA Astrophysics Data System (ADS)

    Smith, Michael D.; Froebrich, Dirk; Eislöffel, Jochen

    2003-07-01

    Cepheus E is the site of an exceptional example of a protostellar outflow with a very young dynamical age and extremely high near-infrared luminosity. We combine molecular spectroscopic data from the submillimeter to the near-infrared in order to interpret the rotational excitation of CO and the rovibrational excitation of H2. We conclude that C-type shocks with a paraboloidal bow shock geometry can simultaneously explain all the molecular excitations. Extinction accounts for the deviation of the column densities from local thermodynamic equilibrium. A difference in the extinction between the red- and blueshifted outflow lobes may account for the measured flux difference. The outflow is deeply embedded in a clump of density 105 cm-3, yet a good fraction of atomic hydrogen, about 40%, is required to explain the excitation and statistical equilibrium. We propose that this atomic component arises, self-consistently, from the dissociated gas at the apex of the leading bow shocks and the relatively long molecule reformation time. At least 20 bow shocks are required in each lobe, although these may be subdivided into smaller bows and turbulent shocked regions. The total outflow mechanical power and cooling amounts to over 30 Lsolar, almost half the source's bolometric luminosity. Nevertheless, only about 6% of the clump mass has been set in outward motion by the outflow, allowing a collapse to continue. Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA.

  17. An Ordered Bipolar Outflow from a Massive Early-stage Core

    NASA Astrophysics Data System (ADS)

    Tan, Jonathan C.; Kong, Shuo; Zhang, Yichen; Fontani, Francesco; Caselli, Paola; Butler, Michael J.

    2016-04-01

    We present ALMA follow-up observations of two massive, early-stage core candidates, C1-N and C1-S, in IRDC G028.37+00.07, that were previously identified by their {{{N}}}2{{{D}}}+(3-2) emission, and show high levels of deuteration of this species. The cores are also dark at far-infrared wavelengths up to ∼ 100 μ {{m}}. We detect 12CO(2-1) from a narrow, highly collimated bipolar outflow that is being launched from near the center of the C1-S core, which is also the location of the peak 1.3 mm dust continuum emission. This protostar, C1-Sa, has associated dense gas traced by {{{C}}}18{{O}}(2-1) and DCN(3-2), from which we estimate that it has a radial velocity that is near the center of the range exhibited by the C1-S massive core. A second outflow-driving source is also detected within the projected boundary of C1-S, but it appears to be at a different radial velocity. After considering the properties of the outflows, we conclude that C1-Sa is a promising candidate for an early-stage massive protostar and as such it shows that these early phases of massive star formation can involve highly ordered outflow, and thus accretion, processes, similar to models developed to explain low-mass protostars.

  18. A young bipolar outflow from IRAS 15398-3359

    NASA Astrophysics Data System (ADS)

    Bjerkeli, P.; Jørgensen, J. K.; Brinch, C.

    2016-03-01

    Context. Changing physical conditions in the vicinity of protostars allow for a rich and interesting chemistry to occur. Heating and cooling of the gas allows molecules to be released from and frozen out on dust grains. These changes in physics, traced by chemistry as well as the kinematical information, allows us to distinguish between different scenarios describing the infall of matter and the launching of molecular outflows and jets. Aims: We aim to determine the spatial distribution of different species that are of different chemical origin. This is to examine the physical processes in play in the observed region. From the kinematical information of the emission lines we aim to determine the nature of the infalling and outflowing gas in the system. We also aim to determine the physical properties of the outflow. Methods: Maps from the Submillimeter Array (SMA) reveal the spatial distribution of the gaseous emission towards IRAS 15398-3359. The line radiative transfer code LIME is used to construct a full 3D model of the system taking all relevant components and scales into account. Results: CO, HCO+, and N2H+ are detected and shown to trace the motions of the outflow. For CO, the circumstellar envelope and the surrounding cloud also have a profound impact on the observed line profiles. N2H+ is detected in the outflow, but is suppressed towards the central region, perhaps because of the competing reaction between CO and H3+ in the densest regions as well as the destruction of N2H+ by CO. N2D+ is detected in a ridge south-west of the protostellar condensation and is not associated with the outflow. The morphology and kinematics of the CO emission suggests that the source is younger than ~1000 years. The mass, momentum, momentum rate, mechanical luminosity, kinetic energy, and mass-loss rate are also all estimated to be low. A full 3D radiative transfer model of the system can explain all the kinematical and morphological features in the system.

  19. DETECTION OF A BIPOLAR MOLECULAR OUTFLOW DRIVEN BY A CANDIDATE FIRST HYDROSTATIC CORE

    SciTech Connect

    Dunham, Michael M.; Chen Xuepeng; Arce, Hector G.; Bourke, Tyler L.; Schnee, Scott; Enoch, Melissa L.

    2011-11-20

    We present new 230 GHz Submillimeter Array observations of the candidate first hydrostatic core Per-Bolo 58. We report the detection of a 1.3 mm continuum source and a bipolar molecular outflow, both centered on the position of the candidate first hydrostatic core. The continuum detection has a total flux density of 26.6 {+-} 4.0 mJy, from which we calculate a total (gas and dust) mass of 0.11 {+-} 0.05 M{sub Sun} and a mean number density of 2.0 {+-} 1.6 Multiplication-Sign 10{sup 7} cm{sup -3}. There is some evidence for the existence of an unresolved component in the continuum detection, but longer-baseline observations are required in order to confirm the presence of this component and determine whether its origin lies in a circumstellar disk or in the dense inner envelope. The bipolar molecular outflow is observed along a nearly due east-west axis. The outflow is slow (characteristic velocity of 2.9 km s{sup -1}), shows a jet-like morphology (opening semi-angles {approx}8 Degree-Sign for both lobes), and extends to the edges of the primary beam. We calculate the kinematic and dynamic properties of the outflow in the standard manner and compare them to several other protostars and candidate first hydrostatic cores with similarly low luminosities. We discuss the evidence both in support of and against the possibility that Per-Bolo 58 is a first hydrostatic core, and we outline future work needed to further evaluate the evolutionary status of this object.

  20. Near-infrared polarization in the bipolar outflow OH 0739-14

    NASA Technical Reports Server (NTRS)

    Shure, Mark; Sellgren, K.; Jones, T. J.; Klebe, D.

    1995-01-01

    We present linear polarization observations of the bipolar outlfow source OH 0739-14 from 1.2 to 3.6 micrometers. The high levels of polarization (approximatly 47% in the bipolar lobes) and the angles of the vectors in the outflow lobes imply that the 1.2-3.6 micrometer polarization is due to single scattering by dust grains of light from the central source or from its immediate vicinity. Our polarization measurements, combined with phase-lag measurements of variability in the nebula by Kastner et al. (1992), tightly constrain the inclination angle i between the bipolar axis and the plane of the sky to be 35 deg less than or = i less than or = 37 deg. We observe the percentage polarization of the bipolar lobes to be constant with wavelength from 1.2 to 3.6 micrometers, which rules out any significant contribution by unpolarized emission, such as tiny grain emission, to the 3.6 micrometer emission. We propose to explain the K-L' color of the nebula as due to illumination by both the central star and by thermal emission from dust in a surrounding circumstellar shell with a dust temperature of 600-1000 K. Using this model, we find a relatively high minimum scattering optical depth at 3.75 micrometers of tau omega greater than 0.1. This is difficult to reconcile with Rayleigh scattering, which would then imply optically thick scattering at wavelengths of 1.2 and 1.65 micrometers, in constrast to the observations. We also find that the albedo of the grains at 3.75 micrometers and probably at 2.2 micrometers is higher than predicted for normal interstellar grains.

  1. SPITZER AND NEAR-INFRARED OBSERVATIONS OF A NEW BIPOLAR PROTOSTELLAR OUTFLOW IN THE ROSETTE MOLECULAR CLOUD

    SciTech Connect

    Ybarra, Jason E.; Lada, Elizabeth A.; Fleming, Scott W.; Balog, Zoltan; Phelps, Randy L.

    2010-05-01

    We present and discuss Spitzer and near-infrared H{sub 2} observations of a new bipolar protostellar outflow in the Rosette Molecular Cloud. The outflow is seen in all four InfraRed Array Camera (IRAC) bands and partially as diffuse emission in the MIPS 24 {mu}m band. An embedded MIPS 24 {mu}m source bisects the outflow and appears to be the driving source. This source is coincident with a dark patch seen in absorption in the 8 {mu}m IRAC image. Spitzer IRAC color analysis of the shocked emission was performed from which thermal and column density maps of the outflow were constructed. Narrowband near-infrared (NIR) images of the flow reveal H{sub 2} emission features coincident with the high temperature regions of the outflow. This outflow has now been given the designation MHO 1321 due to the detection of NIR H{sub 2} features. We use these data and maps to probe the physical conditions and structure of the flow.

  2. SPATIALLY RESOLVED OBSERVATIONS OF THE BIPOLAR OPTICAL OUTFLOW FROM THE BROWN DWARF 2MASS J12073347-3932540

    SciTech Connect

    Whelan, E. T.; Ray, T. P.; Comeron, F.; Bacciotti, F.; Kavanagh, P. J.

    2012-12-20

    Studies of brown dwarf (BD) outflows provide information pertinent to questions on BD formation, as well as allowing outflow mechanisms to be investigated at the lowest masses. Here new observations of the bipolar outflow from the 24 M{sub JUP} BD 2MASS J12073347-3932540 are presented. The outflow was originally identified through the spectro-astrometric analysis of the [O I]{lambda}6300 emission line. Follow-up observations consisting of spectra and [S II], R-band and I-band images were obtained. The new spectra confirm the original results and are used to constrain the outflow position angle (P.A.) at {approx}65 Degree-Sign . The [O I]{lambda}6300 emission line region is spatially resolved and the outflow is detected in the [S II] images. The detection is firstly in the form of an elongation of the point-spread function (PSF) along the direction of the outflow P.A. Four faint knot-like features (labeled A-D) are also observed to the southwest of 2MASS J12073347-3932540 along the same P.A. suggested by the spectra and the elongation in the PSF. Interestingly, D, the feature furthest from the source, is bow shaped with the apex pointing away from 2MASS J12073347-3932540. A color-color analysis allows us to conclude that at least feature D is part of the outflow under investigation while A is likely a star or galaxy. Follow-up observations are needed to confirm the origin of B and C. This is a first for a BD, as BD optical outflows have to date only been detected using spectro-astrometry. This result also demonstrates for the first time that BD outflows can be collimated and episodic.

  3. A Massive Bipolar Outflow and a Dusty Torus with Large Grains in the Preplanetary Nebula IRAS 22036+5306

    NASA Technical Reports Server (NTRS)

    Sahai, Raghvendra; Young, K.; Patel, N. A.; Sanchez Contreras, C.; Morris, M.

    2006-01-01

    We report high angular resolution (approx.1") CO J=3-2 interferometric mapping using the Submillimeter Array (SMA) of IRAS 22036+5306 (I22036), a bipolar preplanetary nebula (PPN) with knotty jets discovered in our HST snapshot survey of young PPNs. In addition, we have obtained supporting lower resolution (approx.10") CO and 13CO J=1-0 observations with the Owens Valley Radio Observatory (OVRO) interferometer, as well as optical long-slit echelle spectra at the Palomar Observatory. The CO J=3-2 observations show the presence of a very fast (approx.220 km/s), highly collimated, massive (0.03 Solar Mass) bipolar outflow with a very large scalar momentum (about 10(exp 39) g cm/s), and the characteristic spatiokinematic structure of bow shocks at the tips of this outflow. The H(alpha) line shows an absorption feature blueshifted from the systemic velocity by approx.100 km/s, which most likely arises in neutral interface material between the fast outflow and the dense walls of the bipolar lobes at low latitudes. The fast outflow in I22036, as in most PPNs, cannot be driven by radiation pressure. We find an unresolved source of submillimeter (and millimeter-wave) continuum emission in I22036, implying a very substantial mass (0.02-0.04 Solar Mass) of large (radius > or approx.1 mm), cold (< or approx.50 K) dust grains associated with I22036's toroidal waist. We also find that the C-13/C-12 ratio in I22036 is very high (0.16), close to the maximum value achieved in equilibrium CNO nucleosynthesis (0.33). The combination of the high circumstellar mass (i.e., in the extended dust shell and the torus) and the high C-13/C-12 ratio in I22036 provides strong support for this object having evolved from a massive (> or approx.4 Solar Mass) progenitor in which hot-bottom-burning has occurred.

  4. Spitzer And Near-infrared Observations Of A Bi-polar Outflow In The Rosette Molecular Cloud

    NASA Astrophysics Data System (ADS)

    Ybarra, Jason E.; Lada, E. A.; Balog, Z.; Fleming, S. W.; Phelps, R. L.

    2010-01-01

    We present and discuss Spitzer and near-infrared H2 observations of a bi-polar protostellar outflow in the Rosette Molecular Cloud. The outflow is seen in all four IRAC bands and partially in the MIP 24 micron band. A dark cloud seen in absorption in the 8 micron image bisects the outflow and contains an embedded Class 0 object that appears to be the outflow source. Near-infrared narrow-band H2 observations were obtained using the Infrared Side Port Imager (ISPI) on the CTIO 4 meter telescope. Spitzer IRAC color analysis of the shocked emission was performed from which thermal and density maps of the outflow were constructed. We use these data and maps to probe the physical conditions and structure of the flow. This work is based in part on archival data obtained with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by an award issued by JPL/Caltech, NASA LTSA Grant NNG05GD66G, and the Florida Space Grant Consortium

  5. Discovery of an Extremely Wide-angle Bipolar Outflow in AFGL 5142

    NASA Astrophysics Data System (ADS)

    Liu, Tie; Zhang, Qizhou; Kim, Kee-Tae; Wu, Yuefang; Lee, Chang-Won; Goldsmith, Paul F.; Li, Di; Liu, Sheng-Yuan; Chen, Huei-Ru; Tatematsu, Ken’ichi; Wang, Ke; Lee, Jeong-Eun; Qin, Sheng-Li; Mardones, Diego; Cho, Se-Hyung

    2016-06-01

    Most bipolar outflows are associated with individual young stellar objects and have small opening angles. Here we report the discovery of an extremely wide-angle (∼180°) bipolar outflow (“EWBO”) in a cluster forming region AFGL 5142 from low-velocity emission of the HCN (3–2) and HCO+ (3–2) lines. This bipolar outflow is along a north-west to south-east direction with a line of sight flow velocity of about 3 km s‑1 and is spatially connected to the high-velocity jet-like outflows. It seems to be a collection of low-velocity material entrained by the high-velocity outflows due to momentum feedback. The total ejected mass and mass loss rate due to both high-velocity jet-like outflows and the “EWBO” are ∼24.5 M ⊙ and ∼1.7 × 10‑3 M ⊙ yr‑1, respectively. Global collapse of the clump is revealed by the “blue profile” in the HCO+ (1–0) line. A hierarchical network of filaments was identified in NH3 (1, 1) emission. Clear velocity gradients of the order of 10 km s‑1 pc‑1 are found along filaments, indicating gas inflow along the filaments. The sum of the accretion rate along filaments and mass infall rate along the line of sight is ∼3.1 × 10‑3 M ⊙ yr‑1, which exceeds the total mass loss rate, indicating that the central cluster is probably still gaining mass. The central cluster is highly fragmented and 22 condensations are identified in 1.1 mm continuum emission. The fragmentation process seems to be determined by thermal pressure and turbulence. The magnetic field may not play an important role in fragmentation.

  6. Bipolar Outflow Offset from the Nucleus of M33

    NASA Astrophysics Data System (ADS)

    Roming, P. W. A.; Moody, J. W.; Hintz, M. L.; Wu, K.; Soria, R.

    2002-12-01

    Using long-slit spectra centered in wavelength about Hα , we have produced a velocity map of a 0.5' x 2' hourglass shaped object centered 38" southeast of the optical center of M33. The velocity resolution is 1.1 km/s. We have also produced electron temperature, electron density, and shock heating maps of the same region using the [NII](λ 6548), [NII](λ 6583), Hα , [SII](λ 6717), and [SII](λ 6731) lines. The data reveal that the gas is flowing away from the center of this hourglass shaped object and that the electron temperature and density of the region is relatively low. The shock heating maps indicate that very little of the gas in the region is shock heated. Using this new data and previously published UV, IR, and radio data we investigate possible scenarios that could explain this large scale, low velocity outflow.

  7. From bipolar to quadrupolar - The collimation processes of the Cepheus A outflow

    NASA Technical Reports Server (NTRS)

    Torrelles, Jose M.; Verdes-Montenegro, Lourdes; Ho, Paul T. P.; Rodriguez, Luis F.; Canto, Jorge

    1993-01-01

    Results of new K-band observations of the (1, 1) and (2, 2) ammonia lines toward Cepheus A are reported. The lines are mapped with approximately 2 arcsec of angular resolution and 0.3 km/s of velocity resolution. A sensitivity of 10 mJy has been achieved. The observations reveal details of the spatial and kinematics structure of the ambient high-density gas. It is suggested that the interstellar high-density gas is diverting and redirecting the outflow in the sense that the quadrupolar structure of the molecular outflow is produced by the interaction with the ammonia condensationss, with Cep A-1 and Cep A-3 splitting in two halves, respectively the blue- and redshifted lobes of an east-west bipolar molecular outflow.

  8. HH 588: A giant bipolar outflow in the dark cloud BRC 37

    NASA Astrophysics Data System (ADS)

    Movsessian, T. A.; Magakian, T. Yu.; Sargsyan, D. M.; Ogura, K.

    2012-12-01

    Results of 2D spectroscopy of the complex of Herbig-Haro objects HH 588 in the dark globule BRC 37 are presented. The multipupil spectrograph VAGR has been used to obtain spectra of four parts of this complex, including the objects NE2, NE1, center, and SW2. The kinematic characteristics of these components of the complex confirm the existence of a giant bipolar outflow from the central infrared source IRAS 21388+5622. Spectral studies also show that the central object has the very low excitation and strong [OI] and [SII] emission characteristic of jets emerging from young stellar objects. In terms of their physical parameters, the other objects are typical Herbig-Haro objects. On the other hand, it is found that the entire HH 588 complex is an irradiated Herbig-Haro flow. This is indicated by the comparatively high excitation of the object NE2, and by the fact that the entire HH 588 flow is an arc with its convex side facing the center of the HII region IC 1396.

  9. IONIZED OUTFLOWS FROM COMPACT STEEP SPECTRUM SOURCES

    SciTech Connect

    Shih, Hsin-Yi; Stockton, Alan; Kewley, Lisa E-mail: stockton@ifa.hawaii.edu

    2013-08-01

    Massive outflows are known to exist, in the form of extended emission-line regions (EELRs), around about one-third of powerful FR II radio sources. We investigate the origin of these EELRs by studying the emission-line regions around compact-steep-spectrum (CSS) radio galaxies that are younger (10{sup 3}-10{sup 5} yr old) versions of the FR II radio galaxies. We have searched for and analyzed the emission-line regions around 11 CSS sources by taking integral field spectra using Gemini Multi-Object Spectrograph on Gemini North. We fit the [O III] {lambda}5007 line and present the velocity maps for each detected emission-line region. We find, in most cases, that the emission-line regions have multi-component velocity structures with different velocity dispersions and/or flux distributions for each component. The velocity gradients of the emission-line gas are mostly well aligned with the radio axis, suggesting a direct causal link between the outflowing gas and the radio jets. The complex velocity structure may be a result of different driving mechanisms related to the onset of the radio jets. We also present the results from the line-ratio diagnostics we used to analyze the ionization mechanism of the extended gas, which supports the scenario where the emission-line regions are ionized by a combination of active galactic nucleus radiation and shock excitation.

  10. Optically thick outflows in ultraluminous supersoft sources

    NASA Astrophysics Data System (ADS)

    Urquhart, R.; Soria, R.

    2016-02-01

    Ultraluminous supersoft sources (ULSs) are defined by a thermal spectrum with colour temperatures ˜0.1 keV, bolometric luminosities ˜ a few 1039 erg s-1, and almost no emission above 1 keV. It has never been clear how they fit into the general scheme of accreting compact objects. To address this problem, we studied a sample of seven ULSs with extensive Chandra and XMM-Newton coverage. We find an anticorrelation between fitted temperatures and radii of the thermal emitter, and no correlation between bolometric luminosity and radius or temperature. We compare the physical parameters of ULSs with those of classical supersoft sources, thought to be surface-nuclear-burning white dwarfs, and of ultraluminous X-ray sources (ULXs), thought to be super-Eddington stellar-mass black holes. We argue that ULSs are the sub-class of ULXs seen through the densest wind, perhaps an extension of the soft-ultraluminous regime. We suggest that in ULSs, the massive disc outflow becomes effectively optically thick and forms a large photosphere, shrouding the inner regions from our view. Our model predicts that when the photosphere expands to ≳ 105 km and the temperature decreases below ≈50 eV, ULSs become brighter in the far-UV but undetectable in X-rays. Conversely, we find that harder emission components begin to appear in ULSs when the fitted size of the thermal emitter is smallest (interpreted as a shrinking of the photosphere). The observed short-term variability and absorption edges are also consistent with clumpy outflows. We suggest that the transition between ULXs (with a harder tail) and ULSs (with only a soft thermal component) occurs at blackbody temperatures of ≈150 eV.

  11. A high-speed bipolar outflow from the archetypical pulsating star Mira A

    NASA Astrophysics Data System (ADS)

    Meaburn, J.; López, J. A.; Boumis, P.; Lloyd, M.; Redman, M. P.

    2009-06-01

    Optical images and high-dispersion spectra have been obtained of the ejected material surrounding the pulsating AGB star Mira A. The two streams of knots on either side of the star, found in far-ultraviolet (FUV) GALEX images, have now been imaged clearly in the light of Hα. Spatially resolved profiles of the same line reveal that the bulk of these knots form a bipolar outflow with radial velocity extremes of ±150 km s-1 with respect to the central star. The south stream is approaching and the north stream receding from the observer. A displacement away from Mira A between the position of one of the south-stream knots in the new Hα image and its position in the previous Palomar Observatory Sky Survey (POSS I) red plate was noted. If interpreted as a consequence of expansion proper motions, the bipolar outflow is tilted at 69° ± 15° to the plane of the sky, has an outflow velocity of 160 ± 10 km s-1 and is ≈1000 y old.

  12. High-resolution CO Observation of the Carbon Star CIT 6 Revealing the Spiral Structure and a Nascent Bipolar Outflow

    NASA Astrophysics Data System (ADS)

    Kim, Hyosun; Liu, Sheng-Yuan; Hirano, Naomi; Zhao-Geisler, Ronny; Trejo, Alfonso; Yen, Hsi-Wei; Taam, Ronald E.; Kemper, Francisca; Kim, Jongsoo; Byun, Do-Young; Liu, Tie

    2015-11-01

    CIT 6 is a carbon star in the transitional phase from the asymptotic giant branch (AGB) to the protoplanetary nebulae (pPNs). Observational evidences of two point sources in the optical, circumstellar arc segments in an HC3N line emission, and a bipolar nebula in near-infrared provide strong support for the presence of a binary companion. Hence, CIT 6 is very attractive for studying the role of companions in the AGB-pPN transition. We have carried out high-resolution 12CO J = 2-1 and 13CO J = 2-1 observations of CIT 6 with the Submillimeter Array combined with the Submillimeter Telescope (single-dish) data. The 12CO channel maps reveal a spiral-shell pattern connecting the HC3N segments in a continuous form and an asymmetric outflow corresponding to the near-infrared bipolar nebula. Rotation of the 12CO channel peak position may be related to the inner spiral winding and/or the bipolar outflow. An eccentric orbit binary is suggested for the presence of an anisotropic mass loss to the west and a double spiral pattern. The lack of interarm emission to the west may indicate a feature corresponding to the periastron passage of a highly eccentric orbit of the binary. Spatially averaged radial and spectral profiles of 12CO J = 2-1 and 13CO J = 2-1 are compared with simple spherical radiative transfer models, suggesting a change of 12CO/13CO abundance ratio from ˜30 to ˜50 inward in the CSE of CIT 6. The millimeter continuum emission is decomposed into extended dust thermal emission (spectral index ˜ -2.4) and compact emission from radio photosphere (spectral index ˜ -2.0).

  13. Bipolar gas outflow from the nova V458 Vul

    NASA Astrophysics Data System (ADS)

    Goranskij, V. P.; Barsukova, E. A.; Fatkhullin, T. A.

    2010-06-01

    Classical nova V458 Vul (N Vul 2007 No.1) was detected as a supersoft X-ray source by the Swift XRT (ATel#1246, #1603). This star is interesting with its spectral class change: features of Fe II class nova completely changed by features of He/N class in the SSS phase (T.N. Tarasova, IBVS No.5807). We performed spectral observations of V458 Vul with the Russian 6-m telescope BTA and spectral camera SCORPIO on 2010 June 9.84 UT.

  14. Multiple outflows in the bipolar planetary nebula M1-16: A molecular line study

    NASA Technical Reports Server (NTRS)

    Sahai, Raghvendra; Wootten, Alwyn; Schwarz, Hugo E.; Wild, W.

    1994-01-01

    Extensive observations of the molecular gas in the young, compact planetary nebula M1-16 have been made, using the Swedish-ESO-Submillimeter Telescope. A map of the CO J = 2-1 emission shows that the molecular envelope contains both a slow and a fast outflow with expansion velocities of 19 km/s and greater than 34 km/s, respectively. The slow outflow is mildly elliptical, while the fast molecular outflow is bipolar. This fast outflow is roughly aligned with the very fast outflows recently found in the optical, while the long axis of the slow elliptical outflow is roughly orthogonal to the optical outflow axis. The kinematic timescales for the CO fast outflow and the optical very fast outflow agree closely, supporting the view that the former represents material in the slow outflow accelerated by the very fast outflow. The kinematic signature of a disk expanding with about 15.5 km/s can also be seen in the CO J = 2-1 data. The mass-loss rate (a) for the slow outflow is greater than or equal to 2.8 x 10(exp -5) solar mass/yr and possibly as large as 9 x 10(exp -5) solar mass/yr, (b) for the fast outflow is greater than or equal to 5 x 10(exp -6) solar mass/yr, and (c) for the very fast optically visible outflow is approximately equal 5 x 10(exp -7) solar mass/yr. The disk mass is approximately equal 6 x 10(exp -3) solar mass. Grain photoelectric heating results in temperatures of 20-70 K in molecular gas of the slow outflow. The (13)C/(12)C abundance ratio in M1-16 is found to be 0.33, quite possibly the highest found for any evolved object. Upper limits for the (18)O/(16)O and (17)O/(16)O ratios were found to be consistent with the values found in AGB stars. A search for other molecular species in M1-16 resulted in the detection of the high-excitation species HCN, CN, (13)CN, HCO(+), and H(13)CO(+) and possibly N2H(+). Both the HCO(+)/HCN and CN/HCN line-intensity ratios are enhanced, the former by a very large factor, over the values found in the envelopes of AGB

  15. A BIPOLAR OUTFLOW FROM THE MASSIVE PROTOSTELLAR CORE W51e2-E

    SciTech Connect

    Shi Hui; Han, J. L.; Zhao Junhui E-mail: hil@nao.cas.c

    2010-08-01

    We present high-resolution images of the bipolar outflow from W51e2, which are produced from the Submillimeter Array archival data observed for CO(3-2) and HCN(4-3) lines with angular resolutions of 0.''8 x 0.''6 and 0.''3 x 0.''2, respectively. The images show that the powerful outflow originates from the protostellar core W51e2-E rather than from the ultracompact H II region W51e2-W. The kinematic timescale of the outflow from W51e2-E is about 1000 yr, younger than the age ({approx}5000 yr) of the ultracompact H II region W51e2-W. A large mass-loss rate of {approx}1 x 10{sup -3} M{sub sun} yr{sup -1} and a high mechanical power of 120 L{sub sun} are inferred, suggesting that an O star or a cluster of B stars are forming in W51e2-E. The observed outflow activity along with the inferred large accretion rate indicates that at present W51e2-E is in a rapid phase of star formation.

  16. Hu 1-2: a metal-poor bipolar planetary nebula with fast collimated outflows

    NASA Astrophysics Data System (ADS)

    Fang, X.; Guerrero, M. A.; Miranda, L. F.; Riera, A.; Velázquez, P. F.; Raga, A. C.

    2015-09-01

    We present narrow-band optical and near-IR imaging and optical long-slit spectroscopic observations of Hu 1-2, a Galactic planetary nebula (PN) with a pair of [N II]-bright, fast-moving (>340 km s-1) bipolar knots. Intermediate-dispersion spectra are used to derive physical conditions and abundances across the nebula, and high-dispersion spectra to study the spatio-kinematical structure. Generally, Hu 1-2 has high He/H (≈0.14) and N/O ratios (≈0.9), typical of Type I PNe. On the other hand, its abundances of O, Ne, S, and Ar are low as compared with the average abundances of Galactic bulge and disc PNe. The position-velocity maps can be generally described as an hour-glass shaped nebula with bipolar expansion, although the morphology and kinematics of the innermost regions cannot be satisfactorily explained with a simple, tilted equatorial torus. The spatio-kinematical study confines the inclination angle of its major axis to be within 10° of the plane of sky. As in the irradiated bow-shocks of IC 4634 and NGC 7009, there is a clear stratification in the emission peaks of [O III], Hα, and [N II] in the north-west (NW) knot of Hu 1-2. Fast collimated outflows in PNe exhibit higher excitation than other low-ionization structures. This is particularly the case for the bipolar knots of Hu 1-2, with He II emission levels above those of collimated outflows in other Galactic PNe. The excitation of the knots in Hu 1-2 is consistent with the combined effects of shocks and UV radiation from the central star. The mechanical energy and luminosity of the knots are similar to those observed in the PNe known to harbour a post-common envelope (post-CE) close binary central star.

  17. Spiral-shells and nascent bipolar outflow in CIT 6: hints for an eccentric-orbit binary?

    NASA Astrophysics Data System (ADS)

    Kim, Hyosun; Liu, Sheng-Yuan; Hirano, Naomi; Zhao-Geisler, Ronny; Trejo, Alfonso; Yen, Hsi-Wei; Taam, Ronald E.; Kemper, Francisca; Kim, Jongsoo; Byun, Do-Young; Liu, Tie

    2016-07-01

    We present the essential results pointed out in a recently published paper, Kim et al. 2015, Astrophys. J., 814, 61. The carbon star CIT 6 reveals evidences for a binary in a high-resolution CO line emission map of its circumstellar envelope taken with the Submillimeter Array. The morphology of the outflow described by the spiral-shell pattern, bipolar (or possibly multipolar) outflow, one-sided interarm gaps, and double spiral feature point to a plausible scenario that CIT 6 is a binary system in an eccentric orbit with the mass losing star evolving from the AGB.

  18. Submillimeter array observations of NGC 2264-C: molecular outflows and driving sources

    NASA Astrophysics Data System (ADS)

    Cunningham, Nichol; Lumsden, Stuart L.; Cyganowski, Claudia J.; Maud, Luke T.; Purcell, Cormac

    2016-05-01

    We present 1.3 mm Submillimeter Array (SMA) observations at ˜3 arcsec resolution towards the brightest section of the intermediate/massive star-forming cluster NGC 2264-C. The millimetre continuum emission reveals ten 1.3 mm continuum peaks, of which four are new detections. The observed frequency range includes the known molecular jet/outflow tracer SiO (5-4), thus providing the first high-resolution observations of SiO towards NGC 2264-C. We also detect molecular lines of 12 additional species towards this region, including CH3CN, CH3OH, SO, H2CO, DCN, HC3N, and 12CO. The SiO (5-4) emission reveals the presence of two collimated, high-velocity (up to 30 km s-1 with respect to the systemic velocity) bipolar outflows in NGC 2264-C. In addition, the outflows are traced by emission from 12CO, SO, H2CO, and CH3OH. We find an evolutionary spread between cores residing in the same parent cloud. The two unambiguous outflows are driven by the brightest mm continuum cores, which are IR-dark, molecular line weak, and likely the youngest cores in the region. Furthermore, towards the Red MSX Source AFGL 989-IRS1, the IR-bright and most evolved source in NGC 2264-C, we observe no molecular outflow emission. A molecular line rich ridge feature, with no obvious directly associated continuum source, lies on the edge of a low-density cavity and may be formed from a wind driven by AFGL 989-IRS1. In addition, 229 GHz class I maser emission is detected towards this feature.

  19. Identification of the Exciting Source of CO Outflow in the Star-Formation Region GGD 12-15

    NASA Astrophysics Data System (ADS)

    Sato, Yaeko; Tamura, Motohide; Kandori, Ryo; Nakajima, Yasushi; Kusakabe, Nobuhiko; Hashimoto, Jun; Kudo, Tomoyuki; Saito, Hiroo; Kitamura, Yoshimi; Kawamura, Akiko; Nishiyama, Shogo; Sunada, Kazuyoshi; Ueno, Munetaka

    2008-12-01

    We present results of near-infrared imaging polarimetry of the GGD 12-15 region with the IRSF 1.4m telescope and the SIRIUS camera/SIRPOL polarimeter and mid-infrared imaging with the AKARI telescope and the Infra-Red Camera (IRC). Two infrared sources, IRS9E and IRS9M near an H2O maser source situated on both sides around a VLA source (VLA7), have been believed to be two bipolar lobes associated with a massive CO outflow. However, our polarimetric observations have revealed that IRS9E is stellar-like, and not part of a reflection nebula. Furthermore, IRS9M itself is not stellar, but a bipolar nebula, extending north-south. Both polarization vector maps and polarized intensity images show that the true illuminating source, IRS9Mc, is not resolved, and is situated near the peak of the intensity image. Our astrometry also indicates that the position of IRS9Mc does not coincide with the water maser position, but rather coincides with the VLA7 position. We suggest that the unresolved illuminating source IRS9Mc is the true exciting source of the CO outflow, corresponding to amid-infrared source detected by AKARI with a lower spatial resolution. Fluxes of the newly identified source at 1 to 11μm were derived by separating contributions from nearby infrared sources; the spectral energy distribution is consistent with that of a class I/0 source.

  20. Resolved Spectroscopy of a Gravitationally Lensed L^{*} Lyman Break Galaxy at z˜5: Evidence for a Starburst-Driven, Galactic-Scale Bi-Polar Outflow

    NASA Astrophysics Data System (ADS)

    Swinbank, M.

    2007-12-01

    We exploit the gravitational potential of a massive, rich cluster as a natural magnifying glass to study the internal properties of the highly magnified galaxy at z=4.88. Using high resolution HST imaging we construct a detailed mass model and, together with optical (VIMOS) and near-infrared (SINFONI) Integral Field Spectroscopy, we have mapped the source-frame morphology of the lensed galaxy behind galaxy cluster RCS0224-002 on 200pc scales to find an ˜L^{*} Lyman-break galaxy with a dynamical mass of 1.0×10^{10} M_{⊙} within 2 kpc and infer an integrated star-formation rate of just 12±2 M_{⊙} yr^{-1}. By combing the spatially resolved velocities from the [O II] and Lyα emission and UV ISM absorption lines we suggest that this galaxy is surrounded by a galactic-scale bi-polar outflow which has recently burst out of the system and is escaping at a speed of ˜500 km s^{-1}. The geometry and velocity of the outflow suggests that the ejected material is travelling far faster than escape velocity and we estimate that it will travel at least 1 Mpc (comoving) before eventually stalling. The enriched, outflowing material is therefore efficient at expelling baryons which are likely to subsequently play no further part in the star-formation history of this galaxy, but rather will pollute the IGM in a volume of at least 3Mpc^{3}.

  1. AN INFRARED-LUMINOUS MERGER WITH TWO BIPOLAR MOLECULAR OUTFLOWS: ALMA AND SMA OBSERVATIONS OF NGC 3256

    SciTech Connect

    Sakamoto, Kazushi; Aalto, Susanne; Combes, Francoise; Evans, Aaron; Peck, Alison

    2014-12-20

    We report Atacama Large Millimeter/sub-millimeter Array and Submillimeter Array observations of the infrared-luminous merger NGC 3256, the most luminous galaxy within z = 0.01. Both of the two merger nuclei separated by 5'' (0.8 kpc) have a molecular gas concentration, a nuclear disk, with Σ{sub mol} > 10{sup 3} M {sub ☉} pc{sup –2}. The northern nucleus is more massive and is surrounded by molecular spiral arms. Its nuclear disk is face-on, while the southern nuclear disk is almost edge-on. The high-velocity molecular gas in the system can be resolved into two molecular outflows from the two nuclei. The one from the northern nucleus is part of a starburst-driven superwind seen nearly pole-on. Its maximum velocity is >750 km s{sup –1} and its mass outflow rate is >60 M {sub ☉} yr{sup –1} for a conversion factor X{sub CO}=N{sub H{sub 2}}/I{sub CO(1−0)} of 1 × 10{sup 20} cm{sup –2} (K km s{sup –1}){sup –1}. The molecular outflow from the southern nucleus is a highly collimated bipolar jet seen nearly edge-on. Its line-of-sight velocity increases with distance, out to 300 pc from the nucleus, to the maximum de-projected velocity of ∼2000 km s{sup –1} for the estimated inclination and ≳1000 km s{sup –1} taking into account the uncertainty. Its mass outflow rate is estimated to be >50 M {sub ☉} yr{sup –1} for the same X {sub CO}. This southern outflow has indications of being driven by a bipolar radio jet from an active galactic nucleus that recently weakened. The sum of these outflow rates, although subject to the uncertainty in the molecular mass estimate, either exceeds or compares to the total star formation rate. The feedback from nuclear activity through molecular outflows is therefore significant in the gas consumption, and hence evolution, of this system.

  2. On the possible bipolar nature of 21 micron IRAS sources

    NASA Technical Reports Server (NTRS)

    Hrivnak, Bruce J.; Kwok, S.

    1991-01-01

    The discovery of another IRAS source (22574 + 6609) showing the unidentified 21-micron emission feature is reported. Its overall energy distribution is similar to the well-known edge-on bipolar nebulae AFGL 2688 and AFGL 618. Ground-based optical and infrared observations of this object and two other 21-micron sources show that while all three have very similar infrared properties, they differ greatly in the visual region. All three of these 21-micron sources are intrinsically similar bipolar nebulae, viewed at different orientations.

  3. Evaluation of nitrous acid sources and sinks in urban outflow

    NASA Astrophysics Data System (ADS)

    Gall, Elliott T.; Griffin, Robert J.; Steiner, Allison L.; Dibb, Jack; Scheuer, Eric; Gong, Longwen; Rutter, Andrew P.; Cevik, Basak K.; Kim, Saewung; Lefer, Barry; Flynn, James

    2016-02-01

    Intensive air quality measurements made from June 22-25, 2011 in the outflow of the Dallas-Fort Worth (DFW) metropolitan area are used to evaluate nitrous acid (HONO) sources and sinks. A two-layer box model was developed to assess the ability of established and recently identified HONO sources and sinks to reproduce observations of HONO mixing ratios. A baseline model scenario includes sources and sinks established in the literature and is compared to scenarios including three recently identified sources: volatile organic compound-mediated conversion of nitric acid to HONO (S1), biotic emission from the ground (S2), and re-emission from a surface nitrite reservoir (S3). For all mechanisms, ranges of parametric values span lower- and upper-limit values. Model outcomes for 'likely' estimates of sources and sinks generally show under-prediction of HONO observations, implying the need to evaluate additional sources and variability in estimates of parameterizations, particularly during daylight hours. Monte Carlo simulation is applied to model scenarios constructed with sources S1-S3 added independently and in combination, generally showing improved model outcomes. Adding sources S2 and S3 (scenario S2/S3) appears to best replicate observed HONO, as determined by the model coefficient of determination and residual sum of squared errors (r2 = 0.55 ± 0.03, SSE = 4.6 × 106 ± 7.6 × 105 ppt2). In scenario S2/S3, source S2 is shown to account for 25% and 6.7% of the nighttime and daytime budget, respectively, while source S3 accounts for 19% and 11% of the nighttime and daytime budget, respectively. However, despite improved model fit, there remains significant underestimation of daytime HONO; on average, a 0.15 ppt/s unknown daytime HONO source, or 67% of the total daytime source, is needed to bring scenario S2/S3 into agreement with observation. Estimates of 'best fit' parameterizations across lower to upper-limit values results in a moderate reduction of the unknown

  4. On the Thermal Line Emission from the Outflows in Ultraluminous X-Ray Sources

    NASA Astrophysics Data System (ADS)

    Xu, Ya-Di; Cao, Xinwu

    2016-08-01

    The atomic features in the X-ray spectra of ultraluminous X-ray sources (ULXs) may be associated with the outflow, which may provide a way to explore the physics of the ULXs. We construct a conical outflow model and calculate the thermal X-ray Fe emission lines from the outflows. Our results show that thermal line luminosity decreases with increasing outflow velocity and/or opening angle of the outflow for a fixed kinetic power of the outflows. Assuming the kinetic power of the outflows to be comparable with the accretion power in the ULXs, we find that the equivalent width can be several eV for the thermal X-ray Fe emission line from the outflows in the ULXs with stellar-mass black holes. The thermal line luminosity is proportional to 1/M bh (M bh is the black hole mass of the ULX). The equivalent width decreases with the black hole mass, which implies that the Fe line emission from the outflows can hardly be detected if the ULXs contain intermediate-mass black holes. Our results suggest that the thermal X-ray Fe line emission should be preferentially be detected in the ULXs with high kinetic power slowly moving outflows from the accretion disks surrounding stellar-mass black holes/neutron stars. The recently observed X-ray atomic features of the outflows in a ULX may imply that it contains a stellar-mass black hole.

  5. Bipolar outflows as a repulsive gravitational phenomenon — Azimuthally Symmetric Theory of Gravitation (II)

    NASA Astrophysics Data System (ADS)

    Nyambuya, Golden Gadzirayi

    2010-11-01

    This paper is part of a series on the Azimuthally Symmetric Theory of Gravitation (ASTG). This theory is built on Laplace-Poisson's well known equation and it has been shown that the ASTG is capable of explaining, from a purely classical physics standpoint, the precession of the perihelion of solar planets as a consequence of the azimuthal symmetry emerging from the spin of the Sun. This symmetry has and must have an influence on the emergent gravitational field. We show herein that the emergent equations from the ASTG, under some critical conditions determined by the spin, do possess repulsive gravitational fields in the polar regions of the gravitating body in question. This places the ASTG on an interesting pedestal to infer the origins of outflows as a repulsive gravitational phenomenon. Outflows are a ubiquitous phenomenon found in star forming systems and their true origin is a question yet to be settled. Given the current thinking on their origin, the direction that the present paper takes is nothing short of an asymptotic break from conventional wisdom; at the very least, it is a complete paradigm shift because gravitation is not at all associated with this process, but rather it is thought to be an all-attractive force that only tries to squash matter together onto a single point. Additionally, we show that the emergent Azimuthally Symmetric Gravitational Field from the ASTG strongly suggests a solution to the supposed Radiation Problem that is thought to be faced by massive stars in their process of formation. That is, at ~ 8-10 , radiation from the nascent star is expected to halt the accretion of matter. We show that in-falling material will fall onto the equatorial disk and from there, this material will be channeled onto the forming star via the equatorial plane, thus accretion of mass continues well past the value of ~ 8-10 , albeit via the disk. Along the equatorial plane, the net force (with the radiation force included) on any material there

  6. Caught in the Act: Imaging the Disk and Outflows in V Hya, a carbon-rich AGB star in transition to a Bipolar Pre-Planetary Nebula

    NASA Astrophysics Data System (ADS)

    Sahai, Raghvendra; Rajagopal, Jayadev; Morris, Mark; Hinkle, Kenneth H.; Joyce, Richard R.

    2015-01-01

    The carbon star V Hya is experiencing heavy mass loss as it undergoes the transition from AGB star to a bipolar pre-planetary nebula (PPN). V Hya is possibly the earliest object known in this brief phase, which is so short that few nearby stars are likely to be caught in the act. Using STIS/HST we discovered a high velocity (>200 km/s) blob that was ejected very recently from near (<0.3 arcsec) the star and measured its proper motion. We found time-variable high-velocity absorption features in the CO 4.6 micron vibration-rotation lines from a multi-epoch study - modelling shows that these are produced in compact clumps of outflowing gas with significant temperature gradients. Millimeter wave interferometry with 3.5 arcsec resolution shows that the high-velocity outflow is collimated and bipolar. The STIS data and recent mid-infrared interferometry also suggest the presence of a small (<0.55 arcsec size) circumstellar disk.We report new observations to investigate V Hya's high-velocity outflow and disk with STIS (HST) and GPI (Gemini South). Our STIS data show that the high-velocity outflow emission has weakened significantly over a 12-year period. Our Y-band coronagraphic polarimetric imaging with GPI reveals the presence of an inclined disk in scattered light, aligned roughly north-south, i.e., orthogonal to the high-velocity outflow. We discuss the implications of these results for the disk/outflow system in V Hya in particular, and in nascent PPNe, in general.

  7. Solar Jets as Sources of Outflows, Heating and Waves

    NASA Astrophysics Data System (ADS)

    Nishizuka, N.

    2013-05-01

    Recent space solar observations of the Sun, such as Hinode and SDO, have revealed that magnetic reconnection is ubiquitous in the solar atmosphere, ranging from small scale reconnection (observed as nanoflares) to large scale one (observed as long duration flares or giant arcades). Especially recent Hinode observations has found various types of tiny chromospheric jets, such as chromospheric anemone jets, penumbral microjets and light bridge jets from sunspot umbra. It was also found that the corona is full of tiny X-ray jets. Often they are seen as helical spinning jets with Alfvenic waves in the corona. Sometimes they are seen as chromospheric jets with slow-mode magnetoacoustic waves and sometimes as unresolved jet-like events at the footpoint of recurrent outflows and waves at the edge of the active region. There is increasing evidence of magnetic reconnection in these tiny jets and its association with waves. The origin of outflows and waves is one of the issues concerning coronal heating and solar wind acceleration. To answer this question, we had a challenge to reproduce solar jets with laboratory plasma experiment and directly measured outflows and waves. As a result, we could find a propagating wave excited by magnetic reconnection, whose energy flux is 10% of the released magnetic energy. That is enough for solar wind acceleration and locally enough for coronal heating, consistent with numerical MHD simulations of solar jets. Here we would discuss recent observations with Hinode, theories and experimental results related to jets and waves by magnetic reconnection, and discuss possible implication to reconnection physics, coronal heating and solar wind acceleration.

  8. Martian outflow channels: How did their source aquifers form, and why did they drain so rapidly?

    PubMed

    Rodriguez, J Alexis P; Kargel, Jeffrey S; Baker, Victor R; Gulick, Virginia C; Berman, Daniel C; Fairén, Alberto G; Linares, Rogelio; Zarroca, Mario; Yan, Jianguo; Miyamoto, Hideaki; Glines, Natalie

    2015-01-01

    Catastrophic floods generated ~3.2 Ga by rapid groundwater evacuation scoured the Solar System's most voluminous channels, the southern circum-Chryse outflow channels. Based on Viking Orbiter data analysis, it was hypothesized that these outflows emanated from a global Hesperian cryosphere-confined aquifer that was infused by south polar meltwater infiltration into the planet's upper crust. In this model, the outflow channels formed along zones of superlithostatic pressure generated by pronounced elevation differences around the Highland-Lowland Dichotomy Boundary. However, the restricted geographic location of the channels indicates that these conditions were not uniform. Furthermore, some outflow channel sources are too high to have been fed by south polar basal melting. Using more recent mission data, we argue that during the Late Noachian fluvial and glacial sediments were deposited into a clastic wedge within a paleo-basin located in the southern circum-Chryse region, which at the time was completely submerged under a primordial northern plains ocean [corrected]. Subsequent Late Hesperian outflow channels were sourced from within these geologic materials and formed by gigantic groundwater outbursts driven by an elevated hydraulic head from the Valles Marineris region. Thus, our findings link the formation of the southern circum-Chryse outflow channels to ancient marine, glacial, and fluvial erosion and sedimentation. PMID:26346067

  9. Martian outflow channels: How did their source aquifers form, and why did they drain so rapidly?

    PubMed Central

    Rodriguez, J. Alexis P.; Kargel, Jeffrey S.; Baker, Victor R.; Gulick, Virginia C.; Berman, Daniel C.; Fairén, Alberto G.; Linares, Rogelio; Zarroca, Mario; Yan, Jianguo; Miyamoto, Hideaki; Glines, Natalie

    2015-01-01

    Catastrophic floods generated ~3.2 Ga by rapid groundwater evacuation scoured the Solar System’s most voluminous channels, the southern circum-Chryse outflow channels. Based on Viking Orbiter data analysis, it was hypothesized that these outflows emanated from a global Hesperian cryosphere-confined aquifer that was infused by south polar meltwater infiltration into the planet’s upper crust. In this model, the outflow channels formed along zones of superlithostatic pressure generated by pronounced elevation differences around the Highland-Lowland Dichotomy Boundary. However, the restricted geographic location of the channels indicates that these conditions were not uniform Boundary. Furthermore, some outflow channel sources are too high to have been fed by south polar basal melting. Using more recent mission data, we argue that during the Late Noachian fluvial and glacial sediments were deposited into a clastic wedge within a paleo-basin located in the southern circum-Chryse region, which was then completely submerged under a primordial northern plains ocean. Subsequent Late Hesperian outflow channels were sourced from within these geologic materials and formed by gigantic groundwater outbursts driven by an elevated hydraulic head from the Valles Marineris region. Thus, our findings link the formation of the southern circum-Chryse outflow channels to ancient marine, glacial, and fluvial erosion and sedimentation. PMID:26346067

  10. Martian outflow channels: How did their source aquifers form, and why did they drain so rapidly?

    NASA Astrophysics Data System (ADS)

    Rodriguez, J. Alexis P.; Kargel, Jeffrey S.; Baker, Victor R.; Gulick, Virginia C.; Berman, Daniel C.; Fairén, Alberto G.; Linares, Rogelio; Zarroca, Mario; Yan, Jianguo; Miyamoto, Hideaki; Glines, Natalie

    2015-09-01

    Catastrophic floods generated ~3.2 Ga by rapid groundwater evacuation scoured the Solar System’s most voluminous channels, the southern circum-Chryse outflow channels. Based on Viking Orbiter data analysis, it was hypothesized that these outflows emanated from a global Hesperian cryosphere-confined aquifer that was infused by south polar meltwater infiltration into the planet’s upper crust. In this model, the outflow channels formed along zones of superlithostatic pressure generated by pronounced elevation differences around the Highland-Lowland Dichotomy Boundary. However, the restricted geographic location of the channels indicates that these conditions were not uniform Boundary. Furthermore, some outflow channel sources are too high to have been fed by south polar basal melting. Using more recent mission data, we argue that during the Late Noachian fluvial and glacial sediments were deposited into a clastic wedge within a paleo-basin located in the southern circum-Chryse region, which was then completely submerged under a primordial northern plains ocean. Subsequent Late Hesperian outflow channels were sourced from within these geologic materials and formed by gigantic groundwater outbursts driven by an elevated hydraulic head from the Valles Marineris region. Thus, our findings link the formation of the southern circum-Chryse outflow channels to ancient marine, glacial, and fluvial erosion and sedimentation.

  11. Outflow in global magnetohydrodynamics as a function of a passive inner boundary source

    NASA Astrophysics Data System (ADS)

    Welling, D. T.; Liemohn, M. W.

    2014-04-01

    Numerous studies of the terrestrial magnetosphere that use global magnetohydrodynamic codes have found that the model's inner boundary can act as a significant source of plasma, even if the radial velocity about the boundary is held at zero. Though inherent in many models, this "de facto outflow" is poorly understood. This work uses the Block Adaptive Tree Solar Wind Roe-type Upwind Scheme MHD model to investigate the behavior of this type of outflow as a function of boundary conditions and solar wind drivers. It is found that even for temporally and spatially constant boundary conditions, the mass is accelerated away from the body in a dynamic manner. Fluxes organize into cusp, polar cap, and auroral zone concentrations. Pressure gradient forces appear predominantly responsible for cusp and polar cap outflow, while the Lorentz force, resulting from field-aligned current systems, is the strongest driver of outflow in other regions. Integrated fluxes probed just outside of the inner boundary vary linearly as a function of cross polar cap potential and solar wind dynamic pressure. The resulting dynamics strongly resemble patterns found in in situ measurements, while net fluences agree within an order of magnitude. Two free parameters, inner boundary mass density and composition, can strongly affect results. Accounting for these unknowns is likely best left to physics-based or empirical specifications of outflow. Despite this, such outflow appears to be an acceptable proxy.

  12. Jet rotation: Launching region, angular momentum balance and magnetic properties in the bipolar outflow from RW Aur

    NASA Astrophysics Data System (ADS)

    Woitas, J.; Bacciotti, F.; Ray, T. P.; Marconi, A.; Coffey, D.; Eislöffel, J.

    2005-03-01

    Using STIS on board the HST we have obtained a spectroscopic map of the bipolar jet from RW Aur with the slit parallel to the jet axis and moved across the jet in steps of 0.07 arcsec. After applying a velocity correction due to uneven slit illumination we find signatures of rotation within the first 300 AU of the jet (1.5 arcsec at the distance of RW Aur). Both lobes rotate in the same direction (i.e. with different helicities), with toroidal velocities in the range 5-30 km s-1 at 20 and 30 AU from the symmetry axis in the blueshifted and redshifted lobes, respectively. The sense of rotation is anti-clockwise looking from the tip of the blue lobe (PA 130° north to east) down to the star. Rotation is more evident in the [OI] and [NII] lines and at the largest sampled distance from the axis. These results are consistent with other STIS observations carried out with the slit perpendicular to the jet axis, and with theoretical simulations. Using current magneto-hydrodynamic models for the launch of the jets, we find that the mass ejected in the observed part of the outflow is accelerated from a region in the disk within about 0.5 AU from the star for the blue lobe, and within 1.6 AU from the star for the red lobe. Using also previous results we estimate upper and lower limits for the angular momentum transport rate of the jet. We find that this can be a large fraction (two thirds or more) of the estimated rate transported through the relevant portion of the disk. The magnetic lever arm (defined as the ratio rA/r0 between the Alfvèn and footpoint radii) is in the range 3.5-4.6 (with an accuracy of 20-25%), or, alternatively, the ejection index ξ = dln (dot{M}acc ) / d r is in the range 0.025-0.046 (with similar uncertainties). The derived values are in the range predicted by the models, but they also suggest that some heating must be provided at the base of the flow. Finally, using the general disk wind theory we derive the ratio Bφ / Bp of the toroidal and

  13. The radio source and bipolar nebulosity in the Seyfert galaxy NGC 3516

    NASA Technical Reports Server (NTRS)

    Miyaji, Takamitsu; Wilson, Andrew S.; Perez-Fournon, Ismael

    1992-01-01

    Results of radio continuum and optical emission-line observations of the type 1 Seyfert galaxy NGC 3516 are presented. The radio maps reveal an elongated one-sided curved structure, which comprises a series of small-scale 'blobs' and extends up to 4 kpc from the nucleus. This radio structure is aligned and cospatial with one side of the double-sided and highly symmetric Z-shaped emission-line structure. It is argued that these morphological features are associated with a bipolar gaseous outflow from the nucleus of NGC 3516. The radio 'blobs' are elongated roughly perpendicular to the apparent local direction of the outflow, a result which is interpreted in terms of synchrotron emission from outflow-driven shock waves.

  14. Geochemistry and source waters of rock glacier outflow, Colorado Front Range

    USGS Publications Warehouse

    Williams, M.W.; Knauf, M.; Caine, N.; Liu, F.; Verplanck, P.L.

    2006-01-01

    We characterize the seasonal variation in the geochemical and isotopic content of the outflow of the Green Lake 5 rock glacier (RG5), located in the Green Lakes Valley of the Colorado Front Range, USA. Between June and August, the geochemical content of rock glacier outflow does not appear to differ substantially from that of other surface waters in the Green Lakes Valley. Thus, for this alpine ecosystem at this time of year there does not appear to be large differences in water quality among rock glacier outflow, glacier and blockslope discharge, and discharge from small alpine catchments. However, in September concentrations of Mg2+ in the outflow of the rock glacier increased to more than 900 ??eq L-1 compared to values of less than 40 ??eq L-1 at all the other sites, concentrations of Ca2+ were greater than 4,000 ??eq L-1 compared to maximum values of less than 200 ??eq L-1 at all other sites, and concentrations of SO42- reached 7,000 ??eq L-1, compared to maximum concentrations below 120 ??eq L-1 at the other sites. Inverse geochemical modelling suggests that dissolution of pyrite, epidote, chlorite and minor calcite as well as the precipitation of silica and goethite best explain these elevated concentrations of solutes in the outflow of the rock glacier. Three component hydrograph separation using end-member mixing analysis shows that melted snow comprised an average of 30% of RG5 outflow, soil water 32%, and base flow 38%. Snow was the dominant source water in June, soil water was the dominant water source in July, and base flow was the dominant source in September. Enrichment of ?? 18O from - 10??? in the outflow of the rock glacier compared to -20??? in snow and enrichment of deuterium excess from +17.5??? in rock glacier outflow compared to +11??? in snow, suggests that melt of internal ice that had undergone multiple melt/freeze episodes was the dominant source of base flow. Copyright ?? 2005 John Wiley & Sons, Ltd.

  15. A bipolar outflow of ionized gas in K3-50A: H76 alpha radio recombination line and continuum observations of K3-50

    NASA Technical Reports Server (NTRS)

    Depree, C. G.; Goss, W. M.; Palmer, Patrick; Rubin, Robert H.

    1994-01-01

    The H II regions near K3-50 (G70.3 + 1.6) have been imaged at high angular resolution (approximately 1 sec .3) in the continuum and the recombination lines H76(sub alpha and He76(sub alpha) using the Very Large Array (VLA). The helium line is detected in only the brightest component K3-50A while the hydrogen line is detected in three components (K3-50A, B and C1). K3-50A shows a pronounced velocity gradient of approximately 150 km/sec/pc along its major axis (P.A. = 160 deg); in addition a wide range of line widths are observed, from 20 to 65 km/sec. Kinematics from the line data and the morphology of the continuum emission suggest that the ionized material associated with K3-50A is undergoing a high-velocity bipolar outflow.

  16. Source apportionment of light absorbing WSOC in South Asian outflow

    NASA Astrophysics Data System (ADS)

    Bosch, Carme; Kirillova, Elena; Andersson, August; Kruså, Martin; Budhavant, Krishnakant; Tiwari, Suresh; Gustafsson, Örjan

    2013-04-01

    Carbonaceous aerosols (CA) formed over South Asia are of special concern for human health and regional climate impacts. Anthropogenic emissions forming CA are generally high throughout the region and particularly over the Indo-Gangetic Plain. The net effects of CA on radiative climate forcing are still uncertain. One of the components of CA is black carbon (BC), dominated by soot-like elemental carbon, a strong absorber of solar radiation. Another component is organic carbon (OC), traditionally considered as a light scattering particle. However, recent field studies have shown OC to absorb at lower wavelengths. Thus OC, in addition to BC, may also contribute to light absorption and have a positive direct radiative effect on climate. Light absorbing organic aerosol is usually termed brown carbon (BrC). A significant fraction of BrC is water-soluble, therefore its dissolution into clouds could result in absorbing droplets that affect the cloud absorption and thus contributing to the indirect aerosol climate effects. In this study, light absorption and δ13C + Δ14C isotopic measurements of WSOC were studied in fine aerosols (PM 2.5) at two sites during early pre-monsoon season. New Delhi, one of the most densely populated and industrialized urban megacities in South Asia, was chosen to represent a strong source and Maldives Climate Observatory at Hanimaadhoo (MCOH) was chosen as a regional receptor which in wintertime is located downwind of the Indian subcontinent. Sampling in Delhi was done from mid-February to mid-March 2011 and in MCOH during March 2012. WSOC concentrations were 12±4.5 and 0.71±0.30 μg m-3 in Delhi and MCOH respectively. Whereas in Delhi WSOC contributed 31±4% of total organic carbon, this contribution was slightly higher in MCOH (40±12%). Light absorption by WSOC exhibited strong wavelength (?) dependence. In Maldives, WSOC Absorption Ångström Exponent (AAE) was found to be 6.9±0.4 and Mass Absorption Efficiency (MAE) measured at 365 nm

  17. Raman-scattered O VI λ1032 and He II λ1025 and Bipolar Outflow in the Symbiotic Star V455 Sco

    NASA Astrophysics Data System (ADS)

    Heo, Jeong-Eun; Angeloni, Rodolfo; Di Mille, Francesco; Palma, Tali; Chang, Seok-Jun; Hong, Chae-Lin; Lee, Hee-Won

    2016-07-01

    Raman-scattering by atomic hydrogen is a unique spectroscopic process that may probe the mass transfer and mass loss phenomena in symbiotic stars(SSs). In the optical high- resolution spectra of the S-type SS V455 Sco, we note the presence of two Raman-scattered features, one at around 6825 Å with a triple-peak profile formed from Raman-scattering of O VI λ1032 and the other Raman-scattered He II λ1025 at around 6545 Å. Adopting an accretion flow model with additional contribution from a collimated bipolar outflow, we propose that the blue and central peaks are contributed from the accretion flow and the bipolar flow is responsible for the remaining red peak. With the absence of [N II] λ6548, the Raman-scattered He II λ1025 at around 6545 Å is immersed in the broad Ha wings that appear to be formed by Raman-scattering of far-UV continuum near Lyman series.

  18. Infrared and optical imaging of IRAS sources with CO outflow - A snapshot of early star formation

    NASA Technical Reports Server (NTRS)

    Chen, H.; Tokunaga, A. T.; Strom, K. M.; Hodapp, K.-W.

    1993-01-01

    We present multiband imaging of three IRAS sources associated with CO molecular outflows. We find stellar density enhancements around all three IRAS sources. Optical and near-IR photometry indicates that at least 60 percent of the near-IR sources in the vicinity of the IRAS sources are pre-main-sequence stars. Using the photometric data at nbL and M, we are able to identify candidates for the near-IR counterparts of the IRAS sources. We also find that (1) the spectral energy distribution of the deeply embedded sources could be complicated by source confusion and scattered light from the young stellar objects; (2) star formation in the vicinity of the IRAS sources is a continuous process with an age span of 0.5-3 Myr; and (3) stellar density enhancement is probably a phenomenon found at the earliest stage of star formation.

  19. ALMA OBSERVATIONS OF THE MASSIVE MOLECULAR OUTFLOW G331.512-0.103

    SciTech Connect

    Merello, Manuel; Bronfman, Leonardo; Garay, Guido; Lo, Nadia; Evans, Neal J. II; Nyman, Lars-Ake; Cortes, Juan R.; Cunningham, Maria R.

    2013-09-01

    The object of this study is one of the most energetic and luminous molecular outflows known in the Galaxy, G331.512-0.103. Observations with ALMA Band 7 (350 GHz; 0.86 mm) reveal a very compact, extremely young bipolar outflow and a more symmetric outflowing shocked shell surrounding a very small region of ionized gas. The velocities of the bipolar outflow are about 70 km s{sup -1} on either side of the systemic velocity. The expansion velocity of the shocked shell is {approx}24 km s{sup -1}, implying a crossing time of about 2000 yr. Along the symmetry axis of the outflow, there is a velocity feature, which could be a molecular ''bullet'' of high-velocity dense material. The source is one of the youngest examples of massive molecular outflow found associated with a high-mass star.

  20. A spectacular molecular outflow in the Monoceros OB1 molecular cloud

    NASA Technical Reports Server (NTRS)

    Margulis, Michael; Lada, Charles J.; Hasegawa, Tetsuo; Hayashi, Saeko S.; Hayashi, Masihiko

    1990-01-01

    Detailed observations of CO, CS, IR continuum, and H2 emission from a large, highly collimated, bipolar outflow in the Monoceros OB1 molecular cloud are presented. The CO observations suggest that molecular gas in the outflow is contained in a shell with higher velocity material situated interior to lower velocity material. The velocities of outflow emission are found to increase with increasing distance from the center of the outflow. Additional detections include shock-excited molecular hydrogen emission from the blueshifted lobe of the outflow and six 2-micron sources in the direction of the outflow. Near-IR and IRAS observations suggest that the driving source for the outflow must have a bolometric luminosity below about 4.5 solar luminosities. It is concluded that the flow is probably not driven by stellar radiation from a central source.

  1. Seasonal variability of organic matter composition in an Alaskan glacier outflow: insights into glacier carbon sources

    NASA Astrophysics Data System (ADS)

    Spencer, Robert G. M.; Vermilyea, Andrew; Fellman, Jason; Raymond, Peter; Stubbins, Aron; Scott, Durelle; Hood, Eran

    2014-05-01

    Glacier ecosystems are a significant source of bioavailable, yet ancient dissolved organic carbon (DOC). Characterizing DOC in Mendenhall Glacier outflow (southeast Alaska) we document a seasonal persistence to the radiocarbon-depleted signature of DOC, highlighting ancient DOC as a ubiquitous feature of glacier outflow. We observed no systematic depletion in Δ 14C-DOC with increasing discharge during the melt season that would suggest mobilization of an aged subglacial carbon store. However, DOC concentration, δ 13C-DOC, Δ 14C-DOC and fluorescence signatures appear to have been influenced by runoff from vegetated hillslopes above the glacier during onset and senescence of melt. In the peak glacier melt period, the Δ 14C-DOC of stream samples at the outflow (-181.7 to -355.3‰) was comparable to the Δ 14C-DOC for snow samples from the accumulation zone (-207.2 to -390.9‰), suggesting that ancient DOC from the glacier surface is exported in glacier runoff. The pre-aged DOC in glacier snow and runoff is consistent with contributions from fossil fuel combustion sources similar to those documented previously in ice cores and thus provides evidence for anthropogenic perturbation of the carbon cycle. Overall, our results emphasize the need to further characterize DOC inputs to glacier ecosystems, particularly in light of predicted changes in glacier mass and runoff in the coming century.

  2. Reverse electrodialysis using bipolar ion-exchange membranes as a source of electric energy

    SciTech Connect

    Pivovarov, N.Ya.; Greben`, V.P.; Kovarskii, N.Ya.

    1994-06-01

    It is established that, in the regime of the H{sup +} and OH{sup {minus}} ions recombination, voltage on the bipolar membranes and the efficiency of the latter, as a transformer of chemical energy into electric, increases in the series of ionogen groups contained in the bipolar region. This is due to an increase in the recombination rate constants in the bipolar contact for the H{sup +} and OH{sup {minus}} ions. As the sodium and chlorine ions penetrate the bipolar transition region, they sharply decrease the membrane potential and the voltage drop on the bipolar membranes, because the ionogen groups turn into salt form, which is catalytically inactive in the H{sup +} and OH{sup {minus}} ions recombination reaction. It is shown that the source of current, containing the MB-24 (bipolar), MF-4sk (cation-exchange), and AMV (anion-exchange) ion-exchange membranes, has a specific power of 0.11 W/dm{sup 2} (calculated in terms of one bipolar membrane) and efficiency of 29% for 0.5 M solution of hydrochloric acid and sodium hydroxide, and 0.5 A/dm{sup 2} current density.

  3. Active region plasma outflows as sources of slow/intermediate solar wind

    NASA Astrophysics Data System (ADS)

    van Driel-Gesztelyi, Lidia M.

    2015-08-01

    L. van Driel-Gesztelyi (1,2,3), D. Baker (1), P. Démoulin (2), Culhane, J.L. (1), M.L. DeRosa (4) C.H. Mandrini (5,6), D.H. Brooks (7), A.N. Fazakerley (1), L.K. Harra (1), L. Zhao (7), T.H. Zurbuchen (7), F.A. Nuevo (5,6), A.M. Vásquez (5,6), G.D. Cristiani (5,6) M. Pick (2)1) UCL/MSSL, UK, (2) Paris Observatory, LESIA, CNRS, France, (3) Konkoly Observatory, Hungary, (4) Lockheed Martin Solar and Astrophysics Laboratory, USA, (5) IAFE, CONICET-UBA, Argentina (6) FCEN, UBA, Argentina (7) Dept. of Atmospheric, Oceanic and Earth Sciences, Univ. of Michigan, USAWe analyse plasma upflows of tens of km/s from the edges of solar active regions discovered by Hinode/EIS and investigate whether or not they become outflows, i.e. find their way into the solar wind. We analyse two magnetic configurations: bipolar and quadrupolar and find that the active region plasma may be directly channeled into the solar wind via interchange reconnection at a high-altitude null point above the active region especially when active regions are located besides coronal holes or in a more complex way via multiple reconnections even from under a closed helmet streamer. We relate the solar observations to in-situ slow/intermediate solar wind streams.

  4. ALMA OBSERVATIONS OF THE OUTFLOW FROM SOURCE I IN THE ORION-KL REGION

    SciTech Connect

    Zapata, Luis A.; Rodriguez, Luis F.; Loinard, Laurent; Schmid-Burgk, Johannes; Menten, Karl M.; Curiel, Salvador

    2012-07-20

    In this Letter, we present sensitive millimeter SiO (J = 5-4; {nu} = 0) line observations of the outflow arising from the enigmatic object Orion Source I made with the Atacama Large Millimeter/Submillimeter Array (ALMA). The observations reveal that at scales of a few thousand AU, the outflow has a marked 'butterfly' morphology along a northeast-southwest axis. However, contrary to what is found in the SiO and H{sub 2}O maser observations at scales of tens of AU, the blueshifted radial velocities of the moving gas are found to the northwest, while the redshifted velocities are in the southeast. The ALMA observations are complemented with SiO (J = 8-7; {nu} = 0) maps (with a similar spatial resolution) obtained with the Submillimeter Array. These observations also show a similar morphology and velocity structure in this outflow. We discuss some possibilities to explain these differences at small and large scales across the flow.

  5. Very low-luminosity Class I/flat outflow sources in σ Orionis

    NASA Astrophysics Data System (ADS)

    Riaz, B.; Thompson, M.; Whelan, E. T.; Lodieu, N.

    2015-01-01

    We present an optical to submillimetre multiwavelength study of two very low-luminosity Class I/flat systems, Mayrit 1701117 and Mayrit 1082188, in the σ Orionis cluster. We performed moderate-resolution (R ˜ 1000) optical (˜0.4-0.9 μm) spectroscopy with the Cassegrain Twin Spectrograph (TWIN) spectrograph at the Calar Alto 3.5-m telescope. The spectra for both sources show prominent emission in accretion- and outflow-associated lines. The mean accretion rate measured from multiple line diagnostics is 6.4 × 10-10 M⊙ yr-1 for Mayrit 1701117 and 2.5 × 10-10 M⊙ yr-1 for Mayrit 1082188. The outflow mass-loss rates for the two systems are similar and estimated to be ˜1 × 10-9 M⊙ yr-1. The activity rates are within the range observed for low-mass Class I protostars. We obtained submillimetre continuum observations with the Submillimetre Common-User Bolometer Array (SCUBA-2) bolometer at the James Clerk Maxwell Telescope. Both objects are detected at a ≥5σ level in the SCUBA-2 850-μm band. The bolometric luminosity of the targets as measured from the observed spectral energy distribution over ˜0.8-850 μm is 0.18 ± 0.04 L⊙ for Mayrit 1701117 and 0.16 ± 0.03 L⊙ for Mayrit 1082188 and is in the very low mass range. The total dust+gas mass derived from submillimetre fluxes is ˜36 MJup and ˜22 MJup for Mayrit 1701117 and Mayrit 1082188, respectively. There is the possibility that some of the envelope material might be dissipated by the strong outflows driven by these sources, resulting in a final mass of the system close to or below the substellar limit.

  6. Fossil and Nonfossil Sources of Organic and Elemental Carbon Aerosols in the Outflow from Northeast China.

    PubMed

    Zhang, Yan-Lin; Kawamura, Kimitaka; Agrios, Konstantinos; Lee, Meehye; Salazar, Gary; Szidat, Sönke

    2016-06-21

    Source quantification of carbonaceous aerosols in the Chinese outflow regions still remains uncertain despite their high mass concentrations. Here, we unambiguously quantified fossil and nonfossil contributions to elemental carbon (EC) and organic carbon (OC) of total suspended particles (TSP) from a regional receptor site in the outflow of Northeast China using radiocarbon measurement. OC and EC concentrations were lower in summer, representing mainly marine air, than in other seasons, when air masses mostly traveled over continental regions in Mongolia and northeast China. The annual-mean contribution from fossil-fuel combustion to EC was 76 ± 11% (0.1-1.3 μg m(-3)). The remaining 24 ± 11% (0.03-0.42 μg m(-3)) was attributed to biomass burning, with slightly higher contribution in the cold period (∼31%) compared to the warm period (∼21%) because of enhanced emissions from regional biomass combustion sources in China. OC was generally dominated by nonfossil sources, with an annual average of 66 ± 11% (0.5-2.8 μg m(-3)), approximately half of which was apportioned to primary biomass-burning sources (34 ± 6%). In winter, OC almost equally originated from primary OC (POC) emissions and secondary OC (SOC) formation from fossil fuel and biomass-burning sources. In contrast, summertime OC was dominated by primary biogenic emissions as well as secondary production from biogenic and biomass-burning sources, but fossil-derived SOC was the smallest contributor. Distinction of POC and SOC was performed using primary POC-to-EC emission ratios separated for fossil and nonfossil emissions. PMID:27203471

  7. Resolved atomic lines reveal outflows in two ultraluminous X-ray sources

    NASA Astrophysics Data System (ADS)

    Pinto, Ciro; Middleton, Matthew J.; Fabian, Andrew C.

    2016-05-01

    Ultraluminous X-ray sources are extragalactic, off-nucleus, point sources in galaxies, and have X-ray luminosities in excess of 3 × 1039 ergs per second. They are thought to be powered by accretion onto a compact object. Possible explanations include accretion onto neutron stars with strong magnetic fields, onto stellar-mass black holes (of up to 20 solar masses) at or in excess of the classical Eddington limit, or onto intermediate-mass black holes (103-105 solar masses). The lack of sufficient energy resolution in previous analyses has prevented an unambiguous identification of any emission or absorption lines in the X-ray band, thereby precluding a detailed analysis of the accretion flow. Here we report the presence of X-ray emission lines arising from highly ionized iron, oxygen and neon with a cumulative significance in excess of five standard deviations, together with blueshifted (about 0.2 times light velocity) absorption lines of similar significance, in the high-resolution X-ray spectra of the ultraluminous X-ray sources NGC 1313 X-1 and NGC 5408 X-1. The blueshifted absorption lines must occur in a fast-outflowing gas, whereas the emission lines originate in slow-moving gas around the source. We conclude that the compact object in each source is surrounded by powerful winds with an outflow velocity of about 0.2 times that of light, as predicted by models of accreting supermassive black holes and hyper-accreting stellar-mass black holes.

  8. Resolved atomic lines reveal outflows in two ultraluminous X-ray sources.

    PubMed

    Pinto, Ciro; Middleton, Matthew J; Fabian, Andrew C

    2016-05-01

    Ultraluminous X-ray sources are extragalactic, off-nucleus, point sources in galaxies, and have X-ray luminosities in excess of 3 × 10(39) ergs per second. They are thought to be powered by accretion onto a compact object. Possible explanations include accretion onto neutron stars with strong magnetic fields, onto stellar-mass black holes (of up to 20 solar masses) at or in excess of the classical Eddington limit, or onto intermediate-mass black holes (10(3)-10(5) solar masses). The lack of sufficient energy resolution in previous analyses has prevented an unambiguous identification of any emission or absorption lines in the X-ray band, thereby precluding a detailed analysis of the accretion flow. Here we report the presence of X-ray emission lines arising from highly ionized iron, oxygen and neon with a cumulative significance in excess of five standard deviations, together with blueshifted (about 0.2 times light velocity) absorption lines of similar significance, in the high-resolution X-ray spectra of the ultraluminous X-ray sources NGC 1313 X-1 and NGC 5408 X-1. The blueshifted absorption lines must occur in a fast-outflowing gas, whereas the emission lines originate in slow-moving gas around the source. We conclude that the compact object in each source is surrounded by powerful winds with an outflow velocity of about 0.2 times that of light, as predicted by models of accreting supermassive black holes and hyper-accreting stellar-mass black holes. PMID:27120159

  9. Auroral ion upflow and outflow: dynamics of the ionospheric source (Invited)

    NASA Astrophysics Data System (ADS)

    Zettergren, M. D.; Lynch, K. A.; Hampton, D. L.; Nicolls, M. J.; Blelly, P.; Lee, Y.; Wright, B.; Burleigh, M.

    2013-12-01

    The outflow of plasma from the auroral ionosphere to the magnetosphere is thought to be produced by a combination of physical processes. In the F-region ionosphere, plasma heating due to electric fields and precipitating particles produces bulk upflows which are capable of moving large amounts of heavy ions to high altitudes. At altitudes above where upflows are initiated, transverse ion energization by plasma waves and interaction with the auroral acceleration region can give the heavy ions sufficient energy to escape to the magnetosphere. This chain of processes is necessarily affected by the intensity and duration of the low altitude bulk upflows, in addition to any transient features. Furthermore, both chemical and perpendicular transport processes, which affect amounts and types of heavy ions available for extraction, are known to be concurrent with some bulk upflows. This work explores dynamical features of the auroral ionosphere important to the ion outflow process using a suite of 1-,2- and 3-dimensional local ionospheric models, ISR data, and optical data. The models are used to study time-dependent features of bulk upflows, including upflow buildup, propagation to higher altitudes, relaxation, composition, and hysteresis effects as a function of electric fields, precipitating particles, background densities, and thermospheric winds. Realistic modeling case studies are constructed by constraining model inputs with electric field, wind, and particle estimates derived from PFISR, FPI, and optical imager data. In addition to illustrating the highly variable nature of low altitude upflow, case studies also provide compelling evidence for the generation of molecular ions and the interplay between chemically-driven and electrodynamic density depletion processes. Finally, source populations for molecular ion outflows during geomagnetically disturbed times are examined in a statistical analysis of Sondrestrom ISR measurements. Results from these studies generally

  10. On noise sources in hot electron-degraded bipolar junction transistors

    NASA Astrophysics Data System (ADS)

    Llinares, P.; Ghibaudo, G.; Chroboczek, J. A.

    1997-09-01

    The effects of electrical stress on static characteristics and power spectral density, SIb, of base current, Ib, fluctuations at low frequencies, f<1 kHz, have been studied in quasiself-aligned bipolar n-p-n junction. In as-fabricated devices SIb∝1/AE, where AE is the transistor emitter area, whereas in strongly degraded transistors Sib∝1/PE, where PE is the transistor perimeter. The latter demonstrates directly that hot carrier-induced noise sources are generated at the periphery of the transistors, in agreement with former work on hot electron-induced aging of bipolar junction transistors.

  11. Downscattering due to Wind Outflows in Compact X-ray Sources: Theory and Interpretation

    NASA Technical Reports Server (NTRS)

    Titarchuk, Lev; Shrader, Chris

    2004-01-01

    A number of recent lines of evidence point towards the presence of hot, outflowing plasma from the central regions of compact Galactic and extragalactic X-ray sources. Additionally, it has long been noted that many of these sources exhibit an "excess" continuum component, above approx. 10 keV, usually attributed to Compton Reflection from a static medium. Motivated by these facts, as well as by recent observational constraints on the Compton reflection models - specifically apparently discrepant variability timescales for line and continuum components in some cases - we consider possible of effects of out-flowing plasma on the high-energy continuum spectra of accretion powered compact objects. We present a general formulation for photon downscattering diffusion which includes recoil and Comptonization effects due to divergence of the flow. We then develop an analytical theory for the spectral formation in such systems that allows us to derive formulae for the emergent spectrum. Finally we perform the analytical model fitting on several Galactic X-ray binaries. Objects which have been modeled with high-covering-fraction Compton reflectors, such as GS1353-64 are included in our analysis. In addition, Cyg X-3, is which is widely believed to be characterized by dense circumstellar winds with temperature of order 10(exp 6) K, provides an interesting test case. Data from INTEGRAL and RXTE covering the approx. 3 - 300 keV range are used in our analysis. We further consider the possibility that the widely noted distortion of the power-law continuum above 10 keV may in some cases be explained by these spectral softening effects.

  12. Outflows and Shock Chemistry

    NASA Astrophysics Data System (ADS)

    Tafalla, M.

    2016-05-01

    Bipolar outflows result from the supersonic ejection of material by a protostar, and constitute one of the most characteristic signposts of stellar birth. They also provide ideal targets to test chemical models, and can serve as templates for more complex systems of galactic and extragalactic astronomy where supersonic interactions between gas components take place.

  13. Continuous plasma outflows from the edge of a solar active region as a possible source of solar wind.

    PubMed

    Sakao, Taro; Kano, Ryouhei; Narukage, Noriyuki; Kotoku, Jun'ichi; Bando, Takamasa; Deluca, Edward E; Lundquist, Loraine L; Tsuneta, Saku; Harra, Louise K; Katsukawa, Yukio; Kubo, Masahito; Hara, Hirohisa; Matsuzaki, Keiichi; Shimojo, Masumi; Bookbinder, Jay A; Golub, Leon; Korreck, Kelly E; Su, Yingna; Shibasaki, Kiyoto; Shimizu, Toshifumi; Nakatani, Ichiro

    2007-12-01

    The Sun continuously expels a huge amount of ionized material into interplanetary space as the solar wind. Despite its influence on the heliospheric environment, the origin of the solar wind has yet to be well identified. In this paper, we report Hinode X-ray Telescope observations of a solar active region. At the edge of the active region, located adjacent to a coronal hole, a pattern of continuous outflow of soft-x-ray-emitting plasmas was identified emanating along apparently open magnetic field lines and into the upper corona. Estimates of temperature and density for the outflowing plasmas suggest a mass loss rate that amounts to approximately 1/4 of the total mass loss rate of the solar wind. These outflows may be indicative of one of the solar wind sources at the Sun. PMID:18063788

  14. A distance-limited sample of massive molecular outflows

    NASA Astrophysics Data System (ADS)

    Maud, L. T.; Moore, T. J. T.; Lumsden, S. L.; Mottram, J. C.; Urquhart, J. S.; Hoare, M. G.

    2015-10-01

    We have observed 99 mid-infrared-bright, massive young stellar objects and compact H II regions drawn from the Red MSX source survey in the J = 3-2 transition of 12CO and 13CO, using the James Clerk Maxwell Telescope. 89 targets are within 6 kpc of the Sun, covering a representative range of luminosities and core masses. These constitute a relatively unbiased sample of bipolar molecular outflows associated with massive star formation. Of these, 59, 17 and 13 sources (66, 19 and 15 per cent) are found to have outflows, show some evidence of outflow, and have no evidence of outflow, respectively. The time-dependent parameters of the high-velocity molecular flows are calculated using a spatially variable dynamic time-scale. The canonical correlations between the outflow parameters and source luminosity are recovered and shown to scale with those of low-mass sources. For coeval star formation, we find the scaling is consistent with all the protostars in an embedded cluster providing the outflow force, with massive stars up to ˜30 M⊙ generating outflows. Taken at face value, the results support the model of a scaled-up version of the accretion-related outflow-generation mechanism associated with discs and jets in low-mass objects with time-averaged accretion rates of ˜10-3 M⊙ yr-1 on to the cores. However, we also suggest an alternative model, in which the molecular outflow dynamics are dominated by the entrained mass and are unrelated to the details of the acceleration mechanism. We find no evidence that outflows contribute significantly to the turbulent kinetic energy of the surrounding dense cores.

  15. Interpreting observations of molecular outflow sources: the MHD shock code mhd_vode

    NASA Astrophysics Data System (ADS)

    Flower, D. R.; Pineau des Forêts, G.

    2015-06-01

    The planar MHD shock code mhd_vode has been developed in order to simulate both continuous (C) type shock waves and jump (J) type shock waves in the interstellar medium. The physical and chemical state of the gas in steady-state may also be computed and used as input to a shock wave model. The code is written principally in FORTRAN 90, although some routines remain in FORTRAN 77. The documented program and its input data are described and provided as supplementary material, and the results of exemplary test runs are presented. Our intention is to enable the interested user to run the code for any sensible parameter set and to comprehend the results. With applications to molecular outflow sources in mind, we have computed, and are making available as supplementary material, integrated atomic and molecular line intensities for grids of C- and J-type models; these computations are summarized in the Appendices. Appendix tables, a copy of the current version of the code, and of the two model grids are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/578/A63

  16. Highly supersonic bipolar mass ejection from a red giant OH/IR source - OH 0739 - 14

    SciTech Connect

    Cohen, M.; Dopita, M.A.; Schwartz, R.D.; Tielens, A.G.G.M.

    1985-10-01

    From long-slit spectrophotometry of the bipolar nebula associated with the unusual OH source, OH 0739 - 14, the presence of a blue companion to the M9 III central star was shown and a Herbig-Haro-like knot beyond each nebular lobe was discovered. From differential colors of the lobes and from radial velocities of these knots it was demonstrated that the system inclines its northern lobe in the forward direction. It was also shown that the nebulous knots are shocks being driven into an extensive circumstellar envelope, and that this material is very overabundant in nitrogen, suggesting that it is matter lost from a star of mass greater than 3 solar masses. A model of biconical ejection from a central binary is consistent with the OH observations, and a possible relation of OH 0739 - 14 to the symbiotic stars and to bipolar planetary nebulae is suggested. 42 references.

  17. Highly supersonic bipolar mass ejection from a red giant OH/IR source - OH 0739 - 14

    NASA Technical Reports Server (NTRS)

    Cohen, M.; Dopita, M. A.; Schwartz, R. D.; Tielens, A. G. G. M.

    1985-01-01

    From long-slit spectrophotometry of the bipolar nebula associated with the unusual OH source, OH 0739 - 14, the presence of a blue companion to the M9 III central star was shown and a Herbig-Haro-like knot beyond each nebular lobe was discovered. From differential colors of the lobes and from radial velocities of these knots it was demonstrated that the system inclines its northern lobe in the forward direction. It was also shown that the nebulous knots are shocks being driven into an extensive circumstellar envelope, and that this material is very overabundant in nitrogen, suggesting that it is matter lost from a star of mass greater than 3 solar masses. A model of biconical ejection from a central binary is consistent with the OH observations, and a possible relation of OH 0739 - 14 to the symbiotic stars and to bipolar planetary nebulae is suggested.

  18. Tracking Solar Active Region Outflow Plasma from its Source to the near-Earth Environment

    NASA Astrophysics Data System (ADS)

    Culhane, J. L.; Brooks, D.; Zurbuchen, T.; van Driel-Gesztelyi, L.; Fazakerley, A. N.; DeRosa, M. L.

    2012-12-01

    In a recent study of persistent active region outflow from AR 10978 in the period 10 - 15, December, 2007, Brooks and Warren (2011), using the Hinode EUV Imaging Spectrometer (EIS) instrument showed the presence of a strong low-FIP element enhancement in the outflowing plasma that was replicated three days later in the in-situ solar wind measurements made by the ACE/SWICS instrument. In the present work, we examine the outflowing plasma properties (Te, Ne, v, abundances) as a function of time in greater detail as AR 10978 passes the Earth-Sun line. The structure of the magnetic field above the two outflow regions - E and W of the AR, is also examined. Following an assessment of the relevant magnetic structures between Sun and Earth, the properties of the solar wind plasma arriving at ACE approximately three days later are measured and compared with those of the outflowing AR plasma. The relationship of these measurements to the in-situ magnetic field observed by the ACE magnetometer is also studied. Finally the role of persistent AR outflows in contributing to the slow solar wind is assessed.

  19. Time-dependent modelling of the molecular line emission from shock waves in outflow sources

    NASA Astrophysics Data System (ADS)

    Flower, D. R.; Pineau des Forêts, G.

    2012-04-01

    We have developed further the technique of time-dependent modelling of magnetohydrodynamic shock waves, with a view to interpreting the molecular line emission from outflow sources. The extensively observed source L1157 B1 was chosen as an exemplar of the application of this technique. The dynamical age of the shock wave model was varied in the range 500 ≤t≤ 5000 yr, with the best fit to the observed line intensities being obtained for t= 1000 yr; this is of the same order as the dynamical age derived by Gueth, Guilloteau & Bachiller from their observations of L1157 B1. The emission line spectra of H2, CO, SiO, ortho- and para-H2O, ortho- and para-NH3, and A- and E-type CH3OH were calculated in parallel with the dynamical and chemical parameters of the model, using the 'large velocity gradient' (LVG) approximation to the line transfer problem. We compared the predictions of the models with the observed intensities of emission lines of H2, CO, SiO, ortho-H2O, ortho-NH3 and CH3OH, which include recent Herschel satellite measurements. In the case of SiO, we show (in Appendix A) that extrapolations of the collisional rate coefficients beyond the range of kinetic temperature for which they were originally calculated lead to spurious rotational line intensities and profiles. The computed emission-line spectra of SiO, NH3 and CH3OH are shown to depend on the assumed initial composition of the grain mantles, from whence they are released, by sputtering in the shock wave, into the gas phase. The dependence of the model predictions on the adopted form of the grain-size distribution is investigated in Appendix B; the corresponding integral line intensities are given in tabular form, for a range of C-type shock speeds, in the online Supporting Information.

  20. Effect of source depth on the specificity of bipolar EEG measurements.

    PubMed

    Ryynanen, Outi; Vaisanen, Juho; Hyttinen, Jari; Malmivuo, Jaakko

    2006-01-01

    The purpose of the present study was to evaluate how the brain sources located at different depths can be most effectively measured with bipolar EEG leads. The specificity of an EEG lead to detect sources was studied with a new parameter called region of interest sensitivity ratio (ROISR) by employing a spherical head model. We studied the specificity as a function of electrode distance and further as a function of scalp:skull:brain resistivity ratio. The simulations indicate that the closer to the surface of the brain the source is located, the shorter is the interelectrode distance in the optimal lead. Also in the case of superficial sources, the small misplacement of the electrodes results in a substantial decrease in specificity. The resistivity ratio has the largest effect on the specificity, when the source is located close to the surface of the brain. However in the case of deep sources, the resistivity ratio has only minimal effect on the specificity. PMID:17945620

  1. Constraints on Asian and European sources of methane from CH4-C2H6-CO correlations in Asian outflow

    NASA Astrophysics Data System (ADS)

    Xiao, Yaping; Jacob, Daniel J.; Wang, James S.; Logan, Jennifer A.; Palmer, Paul I.; Suntharalingam, Parvadha; Yantosca, Robert M.; Sachse, Glen W.; Blake, Donald R.; Streets, David G.

    2004-08-01

    Aircraft observations of Asian outflow from the Transport and Chemical Evolution Over the Pacific (TRACE-P) aircraft mission over the NW Pacific (March and April 2001) show large CH4 enhancements relative to background, as well as strong CH4-C2H6-CO correlations that provide signatures of regional sources. We apply a global chemical transport model simulation of the CH4-C2H6-CO system for the TRACE-P period to interpret these observations in terms of CH4 sources and to explore in particular the unique constraints from the CH4-C2H6-CO correlations. We use as a priori a global CH4 source inventory constrained with National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) surface observations [Wang et al., 2004]. We find that the observed CH4 concentration enhancements and CH4-C2H6-CO correlations in Asian outflow in TRACE-P are determined mainly by anthropogenic emissions from China and Eurasia (defined here as Europe and eastern Russia), with only little contribution from tropical sources (wetlands and biomass burning). The a priori inventory overestimates the observed CH4 enhancements and shows regionally variable biases for the CH4/C2H6 slope. The CH4/CO slopes are simulated without significant bias. Matching both the observed CH4 enhancements and the CH4-C2H6-CO slopes in Asian outflow requires increasing the east Asian anthropogenic source of CH4, and decreasing the Eurasian anthropogenic source, by at least 30% for both. The need to increase the east Asian source is driven by the underestimate of the CH4/C2H6 slope in boundary layer Chinese outflow. The Streets et al. [2003] anthropogenic emission inventory for east Asia fits this constraint by increasing CH4 emissions from that region by 40% relative to the a priori, largely because of higher livestock and landfill source estimates. Eurasian sources (mostly European) then need to be reduced by 30-50% from the a priori value of 68 Tg yr-1. The decrease of

  2. A double-plasma source of continuous bipolar ion-ion beam

    SciTech Connect

    Dudin, S. V.; Rafalskyi, D. V.

    2013-01-21

    A double-plasma source capable of the generation of a continuous bipolar ion-ion beam is described. The quasi-neutral ion-ion flow to an extraction electrode is formed in the system containing primary inductively coupled plasma separated from a secondary plasma by an electrostatic grid-type filter. The total current of each ion species to the 250 mm diameter extraction electrode is about 80 mA; the electron current does not exceed 30% of the ion current. Method of positive/negative ion current ratio control is proposed, allowing the ion currents ratio variation in wide range.

  3. Seasonal variations of Asian black carbon outflow to the Pacific: Contribution from anthropogenic sources in China and biomass burning sources in Siberia and Southeast Asia

    NASA Astrophysics Data System (ADS)

    Matsui, H.; Koike, M.; Kondo, Y.; Oshima, N.; Moteki, N.; Kanaya, Y.; Takami, A.; Irwin, M.

    2013-12-01

    The Community Multiscale Air Quality model with a source and process tagged method (CMAQ/PASCAL) was used to understand source regions and types (anthropogenic (AN) and biomass burning (BB)) of Asian black carbon (BC) outflow to the Pacific during 2008 - 2010. The model simulations generally reproduced absolute concentrations and temporal (seasonal, monthly, and day-to-day) variations of BC mass concentrations, observed by both surface and aircraft measurements in outflow regions in East Asia. These model simulations show that both the total eastward flux and transport efficiency (fractions transported from sources) of BC are highest during spring (26 kg s-1 and 33% at 150E) and lowest during summer (8 kg s-1 and 20% at 150E). These seasonal variations of Asian BC outflow are generally controlled by transport patterns (monsoons, frontal passages, and convection) and emissions, from the following three sources: (1) AN emissions from China (China AN), (2) BB emissions from Southeast Asia and South China (SEA BB) during February - April, and (3) BB emissions from Siberia and Kazakhstan (Siberia BB) during April - July. In our simulations, China AN dominates the total eastward BC flux on a three-year average (61%, 17%, and 6% from China AN, Siberia BB, and SEA BB, respectively, at 150E). In contrast, SEA and Siberia BB account for 30 - 50% of the total eastward BC flux (150E and 175E) during spring and summer, and they increase the seasonal variability of the Asian BC outflow flux. BC from Siberia BB is also found to be transported to the Pacific more efficiently than BC from other sources. Although the magnitudes of BB emissions are highly uncertain, our results suggest that the control of Siberia BB will be important in terms of the trans-boundary transport of BC to the Pacific, North America, and the Arctic.

  4. Seasonal variations of Asian black carbon outflow to the Pacific: Contribution from anthropogenic sources in China and biomass burning sources in Siberia and Southeast Asia

    NASA Astrophysics Data System (ADS)

    Matsui, H.; Koike, M.; Kondo, Y.; Oshima, N.; Moteki, N.; Kanaya, Y.; Takami, A.; Irwin, M.

    2013-09-01

    The Community Multiscale Air Quality model with a source and process tagged method (CMAQ/PASCAL) was used to understand source regions and types (anthropogenic (AN) and biomass burning (BB)) of Asian black carbon (BC) outflow to the Pacific during 2008-2010. The model simulations generally reproduced absolute concentrations and temporal (seasonal, monthly, and day-to-day) variations of BC mass concentrations, observed by both surface and aircraft measurements in outflow regions in East Asia. These model simulations show that both the total eastward flux and transport efficiency (fractions transported from sources) of BC are highest during spring (26 kg s-1 and 33% at 150°E) and lowest during summer (8 kg s-1 and 20% at 150°E). These seasonal variations of Asian BC outflow are generally controlled by transport patterns (monsoons, frontal passages, and convection) and emissions from the following three sources: (1) AN emissions from China (China AN), (2) BB emissions from Southeast Asia and South China (SEA BB) during February-April, and (3) BB emissions from Siberia and Kazakhstan (Siberia BB) during April-July. In our simulations, China AN dominates the total eastward BC flux on a 3 year average (61%, 17%, and 6% from China AN, Siberia BB, and SEA BB, respectively, at 150°E). In contrast, SEA and Siberia BB account for 30-50% of the total eastward BC flux (150°E and 175°E) during spring and summer, and they increase the seasonal variability of the Asian BC outflow flux. BC from Siberia BB is also found to be transported to the Pacific more efficiently than BC from other sources. Although the magnitudes of BB emissions are highly uncertain, our results suggest that the control of Siberia BB will be important in terms of the transboundary transport of BC to the Pacific, North America, and the Arctic.

  5. Submillimeter Polarimetry of the Protostellar Outflow Sources in Serpens with the Submillimeter Common-User Bolometer Array.

    PubMed

    Davis; Chrysostomou; Matthews; Jenness; Ray

    2000-02-20

    Submillimeter polarimetric measurements of the 850 µm dust continuum emission associated with the class 0/I protostars in the Serpens dark cloud core are presented. The data are used to infer the magnetic field morphology in the region. Dust grain alignment in accretion flows and/or outflows is also briefly considered. The polarization vectors around the SMM-NW cluster of sources are more ordered than those observed near the SMM-SE cluster. Toward SMM-NW, the vectors are generally orientated north-south; between the intensity peaks in the SMM-SE region, the vectors are approximately east-west. In both regions, we suggest that the polarization pattern may be dictated by a large-scale magnetic field. We consider whether the rough northwest-southeast ridge of submillimeter sources was formed via cloud collapse along field lines that run perpendicular to this ridge. However, our data offer only very tentative support for this hypothesis. We further note that, although overall the polarization pattern in Serpens does not appear to be affected by the many outflows in the region, toward the most luminous source, SMM 1, the source of the Serpens radio jet, the vectors deviate considerably from the general pattern, instead being roughly perpendicular to the flow axis, as one would expect from a B-field oriented parallel with the flow. PMID:10655178

  6. Sources and light absorption of water-soluble organic carbon aerosols in the outflow from northern China

    NASA Astrophysics Data System (ADS)

    Kirillova, E. N.; Andersson, A.; Han, J.; Lee, M.; Gustafsson, Ö.

    2014-02-01

    High loadings of anthropogenic carbonaceous aerosols in Chinese air influence the air quality for over one billion people and impact the regional climate. A large fraction (17-80%) of this aerosol carbon is water-soluble, promoting cloud formation and thus climate cooling. Recent findings, however, suggest that water-soluble carbonaceous aerosols also absorb sunlight, bringing additional direct and indirect climate warming effects, yet the extent and nature of light absorption by this water-soluble "brown carbon" and its relation to sources is poorly understood. Here, we combine source estimates constrained by dual carbon isotopes with light-absorption measurements of water-soluble organic carbon (WSOC) for a March 2011 campaign at the Korea Climate Observatory at Gosan (KCOG), a receptor station in SE Yellow Sea for the outflow from northern China. The mass absorption cross section at 365 nm (MAC365) of WSOC for air masses from N. China were in general higher (0.8-1.1 m2 g-1), than from other source regions (0.3-0.8 m2 g-1). However, this effect corresponds to only 2-10% of the radiative forcing caused by light absorption by elemental carbon. Radiocarbon constraints show that the WSOC in Chinese outflow had significantly higher fraction fossil sources (30-50%) compared to previous findings in S. Asia, N. America and Europe. Stable carbon (δ13C) measurements were consistent with aging during long-range air mass transport for this large fraction of carbonaceous aerosols.

  7. Characterization of Molecular Outflows in the Substellar Domain

    NASA Astrophysics Data System (ADS)

    Phan-Bao, Ngoc; Lee, Chin-Fei; Ho, Paul T. P.; Dang-Duc, Cuong; Li, Di

    2014-11-01

    We report here our latest search for molecular outflows from young brown dwarfs and very low-mass stars in nearby star-forming regions. We have observed three sources in Taurus with the Submillimeter Array and the Combined Array for Research in Millimeter-wave Astronomy at 230 GHz frequency to search for CO J = 2 → 1 outflows. We obtain a tentative detection of a redshifted and extended gas lobe at about 10 arcsec from the source GM Tau, a young brown dwarf in Taurus with an estimated mass of 73 M J , which is right below the hydrogen-burning limit. No blueshifted emission around the brown dwarf position is detected. The redshifted gas lobe that is elongated in the northeast direction suggests a possible bipolar outflow from the source with a position angle of about 36°. Assuming that the redshifted emission is outflow emission from GM Tau, we then estimate a molecular outflow mass in the range from 1.9 × 10-6 M ⊙ to 2.9 × 10-5 M ⊙ and an outflow mass-loss rate from 2.7 × 10-9 M ⊙ yr-1 to 4.1 × 10-8 M ⊙ yr-1. These values are comparable to those we have observed in the young brown dwarf ISO-Oph 102 of 60 M J in ρ Ophiuchi and the very low-mass star MHO 5 of 90 M J in Taurus. Our results suggest that the outflow process in very low-mass objects is episodic with a duration of a few thousand years and the outflow rate of active episodes does not significantly change for different stages of the formation process of very low-mass objects. This may provide us with important implications that clarify the formation process of brown dwarfs.

  8. Characterization of molecular outflows in the substellar domain

    SciTech Connect

    Phan-Bao, Ngoc; Dang-Duc, Cuong; Lee, Chin-Fei; Ho, Paul T. P.; Li, Di E-mail: pbngoc@asiaa.sinica.edu.tw

    2014-11-01

    We report here our latest search for molecular outflows from young brown dwarfs and very low-mass stars in nearby star-forming regions. We have observed three sources in Taurus with the Submillimeter Array and the Combined Array for Research in Millimeter-wave Astronomy at 230 GHz frequency to search for CO J = 2 → 1 outflows. We obtain a tentative detection of a redshifted and extended gas lobe at about 10 arcsec from the source GM Tau, a young brown dwarf in Taurus with an estimated mass of 73 M {sub J}, which is right below the hydrogen-burning limit. No blueshifted emission around the brown dwarf position is detected. The redshifted gas lobe that is elongated in the northeast direction suggests a possible bipolar outflow from the source with a position angle of about 36°. Assuming that the redshifted emission is outflow emission from GM Tau, we then estimate a molecular outflow mass in the range from 1.9 × 10{sup –6} M {sub ☉} to 2.9 × 10{sup –5} M {sub ☉} and an outflow mass-loss rate from 2.7 × 10{sup –9} M {sub ☉} yr{sup –1} to 4.1 × 10{sup –8} M {sub ☉} yr{sup –1}. These values are comparable to those we have observed in the young brown dwarf ISO-Oph 102 of 60 M {sub J} in ρ Ophiuchi and the very low-mass star MHO 5 of 90 M {sub J} in Taurus. Our results suggest that the outflow process in very low-mass objects is episodic with a duration of a few thousand years and the outflow rate of active episodes does not significantly change for different stages of the formation process of very low-mass objects. This may provide us with important implications that clarify the formation process of brown dwarfs.

  9. X-RAY OUTFLOWS AND SUPER-EDDINGTON ACCRETION IN THE ULTRALUMINOUS X-RAY SOURCE HOLMBERG IX X-1

    SciTech Connect

    Walton, D. J.; Harrison, F. A.; Miller, J. M.; Reis, R. C.; Fabian, A. C.; Roberts, T. P.; Middleton, M. J.

    2013-08-10

    Studies of X-ray continuum emission and flux variability have not conclusively revealed the nature of ultraluminous X-ray sources (ULXs) at the high-luminosity end of the distribution (those with L{sub X} {>=} 10{sup 40} erg s{sup -1}). These are of particular interest because the luminosity requires either super-Eddington accretion onto a black hole of mass {approx}10 M{sub Sun} or more standard accretion onto an intermediate-mass black hole. Super-Eddington accretion models predict strong outflowing winds, making atomic absorption lines a key diagnostic of the nature of extreme ULXs. To search for such features, we have undertaken a long, 500 ks observing campaign on Holmberg IX X-1 with Suzaku. This is the most sensitive data set in the iron K bandpass for a bright, isolated ULX to date, yet we find no statistically significant atomic features in either emission or absorption; any undetected narrow features must have equivalent widths less than 15-20 eV at 99% confidence. These limits are far below the {approx}>150 eV lines expected if observed trends between mass inflow and outflow rates extend into the super-Eddington regime and in fact rule out the line strengths observed from disk winds in a variety of sub-Eddington black holes. We therefore cannot be viewing the central regions of Holmberg IX X-1 through any substantial column of material, ruling out models of spherical super-Eddington accretion. If Holmberg IX X-1 is a super-Eddington source, any associated outflow must have an anisotropic geometry. Finally, the lack of iron emission suggests that the stellar companion cannot be launching a strong wind and that Holmberg IX X-1 must primarily accrete via Roche-lobe overflow.

  10. Fast outflows in broad absorption line quasars and their connection with CSS/GPS sources

    NASA Astrophysics Data System (ADS)

    Bruni , G.; Mack, K.-H.; Montenegro-Montes, F. M.; Brienza, M.; González-Serrano, J. I.

    2016-02-01

    Broad absorption line quasars are among the objects presenting the fastest outflows. The launching mechanism itself is not completely understood. Models in which they could be launched from the accretion disk, and then curved and accelerated by the effect of the radiation pressure, have been presented. We conducted an extensive observational campaign, from radio to optical band, to collect information about their nature and test the models present in the literature, the main dichotomy being between a young scenario and an orientation one. We found a variety of possible orientations, morphologies, and radio ages, not converging to a particular explanation for the BAL phenomenon. From our latest observations in the m- and mm-band, we obtained an indication of a lower dust abundance with respect to normal quasars, thus suggesting a possible feedback process on the host galaxy. Also, in the low-frequency regime we confirmed the presence of CSS components, sometime in conjunction with a GPS one already detected at higher frequencies. Following this, about 70 % of our sample turns out to be in a GPS or CSS+GPS phase. We conclude that fast outflows, responsible for the BAL features, can be more easily present among objects going through a restarting or just-started radio phase, where radiation pressure can substantially contribute to their acceleration.

  11. Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes

    USGS Publications Warehouse

    Dohm, J.M.; Ferris, J.C.; Baker, V.R.; Anderson, R.C.; Hare, T.M.; Strom, R.G.; Barlow, N.G.; Tanaka, K.L.; Klemaszewski, J.E.; Scott, D.H.

    2001-01-01

    Paleotopographic reconstructions based on a synthesis of published geologic information and high-resolution topography, including topographic profiles, reveal the potential existence of an enormous drainage basin/aquifer system in the eastern part of the Tharsis region during the Noachian Period. Large topographic highs formed the margin of the gigantic drainage basin. Subsequently, lavas, sediments, and volatiles partly infilled the basin, resulting in an enormous and productive regional aquifer. The stacked sequences of water-bearing strata were then deformed locally and, in places, exposed by magmatic-driven uplifts, tectonic deformation, and erosion. This basin model provides a potential source of water necessary to carve the large outflow channel systems of the Tharsis and surrounding regions and to contribute to the formation of putative northern-plains ocean(s) and/or paleolakes. Copyright 2001 by the American Geophysical Union.

  12. Bipolar square-wave current source for transient electromagnetic systems based on constant shutdown time

    NASA Astrophysics Data System (ADS)

    Wang, Shilong; Yin, Changchun; Lin, Jun; Yang, Yu; Hu, Xueyan

    2016-03-01

    Cooperative work of multiple magnetic transmitting sources is a new trend in the development of transient electromagnetic system. The key is the bipolar current waves shutdown, concurrently in the inductive load. In the past, it was difficult to use the constant clamping voltage technique to realize the synchronized shutdown of currents with different peak values. Based on clamping voltage technique, we introduce a new controlling method with constant shutdown time. We use the rising time to control shutdown time and use low voltage power source to control peak current. From the viewpoint of the circuit energy loss, by taking the high-voltage capacitor bypass resistance and the capacitor of the passive snubber circuit into account, we establish the relationship between the rising time and the shutdown time. Since the switch is not ideal, we propose a new method to test the shutdown time by the low voltage, the high voltage and the peak current. Experimental results show that adjustment of the current rising time can precisely control the value of the clamp voltage. When the rising time is fixed, the shutdown time is unchanged. The error for shutdown time deduced from the energy consumption is less than 6%. The new controlling method on current shutdown proposed in this paper can be used in the cooperative work of borehole and ground transmitting system.

  13. Bipolar Disorder

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Bipolar Disorder KidsHealth > For Teens > Bipolar Disorder Print A A ... Bipolar Disorder en español Trastorno bipolar What Is Bipolar Disorder? Bipolar disorders are one of several medical conditions ...

  14. Plasma outflows at the border of active regions and the solar wind

    NASA Astrophysics Data System (ADS)

    Nuevo, F. A.; Mandrini, C. H.; Vásquez, A. M.; Deumoulin, P.; Van Driel-Gesztely, L.; Baker, D.; Cristiani, G. D.; Pick, M.; Culhane, J. L.

    We present a detailed topological analysis of active region (AR) 10978; based on a Potential Field Source Surface (PFSS) model. AR 10978 is a standard bipolar region which appears fully covered by the magnetic field lines of a coronal streamer. Despite this simple magnetic configuration; our analysis shows that it is possible for the AR plasma; contained in the outflows observed at the AR borders; to be released into the solar wind via magnetic reconnection.

  15. Effects of stellar outflows on interstellar sulfur oxide chemistry

    NASA Technical Reports Server (NTRS)

    Welch, W. J.; Vogel, S.; Terebey, S.; Dreher, J.; Jackson, J.; Carlstrom, J.

    1986-01-01

    Interferometer Maps with 2" to 6" resolution of a number of regions with active star formation (Orion A, W49, W51, SGRB2) show that the distribution of the molecule SO is very compact around stellar outflow sources. Both SO and SO2 were studied near three outflows, OrionA/IRc2 and two sources in W49. The two molecules have similar distributions and abundances. More than 95% of the emission comes from regions whose extents are only .05 to .2 pc., being larger around the more energetic sources. Their spectra are broad, 30 km/sec or more, suggesting that the oxide production is associated with the flows. The outflows are identified by water masers and by extended bipolar flows in SiO. Maps in other molecules, such as HCO+ and CS, which have similar collisional excitation requirements, have much greater spatial extent. Thus it appears that the SO and SO2 abundances are truly compact and are closely associated with the outflows.

  16. Particle Acceleration in Relativistic Outflows

    NASA Technical Reports Server (NTRS)

    Bykov, Andrei; Gehrels, Neil; Krawczynski, Henric; Lemoine, Martin; Pelletier, Guy; Pohl, Martin

    2012-01-01

    In this review we confront the current theoretical understanding of particle acceleration at relativistic outflows with recent observational results on various source classes thought to involve such outflows, e.g. gamma-ray bursts, active galactic nuclei, and pulsar wind nebulae. We highlight the possible contributions of these sources to ultra-high-energy cosmic rays.

  17. Controlling Influence of Magnetic Field on Solar Wind Outflow: An Investigation using Current Sheet Source Surface Model

    NASA Astrophysics Data System (ADS)

    Poduval, B.

    2016-08-01

    This Letter presents the results of an investigation into the controlling influence of large-scale magnetic field of the Sun in determining the solar wind outflow using two magnetostatic coronal models: current sheet source surface (CSSS) and potential field source surface. For this, we made use of the Wang and Sheeley inverse correlation between magnetic flux expansion rate (FTE) and observed solar wind speed (SWS) at 1 au. During the period of study, extended over solar cycle 23 and beginning of solar cycle 24, we found that the coefficients of the fitted quadratic equation representing the FTE–SWS inverse relation exhibited significant temporal variation, implying the changing pattern of the influence of FTE on SWS over time. A particularly noteworthy feature is an anomaly in the behavior of the fitted coefficients during the extended minimum, 2008–2010 (CRs 2073–2092), which is considered due to the particularly complex nature of the solar magnetic field during this period. However, this variation was significant only for the CSSS model, though not a systematic dependence on the phase of the solar cycle. Further, we noticed that the CSSS model demonstrated better solar wind prediction during the period of study, which we attribute to the treatment of volume and sheet currents throughout the corona and the more accurate tracing of footpoint locations resulting from the geometry of the model.

  18. A Study of Ion Outflow as a Source of Plasma for the Magnetosphere

    NASA Technical Reports Server (NTRS)

    Chappell, Charles R.

    2003-01-01

    Spacecraft measurements beginning in the early 1970 s gave indications that the ionosphere was a contributor to the energetic particle population of the Earth s magnetosphere This surprising result ran counter to the previously accepted model that the magnetospheric plasmas, because of their higher energies, must have come from the solar wind. Indeed, the original discovery of the Van Allen radiation belts, with energies of millions of electron volts, set a strong community belief in the sun as the plasma source because of the dramatic difference in the radiation belt energy and that of the Earth s ionospheric source.

  19. SURFACE AND LIGHTNING SOURCES OF NITROGEN OXIDES OVER THE UNITED STATES: MAGNITUDES, CHEMICAL EVOLUTION, AND OUTFLOW

    EPA Science Inventory

    We use observations from two aircraft during the ICARTT campaign over the eastern United States and North Atlantic during summer 2004, interpreted with a global 3-D model of tropospheric chemistry (GEOS-Chem) to test current understanding of regional sources, chemical evolution...

  20. Empirical laws of particle extraction from single-grid source of bipolar ion-electron flow

    SciTech Connect

    Dudin, S. V.; Rafalskyi, D. V.

    2012-11-15

    The present research is devoted to the problem of extraction grid choice for a single-grid source of bipolar ion-electron flow. The paper contains detailed reference information on ion and electron extraction characteristics of 10 different grids with broad range of parameters: aperture width (0.09-0.6 mm), grid transparency (0.19-0.51), thickness (0.036-0.5 mm), and with different aperture geometry. The grids with square, circular, and slit apertures were made with different technologies: laser cutting, welding, weaving, and electrolytic erosion. The general regularities of the ion and electron extraction from the single-grid source are experimentally researched for the cases of dc and RF extraction grid biasing. A conclusion has been made that the maximum extracted ion current at low ion energy (0-200 eV) does not significantly vary for all the grids and does not exceed half of the primary ion current from plasma multiplied by the optical grid transparency. The low-energy limit of efficient ion extraction has been discovered which cannot be overcome by the aperture narrowing. A conclusion is made that the RF extraction mode is superior for all the researched grids since it is characterized by higher extracted ion current at any acceleration voltage for any grid with much more simple and smooth extraction curves behavior in comparison to the dc case as well as absence of arcing, jumps, and hysteresis of the measured curves at any RF voltages. The unique ability of the RF biased single-grid source of simultaneous ion/electron emission has been studied. The measured maximal attainable ion beam current compensation ratio is always sufficiently higher than 1 and typically varies in the range 2-6. The results obtained in the present paper demonstrate prospective of the single-grid source in space thruster applications and in modern technologies, particularly for ion beam processing of wide bandgap semiconductor devices such as GaN and SiC transistors due to inherent

  1. Empirical laws of particle extraction from single-grid source of bipolar ion-electron flow.

    PubMed

    Dudin, S V; Rafalskyi, D V

    2012-11-01

    The present research is devoted to the problem of extraction grid choice for a single-grid source of bipolar ion-electron flow. The paper contains detailed reference information on ion and electron extraction characteristics of 10 different grids with broad range of parameters: aperture width (0.09-0.6 mm), grid transparency (0.19-0.51), thickness (0.036-0.5 mm), and with different aperture geometry. The grids with square, circular, and slit apertures were made with different technologies: laser cutting, welding, weaving, and electrolytic erosion. The general regularities of the ion and electron extraction from the single-grid source are experimentally researched for the cases of dc and RF extraction grid biasing. A conclusion has been made that the maximum extracted ion current at low ion energy (0-200 eV) does not significantly vary for all the grids and does not exceed half of the primary ion current from plasma multiplied by the optical grid transparency. The low-energy limit of efficient ion extraction has been discovered which cannot be overcome by the aperture narrowing. A conclusion is made that the RF extraction mode is superior for all the researched grids since it is characterized by higher extracted ion current at any acceleration voltage for any grid with much more simple and smooth extraction curves behavior in comparison to the dc case as well as absence of arcing, jumps, and hysteresis of the measured curves at any RF voltages. The unique ability of the RF biased single-grid source of simultaneous ion∕electron emission has been studied. The measured maximal attainable ion beam current compensation ratio is always sufficiently higher than 1 and typically varies in the range 2-6. The results obtained in the present paper demonstrate prospective of the single-grid source in space thruster applications and in modern technologies, particularly for ion beam processing of wide bandgap semiconductor devices such as GaN and SiC transistors due to inherent

  2. Exploring the engines of molecular outflows. Radio continuum and H_2_O maser observations.

    NASA Astrophysics Data System (ADS)

    Tofani, G.; Felli, M.; Taylor, G. B.; Hunter, T. R.

    1995-09-01

    We present A-configuration VLA observations of the 22GHz H_2_O maser line and 8.4GHz continuum emission of 22 selected CO bipolar outflows associated with water masers. These observations allow us to study the region within 10^4^AU of the engine powering the outflow. The positions of the maser spots are compared with those of ultra-compact (UC) continuum sources found in our observations, with IRAS data and with data from the literature on the molecular outflows. Weak unresolved continuum sources are found in several cases associated with the maser. Most probably they represent the ionized envelope surrounding the young stellar object (YSO) which powers the maser and the outflow. These weak radio continuum sources are not necessarily associated with the IRAS sources, which are more representative of the global emission from the star forming region. A comparison of the velocity pattern of the CO outflow with those of the maser spots detected with the VLA is also made. Asymmetries in the H_2_O velocities are found on opposite sides of the YSO, suggesting that the outflow acceleration begins from the YSO itself. In a few cases we find evidence for two outflows in different evolutionary stages. The H_2_O masers in these sources are always found at the centre of the younger outflow. The degree of variability of each maser is derived from single dish observations obtained with the Medicina radiotelescope before and after the VLA observations. Velocity drifts of some features are interpreted as acceleration of the maser.

  3. Molecular Outflows in Massive Star Forming Regions

    NASA Astrophysics Data System (ADS)

    Cunningham, Nichol

    2015-11-01

    This thesis presents millimetre continuum and molecular line observations exploring the properties of molecular outflows towards massive star forming regions. Massive stars produce some of the most energetic phenomena in the Galaxy, yet we still do not have a comprehensive understanding of how they actually form. Outflows are known to play a key role in this formation process and their properties, particularly how they change depending on the mass, luminosity and evolution of the driving source can shed light on how massive stars actually form. This thesis presents observations at both high (SMA 3 arcsecond) and low (JCMT 15 arcsecond) spatial resolution of the known jet/outflow tracers, SiO and 12CO, towards a sample massive star forming region drawn from the RMS survey. Furthermore, the presence of infall signatures is explored through observations of HCO+ and H13CO+, and the hot core nature of the regions is probed using tracers such as CH3CN, HC3N and CH3OH. SiO is detected towards approximately 50% of the massive young stellar objects and HII regions in the JCMT sample. The detection of SiO appears to be linked to the age of the RMS source, with the likely younger sources showing a stronger dependence with SiO. The presence of SiO also appears to be linked to the CO velocity, with SiO more efficiently tracing sources with higher velocity dispersions. In the MOPRA observations towards a sample of 33 RMS sources, CH3CN is detected towards 66% of the sources, with the redder likely younger sources having the largest rotational temperatures. This thesis presents the first interferometric SiO (5-4) and 12CO (2-1) observations, taken with the SMA, towards the massive star forming region G203.3166/NGC 2264-C. In this intermediate/massive star forming cluster, SiO is again tracing the youngest sources. Both the SiO and 12CO emission trace two bipolar, high velocity outflows towards the mm brightest, IR-dark, likely youngest sources in this reg! ion. In contrast the IR

  4. Episodic molecular outflow in the very young protostellar cluster Serpens South.

    PubMed

    Plunkett, Adele L; Arce, Héctor G; Mardones, Diego; van Dokkum, Pieter; Dunham, Michael M; Fernández-López, Manuel; Gallardo, José; Corder, Stuartt A

    2015-11-01

    The loss of mass from protostars, in the form of a jet or outflow, is a necessary counterpart to protostellar mass accretion. Outflow ejection events probably vary in their velocity and/or in the rate of mass loss. Such 'episodic' ejection events have been observed during the class 0 protostellar phase (the early accretion stage), and continue during the subsequent class I phase that marks the first one million years of star formation. Previously observed episodic-ejection sources were relatively isolated; however, the most common sites of star formation are clusters. Outflows link protostars with their environment and provide a viable source of the turbulence that is necessary for regulating star formation in clusters, but it is not known how an accretion-driven jet or outflow in a clustered environment manifests itself in its earliest stage. This early stage is important in establishing the initial conditions for momentum and energy transfer to the environment as the protostar and cluster evolve. Here we report that an outflow from a young, class 0 protostar, at the hub of the very active and filamentary Serpens South protostellar cluster, shows unambiguous episodic events. The (12)C(16)O (J = 2-1) emission from the protostar reveals 22 distinct features of outflow ejecta, the most recent having the highest velocity. The outflow forms bipolar lobes--one of the first detectable signs of star formation--which originate from the peak of 1-mm continuum emission. Emission from the surrounding C(18)O envelope shows kinematics consistent with rotation and an infall of material onto the protostar. The data suggest that episodic, accretion-driven outflow begins in the earliest phase of protostellar evolution, and that the outflow remains intact in a very clustered environment, probably providing efficient momentum transfer for driving turbulence. PMID:26536957

  5. Episodic molecular outflow in the very young protostellar cluster Serpens South

    NASA Astrophysics Data System (ADS)

    Plunkett, Adele L.; Arce, Héctor G.; Mardones, Diego; van Dokkum, Pieter; Dunham, Michael M.; Fernández-López, Manuel; Gallardo, José; Corder, Stuartt A.

    2015-11-01

    The loss of mass from protostars, in the form of a jet or outflow, is a necessary counterpart to protostellar mass accretion. Outflow ejection events probably vary in their velocity and/or in the rate of mass loss. Such `episodic' ejection events have been observed during the Class 0 protostellar phase (the early accretion stage), and continue during the subsequent class I phase that marks the first one million years of star formation. Previously observed episodic-ejection sources were relatively isolated; however, the most common sites of star formation are clusters. Outflows link protostars with their environment and provide a viable source of turbulence that is necessary for regulating star formation in clusters, but it is not known how an accretion-driven jet or outflow in a clustered environment manifests itself in its earliest stage. This early stage is important in establishing the initial conditions for momentum and energy transfer to the environment as the protostar and cluster evolve. Here we report that an outflow from a very young class 0 protostar, at the hub of the very active and filamentary Serpens South protostellar cluster, shows unambiguous episodic events. The 12CO (J=2-1) emission from the protostar reveals 22 distinct features of outflow ejecta, the most recent having the highest velocity. The outflow forms bipolar lobes --- one of the first detectable signs of star formation --- which originate from the peak of 1-mm continuum emission. Emission from the surrounding C18O envelope shows kinematics consistent with rotation and an infall of material onto the protostar. The data suggest that episodic accretion-driven outflow begins in the earliest phase of protostellar evolution, and that the outflow remains intact in a very clustered environment, probably providing efficient momentum transfer for driving turbulence.

  6. Surface and Lightning Sources of Nitrogen Oxides over the United States: Magnitudes, Chemical Evolution, and Outflow

    NASA Technical Reports Server (NTRS)

    Hudman, Rynda C.; Jacob, Daniel J.; Turquety, Solene; Leinbensperger, E. M.; Murray, L. T.; Wu, Samuel; Gilliland, A. B.; Avery, Melody A.; Bertram, Timothy H.; Brune, W. H.; Cohen, Ronald C.; Dibb, Jack E.; Flocke, F. M.; Fried, Alan; Holloway, J.; Neuman, J. A.; Orville, R.; Perring, Anne; Ren, Xinrong; Ryerson, T. B.; Sachse, Glen W.; Singh, H. B.; Swanson, Aaron; Wooldridge, Paul J.

    2007-01-01

    We use observations from two aircraft during the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) campaign over the eastern United States and North Atlantic during summer 2004, interpreted with a global 3-D model of tropospheric chemistry (GEOS-Chem) to test current understanding of the regional sources, chemical evolution, and export of nitrogen oxides. The boundary layer NO(x) data provide top-down verification of a 50% decrease in power plant and industry NO(x) emissions over the eastern United States between 1999 and 2004. Observed 8-12 8 km NO(x) concentrations in ICARTT were 0.55 +/- 36 ppbv, much larger than in previous United States aircraft campaigns (ELCHEM, SUCCESS, SONEX). We show that regional lightning was the dominant source of this NO(x) and increased upper tropospheric ozone by 10 ppbv. Simulating the ICARTT upper tropospheric NO(x) observations with GEOS-Chem require a factor of 4 increase in the model NO(x) yield per flash (to 500 mol/flash). Observed OH concentrations were a factor of 2 lower than can be explained from current photochemical models, and if correct would imply a broader lightning influence in the upper troposphere than presently thought.An NO(y)-CO correlation analysis of the fraction f of North American NO(x) emissions vented to the free troposphere as NO(y) (sum of NO(x) and its oxidation products PAN and HNO3) s shows observed f=16+/-10 percent and modeled f=14 +/- 8 percent, consistent with previous studies. Export to the lower free troposphere is mostly HNO3 but at higher altitudes is mostly PAN. The model successfully simulates NO(y) export efficiency and speciation, supporting previous model estimates of a large U.S. contribution to tropospheric ozone through NO(x) and PAN export.

  7. Bipolar disorder

    MedlinePlus

    Manic depression; Bipolar affective disorder; Mood disorder - bipolar; Manic depressive disorder ... Bipolar disorder affects men and women equally. It most often starts between ages 15 and 25. The exact ...

  8. Controlling Influence of Magnetic Field on Solar Wind Outflow: An Investigation using Current Sheet Source Surface Model

    NASA Astrophysics Data System (ADS)

    Poduval, Bala

    2016-05-01

    The Wang and Sheeley empirical relationship between magnetic flux tube expansion (FTE) in the inner corona and the solar wind speed (SWS) observed near the Earth's orbit forms the basis of current solar wind prediction techniques such as WSA/ENLIL. Based on this concept, the Current Sheet Source Surface (CSSS) model, built on a corona in magnetostatic equilibrium incorporating electric currents, has recently been validated for solar wind prediction. We present the initial results of an investigation of the influence of solar magnetic field in determining the solar wind outflow using the CSSS model. We found that there is significant temporal variation in the functional form of FTE--SWS relation and that the accuracy of CSSS predictions are nearly twice better than the PFSS predcitions. We attribute the greater accuracy of CSSS predictions to the model's capability to trace the solar wind sources better than the PFSS model and, perhaps, the treatment of electric currents in the inner corona in the CSSS model.Synoptic maps of coronal magnetic field, similar to the photospheric ones, are still a long way away, though techniques are under development, especially using the Coronal Multi-Channel Polarimeter data. And the near--Sun regions below 0.3 AU remain unexplored until Solar Probe Plus and Solar Orbiter are launched. A well-validated model of the corona capable of providing reliable solar wind conditions in the near-Sun region will be of great use in interpreting the data collected by these spacecraft. The magnetohydrodynamic models such as ENLIL for space weather prediction, require ambient plasma and magnetic field information at their inner boundaries, usually provided by magnetostatic models, such as PFSS, in the absence of sufficient observational data. Our present work is an attempt to provide methods to generate reliable solar wind conditions in the near-Sun region.

  9. Bipolar disorder

    MedlinePlus

    Manic depression; Bipolar affective disorder; Mood disorder - bipolar; Manic depressive disorder ... happiness and high activity or energy (mania) or depression and low activity or energy (depression). The following ...

  10. Nature or Nurture: the peculiar HH 900 jet and outflow system in the Carina nebula

    NASA Astrophysics Data System (ADS)

    Reiter, Megan; Smith, Nathan; Kiminki, Megan M.; Bally, John

    2015-01-01

    We present new optical and IR spectroscopy and Hubble Space Telescope imaging of HH 900, a peculiar protostellar outflow in the Carina nebula. Previous Hα imaging from HST revealed an unusually broad, bipolar outflow emerging from a small, tadpole-shaped globule that is illuminated by the many O-type stars in nearby Trumpler 16. Near-IR narrowband [Fe II] images reveal a symmetric, collimated jet that bisects the broad outflow traced by Hα. In a giant H II region like Carina, [Fe II] emission traces dense gas that is self-shielded from Lyman continuum photons from nearby O-type stars, but is excited by non-ionizing FUV photons that penetrate the ionization front within the jet. New Gemini AO images of near-IR H2 emission show that molecules survive in the outflow, and follow the Hα morphology. Position-velocity diagrams of the three lines also reveal very different kinematics. [Fe II] traces steady, jet-like velocities that are faster than those observed in H2 emission. Most strikingly, Hα velocities resemble the Hubble wedges seen in the position-velocity diagrams of some molecular outflows, but few other protostellar jets. We propose that [Fe II] emission traces the protostellar jet itself while H2 emission reveals the molecules that (briefly) survive in the outflow, and Hα traces the ionized skin of the outflow sheath entrained by the jet. The high estimated mass-loss rate of the jet requires a high accretion rate, implying that the unseen driving source is an intermediate-mass (~2-8 Msun) protostar. We propose that HH 900 provides a bridge between molecular outflows driven by deeply embedded sources, and jets from unobscured low-mass protostars because external irradiation from nearby O-type stars illuminates both the collimated atomic jet core and the material it sweeps up.

  11. Sources of water for the outflow channels on Mars: Implications of the Late Noachian "icy highlands" model for melting and groundwater recharge on the Tharsis rise

    NASA Astrophysics Data System (ADS)

    Cassanelli, James P.; Head, James W.; Fastook, James L.

    2015-04-01

    From the Late Noachian period, through the Hesperian, and into the Amazonian periods on Mars, large outflow channels were formed. Many are interpreted to have originated through the catastrophic discharge of groundwater from martian aquifers, involving the release of up to millions of cubic-kilometers of water. Such a mechanism for outflow channel formation requires that martian aquifers were supplied with significant quantities of water some time prior to the discharge events. Typical groundwater recharge occurs due to the infiltration of surficial waters through a permeable substrate down into aquifers. However, some climate models predict an early martian climate dominated by generally "cold and icy" conditions. In this scenario, a globally continuous, impermeable cryosphere prevents infiltration of liquid water (that might be generated at the surface through anomalous heating conditions), leaving the martian aquifers without an apparent source of recharge to supply later outflow channel formation by groundwater discharge. More recent global climate modeling of an early, thicker CO2 martian atmosphere predicts that, when coupled with a full water cycle, the atmosphere of Mars will behave adiabatically causing temperatures to decrease with elevation. The high standing areas of Mars, such as the southern highlands and the Tharsis region, then act as cold traps. This leads to the preferential accumulation of snow and ice, resulting in the formation of regional ice sheets throughout the highlands that characterize the Late Noachian "icy highlands" early Mars climate model (LNIH). We make the initial assumption that the LNIH model is representative of the early Mars climate, and seek to test the model against the presence of the Hesperian and Amazonian outflow channels to determine if it can be consistent. In order to reconcile the LNIH early Mars climate model with the presence of the later outflow channels a groundwater recharge mechanism that can operate under the

  12. High Velocity Outflows in Quasars

    NASA Astrophysics Data System (ADS)

    Hamann, Fred; Rodriguez Hidalgo, Paola; Nestor, Daniel

    2006-02-01

    High velocity (HV) outflows are important components of SMBH growth and evolution. The ability of SMBHs to accrete matter and light up as AGN probably requires that outflows are present to carry away angular momentum. Outflows during the luminous AGN phase might also play a critical role in ``unveiling" young dust-enshrouded AGN and in ``polluting" the intergalactic medium with metals at high redshifts. Nonetheless, AGN outflows remain poorly understood. We have begun a program to study a nearly unexplored realm of AGN outflow parameter space: HV winds with v> 10,000 km/s up to v~ 0.2c but small velocity dispersions (narrow absorption lines), such that v/(Delta) v ≫ 1. These extreme outflows have been detected so far in just a few quasars, but they might be ubiquitous if, as expected, the flows subtend a small solid angle as seen from the central engine. Narrow-line HV flows merit specific attention because they pose unique challenges for theoretical models of the wind acceleration, mass loss rates, launch radii, etc. They might also comprise a significant fraction of absorbers previously attributed to unrelated (interveinng) gas or galaxies. We have compiled a list of bright quasars with candidate HV outflow lines (CIV 1550 A) in existing SDSS spectra. We now propose to observe ~50 of these candidates with the 2.1m GoldCam to i) identify/confirm some of the true outflow systems (based on line variability), ii) place a firm lower limit on the fraction of quasars with narrow-line HV outflows, iii) compile a short list of confirmed HV outflow sources for future study, and iv) use the combined SDSS and GoldCam data to measure or constrain basic outflow properties, such as the kinematics, locations, and physical conditions.

  13. HST/STIS observations of the RW Aurigae bipolar jet: mapping the physical parameters close to the source

    NASA Astrophysics Data System (ADS)

    Melnikov, S. Yu; Eislöffel, J.; Bacciotti, F.; Woitas, J.; Ray, T. P.

    2009-11-01

    Context: We present the results of new spectral diagnostic investigations applied to high-resolution long-slit spectra obtained with the Hubble Space Telescope Imaging Spectrograph (HST/STIS) of the jet from the T Tauri star RW Aur. Aims: Our primary goal is to determine basic physical parameters (electron density ne and electron temperature Te, hydrogen ionisation fraction xe, total hydrogen density nH, radial velocity vr and the mass outflow rate dot Mj) along both the red- and blueshifted lobes of the RW Aur jet. Methods: The input dataset consists of seven long-slit spectra, of 0.1 arcsec spatial resolution, taken with the STIS slit parallel to the jet, and stepped across it. We use the Bacciotti & Eislöffel (1999, A&A, 342, 717) method to analyse the forbidden doublets [O I]λλ6300,6363, [S II]λλ 6716,6731, and [N II]λλ 6548,6583 Å to extract n_e, T_e, x_e, and n_H. Results: We were able to extract the parameters as far as 3.9 arcsec in the red- and 2.1 arcsec in the blueshifted beam. The electron density at the base of both lobes is close to the critical density for [S II] emission but then it decreases gradually with distance from the source. The range of electron temperatures derived for this jet (Te = 10^4-2×104 K) is similar to those generally found in other outflows from young stars. The ionisation fraction xe varies between 0.04 and 0.4, increasing within the first few arcseconds and then decreasing in both lobes. The total hydrogen density, derived as nH = ne / x_e, is on average 3.2×104 cm-3 and shows a gradual decrease along the beam. Variations of the above quantities along the jet lobes appear to be correlated with the position of knots. Combining the derived parameters with vr measured from the HST spectra and other characteristics available for this jet, we estimate dot Mj following two different procedures. The mass-outflow rate dot Mj is moderate and similar in the two lobes, despite the fact that the well-known asymmetry in the radial

  14. Helical Magnetic Fields in the NGC 1333 IRAS 4A Protostellar Outflows

    NASA Astrophysics Data System (ADS)

    Ching, Tao-Chung; Lai, Shih-Ping; Zhang, Qizhou; Yang, Louis; Girart, Josep M.; Rao, Ramprasad

    2016-03-01

    We present Submillimeter Array polarization observations of the CO J = 3-2 line toward NGC 1333 IRAS 4A. The CO Stokes I maps at an angular resolution of ˜1″ reveal two bipolar outflows from the binary sources of NGC 1333 IRAS 4A. The kinematic features of the CO emission can be modeled by wind-driven outflows at ˜20° inclined from the plane of the sky. Close to the protostars the CO polarization, at an angular resolution of ˜2.″3, has a position angle approximately parallel to the magnetic field direction inferred from the dust polarizations. The CO polarization direction appears to vary smoothly from an hourglass field around the core to an arc-like morphology wrapping around the outflow, suggesting a helical structure of magnetic fields that inherits the poloidal fields at the launching point and consists of toroidal fields at a farther distance of outflow. The helical magnetic field is consistent with the theoretical expectations for launching and collimating outflows from a magnetized rotating disk. Considering that the CO polarized emission is mainly contributed from the low-velocity and low-resolution data, the helical magnetic field is likely a product of the wind-envelope interaction in the wind-driven outflows. The CO data reveal a PA of ˜30° deflection in the outflows. The variation in the CO polarization angle seems to correlate with the deflections. We speculate that the helical magnetic field contributes to ˜10° deflection of the outflows by means of Lorentz force.

  15. Rotating molecular outflows: the young T Tauri star in CB 26

    NASA Astrophysics Data System (ADS)

    Launhardt, R.; Pavlyuchenkov, Ya.; Gueth, F.; Chen, X.; Dutrey, A.; Guilloteau, S.; Henning, Th.; Piétu, V.; Schreyer, K.; Semenov, D.

    2009-01-01

    Context: The disk-outflow connection is thought to play a key role in extracting excess angular momentum from a forming proto-star. Although jet rotation has been observed in a few objects, no rotation of molecular outflows has been unambiguously reported so far. Aims: We report new millimeter-interferometric observations of the edge-on T Tauri star - disk system in the isolated Bok globule CB 26. The aim of these observations was to study the disk-outflow relation in this 1 Myr old low-mass young stellar object. Methods: The IRAM PdBI array was used to observe 12CO(2-1) at 1.3 mm in two configurations, resulting in spectral line maps with 1.5´´ resolution. We use an empirical parameterized steady-state outflow model combined with 2-D line radiative transfer calculations and χ^2-minimization in parameter space to derive a best-fit model and constrain parameters of the outflow. Results: The data reveal a previously undiscovered collimated bipolar molecular outflow of total length ≈2000 AU, escaping perpendicular to the plane of the disk. We find peculiar kinematic signatures that suggest that the outflow is rotating with the same orientation as the disk. However, we could not ultimately exclude jet precession or two misaligned flows as possible origins of the observed peculiar velocity field. There is indirect indication that the embedded driving source is a binary system, which, together with the youth of the source, could provide a clue to the observed kinematic features of the outflow. Conclusions: CB 26 is so far the most promising source in which to study the rotation of a molecular outflow. Assuming that the outflow is rotating, we compute and compare masses, mass flux, angular momenta, and angular momentum flux of the disk and outflow and derive disk dispersal timescales of 0.5 ldots 1 Myr, comparable to the age of the system. Based on observations carried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG

  16. Coronal Pseudo-Streamer and Bipolar Streamer Observed by SOHO/UVCS in March 2008

    NASA Astrophysics Data System (ADS)

    Abbo, L.; Lionello, R.; Riley, P.; Wang, Y.-M.

    2015-07-01

    The past solar minimum is characterized by several peculiar aspects and by a complex magnetic topology with two different types of coronal streamers: pseudo-streamers and bipolar streamers. Pseudo-streamers or unipolar streamer are coronal structures that separate coronal holes of the same polarity, without a current sheet in the outer corona; unlike bipolar streamers, which separate coronal holes of opposite magnetic polarity. In this study, two examples of these structures have been identified in the period of Carrington rotation 2067 by applying a potential-field source-surface extrapolation of the photospheric field measurements. We present a spectroscopic analysis of a pseudo-streamer and a bipolar streamer observed in the period 12 - 17 March 2008 at high spectral and spatial resolution by the Ultraviolet Coronagraph Spectrometer (UVCS; Kohl et al., Solar Phys. 162, 313, 1995) onboard the Solar and Heliospheric Observatory (SOHO). The solar wind plasma parameters, such as kinetic temperature, electron density, and outflow velocity, were inferred in the extended corona (from 1.7 to ) by analyzing the O vi doublet and H i Ly line spectra. The coronal magnetic topology was taken into account and was extrapolated with a 3D magneto-hydrodynamic model of the global corona. The results of the analysis show some peculiarities of the pseudo-streamer physical parameters in comparison with those obtained for bipolar streamers: in particular, we have found a higher kinetic temperature and higher outflow velocities of O vi ions and lower electron density values. In conclusion, we point out that pseudo-streamers produce a hybrid type of outflow that is intermediate between the slow and fast solar winds. These outflows are a possible source of slow/fast wind in a non-dipolar solar magnetic field configuration.

  17. Bipolar Disorder

    MedlinePlus

    Bipolar disorder is a serious mental illness. People who have it go through unusual mood changes. They go ... The down feeling is depression. The causes of bipolar disorder aren't always clear. It runs in families. ...

  18. Disentangling the outflow and protostars in HH 900 in the Carina Nebula

    NASA Astrophysics Data System (ADS)

    Reiter, Megan; Smith, Nathan; Kiminki, Megan M.; Bally, John; Anderson, Jay

    2015-04-01

    HH 900 is a peculiar protostellar outflow emerging from a small, tadpole-shaped globule in the Carina Nebula. Previous Hα imaging with Hubble Space Telescope (HST)/Advanced Camera for Surveys showed an ionized outflow with a wide opening angle that is distinct from the highly collimated structures typically seen in protostellar jets. We present new narrowband near-IR [Fe II] images taken with the Wide Field Camera 3 on the HST that reveal a remarkably different structure than Hα. In contrast to the unusual broad Hα outflow, the [Fe II] emission traces a symmetric, collimated bipolar jet with the morphology and kinematics that are more typical of protostellar jets. In addition, new Gemini adaptive optics images reveal near-IR H2 emission coincident with the Hα emission, but not the [Fe II]. Spectra of these three components trace three separate and distinct velocity components: (1) H2 from the slow, entrained molecular gas, (2) Hα from the ionized skin of the accelerating outflow sheath, and (3) [Fe II] from the fast, dense, and collimated protostellar jet itself. Together, these data require a driving source inside the dark globule that remains undetected behind a large column density of material. In contrast, Hα and H2 emission trace the broad outflow of material entrained by the jet, which is irradiated outside the globule. As it get dissociated and ionized, it remains visible for only a short time after it is dragged into the H II region.

  19. Sublimating comets as the source of nucleation seeds for grain condensation in the gas outflow from AGB stars

    NASA Technical Reports Server (NTRS)

    Whitmire, D. P.; Matese, John J.; Reynolds, R. T.

    1989-01-01

    A growing amount of observational and theoretical evidence suggests that most main sequence stars are surrounded by disks of cometary material. The dust production by comets in such disks is investigated when the central stars evolve up the red giant and asymptotic giant branch (AGB). Once released, the dust is ablated and accelerated by the gas outflow and the fragments become the seeds necessary for condensation of the gas. The origin of the requisite seeds has presented a well known problem for classical nucleation theory. This model is consistent with the dust production observed in M giants and supergiants (which have increasing luminosities) and the fact that earlier supergiants and most WR stars (whose luminosities are unchanging) do not have significant dust clouds even though they have significant stellar winds. Another consequence of the model is that the spatial distribution of the dust does not, in general, coincide with that of the gas outflow, in contrast to the conventional condensation model. A further prediction is that the condensation radius is greater that that predicted by conventional theory which is in agreement with IR interferometry measurements of alpha-Ori.

  20. Ionospheric outflows as possible source of the low-energy plasma flux tubes controlling the dimension of pulsating auroral patches

    NASA Astrophysics Data System (ADS)

    Liang, J.; Donovan, E.; Nishimura, T.; Yang, B.; Angelopoulos, V.

    2014-12-01

    Conjunctive observations of low-Earth-orbit satellites and optical auroral imagers have indicated that, a majority of pulsating auroral patches (PAPs) are associated with low-energy ion (LEI) precipitation structures with core energies ranging from several tens of eV up to a few hundred eV. This result is consistent with a long-standing proposal that the PAPs connect to flux tubes filled with enhanced "cold" plasma. To further explore the origin and generation mechanism of those LEI structures, we investigate a few THEMIS events when the in-situ probes are conceived as conjugate to PAPs, judging by an apparent correlation between the in-situ whistler-mode chorus and the oscillation of the PAP luminosity [Nishimura et al., 2011]. We notice a common existence of LEI structures from THEMIS in-situ data during those conjugacy event intervals. Such LEI structures are always strongly field-aligned, with core energies ranging from several tens of eV up to a few hundred eV, and often exhibit distinct energy dispersion features. Contingent upon the energy range and time, the pitch-angle distribution of the LEI structures can be either heavily biased toward parallel direction, or biased toward anti-parallel direction, or roughly symmetric between parallel and anti-parallel directions. The above observations allude to the ion outflows from the ionosphere as a plausible origin of the observed LEI structures. To check the above notion, we perform particle simulations assuming that the low-energy ions originate from the ion outflows in topside ionosphere and bounce between hemispheres while convecting with EXB drift. The simulation results can reproduce some of the basic observable features of the LEI structures, such as the energy dispersion and the variation of pitch-angle distribution versus time and energy. Combining the results from low-Earth-orbit satellites observations, THEMIS in-situ observations, and simulations, we propose that the ion outflows into the magnetosphere

  1. XMM Observations of Two Quadrupolar Outflows

    NASA Astrophysics Data System (ADS)

    Simon, Theodore

    2009-03-01

    X-ray images of two small dark clouds, L1455 and L723, have been obtained with the EPIC cameras on board the XMM-Newton telescope. Both regions contain multiple independent but overlapping bipolar flows in high-velocity CO, a collection of Herbig-Haro objects, and a number of filaments and knots of H2 emission. The field of view in each cloud was centered on the confluence of the nearly orthogonal CO flows. More than three dozen compact X-ray sources were detected. However, the Class 0/I protostars thought to be the driving sources of the flows in both clouds were not detected. Strong emission was observed from RNO 15, an optically visible, nebulous T Tauri star in the dense core of L1455. A thermal plasma model for the X-ray spectrum of RNO 15 gave a luminosity of L X ~ 1031.2 erg s-1. The heavily reddened Class II star L1455 IRS 5 in the same region was detected as a weak X-ray source. No emission was detected from IRS 1 or IRS 4, which have been suggested as the launch sites for separate outflows in L1455. X-ray emission was observed from IRAS 19156+1906 in L723. The thermal radio source VLA 2, which is offset ~10'' east of the IRAS position and is considered the most likely energy source for the strong east-west flow in L723, was not detected. The source of the more narrowly collimated north-south flow in L723 is unknown but may be an embedded infrared object at the X-ray and IRAS position.

  2. Very low-luminosity Class I/Flat outflow sources in sigma Orionis: Clues to alternative formation mechanisms for very low-mass stars

    NASA Astrophysics Data System (ADS)

    Riaz, Basmah; Whelan, E.; Thompson, M.; Vorobyov, E.; Lodieu, N.

    2015-01-01

    We present an optical through sub-millimetre multi-wavelength study of two very low-luminosity Class I/Flat systems, Mayrit 1701117 and Mayrit 1082188, in the sigma Orionis cluster. We performed moderate resolution (R 1000) optical ( 0.4-0.9mu) spectroscopy with the TWIN spectrograph at the Calar Alto 3.5-m telescope. The spectra for both sources show prominent emission in accretion- and outflow-associated lines. The mean accretion rate measured from multiple line diagnostics is 6.4x10^{-10} Msun/yr for Mayrit 1701117, and 2.5x10^{-10} Msun/yr for Mayrit 1082188. The outflow mass loss rates for the two systems are similar and estimated to be 1x10^{-9} Msun/yr. The activity rates are within the range observed for low-mass Class I protostars. We obtained sub-millimetre continuum observations with the Submillimetre Common-User Bolometer Array (SCUBA-2) bolometer at the James Clerk Maxwell Telescope. Both objects are detected at a >5-sigma level in the SCUBA-2 850mu band. The bolometric luminosity of the targets as measured from the observed spectral energy distribution over 0.8-850mu is 0.18+/-0.04 Lsun for Mayrit 1701117, and 0.16+/-0.03 Lsun for Mayrit 1082188, and is in the very low-mass range. The total dust+gas mass derived from sub-millimetre fluxes is 36 M_Jup and 22 M_Jup for Mayrit 1701117 and Mayrit 1082188, respectively. There is the possibility that some of the envelope material might be dissipated by the strong outflows driven by these sources, resulting in a final mass of the system close to or below the sub-stellar limit. Given the membership of these objects in a relatively evolved cluster of 3 Myr of age, we consider an alternate formation mechanism in the context of the `hybrid' model of disk fragmentation, followed by ejection of a gaseous clump.

  3. Coronal hole boundaries evolution at small scales. II. XRT view. Can small-scale outflows at CHBs be a source of the slow solar wind

    NASA Astrophysics Data System (ADS)

    Subramanian, S.; Madjarska, M. S.; Doyle, J. G.

    2010-06-01

    Aims: We aim to further explore the small-scale evolution of coronal hole boundaries using X-ray high-resolution and high-cadence images. We intend to determine the fine structure and dynamics of the events causing changes of coronal hole boundaries and to explore the possibility that these events are the source of the slow solar wind. Methods: We developed an automated procedure for the identification of transient brightenings in images from the X-ray telescope on-board Hinode taken with an Al Poly filter in the equatorial coronal holes, polar coronal holes, and the quiet Sun with and without transient coronal holes. Results: We found that in comparison to the quiet Sun, the boundaries of coronal holes are abundant with brightening events including areas inside the coronal holes where closed magnetic field structures are present. The visual analysis of these brightenings revealed that around 70% of them in equatorial, polar and transient coronal holes and their boundaries show expanding loop structures and/or collimated outflows. In the quiet Sun only 30% of the brightenings show flows with most of them appearing to be contained in the solar corona by closed magnetic field lines. This strongly suggests that magnetic reconnection of co-spatial open and closed magnetic field lines creates the necessary conditions for plasma outflows to large distances. The ejected plasma always originates from pre-existing or newly emerging (at X-ray temperatures) bright points. Conclusions: The present study confirms our findings that the evolution of loop structures known as coronal bright points is associated with the small-scale changes of coronal hole boundaries. The loop structures show an expansion and eruption with the trapped plasma consequently escaping along the “quasi” open magnetic field lines. These ejections appear to be triggered by magnetic reconnection, e.g. the so-called interchange reconnection between the closed magnetic field lines (BPs) and the open

  4. Bipolar Disorder.

    ERIC Educational Resources Information Center

    Spearing, Melissa

    Bipolar disorder, a brain disorder that causes unusual shifts in a person's mood, affects approximately one percent of the population. It commonly occurs in late adolescence and is often unrecognized. The diagnosis of bipolar disorder is made on the basis of symptoms, course of illness, and when possible, family history. Thoughts of suicide are…

  5. Bipolar Disorder

    MedlinePlus

    ... or digestive problems Problems sleeping, or wanting to sleep all of the time Feeling tired all of the time Thoughts about death and suicide Causes & Risk Factors What causes bipolar disorder? Bipolar disorder may be caused by a chemical imbalance in the brain. It sometimes runs in ...

  6. Bipolar disorder.

    PubMed

    Grande, Iria; Berk, Michael; Birmaher, Boris; Vieta, Eduard

    2016-04-01

    Bipolar disorder is a recurrent chronic disorder characterised by fluctuations in mood state and energy. It affects more than 1% of the world's population irrespective of nationality, ethnic origin, or socioeconomic status. Bipolar disorder is one of the main causes of disability among young people, leading to cognitive and functional impairment and raised mortality, particularly death by suicide. A high prevalence of psychiatric and medical comorbidities is typical in affected individuals. Accurate diagnosis of bipolar disorder is difficult in clinical practice because onset is most commonly a depressive episode and looks similar to unipolar depression. Moreover, there are currently no valid biomarkers for the disorder. Therefore, the role of clinical assessment remains key. Detection of hypomanic periods and longitudinal assessment are crucial to differentiate bipolar disorder from other conditions. Current knowledge of the evolving pharmacological and psychological strategies in bipolar disorder is of utmost importance. PMID:26388529

  7. The Structure and Environmental Impacts of Protostellar Outflows in DR 21 and Orion

    NASA Astrophysics Data System (ADS)

    Wiseman, J. J.; Ho, P. T. P.; Brown, R.

    1997-12-01

    Regions of high-mass star formation are considerably more complicated than their low-mass counterparts. Recent HST NICMOS images of Orion-KL (Thompson et al. 1997) as well as sensitive ground-based infrared images of H_2 shock emission in the Orion outflow region (Chrysostomou et al. 1997, McCaughrean & Mac Low 1997, Schild et al. 1997) reveal intricate clumpy shock structures extending in nearly all radial directions from the source. The one radial direction in which the shock emission is particularly diminished is to the northeast, and it is precisely here that a molecular gas filament is present and highly heated, as though blocking the path of outflowing material from Orion-KL. We present our latest NH_3 (1,1), (2,2), and (3,3) VLA MEM mosaics of the Orion-KL region. We present evidence from temperature and chemical excitation gradients that the molecular gas cores along the filament extending to the northeast of Orion-KL are strongly heated by impacts from protostellar ejecta. These effects are seen in the core ``CS1'' 30'' northeast of IRc2 and also in cores at least twice as distant (1.5 pc). The DR 21 outflow region is also quite complex, with multiple molecular outflows extending from a multiple-component HII region. We present sensitive VLA maps of hydrogen recombination line emission, and we report the detection of bipolar ionized gas within the molecular outflow lobes. This detection gives observational evidence for the initial ionized inner structure of high mass protostellar outflows. Chrysostomou, A. et al. 1997, MNRAS, 289, 605 McCaughrean, M., & Mac Low, M.-M. 1997, AJ, 113, 391 Schild, H., Miller, S., & Tennyson, J. 1997, A&A, 319, 1037 Thompson, R., Rieke, M., Schneider, G., Stolovy, S., Erickson, E., & Axon, D. 1997, STSCI Early Release Observation PRC97-13

  8. Sources, solubility, and acid processing of aerosol iron and phosphorous over the South China Sea: East Asian dust and pollution outflows vs. Southeast Asian biomass burning

    NASA Astrophysics Data System (ADS)

    Hsu, S.-C.; Gong, G.-C.; Shiah, F.-K.; Hung, C.-C.; Kao, S.-J.; Zhang, R.; Chen, W.-N.; Chen, C.-C.; Chou, C. C.-K.; Lin, Y.-C.; Lin, F.-J.; Lin, S.-H.

    2014-08-01

    Iron and phosphorous are essential to marine microorganisms in vast regions in oceans worldwide. Atmospheric inputs are important allochthonous sources of Fe and P. The variability in airborne Fe deposition is hypothesized to serve an important function in previous glacial-interglacial cycles, contributing to the variability in atmospheric CO2 and ultimately the climate. Understanding the mechanisms underlying the mobilization of airborne Fe and P from insoluble to soluble forms is critical to evaluate the biogeochemical effects of these elements. In this study, we present a robust power-law correlation between fractional Fe solubility and non-sea-salt-sulfate / Total-Fe (nss-sulfate / FeT) molar ratio independent of distinct sources of airborne Fe of natural and/or anthropogenic origins over the South China Sea. This area receives Asian dust and pollution outflows and Southeast Asian biomass burning. This correlation is also valid for nitrate and total acids, demonstrating the significance of acid processing in enhancing Fe mobilization. Such correlations are also found for P, yet source dependent. These relationships serve as straightforward parameters that can be directly incorporated into available atmosphere-ocean coupling models that facilitate the assessment of Fe and P fertilization effects. Although biomass burning activity may supply Fe to the bioavailable Fe pool, pyrogenic soils are possibly the main contributors, not the burned plants. This finding warrants a multidisciplinary investigation that integrates atmospheric observations with the resulting biogeochemistry in the South China Sea, which is influenced by atmospheric forcings and nutrient dynamics with monsoons.

  9. SIO Emission in the Multilobe Outflow Associated with IRAS 16293-2422

    NASA Astrophysics Data System (ADS)

    Hirano, Naomi; Mikami, Hitomi; Umemoto, Tomofumi; Yamamoto, Satoshi; Taniguchi, Yoshiaki

    2001-02-01

    We have mapped the thermal emission line of SiO (v=0; J=2-1) associated with the quadrupolar molecular outflow driven by the very cold far-infrared source IRAS 16293-2422. The SiO emission is significantly enhanced in the northeastern red lobe and at the position ~50" east of the IRAS source. Strong SiO emission observed at ~50" east of the IRAS source presents evidence for a dynamical interaction between a part of the eastern blue lobe and the dense ambient gas condensation; however, such an interaction is unlikely to be responsible for producing the quadrupolar morphology. The SiO emission in the northeastern red lobe shows spatial and velocity structure similar to those of the CO outflow, suggesting that the SiO emission comes from the molecular outflow in the northeastern red lobe itself. The observed velocity structure is reproduced by a simple spatiokinematic model of bow shock with a shock velocity of 19-24 km s-1 inclined by 30°-45° from the plane of the sky. This implies that the northeastern red lobe is independent of the eastern blue lobe and that the quadrupolar structure is due to two separate bipolar outflows. The SiO emission observed in the western red lobe has a broad pedestal shape with low intensity. Unlike the SiO emission in the northeastern red lobe, the spatial extent of the SiO emission in the western red lobe is restricted to its central region. The spatial and velocity structures and the line profiles suggest that three different types of SiO emission are observed in this outflow: the SiO emission arising from the interface between the outflowing gas and the dense ambient gas clump, the SiO emission coming from the outflow lobe itself, and the broad SiO emission with low intensity observed at the central region of the outflow lobe. Based on observations made at the Nobeyama Radio Observatory (NRO). Nobeyama Radio Observatory is a branch of the National Astronomical Observatory of Japan, an interuniversity research institute operated by

  10. Bipolar Disorder

    MedlinePlus

    ... health professional before making a commitment. Learn More Free Booklets and Brochures Bipolar Disorder: A brochure on ... in the public domain and available for use free of charge. Citation of the NIMH is appreciated. ...

  11. Bipolar battery

    DOEpatents

    Kaun, Thomas D.

    1992-01-01

    A bipolar battery having a plurality of cells. The bipolar battery includes: a negative electrode; a positive electrode and a separator element disposed between the negative electrode and the positive electrode, the separator element electrically insulating the electrodes from one another; an electrolyte disposed within at least one of the negative electrode, the positive electrode and the separator element; and an electrode containment structure including a cup-like electrode holder.

  12. THE CIRCUMBINARY OUTFLOW: A PROTOSTELLAR OUTFLOW DRIVEN BY A CIRCUMBINARY DISK

    SciTech Connect

    Machida, Masahiro N.; Inutsuka, Shu-ichiro; Matsumoto, Tomoaki E-mail: inutsuka@nagoya-u.j

    2009-10-10

    Protostellar outflow is a star's first cry at the moment of birth. The outflows have an indispensable role in the formation of single stars because they carry off the excess angular momentum from the center of the shrinking gas cloud, and permit further collapse to form a star. On the other hand, a significant fraction of stars is supposedly born as binaries with circumbinary disks that are frequently observed. Here, we investigate the evolution of a magnetized rotating cloud using a three-dimensional resistive MHD nested-grid code, and show that the outflow is driven by the circumbinary disk and has an important role even in the binary formation. After the adiabatic core formation in the collapsing cloud core, the magnetic flux is significantly removed from the center of the cloud by the Ohmic dissipation. Since this removal makes the magnetic braking ineffective, the adiabatic core continuously acquires the angular momentum to induce fragmentation and subsequent binary formation. The magnetic field accumulates in the circumbinary disk where the removal and accretion of magnetic field are balanced, and finally drives the circumbinary outflow. This result explains the spectacular morphology of some specific young stellar objects such as L1551 IRS5. We can infer that most of the bipolar molecular outflows observed by low density tracers (i.e., CO) would correspond to circumbinary or circum-multiple outflows found in this Letter, since most of the young stellar objects are supposed to be binaries or multiples.

  13. CLASSICAL T TAURI-LIKE OUTFLOW ACTIVITY IN THE BROWN DWARF MASS REGIME

    SciTech Connect

    Whelan, E. T.; Ray, T. P.; Podio, L.; Bacciotti, F.; Randich, S.

    2009-12-01

    Over the last number of years, spectroscopic studies have strongly supported the assertion that protostellar accretion and outflow activity persist to the lowest masses. Indeed, previous to this work, the existence of three brown dwarf (BD) outflows had been confirmed by us. In this paper, we present the results of our latest investigation of BD outflow activity and report on the discovery of two new outflows. Observations to date have concentrated on studying the forbidden emission line (FEL) regions of young BDs and in all cases data have been collected using the UV-Visual Echelle Spectrometer (UVES) on the ESO Very Large Telescope. Offsets in the FEL regions are recovered using spectro-astrometry. Here, ISO-Oph 32 is shown to drive a blueshifted outflow with a radial velocity of 10-20 km s{sup -1} and spectro-astrometric analysis constrains the position angle of this outflow to 240{sup 0} +- 7{sup 0}. The BD candidate, ISO-ChaI 217 is found to have a bipolar outflow bright in several key forbidden lines (V{sub RAD} = -20 km s{sup -1}, +40 km s{sup -1}) and with a P.A. of 193{sup 0}-209{sup 0}. A striking feature of the ISO-ChaI 217 outflow is the strong asymmetry between the red- and blueshifted lobes. This asymmetry is revealed in the relative brightness of the two lobes (redshifted lobe is brighter), the factor of 2 difference in radial velocity (the redshifted lobe is faster) and the difference in the electron density (again higher in the red lobe). Such asymmetries are common in jets from low-mass protostars and the observation of a marked asymmetry at such a low mass (<0.1 M{sub sun}) supports the idea that BD outflow activity is scaled down from low-mass protostellar activity. Also note that although asymmetries are unexceptional, it is uncommon for the redshifted lobe to be the brightest as some obscuration by the accretion disk is assumed. This phenomenon has only been observed in one other source, the classical T Tauri (CTTS) star RW Aur. The physical

  14. Tracking sources of severe haze episodes and their physicochemical and hygroscopic properties under Asian continental outflow: Long-range transport pollution, postharvest biomass burning, and Asian dust

    NASA Astrophysics Data System (ADS)

    Jung, Jinsang; Kim, Young J.

    2011-01-01

    Aerosol physicochemical and hygroscopic properties were measured from 12 October to 21 November 2005 at a downwind area of the Asian continental outflow (Gwangju, Korea) to characterize severe haze episodes. Using optically measured elemental carbon (EC) at 660 nm (Opt.EC) and 880 nm (BC) wavelengths and Mie theory, it was estimated that the higher BC/Opt.EC ratio during the cloudy day of the long-range transport (LTP) period was mainly due to EC particle growth from in-cloud processing with secondary aerosols such as sulfate and organic aerosols. Single scattering albedo (SSA) of biomass burning (BB) aerosol increased sharply from 0.89 to 0.94 under a relative humidity >70%, suggesting that organic aerosols emitted from rice straw burning contained high amounts of hydrophilic compounds. The contribution of aerosol water content to the total light extinction coefficient (bext) was determined as 51.4% and 68.4% during the BB and BB + LTP periods, respectively, indicating that the haze episodes were highly enhanced by an increase in aerosol water content. The Asian dust event was characterized by the highest SSA (0.92 ± 0.02), the lowest mass scattering efficiency of fine particles (2.5 ± 1.0 m2 g-1), and the lowest hygroscopic nature (humidity-dependent light scattering enhancement factor, f(80%), which is defined by the ratio of light scattering coefficient at 80% relative humidity to that at dry condition, = ˜1.37). Based on the Ångström exponent (α) values observed at the source region of the Asian continent and the downwind area of South Korea during the BB + LTP period, it was found that the α value of urban aerosols decreased ˜11% for 1-2 days of the transport, probably due to the increase in particle size through water uptake. Increasing rates of surface PM10 mass concentrations at western coastal areas of the South Korean peninsula were in the range 2.4-14.4 μgm-3 h-1 at the beginning of the BB + LTP period (24 October 2005, 0700-2300 LT). Based on

  15. Infrared polarization images of star-forming regions. I - The ubiquity of bipolar structure

    NASA Technical Reports Server (NTRS)

    Tamura, M.; Gatley, Ian; Joyce, R. R.; Ueno, M.; Suto, H.; Sekiguchi, M.

    1991-01-01

    The inefficiency of the stellar formation process leads rather generally to high residual dust densities, and so to the existence of infrared reflection nebulosity (IRN), in regions of star formation. Polarization images of several star-forming regions with mass outflows (GSS 30, S255, GL 5180, GL 2591, GGD 27, and NGC 7538) presented here: (1) establish the universality of bipolarity and of shell or cavity structure in the IRN consistent with that of CO outflow; (2) identify the source of the mass outflow in each case; (3) show that the opening angle near this central source is large; and (4) demonstrate several instances of multiple shells, probably arising from episodic mass loss. Astrometry of 2.2-micron sources with arcsecond accuracy identifies the illuminating source of each IRN uniquely with a compact H II region or a bright IR source. The polarization images provide strong evidence for large-scale dust toroids around each of these sources. The density and mass of these disks are estimated from the extinction through the disk.

  16. Bipolar disorder

    PubMed Central

    Goodwin, Frederick K.; Ghaemi, S. Nassir

    1999-01-01

    Bipolar disorder's unique combination of three characteristics - clear genetic diathesis, distinctive clinical features, early availability of an effective treatment (lithium) - explains its special place in the history of psychiatry and its contribution to the current explosive growth of neuroscience. This article looks at the state of the art in bipolar disorder from the vantage point of: (i) genetics (possible linkages on chromosomes 18 and 21q, polygenic hypothesis, research into genetic markers); (ii) diagnosis (new focus on the subjective aspects of bipolar disorder to offset the current trend of underdiagnosis due to overreliance on standardized interviews and rating scales); (iii) outcome (increase in treatment-resistant forms signaling a change in the natural history of bipolar disorder); (iv) pathophysiology (research into circadian biological rhythms and the kindling hypothesis to explain recurrence); (v) treatment (emergence of the anticonvulsants, suggested role of chronic antidepressant treatment in the development of treatment resistance); (vi) neurobiology (evaluation of regulatory function in relation to affective disturbances, role of postsynaptic second-messenger mechanisms, advances in functional neuroimaging); and (vii) psychosocial research (shedding overly dualistic theories of the past to understand the mind and brain as an entity, thus emphasizing the importance of balancing the psychopharmacological and psychotherapeutic approaches). Future progress in the understanding and treatment of bipolar disorder will rely on successful integration of the biological and psychosocial lines of investigation. PMID:22033232

  17. The resolved outflow from 3C 48

    SciTech Connect

    Shih, Hsin-Yi; Stockton, Alan E-mail: stockton@ifa.hawaii.edu

    2014-10-20

    We investigate the properties of the high-velocity outflow driven by the young radio jet of 3C 48, a compact-steep-spectrum source. We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telecope to obtain (1) low-resolution UV and optical spectra and (2) multi-slit medium-resolution spectra of the ionized outflow. With supporting data from ground-based spectrographs, we are able to accurately measure the ratios of diagnostic emission lines such as [O III] λ5007, [O III] λ3727, [N II] λ6548, Hα, Hβ, [Ne V] λ3425, and [Ne III] λ3869. We fit the observed emission-line ratios using a range of ionization models, powered by active galactic nucleus (AGN) radiation and shocks, produced by the MAPPINGS code. We have determined that AGN radiation is likely the dominant ionization source. The outflow's density is estimated to be in the range n = 10{sup 3}-10{sup 4} cm{sup –3}, the mass is ∼6 × 10{sup 6} M {sub ☉}, and the metallicity is likely equal to or higher than solar. Compared with the typical outflows associated with more evolved radio jets, this young outflow is denser, less massive, and more metal rich. Multi-slit observations allow us to construct a two-dimensional velocity map of the outflow that shows a wide range of velocities with distinct velocity components, suggesting a wide-angle clumpy outflow.

  18. Outflow Detection in a 70 μm Dark High-Mass Core

    NASA Astrophysics Data System (ADS)

    Feng, Siyi; Beuther, Henrik; Zhang, Qizhou; Liu, Hauyu Baobab; Zhang, Zhiyu; Wang, Ke; Qiu, Keping

    2016-09-01

    We present observations toward a high-mass (\\gt 40 {M}ȯ ), low-luminosity (\\lt 10 {L}ȯ ) 70 μ {{m}} dark molecular core G28.34 S-A at 3.4 mm, using the IRAM 30 m telescope and the NOEMA interferometer. We report the detection of {SiO} J=2\\to 1 line emission, which is spatially resolved in this source at a linear resolution of ∼0.1 pc, while the 3.4 mm continuum image does not resolve any internal sub-structures. The SiO emission exhibits two W–E oriented lobes centering on the continuum peak. Corresponding to the redshifted and blueshifted gas with velocities up to 40 {km} {{{s}}}-1 relative to the quiescent cloud, these lobes clearly indicate the presence of a strong bipolar outflow from this 70 μ {{m}} dark core, a source previously considered as one of the best candidates of “starless” core. Our SiO detection is consistent with ALMA archival data of {SiO} J=5\\to 4, whose high-velocity blueshifted gas reveals a more compact lobe spatially closer to the dust center. This outflow indicates that the central source may be in an early evolutionary stage of forming a high-mass protostar. We also find that the low-velocity components (in the range of {{Vlsr}}-5+3 {km} {{{s}}}-1) have an extended, NW–SE oriented distribution. Discussing the possible accretion scenarios of the outflow-powering young stellar object, we argue that molecular line emission and the molecular outflows may provide a better indication of the accretion history of the forming young stellar object, than snapshot observations of the present bolometric luminosity. This is particularly significant for cases of episodic accretion, which may occur during the collapse of the parent molecular core.

  19. Outflow Driven Turbulence in Star Forming Clouds

    NASA Astrophysics Data System (ADS)

    Frank, Adam

    Setting young stellar object jets and outflows in their broadest context requires an understanding of outflows as “feedback” in the development of molecular cloud turbulence and the determination of star formation efficiencies. In this contribution I review our group’s recent studies exploring relationships between protostellar outflows and turbulence in molecular clouds. We first present studies of turbulence and fossil cavities driven by YSO outflows using numerical simulations which track the evolution of single transient jets driven into a turbulent medium. Our simulations show both the effect of turbulence on outflow structures and, conversely, the effect of outflows on the ambient turbulence. These studies demonstrate that individual transient outflows have the capacity to re-energize decaying turbulence. Next we present simulations of multiple interacting jets. We show that turbulence can readily be sustained by these interactions and show that it is possible to broadly characterize an effective driving scale of the outflows. Comparing the velocity spectrum obtained in our studies to that of an isotropically forced control we show that in outflow driven turbulence a power law of the form E(k) ∝ k - β is indeed achieved. However we find a steeper spectrum β ˜ 3 is obtained in outflow driven turbulence models than in isotropically forced simulations β ˜ 2. 0. Taken together both studies provide broad support for the conclusion that fossil cavities driven by decaying jets can provide a source of turbulence and feedback which mediate star formation processes in molecular clouds. Whether this does obtain in real clouds remains a point which must be demonstrated

  20. Bipolar Disorder

    MedlinePlus

    ... might cause your mood changes. If not treated, bipolar disorder can lead to damaged relationships, poor job or school performance, and even suicide. However, there are effective treatments to control symptoms: medicine and talk therapy. A combination usually works best. NIH: National Institute ...

  1. SMA submillimeter observations of HL Tau: revealing a compact molecular outflow

    SciTech Connect

    Lumbreras, Alba M.; Zapata, Luis A.

    2014-04-01

    We present archival high angular resolution (∼2'') {sup 12}CO(3-2) line and continuum submillimeter observations of the young stellar object HL Tau made with the Submillimeter Array. The {sup 12}CO(3-2) line observations reveal the presence of a compact and wide opening angle bipolar outflow with a northeast to southwest orientation (P.A. = 50°) that is associated with the optical and infrared jet emanating from HL Tau with a similar orientation. On the other hand, the 850 μm continuum emission observations exhibit a strong and compact source in the position of HL Tau that has a spatial size of ∼200 × 70 AU with a P.A. = 145° and a dust mass of around 0.1 M {sub ☉}. These physical parameters are in agreement with values obtained recently from millimeter observations. This submillimeter source is therefore related to the disk surrounding HL Tau.

  2. Tracing outflows in the AGN forbidden region with SINFONI

    NASA Astrophysics Data System (ADS)

    Kakkad, D.; Mainieri, V.; Padovani, P.; Cresci, G.; Husemann, B.; Carniani, S.; Brusa, M.; Lamastra, A.; Lanzuisi, G.; Piconcelli, E.; Schramm, M.

    2016-08-01

    Context. Active galactic nucleus (AGN) driven outflows are invoked in numerical simulations to reproduce several observed properties of local galaxies. The z > 1 epoch is of particular interest as it was during this time that the volume averaged star formation and the accretion rate of black holes were at their maximum. Radiatively driven outflows are therefore believed to be common during this epoch. Aims: We aim to trace and characterize outflows in AGN hosts with high mass accretion rates at z > 1 using integral field spectroscopy. We obtain spatially resolved kinematics of the [O iii] λ5007 line in two targets which reveal the morphology and spatial extension of the outflows. Methods: We present SINFONI observations in the J band and the H + K band of five AGNs at 1.2 < z < 2.2. To maximize the chance of observing radiatively driven outflows, our sample was pre-selected based on peculiar values of the Eddington ratio and the hydrogen column density of the surrounding interstellar medium. We observe high velocity (~600-1900 km s-1) and kiloparsec scale extended ionized outflows in at least three of our targets, using [O iii] λ5007 line kinematics tracing the AGN narrow line region. We estimate the total mass of the outflow, the mass outflow rate, and the kinetic power of the outflows based on theoretical models and report on the uncertainties associated with them. Results: We find mass outflow rates of ~1-10 M⊙/yr for the sample presented in this paper. Based on the high star formation rates of the host galaxies, the observed outflow kinetic power, and the expected power due to the AGN, we infer that both star formation and AGN radiation could be the dominant source for the outflows. The outflow models suffer from large uncertainties, hence we call for further detailed observations for an accurate determination of the outflow properties to confirm the exact source of these outflows.

  3. PROTOSTELLAR OUTFLOWS AND RADIATIVE FEEDBACK FROM MASSIVE STARS

    SciTech Connect

    Kuiper, Rolf; Yorke, Harold W.; Turner, Neal J. E-mail: Harold.W.Yorke@jpl.nasa.gov

    2015-02-20

    We carry out radiation hydrodynamical simulations of the formation of massive stars in the super-Eddington regime including both their radiative feedback and protostellar outflows. The calculations start from a prestellar core of dusty gas and continue until the star stops growing. The accretion ends when the remnants of the core are ejected, mostly by the force of the direct stellar radiation in the polar direction and elsewhere by the reradiated thermal infrared radiation. How long the accretion persists depends on whether the protostellar outflows are present. We set the mass outflow rate to 1% of the stellar sink particle's accretion rate. The outflows open a bipolar cavity extending to the core's outer edge, through which the thermal radiation readily escapes. The radiative flux is funneled into the polar directions while the core's collapse proceeds near the equator. The outflow thus extends the ''flashlight effect'', or anisotropic radiation field, found in previous studies from the few hundred AU scale of the circumstellar disk up to the 0.1 parsec scale of the core. The core's flashlight effect allows core gas to accrete on the disk for longer, in the same way that the disk's flashlight effect allows disk gas to accrete on the star for longer. Thus although the protostellar outflows remove material near the core's poles, causing slower stellar growth over the first few free-fall times, they also enable accretion to go on longer in our calculations. The outflows ultimately lead to stars of somewhat higher mass.

  4. Bipolar electrochemistry.

    PubMed

    Fosdick, Stephen E; Knust, Kyle N; Scida, Karen; Crooks, Richard M

    2013-09-27

    A bipolar electrode (BPE) is an electrically conductive material that promotes electrochemical reactions at its extremities (poles) even in the absence of a direct ohmic contact. More specifically, when sufficient voltage is applied to an electrolyte solution in which a BPE is immersed, the potential difference between the BPE and the solution drives oxidation and reduction reactions. Because no direct electrical connection is required to activate redox reactions, large arrays of electrodes can be controlled with just a single DC power supply or even a battery. The wireless aspect of BPEs also makes it possible to electrosynthesize and screen novel materials for a wide variety of applications. Finally, bipolar electrochemistry enables mobile electrodes, dubbed microswimmers, that are able to move freely in solution. PMID:23843205

  5. Types of Bipolar Disorder

    MedlinePlus

    ... Research Studies Peer Support Research WeSearchTogether Types of Bipolar Disorder There are several kinds of bipolar disorder. Each ... like an illness. What is the difference between bipolar disorder and ordinary mood swings? The three main things ...

  6. Bipolar-Battery Construction

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E.; Edwards, Dean B.

    1988-01-01

    Bipolar batteries fabricated in continuous quasi-automated process. Components of battery configured so processing steps run sequentially. Key components of battery, bipolar plate and bipolar separator, fabricated separately and later joined together.

  7. Starburst outflows from nearby galaxies

    NASA Technical Reports Server (NTRS)

    Waller, William H.

    1990-01-01

    Starburst outflows from NGC 5461, 1569 and M82 are discussed. The Sc I galaxy, M101, is reknowned for the kpc-size superassociations of star clusters and HII regions that dominate its spiral arms. NGC 5461 is one of the brightest of these superassociations, rivaling the Large Magellanic Cloud in H alpha luminosity. The NGC 5461 superassociation is dominated by a single unresolved HII region of outstanding luminosity (approx. 1000 Orion nebulae). Detailed examination of corresponding continuum images indicates that only the southern plume has any sort of stellar counterpart. The other plumes are clearly diffuse with no underlying hot stars. An image of NGC 1569 is discussed. Besides showing the peculiar arm noted by Zwicky (1971) and the filamentary extensions to the North and South (as noted by Hodge 1974), this image also reveals two arc-like features of diffuse ionized gas to the South. Both arcs are concentric with the bright center of the galaxy - where the super star clusters, A and B are located. The inner arc (Arc 1) appears to follow the same curve as the SW arm thus suggesting that the two features represent limb-brightened fragments of vast superbubble that was blown out by a central starburst sometime in the past. As the classic starburst galaxy, M82 displays all the luminous hallmarks of intense high-mass star formation and outflow activity. The diffuse H alpha and x ray emitting gas along the minor axis provides especially good evidence for a bipolar outflow of hot gas which is shock heating the swept-up interstellar medium (ISM) to temperatures of approx. 10(exp 4) K. An image shows the H alpha emission within the disk and along the minor axis. Another image shows the same field in the light of near-infrared. Both figures are based on charge coupled device images taken with the McGraw-Hill 1.3 m telescope (Waller 1989). The longer wavelength emission clearly shows a more extended morphology along the major axis. The morphological discrepancy is most

  8. MASSIVE STAR FORMATION, OUTFLOWS, AND ANOMALOUS H{sub 2} EMISSION IN Mol 121 (IRAS 20188+3928)

    SciTech Connect

    Wolf-Chase, Grace; Arvidsson, Kim; Smutko, Michael; Sherman, Reid

    2013-01-10

    We have discovered 12 new molecular hydrogen emission-line objects (MHOs) in the vicinity of the candidate massive young stellar object Mol 121, in addition to five that were previously known. H{sub 2} 2.12 {mu}m/H{sub 2} 2.25 {mu}m flux ratios indicate another region dominated by fluorescence from a photodissociation region, and one region that displays an anomalously low H{sub 2} 2.12 {mu}m/H{sub 2} 2.25 {mu}m flux ratio (<1) and coincides with a previously reported deeply embedded source (DES). Continuum observations at 3 mm reveal five dense cores; the brightest core is coincident with the DES. The next brightest cores are both associated with centimeter continuum emission. One of these is coincident with the IRAS source; the other lies at the centroid of a compact outflow defined by bipolar MHOs. The brighter of these bipolar MHOs exhibits [Fe II] emission and both MHOs are associated with CH{sub 3}OH maser emission observed at 95 GHz and 44 GHz. Masses and column densities of all five cores are consistent with theoretical predictions for massive star formation. Although it is impossible to associate all MHOs with driving sources in this region, it is evident that there are several outflows along different position angles, and some unambiguous associations can be made. We discuss implications of observed H{sub 2} 2.12 {mu}m/H{sub 2} 2.25 {mu}m and [Fe II] 1.64 {mu}m/H{sub 2} 2.12 {mu}m flux ratios and compare the estimated total H{sub 2} luminosity with the bolometric luminosity of the region. We conclude that the outflows are driven by massive young stellar objects embedded in cores that are likely to be in different evolutionary stages.

  9. Cirrus outflow dynamics

    NASA Technical Reports Server (NTRS)

    Lilly, Douglas K.

    1988-01-01

    In the present analyses of cirrus clouds' deep-convection outflow plumes as dynamically and thermodynamically active systems, the initial outflow is considered as an analog to wake collapse: after a neutrally-buoyant flow intrusion is flattened and stretched by its stratified environment, the initially isotropic turbulence within it is converted to other forms. Dugan et al.'s (1976) analytic and numerical calculations are used to predict the early spread of the outflow. Strong radiative heat flux curvature then leads to maintenance or regeneration of buoyant turbulence in the collapsed outflow plume. The rise of narrow plumes is sufficiently rapid that their mean temperature does not significantly differ from that of their environment.

  10. SUBMILLIMETER ARRAY OBSERVATIONS OF THE MOLECULAR OUTFLOW IN HIGH-MASS STAR-FORMING REGION G240.31+0.07

    SciTech Connect

    Qiu Keping; Zhang Qizhou; Wu Jingwen; Chen, H.-R.

    2009-05-01

    We present Submillimeter Array observations toward the 10{sup 4.7} L {sub sun} star-forming region G240.31+0.07, in the J = 2-1 transition of {sup 12}CO and {sup 13}CO and at 1.3 mm continuum, as well as the {sup 12}CO and {sup 13}CO observations from the Caltech Submillimeter Observatory to recover the extended emission filtered out by the interferometer. Maps of the {sup 12}CO and {sup 13}CO emission show a bipolar, wide-angle, quasi-parabolic molecular outflow, roughly coincident with an infrared nebula revealed by the Spitzer 3.6 and 4.5 {mu}m emission. The outflow has {approx}98 M {sub sun} molecular gas, making it one of the most massive molecular outflows known, and resulting in a very high mass-loss rate of 4.1 x 10{sup -3} M {sub sun} yr{sup -1} over a dynamical timescale of 2.4 x 10{sup 4} yr. The 1.3 mm continuum observations with a 4'' x 3'' beam reveal a flattened dusty envelope of {approx}150 M {sub sun}, which is further resolved with a 1.''2 x 1'' beam into three dense cores with a total mass of {approx}40 M {sub sun}. The central mm core, showing evidence of active star formation, approximately coincides with the geometric center of the bipolar outflow thus most likely harbors the powering source of the outflow. Overall, our observations provide the best case to date of a well defined wide-angle molecular outflow in a higher than 10{sup 4} L {sub sun} star-forming region. The outflow is morphologically and kinematically similar to low-mass protostellar outflows but has two to three orders of magnitude greater mass, momentum, and energy, and is apparently driven by an underlying wide-angle wind, hence further supports that high-mass stars up to late-O types, even in a crowded clustering environment, can form as a scaled-up version of low-mass star formation.

  11. Episodic High-velocity Outflows from V899 Mon: A Constraint On The Outflow Mechanisms

    NASA Astrophysics Data System (ADS)

    Ninan, J. P.; Ojha, D. K.; Philip, N. S.

    2016-07-01

    We report the detection of large variations in the outflow wind velocity from a young eruptive star, V899 Mon, during its ongoing high accretion outburst phase. Such large variations in the outflow velocity (from ‑722 to ‑425 km s‑1) have never been reported previously in this family of objects. Our continuous monitoring of this source shows that the multi-component, clumpy, and episodic high velocity outflows are stable in the timescale of a few days, and vary over the timescale of a few weeks to months. We detect significant decoupling in the instantaneous outflow strength to accretion rate. From the comparison of various possible outflow mechanisms in magnetospheric accretion of young stellar objects, we conclude magnetically driven polar winds to be the most consistent mechanism for the outflows seen in V899 Mon. The large scale fluctuations in outflow over the short period makes V899 Mon the most ideal source to constrain various magnetohydrodynamics simulations of magnetospheric accretion. Based on observations made with the Southern African Large Telescope (SALT).

  12. CARMA OBSERVATIONS OF PROTOSTELLAR OUTFLOWS IN NGC 1333

    SciTech Connect

    Plunkett, Adele L.; Arce, Hector G.; Corder, Stuartt A.; Mardones, Diego; Sargent, Anneila I.; Schnee, Scott L.

    2013-09-01

    We present observations of outflows in the star-forming region NGC 1333 using the Combined Array for Research in Millimeter-Wave Astronomy (CARMA). We combined the {sup 12}CO and {sup 13}CO (1-0) CARMA mosaics with data from the 14 m Five College Radio Astronomy Observatory to probe the central, most dense, and active region of this protostellar cluster at scales from 5'' to 7' (or 1000 AU to 0.5 pc at a distance of 235 pc). We map and identify {sup 12}CO outflows, and along with {sup 13}CO data we estimate their mass, momentum, and energy. Within the 7' Multiplication-Sign 7' map, the 5'' resolution allows for a detailed study of morphology and kinematics of outflows and outflow candidates, some of which were previously confused with other outflow emission in the region. In total, we identify 22 outflow lobes, as well as 9 dense circumstellar envelopes marked by continuum emission, of which 6 drive outflows. We calculate a total outflow mass, momentum, and energy within the mapped region of 6 M{sub Sun }, 19 M{sub Sun} km s{sup -1}, and 7 Multiplication-Sign 10{sup 44} erg, respectively. Within this same region, we compare outflow kinematics with turbulence and gravitational energy, and we suggest that outflows are likely important agents for the maintenance of turbulence in this region. In the earliest stages of star formation, outflows do not yet contribute enough energy to totally disrupt the clustered region where most star formation is happening, but have the potential to do so as the protostellar sources evolve. Our results can be used to constrain outflow properties, such as outflow strength, in numerical simulations of outflow-driven turbulence in clusters.

  13. Mid-infrared imaging of the bipolar planetary nebula M2-9 from SOFIA

    SciTech Connect

    Werner, M. W.; Sahai, R.; Davis, J.; Livingston, J.; Lykou, F.; DE Buizer, J.; Keller, L.; Adams, J.; Gull, G.; Henderson, C.; Herter, T.; Schoenwald, J.

    2014-01-10

    We have imaged the bipolar planetary nebula M2-9 using SOFIA's FORCAST instrument in six wavelength bands between 6.6 and 37.1 μm. A bright central point source, unresolved with SOFIA's ∼4''-5'' beam, is seen at each wavelength, and the extended bipolar lobes are clearly seen at 19.7 μm and beyond. The photometry between 10 and 25 μm is well fit by the emission predicted from a stratified disk seen at large inclination, as has been proposed for this source by Lykou et al. and by Smith and Gehrz. The principal new results in this paper relate to the distribution and properties of the dust that emits the infrared radiation. In particular, a considerable fraction of this material is spread uniformly through the lobes, although the dust density does increase at the sharp outer edge seen in higher resolution optical images of M2-9. The dust grain population in the lobes shows that small (<0.1 μm) and large (>1 μm) particles appear to be present in roughly equal amounts by mass. We suggest that collisional processing within the bipolar outflow plays an important role in establishing the particle size distribution.

  14. Outflow Propagation in Collapsars: Collimated Jets And Expanding Outflows

    SciTech Connect

    Mizuta, A.; Yamasaki, T.; Nagataki, S.; Mineshige, S.; /Kyoto U., Yukawa Inst., Kyoto /KIPAC, Menlo Park

    2007-06-08

    We investigate the outflow propagation in the collapsar in the context of gamma-ray bursts (GRBs) with 2D relativistic hydrodynamic simulations. We vary the specific internal energy and bulk Lorentz factor of the injected outflow from non-relativistic regime to relativistic one, fixing the power of the outflow to be 10{sup 51}erg s{sup -1}. We observed the collimated outflow, when the Lorentz factor of the injected outflow is roughly greater than 2. To the contrary, when the velocity of the injected outflow is slower, the expanding outflow is observed. The transition from collimated jet to expanding outflow continuously occurs by decreasing the injected velocity. Different features of the dynamics of the outflows would cause the difference between the GRBs and similar phenomena, such as, X-ray flashes.

  15. AN ENVELOPE DISRUPTED BY A QUADRUPOLAR OUTFLOW IN THE PRE-PLANETARY NEBULA IRAS 19475+3119

    SciTech Connect

    Hsu, Ming-Chien; Lee, Chin-Fei E-mail: cflee@asiaa.sinica.edu.tw

    2011-07-20

    IRAS 19475+3119 is a quadrupolar pre-planetary nebula (PPN), with two bipolar lobes, one in the east-west (E-W) direction and one in the southeast-northwest (SE-NW) direction. We have observed it in CO J = 2-1 with the Submillimeter Array at {approx}1'' resolution. The E-W bipolar lobe is known to trace a bipolar outflow and it is detected at high velocity. The SE-NW bipolar lobe appears at low velocity, and could trace a bipolar outflow moving in the plane of the sky. Two compact clumps are seen at low velocity around the common waist of the two bipolar lobes, spatially coincident with the two emission peaks in the NIR, tracing dense envelope material. They are found to trace the two limb-brightened edges of a slowly expanding torus-like circumstellar envelope produced in the late asymptotic giant branch phase. This torus-like envelope originally could be either a torus or a spherical shell, and it appears as it is now because of the two pairs of cavities along the two bipolar lobes. Thus, the envelope appears to be disrupted by the two bipolar outflows in the PPN phase.

  16. Treatment of source-separated urine by a combination of bipolar electrodialysis and a gas transfer membrane.

    PubMed

    Pronk, W; Biebow, M; Boller, M

    2006-01-01

    Urine contains nutrients which can be applied usefully as a fertiliser in agriculture, but the relatively high pH can lead to ammonia evaporation. Electrodialysis with bipolar membranes was combined with an additional mass transfer unit in order to render a product containing ammonium and phosphate at a low pH. In one case, the additional mass transfer unit consisted of bubble columns placed in acid and basic concentrate streams, connected with a circulating gas phase. In the other case, the unit consisted of a gas-filled (hydrophobic) membrane placed in between the circulating acid and basic concentrate streams. The results showed that ammonia was transferred through the gas phase, but also carbonate, which is present in stored urine originating from the hydrolysis of urea. Although the pH in the product stream decreases initially, it rises above pH 7 at longer operation times. This pH increase can be attributed to a combination of proton compensating effects. The use of ammonia-selective membranes for the transfer into the acid concentrate could provide a solution to generate an ammonium phosphate product at low pH and high recoveries. PMID:16605026

  17. Galaxy Outflows Without Supernovae

    NASA Astrophysics Data System (ADS)

    Sur, Sharanya; Scannapieco, Evan; Ostriker, Eve C.

    2016-02-01

    High surface density, rapidly star-forming galaxies are observed to have ≈50-100 km s-1 line of sight velocity dispersions, which are much higher than expected from supernova driving alone, but may arise from large-scale gravitational instabilities. Using three-dimensional simulations of local regions of the interstellar medium, we explore the impact of high velocity dispersions that arise from these disk instabilities. Parametrizing disks by their surface densities and epicyclic frequencies, we conduct a series of simulations that probe a broad range of conditions. Turbulence is driven purely horizontally and on large scales, neglecting any energy input from supernovae. We find that such motions lead to strong global outflows in the highly compact disks that were common at high redshifts, but weak or negligible mass loss in the more diffuse disks that are prevalent today. Substantial outflows are generated if the one-dimensional horizontal velocity dispersion exceeds ≈35 km s-1, as occurs in the dense disks that have star-formation rate (SFR) densities above ≈0.1 M⊙ yr-1 kpc-2. These outflows are triggered by a thermal runaway, arising from the inefficient cooling of hot material coupled with successive heating from turbulent driving. Thus, even in the absence of stellar feedback, a critical value of the SFR density for outflow generation can arise due to a turbulent heating instability. This suggests that in strongly self-gravitating disks, outflows may be enhanced by, but need not caused by, energy input from supernovae.

  18. Triggered star formation: Rotation, magnetic fields and outflows

    NASA Astrophysics Data System (ADS)

    Frank, A.; Li, S.; Blackman, E. G.

    2015-12-01

    Star formation can be triggered by compression from wind or supernova driven shock waves that sweep over molecular clouds. In a previous work we used Adaptive Mesh Refinement (AMR) simulation methods, including sink particles, to simulate the full collapse of a stable Bonnor-Ebert sphere subjected to a passing shock. We tracked the flow of cloud material after a star (a sink particle) had formed. For rotating clouds we observed the formation of disks which then interact with the post-shock flow. In this paper we take the next step forward in complexity, presenting first results of simulations that include a magnetized cloud. Our results show that after a disk is formed a collimated magneto-centrifugal outflow is launched. The outflow is bipolar but asymmetric, due to interactions with the shocked flow. We explore the influence of the outflows on the post-triggering collapse dynamics.

  19. Spitzer IRAC Detection of Protostellar Outflows

    NASA Astrophysics Data System (ADS)

    Ybarra, Jason E.; Lada, E. A.; Balog, Z.

    2009-01-01

    We will discuss a method for detecting shocked H2 emission in IRAC band images and distinguishing H2 knots from stellar sources. Using this method we will present Spitzer IRAC imaging of a recently discovered parsec scale protostellar outflow. This outflow was detected in all four IRAC bands. The proposed source of the outflow is an embedded Class 0 object detected in the MIPS images. This work is based in part on archival data obtained with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by an award issued by JPL/Caltech and also a NASA LTSA Grant NNG05GD66G

  20. Studies of Quasar Outflows

    NASA Technical Reports Server (NTRS)

    Arav, Nahum

    2002-01-01

    The main aim of this research program is to determine the ionization equilibrium and abundances in quasar outflows. Especially in the broad absorption line QSO PG 0946+301. We find that the outflow's metalicity is consistent with being solar, while the abundance ratio of phosphorus to other metals is at least ten times solar. These findings are based on diagnostics that are not sensitive to saturation and partial covering effects in the BALs (Broad Adsorption Lines), which considerably weakened previous claims for enhanced metalicity. Ample evidence for these effects is seen in the spectrum.

  1. Kiloparsec-scale outflows are prevalent among luminous AGN: outflows and feedback in the context of the overall AGN population

    NASA Astrophysics Data System (ADS)

    Harrison, C. M.; Alexander, D. M.; Mullaney, J. R.; Swinbank, A. M.

    2014-07-01

    We present integral field unit observations covering the [O III]λλ4959, 5007 and Hβ emission lines of 16 z < 0.2 type 2 active galactic nuclei (AGN). Our targets are selected from a well-constrained parent sample of ≈24 000 AGN so that we can place our observations into the context of the overall AGN population. Our targets are radio quiet with star formation rates (SFRs; ≲[10-100] M⊙ yr-1) that are consistent with normal star-forming galaxies. We decouple the kinematics of galaxy dynamics and mergers from outflows. We find high-velocity ionized gas (velocity widths ≈600-1500 km s-1; maximum velocities ≤1700 km s-1) with observed spatial extents of ≳(6-16) kpc in all targets and observe signatures of spherical outflows and bi-polar superbubbles. We show that our targets are representative of z < 0.2, luminous (i.e. L[O III] > 1041.7 erg s-1) type 2 AGN and that ionized outflows are not only common but also in ≥70 per cent (3σ confidence) of cases, they are extended over kiloparsec scales. Our study demonstrates that galaxy-wide energetic outflows are not confined to the most extreme star-forming galaxies or radio-luminous AGN; however, there may be a higher incidence of the most extreme outflow velocities in quasars hosted in ultraluminous infrared galaxies. Both star formation and AGN activity appear to be energetically viable to drive the outflows and we find no definitive evidence that favours one process over the other. Although highly uncertain, we derive mass outflow rates (typically ≈10 times the SFRs), kinetic energies (≈0.5-10 per cent of LAGN) and momentum rates (typically ≳10-20 × LAGN/c) consistent with theoretical models that predict AGN-driven outflows play a significant role in shaping the evolution of galaxies.

  2. Metallicity and Quasar Outflows

    NASA Astrophysics Data System (ADS)

    Wang, Huiyuan; Zhou, Hongyan; Yuan, Weimin; Wang, Tinggui

    2012-06-01

    Correlations of the outflow strength of quasars, as measured by the blueshift and asymmetry index (BAI) of the C IV line, with intensities and ratios of broad emission lines, based on composite quasar spectra built from the Sloan Digital Sky Survey, are investigated. We find that most of the line ratios of other ions to C IV increase prominently with BAI. These behaviors can be well understood in the context of increasing metallicity with BAI. The strength of the dominant coolant, C IV line, decreases, and weak collisionally excited lines increase with gas metallicity as a result of the competition between different line coolants. Using Si IV+O IV]/C IV as an indicator of gas metallicity, we present, for the first time, a strong correlation between the metallicity and the outflow strength of quasars over a wide range of 1.7-6.9 times solar abundance. Our result implies that metallicity plays an important role in the formation of quasar outflows, likely by affecting outflow acceleration. This effect may have a profound impact on galaxy evolution via momentum feedback and chemical enrichment.

  3. METALLICITY AND QUASAR OUTFLOWS

    SciTech Connect

    Wang, Huiyuan; Zhou, Hongyan; Wang, Tinggui; Yuan, Weimin

    2012-06-01

    Correlations of the outflow strength of quasars, as measured by the blueshift and asymmetry index (BAI) of the C IV line, with intensities and ratios of broad emission lines, based on composite quasar spectra built from the Sloan Digital Sky Survey, are investigated. We find that most of the line ratios of other ions to C IV increase prominently with BAI. These behaviors can be well understood in the context of increasing metallicity with BAI. The strength of the dominant coolant, C IV line, decreases, and weak collisionally excited lines increase with gas metallicity as a result of the competition between different line coolants. Using Si IV+O IV]/C IV as an indicator of gas metallicity, we present, for the first time, a strong correlation between the metallicity and the outflow strength of quasars over a wide range of 1.7-6.9 times solar abundance. Our result implies that metallicity plays an important role in the formation of quasar outflows, likely by affecting outflow acceleration. This effect may have a profound impact on galaxy evolution via momentum feedback and chemical enrichment.

  4. Bipolar lead acid battery development

    NASA Technical Reports Server (NTRS)

    Eskra, Michael; Vidas, Robin; Miles, Ronald; Halpert, Gerald; Attia, Alan; Perrone, David

    1991-01-01

    A modular bipolar battery configuration is under development at Johnson Control, Inc. (JCI) and the Jet Propulsion Laboratory (JPL). The battery design, incorporating proven lead acid electrochemistry, yields a rechargeable, high-power source that is light weight and compact. This configuration offers advantages in power capability, weight, and volume over conventional monopolar batteries and other battery chemistries. The lead acid bipolar battery operates in a sealed, maintenance-free mode allowing for maximum application flexibility. It is ideal for high-voltage and high-power applications.

  5. Bipolar lead acid battery development

    NASA Astrophysics Data System (ADS)

    Eskra, Michael; Vidas, Robin; Miles, Ronald; Halpert, Gerald; Attia, Alan; Perrone, David

    A modular bipolar battery configuration is under development at Johnson Control, Inc. (JCI) and the Jet Propulsion Laboratory (JPL). The battery design, incorporating proven lead acid electrochemistry, yields a rechargeable, high-power source that is light weight and compact. This configuration offers advantages in power capability, weight, and volume over conventional monopolar batteries and other battery chemistries. The lead acid bipolar battery operates in a sealed, maintenance-free mode allowing for maximum application flexibility. It is ideal for high-voltage and high-power applications.

  6. Episodic outflows from high-mass protostars

    SciTech Connect

    Mitchell, G.F.; Maillard, J.P.; Hasegawa, T.I. Canada-France-Hawaii Telescope Corp., Waimea, HI CNRS, Institut d'Astrophysique, Paris Duke University, Durham, NC )

    1991-04-01

    This paper examines the kinematics and physical properties of the outflowing gas from seven luminous deeply embedded young stellar objects or protostars: M8E-IR, GL 490, GL 2591, W3 IRS 5, NGC 7538 IRS 1, NGC 7538 IRS 9, and S140 IRS 1. The outflows are seen as blueshifted absorption features in lines of the fundamental band of CO. The CO lines seen in absorption are compared with CO lines seen in emission at mm wavelengths. New CO J = 2-1 emission-line data are presented for the first five of the sources. 60 refs.

  7. Suppression of galactic outflows by cosmological infall and circumgalactic medium

    NASA Astrophysics Data System (ADS)

    Singh, Priyanka; Rana, Sandeep; Bagla, Jasjeet S.; Nath, Biman B.

    2016-06-01

    We investigate the relative importance of two galactic outflow suppression mechanisms: (a) cosmological infall of the intergalactic gas on to the galaxy, and (b) the existence of a hot circumgalactic medium (CGM). Considering only radial motion, the infall reduces the speed of outflowing gas and even halts the outflow, depending on the mass and redshift of the galaxy. For star-forming galaxies, there exists an upper mass limit beyond which outflows are suppressed by the gravitational field of the galaxy. We find that infall can reduce this upper mass limit approximately by a factor of 2 (independent of the redshift). Massive galaxies (≳1012 M⊙) host large reservoir of hot, diffuse CGM around the central part of the galaxy. The CGM acts as a barrier between the infalling and outflowing gas and provides an additional source of outflow suppression. We find that at low redshifts (z ≲ 3.5), the CGM is more effective than the infall in suppressing the outflows. Together, these two processes give a mass range in which galaxies are unable to have effective outflows. We also discuss the impact of outflow suppression on the enrichment history of the galaxy and its environment.

  8. Discovery of Relativistic Outflow in the Seyfert Galaxy Ark 564

    NASA Astrophysics Data System (ADS)

    Gupta, A.; Mathur, S.; Krongold, Y.; Nicastro, F.

    2013-07-01

    We present Chandra High Energy Transmission Grating Spectra of the narrow-line Seyfert-1 galaxy Ark 564. The spectrum shows numerous absorption lines which are well modeled with low-velocity outflow components usually observed in Seyfert galaxies. There are, however, some residual absorption lines which are not accounted for by low-velocity outflows. Here, we present identifications of the strongest lines as Kα transitions of O VII (two lines) and O VI at outflow velocities of ~0.1c. These lines are detected at 6.9σ, 6.2σ, and 4.7σ, respectively, and cannot be due to chance statistical fluctuations. Photoionization models with ultra-high velocity components improve the spectral fit significantly, providing further support for the presence of relativistic outflow in this source. Without knowing the location of the absorber, its mass and energy outflow rates cannot be well constrained; we find \\dot{E}(outflow)/L_{bol} lower limit of >=0.006% assuming a bi-conical wind geometry. This is the first time that absorption lines with ultra-high velocities are unambiguously detected in the soft X-ray band. The presence of outflows with relativistic velocities in active galactic nuclei (AGNs) with Seyfert-type luminosities is hard to understand and provides valuable constraints to models of AGN outflows. Radiation pressure is unlikely to be the driving mechanism for such outflows and magnetohydrodynamic may be involved.

  9. Shaping Outflows from Evolved Stars: Secrets Revealed by Chandra

    NASA Astrophysics Data System (ADS)

    Kastner, Joel H.

    2011-05-01

    Planetary nebulae (PNe), the near-endpoints of stellar evolution for intermediate-mass stars, exhibit a dizzying variety of optical/near-infrared morphologies: round; elliptical; bipolar; highly point-symmetric; chaotic and clumpy. The physical mechanisms responsible for this morphological menagerie are hotly debated. It is thought that the shape of a PN results from the sculpting of previously ejected, slow-moving (red giant) stellar envelope material by a fast wind from a (newly unveiled) white dwarf at the PN's core. But to explain the large fraction of nonspherical PNe -- which are presumably shaped by aspherical fast winds -- some models now further propose that many (perhaps most) PNe are the products of interacting binary systems. Chandra is yielding valuable insight into these stellar outflow shaping processes. Chandra imaging spectroscopy of PNe provides a unique means to determine the X-ray surface brightness distributions, temperatures, emission measures, and elemental abundances within the "hot bubbles" generated by fast wind shocks. Chandra observations of PNe have also revealed intriguing examples of unresolved X-ray sources that are too hard to be modeled as photospheric emission from hot white dwarfs. Such hard X-ray point sources are likely indicative of the presence of binary companions and/or accretion processes at PN central stars. I summarize the progress in these areas resulting from Chandra's first dozen years, and present early results from the first systematic Chandra survey of PNe in the solar neighborhood -- a survey designed to understand the formation and evolution of hot bubbles, and to establish the frequency and characteristics of point-like X-ray sources, within PNe with names like the Ring, the Dumbbell, the Owl, and Saturn. This work is supported by NASA Astrophysics Data Analysis Program and Chandra X-ray Center (CXC) grants to RIT. The CXC is operated by SAO for and on behalf of NASA under contract NAS8-03060.

  10. Electrical resistivity change in Al:ZnO thin films dynamically deposited by bipolar pulsed direct-current sputtering and a remote plasma source

    SciTech Connect

    Yang, Wonkyun; Joo, Junghoon

    2010-07-15

    The Al-doped ZnO (AZO) thin films for a transparent conducting oxide in solar cell devices were deposited by bipolar pulsed dc magnetron sputtering. This work was performed in an in-line type system and investigated AZO films in a static deposition mode and dynamic one, which is more important in the practical fields. Because of this dynamic deposition process, the zigzagged columnar structure was observed. This resulted in the decreasing electrical property, optical properties, and surface roughness. As a deposition in the dynamic mode, the resistivity increased from 1.64x10{sup -3} to 2.50x10{sup -3} {Omega} cm, as compared to that in the static mode, and the transmittance also decreased from 83.9% to 78.3%. To recover the disadvantage, a remote plasma source (RPS) was supported between the substrate and target for reducing zigzagged formation during the deposition. The deposition rate decreased by using RPS, but the electrical and optical properties of films got better than only dynamic mode. The resistivity and transmittance in the dynamic mode using RPS were 2.1x10{sup -3} {Omega} cm and 85.5%, respectively. In this study, the authors found the possibility to advance the electrical and optical properties of AZO thin films in the industry mode.

  11. Bipolar offspring: a window into bipolar disorder evolution.

    PubMed

    Chang, Kiki; Steiner, Hans; Dienes, Kimberly; Adleman, Nancy; Ketter, Terence

    2003-06-01

    Children of parents with bipolar disorder (bipolar offspring) represent a rich cohort for study with potential for illumination of prodromal forms of bipolar disorder. Due to their high-risk nature, bipolar offspring may present phenomenological, temperamental, and biological clues to early presentations of bipolar disorder. This article reviews the evidence for establishing bipolar offspring as a high-risk cohort, the studies which point to possible prodromal states in bipolar offspring, biological findings in bipolar offspring which may be indicators of even higher risk for bipolar disorder, initial attempts at early intervention in prodromal pediatric bipolar disorder, and implications for future research. PMID:12788239

  12. Help With Bipolar Disorders

    MedlinePlus

    ... a Psychiatrist Patients & Families All Topics Help With Bipolar Disorders Curated and updated for the community by APA Topic Information Bipolar disorders are brain disorders that cause changes in a ...

  13. The nature of AFGL 2591 and its associated molecular outflow: Infrared and millimeter-wave observations

    NASA Technical Reports Server (NTRS)

    Lada, C. J.; Thronson, H. A., Jr.; Smith, H. A.; Schwartz, P. R.; Glaccum, W.

    1984-01-01

    The results of infrared photometry from 2 to 160 microns of AFGL and CO(12) observations of its associated molecular cloud and high velocity molecular outflow are presented and discussed. The observed solar luminosity is 6.7 x 10(4) at a distance of 2 kpc. The spectrum of AFGL 2591 is interpreted in the context of a model in which a single embedded object is the dominant source of the infrared luminosity. This object is determined to be surrounded by a compact, optically thick dust shell with a temperature in excess of several hundred degrees kelvin. The extinction to this source is estimated to be between 26 and 50 visual magnitudes. The absolute position of the infrared sources at 10 microns was determined to an accuracy of + or in. This indicates for the first time that the IR source and H2O source are not coincident. The CO(12) observations show the high-velocity molecular flow near AFGL 2591 to be extended, bipolar and roughly centered on the infrared emission. The observations suggest that the red-shifted flow component extends beyond the boundary of the ambient cloud within which AFGL 2591 is embedded. The CO(12) observations also show that AFGL 2591 is embedded in a molecular cloud with an LSR velocity of -5 km/s.

  14. Models of polarized infrared emission from bipolar nebulae

    NASA Technical Reports Server (NTRS)

    Burns, M. S.; Johnson, P.; Thronson, H. A., Jr.

    1986-01-01

    Many stars with circumstellar dust shells show a high degree of linear polarization (Sato et al. 1985). We are developing a model which assumes that the polarization arises from scattering by circumstellar dust. Our model assumes a geometry in which the star is surrounded by an optically thin spherical dust shell and embedded within an optically thick disk. This geometry is consistent with that proposed for objects with bipolar molecular outflow. This is important because many bipolar flow objects have also been observed to be highly polarized. The high degree of linear polarization is produced because the disk differentially attenuates the light from the star. The light incident from the point source is attenuated by a factor of exp(-tau/cos theta) where theta is the angle between a ray from the point source to the scatterer and a ray normal to the disk; tau is the optical depth at the wavelength of interest. Hence, the light scattered from the regions directly above and below the disk give the largest contribution to the total flux. The scattering angle for light from these regions is near 90 deg., so the light is strongly polarized and, in the Rayleigh scattering regime, is polarized parallel to the disk. The Stokes parameters for the scattered light from each particle in the shell are calculated by using the scattering matrix elements generated by a Mie scattering program. After the Stokes parameters for each particle are computed they are summed to give the Stokes parameters for the entire shell. Two graphs are presented which show the intensity and polarization spectrum generated by our model using the optical constants for astronomical silicates as defined by Draine and Lee (1984).

  15. Bipolar pulse forming line

    DOEpatents

    Rhodes, Mark A.

    2008-10-21

    A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  16. Nutrition and Bipolar Depression.

    PubMed

    Beyer, John L; Payne, Martha E

    2016-03-01

    As with physical conditions, bipolar disorder is likely to be impacted by diet and nutrition. Patients with bipolar disorder have been noted to have relatively unhealthy diets, which may in part be the reason they also have an elevated risk of metabolic syndrome and obesity. An improvement in the quality of the diet should improve a bipolar patient's overall health risk profile, but it may also improve their psychiatric outcomes. New insights into biological dysfunctions that may be present in bipolar disorder have presented new theoretic frameworks for understanding the relationship between diet and bipolar disorder. PMID:26876319

  17. Confronting the outflow-regulated cluster formation model with observations

    SciTech Connect

    Nakamura, Fumitaka; Li, Zhi-Yun E-mail: zl4h@virginia.edu

    2014-03-10

    Protostellar outflows have been shown theoretically to be capable of maintaining supersonic turbulence in cluster-forming clumps and keeping the star formation rate per free-fall time as low as a few percent. We aim to test two basic predictions of this outflow-regulated cluster formation model, namely, (1) the clump should be close to virial equilibrium and (2) the turbulence dissipation rate should be balanced by the outflow momentum injection rate, using recent outflow surveys toward eight nearby cluster-forming clumps (B59, L1551, L1641N, Serpens Main Cloud, Serpens South, ρ Oph, IC 348, and NGC 1333). We find, for almost all sources, that the clumps are close to virial equilibrium and the outflow momentum injection rate exceeds the turbulence momentum dissipation rate. In addition, the outflow kinetic energy is significantly smaller than the clump gravitational energy for intermediate and massive clumps with M {sub cl} ≳ a few × 10{sup 2} M {sub ☉}, suggesting that the outflow feedback is not enough to disperse the clump as a whole. The number of observed protostars also indicates that the star formation rate per free-fall time is as small as a few percent for all clumps. These observationally based results strengthen the case for outflow-regulated cluster formation.

  18. THE MULTIPHASE STRUCTURE AND POWER SOURCES OF GALACTIC WINDS IN MAJOR MERGERS

    SciTech Connect

    Rupke, David S. N.; Veilleux, Sylvain

    2013-05-01

    Massive, galaxy-scale outflows are known to be ubiquitous in major mergers of disk galaxies in the local universe. In this paper, we explore the multiphase structure and power sources of galactic winds in six ultraluminous infrared galaxies (ULIRGs) at z < 0.06 using deep integral field spectroscopy with the Gemini Multi-Object Spectrograph (GMOS) on Gemini North. We probe the neutral, ionized, and dusty gas phases using Na I D, strong emission lines ([O I], H{alpha}, and [N II]), and continuum colors, respectively. We separate outflow motions from those due to rotation and tidal perturbations, and find that all of the galaxies in our sample host high-velocity flows on kiloparsec scales. The properties of these outflows are consistent with multiphase (ionized, neutral, and dusty) collimated bipolar winds emerging along the minor axis of the nuclear disk to scales of 1-2 kpc. In two cases, these collimated winds take the form of bipolar superbubbles, identified by clear kinematic signatures. Less collimated (but still high-velocity) flows are also present on scales up to 5 kpc in most systems. The three galaxies in our sample with obscured QSOs host higher velocity outflows than those in the three galaxies with no evidence for an active galactic nucleus. The peak outflow velocity in each of the QSOs is in the range 1450-3350 km s{sup -1}, and the highest velocities (2000-3000 km s{sup -1}) are seen only in ionized gas. The outflow energy and momentum in the QSOs are difficult to produce from a starburst alone, but are consistent with the QSO contributing significantly to the driving of the flow. Finally, when all gas phases are accounted for, the outflows are massive enough to provide negative feedback to star formation.

  19. The Resolved Outflow from 3C 48

    NASA Astrophysics Data System (ADS)

    Shih, Hsin-Yi; Stockton, Alan

    2014-10-01

    We investigate the properties of the high-velocity outflow driven by the young radio jet of 3C 48, a compact-steep-spectrum source. We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telecope to obtain (1) low-resolution UV and optical spectra and (2) multi-slit medium-resolution spectra of the ionized outflow. With supporting data from ground-based spectrographs, we are able to accurately measure the ratios of diagnostic emission lines such as [O III] λ5007, [O III] λ3727, [N II] λ6548, Hα, Hβ, [Ne V] λ3425, and [Ne III] λ3869. We fit the observed emission-line ratios using a range of ionization models, powered by active galactic nucleus (AGN) radiation and shocks, produced by the MAPPINGS code. We have determined that AGN radiation is likely the dominant ionization source. The outflow's density is estimated to be in the range n = 103-104 cm-3, the mass is ~6 × 106 M ⊙, and the metallicity is likely equal to or higher than solar. Compared with the typical outflows associated with more evolved radio jets, this young outflow is denser, less massive, and more metal rich. Multi-slit observations allow us to construct a two-dimensional velocity map of the outflow that shows a wide range of velocities with distinct velocity components, suggesting a wide-angle clumpy outflow. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO-11574. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Some of the

  20. Protostellar Outflow Evolution in Turbulent Environments

    SciTech Connect

    Cunningham, A; Frank, A; Carroll, J; Blackman, E; Quillen, A

    2008-04-11

    The link between turbulence in star formatting environments and protostellar jets remains controversial. To explore issues of turbulence and fossil cavities driven by young stellar outflows we present a series of numerical simulations tracking the evolution of transient protostellar jets driven into a turbulent medium. Our simulations show both the effect of turbulence on outflow structures and, conversely, the effect of outflows on the ambient turbulence. We demonstrate how turbulence will lead to strong modifications in jet morphology. More importantly, we demonstrate that individual transient outflows have the capacity to re-energize decaying turbulence. Our simulations support a scenario in which the directed energy/momentum associated with cavities is randomized as the cavities are disrupted by dynamical instabilities seeded by the ambient turbulence. Consideration of the energy power spectra of the simulations reveals that the disruption of the cavities powers an energy cascade consistent with Burgers-type turbulence and produces a driving scale-length associated with the cavity propagation length. We conclude that fossil cavities interacting either with a turbulent medium or with other cavities have the capacity to sustain or create turbulent flows in star forming environments. In the last section we contrast our work and its conclusions with previous studies which claim that jets can not be the source of turbulence.

  1. Protostellar Outflow Evolution in Turbulent Environments

    NASA Astrophysics Data System (ADS)

    Cunningham, Andrew J.; Frank, Adam; Carroll, Jonathan; Blackman, Eric G.; Quillen, Alice C.

    2009-02-01

    The link between turbulence in star-forming environments and protostellar jets remains controversial. To explore issues of turbulence and fossil cavities driven by young stellar outflows, we present a series of numerical simulations tracking the evolution of transient protostellar jets driven into a turbulent medium. Our simulations show both the effect of turbulence on outflow structures and, conversely, the effect of outflows on the ambient turbulence. We demonstrate how turbulence will lead to strong modifications in jet morphology. More importantly, we demonstrate that individual transient outflows have the capacity to re-energize decaying turbulence. Our simulations support a scenario in which the directed energy/momentum associated with cavities is randomized as the cavities are disrupted by dynamical instabilities seeded by the ambient turbulence. Consideration of the energy power spectra of the simulations reveals that the disruption of the cavities powers an energy cascade consistent with Burgers'-type turbulence and produces a driving scale length associated with the cavity propagation length. We conclude that fossil cavities interacting either with a turbulent medium or with other cavities have the capacity to sustain or create turbulent flows in star-forming environments. In the last section, we contrast our work and its conclusions with previous studies which claim that jets cannot be the source of turbulence.

  2. Estimation of the mass outflow rates around rotating black holes

    NASA Astrophysics Data System (ADS)

    Aktar, Ramiz; Das, Santabrata

    We consider steady, advective, rotating, inviscid accretion disc around the spinning black holes to compute the mass outflow rate (R_{dot{m}}) defined as the ratio of mass flux of outflowing to the inflowing matter. Due to centrifugal barrier, accreting matter suffers discontinuous shock transition and because of shock compression, the post-shock matter becomes hot and denser than the pre-shock matter. We call the post-shock disc as Post Shock Corona (PSC). During accretion, a part of the inflowing matter deflects as bipolar outflows due to the presence of excess thermal gradient force at PSC. We find that R_{dot{m}}is directly correlated with the spin of the black hole (a_{k}) for the same set of inflow parameter, namely specific energy (E) and specific angular momentum (λ). We observe that the maximum outflow rate(R_{dot{m}}^{max}) weakly depends on spin (a_{k}) that lies in the range˜ 17% - 18% of the inflow rate.

  3. Gas physical conditions and kinematics of the giant outflow Ou4

    NASA Astrophysics Data System (ADS)

    Corradi, Romano L. M.; Grosso, Nicolas; Acker, Agnès; Greimel, Robert; Guillout, Patrick

    2014-10-01

    Context. The recently discovered bipolar outflow Ou4 has a projected size of more than one degree in the plane of the sky. It is apparently centred on the young stellar cluster - whose most massive representative is the triple system HR 8119 - inside the H ii region Sh 2-129. The driving source, the nature, and the distance of Ou4 are not known. Aims: The basic properties of Ou4 and its environment are investigated to shed light on the origin of this remarkable outflow. Methods: Deep narrow-band imagery of the whole nebula at arcsecond resolution was obtained to study the details of its morphology. Long-slit spectroscopy of the bipolar lobe tips was secured to determine the gas ionisation mechanism, physical conditions, and line-of-sight velocities. An estimate of the proper motions at the tip of the south lobe using archival plate images was attempted. The existing multi-wavelength data for Sh 2-129 and HR 8119 were also comprehensively reviewed. Results: The observed morphology of Ou4, its emission-line spatial distribution, line flux ratios, and the kinematic modelling developed adopting a bow-shock parabolic geometry, illustrate the expansion of a shock-excited fast collimated outflow. The observed radial velocities of Ou4 and its reddening are consistent with those of Sh 2-129 and HR 8119. The improved determination of the distance to HR 8119 (composed of two B0 V and one B0.5 V stars) and Sh 2-129 is 712 pc. We identify in WISE images at 22 μm an emission bubble of 5' radius (1 pc at the distance above) emitted by hot (107 K) dust grains, located inside the central part of Ou4 and corresponding to several [O iii] emission features of Ou4. Conclusions: The apparent position of Ou4 and the properties studied in this work are consistent with the hypothesis that Ou4 is located inside the Sh 2-129 H ii region, suggesting that it was launched some 90 000 yr ago by HR 8119. The outflow total kinetic energy is estimated to be ≈4 × 1047 ergs. However, we cannot

  4. HOT ELECTROMAGNETIC OUTFLOWS. I. ACCELERATION AND SPECTRA

    SciTech Connect

    Russo, Matthew; Thompson, Christopher

    2013-04-20

    The theory of cold, relativistic, magnetohydrodynamic outflows is generalized by the inclusion of an intense radiation source. In some contexts, such as the breakout of a gamma-ray burst (GRB) jet from a star, the outflow is heated to a high temperature at a large optical depth. Eventually it becomes transparent and is pushed to a higher Lorentz factor by a combination of the Lorentz force and radiation pressure. We obtain its profile, both inside and outside the fast magnetosonic critical point, when the poloidal magnetic field is radial and monopolar. Most of the energy flux is carried by the radiation field and the toroidal magnetic field that is wound up close to the rapidly rotating engine. Although the entrained matter carries little energy, it couples the radiation field to the magnetic field. Then the fast critical point is pulled inward from infinity and, above a critical radiation intensity, the outflow is accelerated mainly by radiation pressure. We identify a distinct observational signature of this hybrid outflow: a hardening of the radiation spectrum above the peak of the seed photon distribution, driven by bulk Compton scattering. The non-thermal spectrum-obtained by a Monte Carlo method-is most extended when the Lorentz force dominates the acceleration, and the seed photon beam is wider than the Lorentz cone of the MHD fluid. This effect is a generic feature of hot, magnetized outflows interacting with slower relativistic material. It may explain why some GRB spectra appear to peak at photon energies above the original Amati et al. scaling. A companion paper addresses the case of jet breakout, where diverging magnetic flux surfaces yield strong MHD acceleration over a wider range of Lorentz factor.

  5. Hot Electromagnetic Outflows. I. Acceleration and Spectra

    NASA Astrophysics Data System (ADS)

    Russo, Matthew; Thompson, Christopher

    2013-04-01

    The theory of cold, relativistic, magnetohydrodynamic outflows is generalized by the inclusion of an intense radiation source. In some contexts, such as the breakout of a gamma-ray burst (GRB) jet from a star, the outflow is heated to a high temperature at a large optical depth. Eventually it becomes transparent and is pushed to a higher Lorentz factor by a combination of the Lorentz force and radiation pressure. We obtain its profile, both inside and outside the fast magnetosonic critical point, when the poloidal magnetic field is radial and monopolar. Most of the energy flux is carried by the radiation field and the toroidal magnetic field that is wound up close to the rapidly rotating engine. Although the entrained matter carries little energy, it couples the radiation field to the magnetic field. Then the fast critical point is pulled inward from infinity and, above a critical radiation intensity, the outflow is accelerated mainly by radiation pressure. We identify a distinct observational signature of this hybrid outflow: a hardening of the radiation spectrum above the peak of the seed photon distribution, driven by bulk Compton scattering. The non-thermal spectrum—obtained by a Monte Carlo method—is most extended when the Lorentz force dominates the acceleration, and the seed photon beam is wider than the Lorentz cone of the MHD fluid. This effect is a generic feature of hot, magnetized outflows interacting with slower relativistic material. It may explain why some GRB spectra appear to peak at photon energies above the original Amati et al. scaling. A companion paper addresses the case of jet breakout, where diverging magnetic flux surfaces yield strong MHD acceleration over a wider range of Lorentz factor.

  6. Zephyria Outflow Features

    NASA Technical Reports Server (NTRS)

    2004-01-01

    1 October 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows streamlined islands and a small cataract in an outflow channel system in the Zephyria region of Mars, south of Cerberus. The fluids responsible for creating these landforms flowed from the lower left (southwest) toward upper right (northeast). The fluids may have been water and mud or, some Mars scientists have argued, extremely fluid lava. The presence of a small cataract probably argues more strongly for a water and mud origin. This image is located near 3.8oN, 204.7oW. The picture covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from upper left.

  7. Driving Mechanisms for Molecular Outflows

    NASA Astrophysics Data System (ADS)

    Downes, Turlough P.

    Molecular outflows are observed to be closely associated with star formation. The cumulative momentum and the momentum injection rate in these outflows are important parameters in theories of star formation. The cumulative momentum in an outflow is a measure of the feed-back from star formation on molecular cloud turbulence. The level of turbulence in a cloud also effects the formation of further stars and, indeed, the survival of the cloud itself (e.g. [15]). In addition the rate of injection of momentum is an important constraint for theoretical models of outflows from young stars [10, 18]. Hence, while these outflows are interesting in themselves, it is also critical to understand their origin and behaviour as part of the general study of how stars themselves form.

  8. The contribution of quasar outflows to cosmological structure formation

    NASA Astrophysics Data System (ADS)

    Arav, Nahum

    2011-10-01

    A vast new discovery space is opened up by the high sensitivity of COS in the far UV. These new capabilities are ushering a revolution in the study of AGN outflows. We now have the ability to obtain high quality data on objects up to a redshift of about 1, providing access to ten times more {and better} diagnostic absorption lines than was possible with STIS {which could only observe outflows at z<0.05 with sufficient S/N}. These diagnostics will allow us to quantify how much do quasar outflow contribute to AGN feedback. On the way to this lofty goal, we'll be able to resolve important questions in the study of these outflows: Where are they situated within the host galaxy? What is their ionization equilibrium and chemical abundances? Unlike ground-based observations, COS data can yield the answers to all these questions for the most ubiquitous outflows, and therefore connect them to our developing understanding of cosmological structure formation.Our analysis of recent archived COS observations gives a concrete example for the above claims; including the first determination of the distance from the central source for a high-ionization outflow. Here we propose an archive program to look through the 520 COS G130M and G160M orbits of AGN archive observations, identify quasar outflows and publish the analyses of the best cases.

  9. Unsplit bipolar pulse forming line

    DOEpatents

    Rhodes, Mark A.

    2011-05-24

    A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  10. The dependence of galactic outflows on the properties and orientation of zCOSMOS galaxies at z ∼ 1

    SciTech Connect

    Bordoloi, R.; Lilly, S. J.; Hardmeier, E.; Carollo, C. M.; Contini, T.; Kneib, J.-P.; Fevre, O. Le; Garilli, B.; Renzini, A.; Scodeggio, M.; Zamorani, G.; Bardelli, S.; Bolzonella, M.; Bongiorno, A.; Caputi, K.; Cucciati, O.; De la Torre, S.; De Ravel, L.; Iovino, A.; and others

    2014-10-20

    We present an analysis of cool outflowing gas around galaxies, traced by Mg II absorption lines in the coadded spectra of a sample of 486 zCOSMOS galaxies at 1 ≤ z ≤ 1.5. These galaxies span a range of stellar masses (9.45 ≤ log{sub 10}[M {sub *}/M {sub ☉}] ≤ 10.7) and star formation rates (0.14 ≤ log{sub 10}[SFR/M {sub ☉} yr{sup –1}] ≤ 2.35). We identify the cool outflowing component in the Mg II absorption and find that the equivalent width of the outflowing component increases with stellar mass. The outflow equivalent width also increases steadily with the increasing star formation rate of the galaxies. At similar stellar masses, the blue galaxies exhibit a significantly higher outflow equivalent width as compared to red galaxies. The outflow equivalent width shows strong correlation with the star formation surface density (Σ{sub SFR}) of the sample. For the disk galaxies, the outflow equivalent width is higher for the face-on systems as compared to the edge-on ones, indicating that for the disk galaxies, the outflowing gas is primarily bipolar in geometry. Galaxies typically exhibit outflow velocities ranging from –150 km s{sup –1} ∼–200 km s{sup –1} and, on average, the face-on galaxies exhibit higher outflow velocity as compared to the edge-on ones. Galaxies with irregular morphologies exhibit outflow equivalent width as well as outflow velocities comparable to face on disk galaxies. These galaxies exhibit mass outflow rates >5-7 M {sub ☉} yr{sup –1} and a mass loading factor (η = M-dot {sub out}/SFR) comparable to the star formation rates of the galaxies.

  11. Contribution of alluvial groundwater to the outflow of mountainous catchments

    NASA Astrophysics Data System (ADS)

    Käser, Daniel; Hunkeler, Daniel

    2016-02-01

    Alluvial aquifers in mountainous regions cover typically a limited area. Their contribution to catchment storage and outflow is rarely isolated; alluvial groundwater discharge under gauging stations is generally assumed negligible; and hydrological models tend to lump alluvial storage with other units. The role of alluvial aquifers remains therefore unclear: can they contribute significantly to outflow when they cover a few percent of catchment area? Should they be considered a dynamic storage unit or merely a transmission zone? We address these issues based on the continuous monitoring of groundwater discharge, river discharge (one year), and aquifer storage (6 months) in the 6 km2 alluvial system of a 194 km2 catchment. River and groundwater outflow were measured jointly through "coupled gauging stations." The contribution of alluvial groundwater to outflow was highest at the outlet of a subcatchment (52 km2), where subsurface discharge amounted to 15% of mean annual outflow, and 85% of outflow during the last week of a drought. In this period, alluvial-aquifer depletion supported 75% of the subcatchment outflow and 35% of catchment outflow—thus 3% of the entire catchment supported a third of the outflow. Storage fluctuations occurred predominantly in the aquifer's upstream part, where heads varied over 6 m. Not only does this section act as a significant water source, but storage recovers also rapidly at the onset of precipitation. Storage dynamics were best conceptualized along the valley axis, rather than across the more conventional riparian-channel transect. Overall the contribution of alluvial aquifers to catchment outflow deserves more attention.

  12. Treatment of bipolar depression.

    PubMed

    Musetti, Laura; Del Grande, Claudia; Marazziti, Donatella; Dell'Osso, Liliana

    2013-08-01

    Depressive symptoms and episodes dominate the long-term course of bipolar disorder and are associated with high levels of disability and an increased risk of suicide. However, the treatment of bipolar depression has been poorly investigated in comparison with that of manic episodes and unipolar major depressive disorder. The goal of treatment in bipolar depression is not only to achieve full remission of acute symptoms, but also to avoid long-term mood destabilization and to prevent relapses. A depressive presentation of bipolar disorder may often delay the appropriate management and, thus, worsen the long-term outcome. In these cases, an accurate screening for diagnostic indicators of a possible bipolar course of the illness should guide the therapeutic choices, and lead to prognostic improvement. Antidepressant use is still the most controversial issue in the treatment of bipolar depression. Despite inconclusive evidence of efficacy and tolerability, this class of agents is commonly prescribed in acute and long-term treatment, often in combination with mood stabilizers. In this article, we review available treatment options for bipolar depression, and we shall provide some suggestions for the management of the different presentations of depression in the course of bipolar disorder. PMID:23391164

  13. The Ebers-Moll model for magnetic bipolar transistors

    NASA Astrophysics Data System (ADS)

    Fabian, Jaroslav; Žutić, Igor

    2005-03-01

    The equivalent electrical circuit of the Ebers-Moll-type is introduced for magnetic bipolar transistors. In addition to conventional diodes and current sources, the new circuit comprises two novel elements due to spin-charge coupling. A classification scheme of the operating modes of magnetic bipolar transistors in the low bias regime is presented.

  14. Auroral arcs and ion outflow

    NASA Astrophysics Data System (ADS)

    Maggiolo, Romain

    2016-04-01

    This presentation provides an overwiew of the chapter "Auroral Arcs and Ion Outflow" from the AGU book "Auroral Dynamics and Space Weather" (eds Y. Zhang and L. J. Paxton). This topic covers a wide range of domains, from auroral acceleration processes, auroral arc morphology and dynamics to global magnetosphere-ionosphere coupling and atmospheric erosion. This presentation mainly focuses on the observational properties of auroral ion outflow. Recent observations about their large-scale spatial distribution and link with auroral forms will be presented. Auroral ion outflow statistical dependence on solar and geomagnetic activity and its modulation by auroral dynamics at the timescale of substorms will also be discussed.

  15. Insight in bipolar disorder.

    PubMed

    Látalová, Klára

    2012-09-01

    Although there has been interest in insight in bipolar disorder, research has not been as developed as in schizophrenia. The Medline, Embase, and PsychInfo data bases were searched. The key words used in the search were "bipolar", "mania", "manic", "awareness", and "insight". Books, editorials, letters, and reports on pediatric subjects were excluded. Abstracts or full texts were screened for relevance. Better insight is associated with better adherence to treatment and better outcomes. Impairments of executive functions and memory, as well as higher severity of psychotic symptoms, are associated with impairments of insight. Insight is more impaired during an illness episode than during remission, in mixed than in pure manic episodes, in bipolar II than in bipolar I patients, in pure mania than in bipolar or unipolar depression. Psychosocial treatments improve insight and outcomes. There is a need for integration of quantitative assessment methods and their introduction into research and clinical practice. PMID:22101737

  16. Nuclear ashes and outflow in the eruptive star Nova Vul 1670.

    PubMed

    Kamiński, Tomasz; Menten, Karl M; Tylenda, Romuald; Hajduk, Marcin; Patel, Nimesh A; Kraus, Alexander

    2015-04-16

    CK Vulpeculae was observed in outburst in 1670-1672 (ref. 1), but no counterpart was seen until 1982, when a bipolar nebula was found at its location. Historically, CK Vul has been considered to be a nova (Nova Vul 1670), but its similarity to 'red transients', which are more luminous than classical novae and thought to be the results of stellar collisions, has re-opened the question of CK Vul's status. Red transients cool to resemble late M-type stars, surrounded by circumstellar material rich in molecules and dust. No stellar source has been seen in CK Vul, though a radio continuum source was identified at the expansion centre of the nebula. Here we report that CK Vul is surrounded by chemically rich molecular gas in the form of an outflow, as well as dust. The gas has peculiar isotopic ratios, revealing that CK Vul's composition was strongly enhanced by the nuclear ashes of hydrogen burning. The chemical composition cannot be reconciled with a nova or indeed any other known explosion. In addition, the mass of the surrounding gas is too large for a nova, though the conversion from observations of CO to a total mass is uncertain. We conclude that CK Vul is best explained as the remnant of a merger of two stars. PMID:25799986

  17. Kinematics of the Envelope and Two Bipolar Jets in the Class 0 Protostellar System L1157

    NASA Astrophysics Data System (ADS)

    Kwon, Woojin; Fernández-López, Manuel; Stephens, Ian W.; Looney, Leslie W.

    2015-11-01

    A massive envelope and a strong bipolar outflow are the two main structures characterizing the youngest protostellar systems. In order to understand the physical properties of a bipolar outflow and the relationship with those of the envelope, we obtained a mosaic map covering the whole bipolar outflow of the youngest protostellar system L1157 with about 5″ angular resolution in CO J = 2-1 using the Combined Array for Research in Millimeter-wave Astronomy. By utilizing these observations of the whole bipolar outflow, we estimate its physical properties and show that they are consistent with multiple jets. We also constrain a preferred precession direction. In addition, we observed the central envelope structure with 2″ resolution in the λ =1.3 and 3 mm continua and various molecular lines: C17O, C18O, 13CO, CS, CN, N2H+, CH3OH, H2O, SO, and SO2. All of the CO isotopes and CS, CN, and N2H+ have been detected and imaged. We marginally detected the features that can be interpreted as a rotating inner envelope in C17O and C18O and as an infalling outer envelope in N2H+. We also estimated the envelope and central protostellar masses and found that the dust-opacity spectral index changes with radius.

  18. Outflows of stars due to quasar feedback

    NASA Astrophysics Data System (ADS)

    Zubovas, Kastytis; Nayakshin, Sergei; Sazonov, Sergey; Sunyaev, Rashid

    2013-05-01

    Quasar feedback outflows are commonly invoked to drive gas out of galaxies in the early gas-rich epoch to terminate growth of galaxies. Here we present simulations that show that AGN feedback may drive not only gas but also stars out of their host galaxies under certain conditions. The mechanics of this process is as follows: (1) AGN-driven outflows accelerate and compress gas filling the host galaxy; (2) the accelerated dense shells become gravitationally unstable and form stars on radial trajectories. For the spherically symmetric initial conditions explored here, the black hole needs to exceed the host's Mσ mass by a factor of a few to accelerate the shells and the new stars to escape velocities. We discuss potential implications of these effects for the host galaxies: (i) radial mixing of bulge stars with the rest of the host; (ii) contribution of quasar outflows to galactic fountains as sources of high-velocity clouds; (iii) wholesale ejection of hypervelocity stars out of their hosts, giving rise to Type II supernovae on galactic outskirts, and contributing to reionization and metal enrichment of the Universe; (iv) bulge erosion and even complete destruction in extreme cases resulting in overweight or bulgeless SMBHs.

  19. CSO and CARMA Observations of L1157. II. Chemical Complexity in the Shocked Outflow

    NASA Astrophysics Data System (ADS)

    Burkhardt, Andrew M.; Dollhopf, Niklaus M.; Corby, Joanna F.; Carroll, P. Brandon; Shingledecker, Christopher N.; Loomis, Ryan A.; Booth, Shawn Thomas; Blake, Geoffrey A.; Herbst, Eric; Remijan, Anthony J.; McGuire, Brett A.

    2016-08-01

    L1157, a molecular dark cloud with an embedded Class 0 protostar possessing a bipolar outflow, is an excellent source for studying shock chemistry, including grain-surface chemistry prior to shocks, and post-shock, gas-phase processing. The L1157-B1 and B2 positions experienced shocks at an estimated ∼2000 and 4000 years ago, respectively. Prior to these shock events, temperatures were too low for most complex organic molecules to undergo thermal desorption. Thus, the shocks should have liberated these molecules from the ice grain-surfaces en masse, evidenced by prior observations of SiO and multiple grain mantle species commonly associated with shocks. Grain species, such as OCS, CH3OH, and HNCO, all peak at different positions relative to species that are preferably formed in higher-velocity shocks or repeatedly shocked material, such as SiO and HCN. Here, we present high spatial resolution (∼3″) maps of CH3OH, HNCO, HCN, and HCO+ in the southern portion of the outflow containing B1 and B2, as observed with Combined Array for Research in Millimeter-Wave Astronomy. The HNCO maps are the first interferometric observations of this species in L1157. The maps show distinct differences in the chemistry within the various shocked regions in L1157B. This is further supported through constraints of the molecular abundances using the non-LTE code radex. We find that the east/west chemical differentiation in C2 may be explained by the contrast of the shock’s interaction with either cold, pristine material or warm, previously shocked gas, as seen in enhanced HCN abundances. In addition, the enhancement of the HNCO abundance toward the the older shock, B2, suggests the importance of high-temperature O-chemistry in shocked regions.

  20. CSO and CARMA Observations of L1157. II. Chemical Complexity in the Shocked Outflow

    NASA Astrophysics Data System (ADS)

    Burkhardt, Andrew M.; Dollhopf, Niklaus M.; Corby, Joanna F.; Carroll, P. Brandon; Shingledecker, Christopher N.; Loomis, Ryan A.; Booth, Shawn Thomas; Blake, Geoffrey A.; Herbst, Eric; Remijan, Anthony J.; McGuire, Brett A.

    2016-08-01

    L1157, a molecular dark cloud with an embedded Class 0 protostar possessing a bipolar outflow, is an excellent source for studying shock chemistry, including grain-surface chemistry prior to shocks, and post-shock, gas-phase processing. The L1157-B1 and B2 positions experienced shocks at an estimated ˜2000 and 4000 years ago, respectively. Prior to these shock events, temperatures were too low for most complex organic molecules to undergo thermal desorption. Thus, the shocks should have liberated these molecules from the ice grain-surfaces en masse, evidenced by prior observations of SiO and multiple grain mantle species commonly associated with shocks. Grain species, such as OCS, CH3OH, and HNCO, all peak at different positions relative to species that are preferably formed in higher-velocity shocks or repeatedly shocked material, such as SiO and HCN. Here, we present high spatial resolution (˜3″) maps of CH3OH, HNCO, HCN, and HCO+ in the southern portion of the outflow containing B1 and B2, as observed with Combined Array for Research in Millimeter-Wave Astronomy. The HNCO maps are the first interferometric observations of this species in L1157. The maps show distinct differences in the chemistry within the various shocked regions in L1157B. This is further supported through constraints of the molecular abundances using the non-LTE code radex. We find that the east/west chemical differentiation in C2 may be explained by the contrast of the shock’s interaction with either cold, pristine material or warm, previously shocked gas, as seen in enhanced HCN abundances. In addition, the enhancement of the HNCO abundance toward the the older shock, B2, suggests the importance of high-temperature O-chemistry in shocked regions.

  1. Source-diagnostic dual-isotope composition and optical properties of water-soluble organic carbon and elemental carbon in the South Asian outflow intercepted over the Indian Ocean

    NASA Astrophysics Data System (ADS)

    Bosch, Carme; Andersson, August; Kirillova, Elena N.; Budhavant, Krishnakant; Tiwari, Suresh; Praveen, P. S.; Russell, Lynn M.; Beres, Nicholas D.; Ramanathan, Veerabhadran; Gustafsson, Örjan

    2014-10-01

    The dual carbon isotope signatures and optical properties of carbonaceous aerosols have been investigated simultaneously for the first time in the South Asian outflow during an intensive campaign at the Maldives Climate Observatory on Hanimaadhoo (MCOH) (February and March 2012). As one component of the Cloud Aerosol Radiative Forcing Dynamics Experiment, this paper reports on the sources and the atmospheric processing of elemental carbon (EC) and water-soluble organic carbon (WSOC) as examined by a dual carbon isotope approach. The radiocarbon (Δ14C) data show that WSOC has a significantly higher biomass/biogenic contribution (86 ± 5%) compared to EC (59 ± 4%). The more 13C-enriched signature of MCOH-WSOC (-20.8 ± 0.7‰) compared to MCOH-EC (-25.8 ± 0.3‰) and megacity Delhi WSOC (-24.1 ± 0.9‰) suggests that WSOC is significantly more affected by aging during long-range transport than EC. The δ13C-Δ14C signal suggests that the wintertime WSOC intercepted over the Indian Ocean largely represents aged primary biomass burning aerosols. Since light-absorbing organic carbon aerosols (Brown Carbon (BrC)) have recently been identified as potential contributors to positive radiative forcing, optical properties of WSOC were also investigated. The mass absorption cross section of WSOC (MAC365) was 0.5 ± 0.2 m2 g-1 which is lower than what has been observed at near-source sites, indicating a net decrease of WSOC light-absorption character during long-range transport. Near-surface WSOC at MCOH accounted for ~1% of the total direct solar absorbance relative to EC, which is lower than the BrC absorption inferred from solar spectral observations of ambient aerosols, suggesting that a significant portion of BrC might be included in the water-insoluble portion of organic aerosols.

  2. Bipolar Disorder in Children

    PubMed Central

    2014-01-01

    Although bipolar disorder historically was thought to only occur rarely in children and adolescents, there has been a significant increase in children and adolescents who are receiving this diagnosis more recently (Carlson, 2005). Nonetheless, the applicability of the current bipolar disorder diagnostic criteria for children, particularly preschool children, remains unclear, even though much work has been focused on this area. As a result, more work needs to be done to further the understanding of bipolar symptoms in children. It is hoped that this paper can assist psychologists and other health service providers in gleaning a snapshot of the literature in this area so that they can gain an understanding of the diagnostic criteria and other behaviors that may be relevant and be informed about potential approaches for assessment and treatment with children who meet bipolar disorder criteria. First, the history of bipolar symptoms and current diagnostic criteria will be discussed. Next, assessment strategies that may prove helpful for identifying bipolar disorder will be discussed. Then, treatments that may have relevance to children and their families will be discussed. Finally, conclusions regarding work with children who may have a bipolar disorder diagnosis will be offered. PMID:24800202

  3. Shining a light on galactic outflows: photoionized outflows

    NASA Astrophysics Data System (ADS)

    Chisholm, John; Tremonti, Christy A.; Leitherer, Claus; Chen, Yanmei; Wofford, Aida

    2016-04-01

    We study the ionization structure of galactic outflows in 37 nearby, star-forming galaxies with the Cosmic Origins Spectrograph on the Hubble Space Telescope. We use the O I, Si II, Si III, and Si IV ultraviolet absorption lines to characterize the different ionization states of outflowing gas. We measure the equivalent widths, line widths, and outflow velocities of the four transitions, and find shallow scaling relations between them and galactic stellar mass and star formation rate. Regardless of the ionization potential, lines of similar strength have similar velocities and line widths, indicating that the four transitions can be modelled as a comoving phase. The Si equivalent width ratios (e.g. Si IV/Si II) have low dispersion, and little variation with stellar mass; while ratios with O I and Si vary by a factor of 2 for a given stellar mass. Photoionization models reproduce these equivalent width ratios, while shock models under predict the relative amount of high ionization gas. The photoionization models constrain the ionization parameter (U) between -2.25 < log (U) < -1.5, and require that the outflow metallicities are greater than 0.5 Z⊙. We derive ionization fractions for the transitions, and show that the range of ionization parameters and stellar metallicities leads to a factor of 1.15-10 variation in the ionization fractions. Historically, mass outflow rates are calculated by converting a column density measurement from a single metal ion into a total hydrogen column density using an ionization fraction, thus mass outflow rates are sensitive to the assumed ionization structure of the outflow.

  4. Review of Evidence for Use of Antidepressants in Bipolar Depression

    PubMed Central

    McInerney, Shane J.

    2014-01-01

    Objective: Depressive episodes predominate over the course of bipolar disorder and cause considerable functional impairment. Antidepressants are frequently prescribed in the treatment of bipolar depression, despite concerns about efficacy and risk of switching to mania. This review provides a critical examination of the evidence for and against the use of antidepressants in bipolar depression. Data Sources: English-language peer-reviewed literature and evidence-based guidelines published between January 1, 1980, and March 2014, were identified using PubMed, MEDLINE, PsycINFO/PsycLIT, and EMBASE. All searches contained the terms antidepressants, bipolar depression, depressive episodes in bipolar disorder, and treatment guidelines for bipolar depression. Meta-analyses, randomized controlled trials, systematic reviews, and practice guidelines were included. Bibliographies from these publications were used to identify additional articles of interest. Data Extraction: Studies involving treatment of bipolar depression with antidepressant monotherapy, adjunctive use of antidepressant with a mood stabilizer, and meta-analysis of such studies combined were reviewed. Conclusions: The body of evidence on the use of antidepressant monotherapy to treat patients with bipolar depression is contentious, but the recommendations from evidence-based guidelines do not support antidepressant monotherapy for bipolar depression. Only when mood stabilizer or atypical antipsychotic monotherapy has failed should adjunctive treatment with an antidepressant be considered. PMID:25667812

  5. Bipolar fuel cell

    DOEpatents

    McElroy, James F.

    1989-01-01

    The present invention discloses an improved fuel cell utilizing an ion transporting membrane having a catalytic anode and a catalytic cathode bonded to opposite sides of the membrane, a wet-proofed carbon sheet in contact with the cathode surface opposite that bonded to the membrane and a bipolar separator positioned in electrical contact with the carbon sheet and the anode of the adjacent fuel cell. Said bipolar separator and carbon sheet forming an oxidant flowpath, wherein the improvement comprises an electrically conductive screen between and in contact with the wet-proofed carbon sheet and the bipolar separator improving the product water removal system of the fuel cell.

  6. On the physical origin of AGN outflow driving mechanisms

    NASA Astrophysics Data System (ADS)

    Ishibashi, Wako

    2016-07-01

    Super-massive black holes in active galactic nuclei (AGN) respond to the accretion process by feeding back energy and momentum into the surrounding environment. Galaxy-scale outflows are thought to provide the physical link connecting the small scales of the central black hole to the large scales of the host galaxy. Such powerful outflows are now starting to be commonly observed, and have been considered as a proof of AGN feedback in action. However, the physical origin of the mechanism driving the observed outflows is still unclear, and whether it is due to energy-driving or radiation-driving is a source of much debate in the literature. We consider AGN feedback driven by radiation pressure on dust, and show that AGN radiative feedback is capable of driving powerful outflows on galactic scales. In particular, we can obtain outflowing shells with high velocity and large momentum flux, by properly taking into account the effects of radiation trapping. Alternatively, the observed outflow characteristics may be significantly biased by AGN variability. I will discuss the resulting implications in the global context of black hole accretion-AGN feedback coupling.

  7. Identifying the Main Driver of Active Region Outflows

    NASA Astrophysics Data System (ADS)

    Baker, D.; van Driel-Gesztelyi, L.; Mandrini, C. H.; Démoulin, P.; Murray, M. J.

    2012-08-01

    Hinode's EUV Imaging Spectrometer (EIS) has discovered ubiquitous outflows of a few to 50 km s-1 from active regions (ARs). The characteristics of these outflows are very curious in that they are most prominent at the AR boundary and appear over monopolar magnetic areas. They are linked to strong non-thermal line broadening and are stronger in hotter EUV lines. The outflows persist for at least several days. Whereas red-shifted down flows observed in AR closed loops are well understood, to date there is no general consensus for the mechanism(s) driving blue-shifted AR-related outflows. We use Hinode EIS and X-Ray Telescope observations of AR 10942 coupled with magnetic modeling to demonstrate for the first time that the outflows originate from specific locations of the magnetic topology where field lines display strong gradients of magnetic connectivity, namely quasi-separatrix layers (QSLs), or in the limit of infinitely thin QSLs, separatrices. The strongest AR outflows were found to be in the vicinity of QSL sections located over areas of strong magnetic field. We argue that magnetic reconnection at QSLs, separating closed field lines of the AR and either large-scale externally connected or ‘open’ field lines, is a viable mechanism for driving AR outflows which are potentially sources of the slow solar wind. In fact, magnetic reconnection along QSLs (including separatricies) is the first theory to explain the most puzzling characteristics of the outflows, namely their occurrence over monopolar areas at the periphery of ARs and their longevity.

  8. The Detection of [C i] in Molecular Outflows Associated with Young Stellar Objects

    NASA Astrophysics Data System (ADS)

    Walker, Christopher K.; Narayanan, Gopal; Buettgenbach, Thomas H.; Carlstrom, John E.; Keene, Jocelyn; Phillips, T. G.

    1993-10-01

    The first observations of atomic carbon in molecular outflows are presented. Most of the outflow regions show similar [C I] and 13CO line profiles suggesting the [C I] emission from outflow sources traces the same volume of gas as the CO emission, as previous studies have suggested for molecular clouds in general. The [C I] and CO column densities for the 11 sources surveyed are computed over wing and line center velocities. If the [C I] column densities derived from line center velocities are probing conditions in the ambient cloud in the vicinity of the infrared source, then a comparison of these values indicates the carbon abundance in the low-velocity component of the outflows is essentially the same as in the ambient cloud; there is no evidence for shock enhancement of [C 1] in the swept-up material. A map of the [C I] emission from the central arcminute of the luminous DR 21 outflow is presented. The [C I] emission is detected from the two CO outflow lobes; [C I] emission from the southwest lobe appears as a limb-brightened, conical shell. Outflow parameters derived from [C I] are consistent with those derived from CO, suggesting the [C I] emission arises from ambient cloud material swept-up by the outflow. The presence of carbon in the swept-up component of the outflows indicates that gas phase carbon is present deep within molecular clouds and is not confined solely to surface layers.

  9. Mid­Infrared Imaging of the Bipolar Planetary Nebula M2-­9 from SOFIA

    NASA Astrophysics Data System (ADS)

    Sahai, R.; Werner, M. W.; Davis, J.; Livingston, J.; Lykou, F.; de Buizer, J.; Morris, M.; Keller, L.; Adams, J.; Gull, G.; Henderson, C.; Herter, T.; Schoenwald, J.

    2014-04-01

    We have imaged the bi-polar planetary nebula M2-9 using SOFIA's FORCAST instrument in six wavelength bands between 6.6 and 37.1 micron. A bright central point source, unresolved with SOFIA's ~4" beam, is seen at each wavelength, and the extended bipolar lobes are clearly seen at 19.7 μm and beyond. The photometry between 10 and 25 micron is well fit by a model of the type previously proposed for this source by Lykou et al and Chesneau et al. The principal new results in this paper relate to the distribution and properties of the dust that emits the infrared radiation. In particular, a considerable fraction of this material is spread uniformly through the lobes, although the dust density does increase at the sharp outer edge seen in higher resolution optical images of M2-9. The dust grain population in the source is unusual in that small (<0.1 micron) and large (>1 micron) particles appear to be present in roughly equal quantities by mass. We suggest that collisional processing within the bipolar outflow plays an important role in determining the particle size distribution. These early results show the promise of the SOFIA airborne observatory as a platform for studying planetary nebulae. This work is based on observations made with the NASA/DLR Stratospheric Observatory for Infrared Astronomy (SOFIA), operated by USRA and DSI. Portions of the work were carried out at the Jet Propulsion Laboratory, operated by the California Institute of Technology under a contract with NASA.

  10. APEX CO (9-8) MAPPING OF AN EXTREMELY HIGH VELOCITY AND JET-LIKE OUTFLOW IN A HIGH-MASS STAR-FORMING REGION

    SciTech Connect

    Qiu Keping; Wyrowski, Friedrich; Menten, Karl M.; Guesten, Rolf; Leurini, Silvia; Leinz, Christian

    2011-12-10

    Atacama Pathfinder Experiment (APEX) mapping observations in CO (9-8) and (4-3) toward a high-mass star-forming region, NGC 6334 I, are presented. The CO (9-8) map has a 6.''4 resolution, revealing a {approx}0.5 pc, jet-like, and bipolar outflow. This is the first map of a molecular outflow in a THz line. The CO (9-8) and (4-3) lines arising from the outflow lobes both show extremely high velocity line wings, and their ratios indicate a gas temperature greater than 100 K and a density higher than 10{sup 4} cm{sup -3}. The spatial-velocity structure of the CO (9-8) data is typical of a bow-shock-driven flow, which is consistent with the association between the bipolar outflow and the infrared bow-shaped tips. In short, the observations unveil a highly excited and collimated component in a bipolar outflow that is powered by a high-mass protostar, and provide insights into the driving mechanism of the outflow. Meanwhile, the observations demonstrate that high-quality mapping observations can be performed with the new THz receiver on APEX.

  11. RADIATION MAGNETOHYDRODYNAMICS SIMULATION OF PROTO-STELLAR COLLAPSE: TWO-COMPONENT MOLECULAR OUTFLOW

    SciTech Connect

    Tomida, Kengo; Tomisaka, Kohji; Ohsuga, Ken; Matsumoto, Tomoaki; Machida, Masahiro N.; Saigo, Kazuya E-mail: tomisaka@th.nao.ac.jp E-mail: masahiro.machida@nao.ac.jp E-mail: matsu@hosei.ac.jp

    2010-05-01

    We perform a three-dimensional nested-grid radiation magnetohydrodynamics (RMHD) simulation with self-gravity to study the early phase of the low-mass star formation process from a rotating molecular cloud core to a first adiabatic core just before the second collapse begins. Radiation transfer is implemented with the flux-limited diffusion approximation, operator-splitting, and implicit time integrator. In the RMHD simulation, the outer region of the first core attains a higher entropy and its size is larger than that in the magnetohydrodynamics simulations with the barotropic approximation. Bipolar molecular outflow consisting of two components is driven by magnetic Lorentz force via different mechanisms, and shock heating by the outflow is observed. Using the RMHD simulation we can predict and interpret the observed properties of star-forming clouds, first cores, and outflows with millimeter/submillimeter radio interferometers, especially the Atacama Large Millimeter/submillimeter Array.

  12. Herbig-Haro objects in the receding lobe of the L 1551 outflow

    NASA Technical Reports Server (NTRS)

    Graham, J. A.; Rubin, Vera C.

    1992-01-01

    A spectrum has been obtained of two Herbig-Haro objects which are seen against the receding lobe of the bipolar outflow within the dark cloud Lynds 1551. Positive heliocentric velocities up to 90 km/s have been measured from the H-alpha line which point to an association of these emission knots with the embedded infrared source L 1551-IRS 5 rather than with other young stellar objects in this part of the sky. There is a velocity range of 50-100 km/s within each object. (S II) lambda 6716 is also detected at a strength of about 50 pct of H-alpha. Along the entire length of the slit there is broad H-alpha emission with strength about four times that normally seen in emission from the night sky. This feature partially resolves into two components, one of which we suggest is from the general Galactic field, and the other from extended bow-shock emission.

  13. Origin of outflows and winds

    NASA Technical Reports Server (NTRS)

    Koenigl, Arieh; Ruden, Steven P.

    1993-01-01

    Recent developments concerning the accretion-outflow connection and the role of magnetic fields are examined. It is argued that the weakly ionized wind most likely represents an MHD outflow driven centrifugally from the disk surfaces or from the boundary between the disk and the star. Specific wind models for each of these alternatives are presented, and it is contended that both provide a natural explanation of the observed correlation between accretion and outflow. The kinematic, thermal, and chemical wind properties predicted by these models are described and their observational implications are considered. It is suggested that the wind characteristics may be reflected in the observed forbidden line and IR continuum emission of T Tauri stars and in the measured abundances of various molecular species.

  14. Mediterranean Outflow Mixing and Dynamics

    NASA Astrophysics Data System (ADS)

    Price, James F.; O'Neil Baringer, Molly; Lueck, Rolf G.; Johnson, Gregory C.; Ambar, Isabel; Parrilla, Gregorio; Cantos, Alain; Kennelly, Maureen A.; Sanford, Thomas B.

    1993-02-01

    The Mediterranean Sea produces a salty, dense outflow that is strongly modified by entrainment as it first begins to descend the continental slope in the eastern Gulf of Cadiz. The current accelerates to 1.3 meters per second, which raises the internal Froude number above 1, and is intensely turbulent through its full thickness. The outflow loses about half of its density anomaly and roughly doubles its volume transport as it entrains less saline North Atlantic Central water. Within 100 kilometers downstream, the current is turned by the Coriolis force until it flows nearly parallel to topography in a damped geostrophic balance. The mixed Mediterranean outflow continues westward, slowly descending the continental slope until it becomes neutrally buoyant in the thermocline where it becomes an important water mass.

  15. Mediterranean outflow mixing and dynamics.

    PubMed

    Price, J F; Baringer, M O; Lueck, R G; Johnson, G C; Ambar, I; Parrilla, G; Cantos, A; Kennelly, M A; Sanford, T B

    1993-02-26

    The Mediterranean Sea produces a salty, dense outflow that is strongly modified by entrainment as it first begins to descend the continental slope in the eastern Gulf of Cadiz. The current accelerates to 1.3 meters per second, which raises the internal Froude number above 1, and is intensely turbulent through its full thickness. The outflow loses about half of its density anomaly and roughly doubles its volume transport as it entrains less saline North Atlantic Central water. Within 100 kilometers downstream, the current is turned by the Coriolis force until it flows nearly parallel to topography in a damped geostrophic balance. The mixed Mediterranean outflow continues westward, slowly descending the continental slope until it becomes neutrally buoyant in the thermocline where it becomes an important water mass. PMID:17732247

  16. High resolution imaging of the outflow channels on Mars

    NASA Astrophysics Data System (ADS)

    Davatzes, A. K.; Gulick, V. C.

    2008-12-01

    We report observations of the outflow channels on Mars from HiRISE images in MRO's first Martian year. Several hundred images of the outflow channels on Mars have been collected to date from HiRISE, as well as coordinated images with CTX and CRISM. Depositional features, such as slackwater deposits and small bedforms that are expected to be visible at the resolution of HiRISE have not yet been observed, largely due to post-fluvial modification of the channels. Many of the channels have been subsequently covered by a thin layer of lava, ash, dust, or lineated valley fill. Although altered slightly by later aeolian modification, Ares Valles and Kasei Valles preserve much of the original fluvial erosional forms, particularly cataracts and longitudinal grooves that can be used to infer the mechanics of the flow. Cataracts, steep knickpoints in the large outflow channels, were once large waterfalls on the Martian surface. These have been observed in all of the larger outflow systems, including Kasai, Athabasca, Mangala, and Reull Valles. High resolution imaging shows that all of the cataract systems have multiple generations of erosion, with smaller subchannels within the cataract system. Based on the length of the recession and the morphological evidence most of the large channels experienced multiple flooding events or pulses. The tectonically sourced outflow channels, such as Athabasca and Mangala Valles, show sourcing at regions of complex fault geometries, specifically at fault relays. In terrestrial systems, relays tend to be regions of concentrated stress that can produce dilation manifested as high joint density, as well as point sources for hydrothermal outflow on Earth. Athabasca and Mangala Valles, sourced proximal to large volcanic centers, may have been regions of major hydrothermal activity in the past.

  17. The collimated outflows of the planetary nebula Hu 1-2: proper motion and radial velocity measurements

    NASA Astrophysics Data System (ADS)

    Miranda, L. F.; Blanco, M.; Guerrero, M. A.; Riera, A.

    2012-04-01

    Hu 1-2 is a planetary nebula that contains an isolated knot located north-west of the main nebula, which could be related to a collimated outflow. We present a subarcsecond Hα+[N II] image and a high-resolution, long-slit spectrum of Hu 1-2 that allow us to identify the south-eastern counterpart of the north-western knot and to establish their high-velocity (>340 km s-1), collimated bipolar outflow nature. The detection of the north-western knot in Palomar Observatory Sky Atlas (POSS) red plates allows us to carry out a proper motion analysis by combining three POSS red plates and two narrow-band Hα+[N II] CCD images, with a time baseline of ≃57 yr. A proper motion of 20 ± 6 mas yr-1 along position angle 312°± 15° and a dynamical age of 1375? yr are obtained for the bipolar outflow. The measured proper motion and the spatio-kinematical properties of the bipolar outflow yield a lower limit of 2.7 kpc for the distance to Hu 1-2. The Andalucia Faint Object Spectrograph and Camera (ALFOSC) is provided by the Instituto de Astrofísica de Andalucía (IAA) under a joint agreement with the University of Copenhagen and NOTSA. The IACUB uncrossed echelle spectrograph was built in a collaboration between the IAC and the Queen's University of Belfast.

  18. Evidence for a chemically differentiated outflow in Mrk 231

    NASA Astrophysics Data System (ADS)

    Lindberg, J. E.; Aalto, S.; Muller, S.; Martí-Vidal, I.; Falstad, N.; Costagliola, F.; Henkel, C.; van der Werf, P.; García-Burillo, S.; González-Alfonso, E.

    2016-03-01

    Aims: Our goal is to study the chemical composition of the outflows of active galactic nuclei and starburst galaxies. Methods: We obtained high-resolution interferometric observations of HCN and HCO+J = 1 → 0 and J = 2 → 1 of the ultra-luminous infrared galaxy Mrk 231 with the IRAM Plateau de Bure Interferometer. We also use previously published observations of HCN and HCO+J = 1 → 0 and J = 3 → 2, and HNC J = 1 → 0 in the same source. Results: In the line wings of the HCN, HCO+, and HNC emission, we find that these three molecular species exhibit features at distinct velocities which differ between the species. The features are not consistent with emission lines of other molecular species. Through radiative transfer modelling of the HCN and HCO+ outflow emission we find an average abundance ratio X(HCN) /X(HCO+) ≳ 1000. Assuming a clumpy outflow, modelling of the HCN and HCO+ emission produces strongly inconsistent outflow masses. Conclusions: Both the anti-correlated outflow features of HCN and HCO+ and the different outflow masses calculated from the radiative transfer models of the HCN and HCO+ emission suggest that the outflow is chemically differentiated. The separation between HCN and HCO+ could be an indicator of shock fronts present in the outflow, since the HCN/HCO+ ratio is expected to be elevated in shocked regions. Our result shows that studies of the chemistry in large-scale galactic outflows can be used to better understand the physical properties of these outflows and their effects on the interstellar medium in the galaxy. Based on observations with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).Reduced datacubes as FITS files are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/587/A15

  19. Depression and Bipolar Support Alliance

    MedlinePlus

    ... events Visit the podcast archive Mood Disorders Depression Bipolar Disorder Anxiety Screening Center Co-occurring Illnesses/Disorders Related ... for Your Patients Information about Depression Information about Bipolar Disorder Wellness Tools DBSA Support Groups Active Research Studies ...

  20. Bipolar Affective Disorder and Migraine

    PubMed Central

    Engmann, Birk

    2012-01-01

    This paper consists of a case history and an overview of the relationship, aetiology, and treatment of comorbid bipolar disorder migraine patients. A MEDLINE literature search was used. Terms for the search were bipolar disorder bipolar depression, mania, migraine, mood stabilizer. Bipolar disorder and migraine cooccur at a relatively high rate. Bipolar II patients seem to have a higher risk of comorbid migraine than bipolar I patients have. The literature on the common roots of migraine and bipolar disorder, including both genetic and neuropathological approaches, is broadly discussed. Moreover, bipolar disorder and migraine are often combined with a variety of other affective disorders, and, furthermore, behavioural factors also play a role in the origin and course of the diseases. Approach to treatment options is also difficult. Several papers point out possible remedies, for example, valproate, topiramate, which acts on both diseases, but no first-choice treatments have been agreed upon yet. PMID:22649454

  1. Lightweight bipolar storage battery

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1992-01-01

    An apparatus [10] is disclosed for a lightweight bipolar battery of the end-plate cell stack design. Current flow through a bipolar cell stack [12] is collected by a pair of copper end-plates [16a,16b] and transferred edgewise out of the battery by a pair of lightweight, low resistance copper terminals [28a,28b]. The copper terminals parallel the surface of a corresponding copper end-plate [16a,16b] to maximize battery throughput. The bipolar cell stack [12], copper end-plates [16a,16b] and copper terminals [28a,28b] are rigidly sandwiched between a pair of nonconductive rigid end-plates [20] having a lightweight fiber honeycomb core which eliminates distortion of individual plates within the bipolar cell stack due to internal pressures. Insulating foam [30] is injected into the fiber honeycomb core to reduce heat transfer into and out of the bipolar cell stack and to maintain uniform cell performance. A sealed battery enclosure [ 22] exposes a pair of terminal ends [26a,26b] for connection with an external circuit.

  2. Molecular outflows in starburst nuclei

    NASA Astrophysics Data System (ADS)

    Roy, Arpita; Nath, Biman B.; Sharma, Prateek; Shchekinov, Yuri

    2016-08-01

    Recent observations have detected molecular outflows in a few nearby starburst nuclei. We discuss the physical processes at work in such an environment in order to outline a scenario that can explain the observed parameters of the phenomenon, such as the molecular mass, speed and size of the outflows. We show that outflows triggered by OB associations, with NOB ≥ 105 (corresponding to a star formation rate (SFR)≥1 M⊙ yr-1 in the nuclear region), in a stratified disk with mid-plane density n0 ˜ 200-1000 cm-3 and scale height z0 ≥ 200(n0/102 cm-3)-3/5 pc, can form molecules in a cool dense and expanding shell. The associated molecular mass is ≥107 M⊙ at a distance of a few hundred pc, with a speed of several tens of km s-1. We show that a SFR surface density of 10 ≤ ΣSFR ≤ 50 M⊙ yr-1 kpc-2 favours the production of molecular outflows, consistent with observed values.

  3. The Geometry of Quasar Outflows

    NASA Astrophysics Data System (ADS)

    Ganguly, Rajib

    2012-10-01

    Quasar outflows are important for understanding the accretion and growth processes of the central black hole, but also potentially play a role in feedback to the galaxy, halting star formation and infall of gas. A big uncertainty lies in the geometry and density of these outflows, especially as a function of ionization and velocity. We aim to tackle this using the archival COS M grating spectra of 266 quasars. We separate the geometry of outflows into two parts: the solid angle subtended around the black hole, and the distance of the outflow from the central engine. Large numbers of quasars with high resolution spectra are required for each aspect of this statistical investigation. First, we will determine which/how many absorption-line systems are intrinsic through both partial covering methods and statistical assessments. Second, we will consider the incidence of intrinsic absorbers as a function of quasar property {e.g., radio-loudness, SED shape, black hole mass, bolometric luminosity}. This will reveal what determines the solid angle. This can only be done at moderate redshifts where quasars with a larger range of properties are observable, and hence requires HST/COS. Third, we will use the wide range of diagnostic lines to constrain the physical conditions of the absorbers. We will target the CIII*1175 complex and apply photoionization models to constrain the densities and ionization parameters. This will provide the largest set yet of intrinsic absorbers with systematic distance constraints. In tandem with the solid angles, this work will inform models regarding the geometry of quasar outflows.

  4. Hot outflows in galaxy clusters

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, C. C.; McNamara, B. R.

    2015-10-01

    The gas-phase metallicity distribution has been analysed for the hot atmospheres of 29 galaxy clusters using Chandra X-ray Observatory observations. All host brightest cluster galaxies (BCGs) with X-ray cavity systems produced by radio AGN. We find high elemental abundances projected preferentially along the cavities of 16 clusters. The metal-rich plasma was apparently lifted out of the BCGs with the rising X-ray cavities (bubbles) to altitudes between twenty and several hundred kiloparsecs. A relationship between the maximum projected altitude of the uplifted gas (the `iron radius') and jet power is found with the form R_Fe ∝ P_jet^{0.45}. The estimated outflow rates are typically tens of solar masses per year but exceed 100 M⊙ yr- 1 in the most powerful AGN. The outflow rates are 10-20 per cent of the cooling rates, and thus alone are unable to offset a cooling inflow. Nevertheless, hot outflows effectively redistribute the cooling gas and may play a significant role at regulating star formation and AGN activity in BCGs and presumably in giant elliptical galaxies. The metallicity distribution overall can be complex, perhaps due to metal-rich gas returning in circulation flows or being blown around in the hot atmospheres. Roughly 15 per cent of the work done by the cavities is expended lifting the metal-enriched gas, implying their nuclear black holes have increased in mass by at least ˜107-109 M⊙. Finally, we show that hot outflows can account for the broad, gas-phase metallicity distribution compared to the stellar light profiles of BCGs, and we consider a possible connection between hot outflows and cold molecular gas flows discovered in recent Atacama Large Millimeter Array observations.

  5. Evidence for Collimated Outflow from Sgr A*?

    NASA Astrophysics Data System (ADS)

    Yusef-Zadeh, Farhad; Arendt, R.; Bushouse, H.; Cotton, W.; Haggard, D.; Heinke, C.; Roberts, D. A.; Royster, M.; Wardle, M.

    2012-05-01

    The compact radio source Sgr A* is considered to be coincident with a 4 million solar mass black hole at the dynamical center of the Galaxy. There has been a considerable debate as to whether the jet or the accretion flow model can explain the broad band spectrum of the emission. Here, we present high resolution radio, X-ray continuum and FeII line images showing new structural details within the inner arcminute (2.4pc) of Sgr A*. On a small scale, we find a chain of radio blobs which appear to be emanating from Sgr A*. These blobs are detected beyond the inner 1" of Sgr A* and are distributed along a continuous linear feature that is tilted by 28 degrees with respect to the Galactic plane. In linear polarization images at 3.6cm, three blobs of emission have been detected symmetrically about 1' from Sgr A*. The morphology and polarization of the linear feature suggest a jet outflow from Sgr A*, punching through the orbiting ionized gas and producing X-ray emission as well as a hot bubble of FeIII/FeII line emission. On a scale of about 15pc, we also note a collection of large-scale radio and X-ray "streamers" in the direction perpendicular to the Galactic plane. This complex structure consists of nonthermal and thermal continuum features as well as molecular clouds traced at infrared wavelengths. The base of the outflowing gas appears to be confined by the 2-pc molecular ring, within which a cluster of massive stars lie. These features suggest star-burst driven outflow may be responsible for this energetic activity.

  6. VizieR Online Data Catalog: Fermi sources with massive YSO associations (Munar-Adrover+, 2011)

    NASA Astrophysics Data System (ADS)

    Munar-Adrover, P.; Paredes, J. M.; Romero, G. E.

    2011-09-01

    Massive protostars have associated bipolar outflows that can produce strong shocks when they interact with the surrounding medium. At these shocks, particles can be accelerated up to relativistic energies. Relativistic electrons and protons can then produce gamma-ray emission, as some theoretical models predict. To identify young galactic objects that may emit gamma rays, we crossed the Fermi First Year Catalog with some catalogs of known massive young stellar objects (MYSOs), early type stars, and OB associations, and we implemented Monte Carlo simulations to find the probability of chance coincidences. We obtained a list of massive MYSOs that are spatially coincident with Fermi sources. (4 data files).

  7. Serotonergic Dysfunction in Patients with Bipolar Disorder Assessed by the Loudness Dependence of the Auditory Evoked Potential

    PubMed Central

    Lee, Kyung-Sang; Park, Young-Min

    2012-01-01

    Objective The loudness dependence of the auditory evoked potential (LDAEP) is suggested to be a marker of serotonin system function. This study explored the LDAEP of multiple mood statuses (depression, mania, and euthymia) and its clinical implication in bipolar disorder patients. Methods A total of 89 subjects, comprising 35 patients with bipolar disorder, 32 patients with schizophrenia, and 22 healthy controls were evaluated. The bipolar disorder cases comprised 10 depressed patients, 15 patients with mania, and 10 euthymic patients. The N1/P2 peak-to-peak amplitudes were measured at 5 stimulus intensities, and the LDAEP was calculated as the slope of the linear regression. Both cortical and source LDAEP values were calculated. Results LDAEP varied according to mood statuses, and was significantly stronger in cases of euthymia, depression, and mania. Cortical LDAEP was significantly stronger in patients with bipolar euthymia compared with schizophrenia, stronger in bipolar depression than in schizophrenia, stronger in healthy controls than in schizophrenia patients, and stronger in healthy controls than in patients with bipolar mania. Source LDAEP was significantly stronger in patients with bipolar euthymia, bipolar depression, and bipolar mania compared with schizophrenia, stronger in bipolar euthymia than in bipolar mania. Psychotic features weakened the source LDAEP relative to nonpsychotic features. The severity of the depressive symptom was negatively correlated with source LDAEP. Conclusion These findings suggest that the serotonin activity of patients with bipolar disorder may vary according to mood status. A longitudinal follow-up study should be pursued using drug-naive subjects. PMID:22993531

  8. Estimation of cold plasma outflow during geomagnetic storms

    NASA Astrophysics Data System (ADS)

    Haaland, S.; Eriksson, A. I.; Andre, M.; Maes, L.; Baddeley, L. J.; Barakat, A. R.; Chappell, C. R.; Eccles, V.; Johnsen, C.; Lybekk, B.; Li, K.; Pedersen, A.; Schunk, R. W.; Welling, D. T.

    2015-12-01

    Low energy ions of ionospheric origin provide a significant contributon to the magnetospheric plasmapopulation. Measuring cold ions is difficult though. Observations have to be done at sufficiently high altitudes and typically in regions of space where spacecraft attain a positive charge due to solar illumination. Cold ions are therefore shielded from the satellite particle detectors. Furthermore, spacecraft can only cover key regions of ion outflow during segments of their orbit, so additional complications arise arise if continuous longtime observations such as the during a geomagnetic storms are needed. In this paper we suggest a new approach, based on a combination of synoptic observations and a novel technique to estimate the flux and total outflow during the various phases of geomagnetic storms. Our results indicate large variations in both outflow rates and transport throughout the storm. Prior to the storm main phase, outflow rates are moderate, and the cold ions are mainly emanating from moderately sized polar cap regions. Throughout the main phase of the storm, outflow rates increase and the polar cap source regions expand. Furthermore, faster transport, resulting from enhanced convection, leads to a much larger supply of cold ions to the near Earth region during gemagnetic storms.

  9. Estimation of cold plasma outflow during geomagnetic storms

    NASA Astrophysics Data System (ADS)

    Haaland, S.; Eriksson, A.; André, M.; Maes, L.; Baddeley, L.; Barakat, A.; Chappell, R.; Eccles, V.; Johnsen, C.; Lybekk, B.; Li, K.; Pedersen, A.; Schunk, R.; Welling, D.

    2015-12-01

    Low-energy ions of ionospheric origin constitute a significant contributor to the magnetospheric plasma population. Measuring cold ions is difficult though. Observations have to be done at sufficiently high altitudes and typically in regions of space where spacecraft attain a positive charge due to solar illumination. Cold ions are therefore shielded from the satellite particle detectors. Furthermore, spacecraft can only cover key regions of ion outflow during segments of their orbit, so additional complications arise if continuous longtime observations, such as during a geomagnetic storm, are needed. In this paper we suggest a new approach, based on a combination of synoptic observations and a novel technique to estimate the flux and total outflow during the various phases of geomagnetic storms. Our results indicate large variations in both outflow rates and transport throughout the storm. Prior to the storm main phase, outflow rates are moderate, and the cold ions are mainly emanating from moderately sized polar cap regions. Throughout the main phase of the storm, outflow rates increase and the polar cap source regions expand. Furthermore, faster transport, resulting from enhanced convection, leads to a much larger supply of cold ions to the near-Earth region during geomagnetic storms.

  10. Bipolar battery construction

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

    1981-01-01

    A lightweight, bipolar battery construction for lead acid batteries in which a plurality of thin, rigid, biplates each comprise a graphite fiber thermoplastic composition in conductive relation to lead stripes plated on opposite flat surfaces of the plates, and wherein a plurality of nonconductive thermoplastic separator plates support resilient yieldable porous glass mats in which active material is carried, the biplates and separator plates with active material being contained and maintained in stacked assembly by axial compression of the stacked assembly. A method of assembling such a bipolar battery construction.

  11. Dominant Nuclear Outflow Driving Mechanisms in Powerful Radio Galaxies

    NASA Astrophysics Data System (ADS)

    Batcheldor, Dan; Tadhunter, Clive; Holt, Joanna; Morganti, Raffaella; O'Dea, Christopher P.; Axon, David J.; Koekemoer, Anton

    2007-05-01

    In order to identify the dominant nuclear outflow mechanisms in active galactic nuclei, we have undertaken deep, high-resolution observations of two compact radio sources (PKS 1549-79 and PKS 1345+12) with the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope. Not only are these targets known to have powerful emission-line outflows, but they also contain all the potential drivers for the outflows: relativistic jets, quasar nuclei, and starbursts. ACS allows the compact nature (<0.15") of these radio sources to be optically resolved for the first time. Through comparison with existing radio maps, we have seen consistency in the nuclear position angles of both the optical emission-line and radio data. There is no evidence for biconical emission-line features on the large scale, and there is a divergence in the relative position angles of the optical and radio structure. This enables us to exclude starburst-driven outflows. However, we are unable to clearly distinguish between radiative AGN wind-driven outflows and outflows powered by relativistic radio jets. The small-scale biconical features, indicative of such mechanisms, could be below the resolution limit of ACS, especially if aligned close to the line of sight. In addition, there may be offsets between the radio and optical nuclei induced by heavy dust obscuration, nebular continuum, or scattered light from the AGN. Based on observations made with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555. These observations are associated with program 10206.

  12. Endophenotypes in bipolar disorder.

    PubMed

    Lenox, Robert H; Gould, Todd D; Manji, Husseini K

    2002-05-01

    The search for genes in bipolar disorder has provided numerous genetic loci that have been linked to susceptibility to developing the disorder. However, because of the genetic heterogeneity inherent in bipolar disorder, additional strategies may need to be employed to fully dissect the genetic underpinnings. One such strategy involves reducing complex behaviors into their component parts (endophenotypes). Abnormal neurophysiological, biochemical, endocrinological, neuroanatomical, cognitive, and neuropsychological findings are characteristics that often accompany psychiatric illness. It is possible that some of these may eventually be useful in subdefining complex genetic disorders, allowing for improvements in diagnostic assessment, genetic linkage studies, and development of animal models. Findings in patients with bipolar disorder that may eventually be useful as endophenotypes include abnormal regulation of circadian rhythms (the sleep/wake cycle, hormonal rhythms, etc.), response to sleep deprivation, P300 event-related potentials, behavioral responses to psychostimulants and other medications, response to cholinergics, increase in white matter hyperintensities (WHIs), and biochemical observations in peripheral mononuclear cells. Targeting circadian rhythm abnormalities may be a particularly useful strategy because circadian cycles appear to be an inherent evolutionarily conserved function in all organisms and have been implicated in the pathophysiology of bipolar disorder. Furthermore, lithium has been shown to regulate circadian cycles in diverse species, including humans, possibly through inhibition of glycogen synthase kinase 3-beta (GSK-3beta), a known target of lithium. PMID:11992561

  13. NGC 6334-V - An infrared bipolar nebula

    NASA Technical Reports Server (NTRS)

    Harvey, P. M.; Wilking, B. A.

    1984-01-01

    High angular resolution infrared mapping of the enigmatic far-infrared source NGC 6334-V shows it to have a bipolar structure at 1-4 microns. This structure together with the near-infrared colors and previous observations of H2 emission suggests a model for the source (IRS 4) in which a single luminous star is embedded in a dust cloud with a disklike geometry. Photometry of near-infrared sources within 0.5 pc of IRS 4 is also presented. These data suggest that there are at least four lower luminosity members of a young, dense cluster associated with the dominant source.

  14. Interstitial thermotherapy with bipolar electrosurgical devices

    NASA Astrophysics Data System (ADS)

    Desinger, Kai; Stein, Thomas; Boehme, A.; Mack, Martin G.; Mueller, Gerhard J.

    1998-01-01

    In addition to the laser, microwave or other energy sources, interstitial thermotherapy with radio-frequency current (RFITT) in bipolar technique has already been shown in vitro to be a safe and economical alternative energy source with a comparable operating performance. The bipolar technique is, from the technical point of view, completely without risk whereas with monopolar devices, where a neutral electrode has to be applied, an uncontrolled current flow passes through the patient's body. The therapeutical application efficiency of these bipolar RF-needle applicators was evaluated using newly designed high performance flushed and cooled probes (qq 3 mm). These can be used to create large coagulation volumes in tissue such as for the palliative treatment of liver metastases or the therapy of the benign prostate hyperplasia. As a result, the achievable lesion size resulting from these flushed and internally cooled RF- probes could be increased by a factor of three compared to a standard bipolar probe. With these bipolar power RF- applicators, coagulation dimensions of 5 cm length and 4 cm diameter with a power input of 40 watt could be achieved within 20 minutes. No carbonization and electrode tissue adherence was found. Investigations in vitro with adapted RFITT-probes using paramagnetic materials such as titanium alloys and high performance plastic have shown that monitoring under MRI (Siemens Magnetom, 1.5 Tesla), allows visualization of the development of the spatial temperature distribution in tissue using an intermittent diagnostic and therapeutical application. This does not lead to a loss in performance compared to continuous application. A ratio of 1:4 (15 s Thermo Flash MRI, 60 s RF-energy) has shown to be feasible.

  15. Nitrided Metallic Bipolar Plates

    SciTech Connect

    Brady, Michael P; Tortorelli, Peter F; Pihl, Josh A; Toops, Todd J; More, Karren Leslie; Meyer III, Harry M; Vitek, John Michael; Wang, Heli; Turner, John; Wilson, Mahlon; Garzon, Fernando; Rockward, Tommy; Connors, Dan; Rakowski, Jim; Gervasio, Don

    2008-01-01

    The objectives are: (1) Develop and optimize stainless steel alloys amenable to formation of a protective Cr-nitride surface by gas nitridation, at a sufficiently low cost to meet DOE targets and with sufficient ductility to permit manufacture by stamping. (2) Demonstrate capability of nitridation to yield high-quality stainless steel bipolar plates from thin stamped alloy foils (no significant stamped foil warping or embrittlement). (3) Demonstrate single-cell fuel cell performance of stamped and nitrided alloy foils equivalent to that of machined graphite plates of the same flow-field design ({approx}750-1,000 h, cyclic conditions, to include quantification of metal ion contamination of the membrane electrode assembly [MEA] and contact resistance increase attributable to the bipolar plates). (4) Demonstrate potential for adoption in automotive fuel cell stacks. Thin stamped metallic bipolar plates offer the potential for (1) significantly lower cost than currently-used machined graphite bipolar plates, (2) reduced weight/volume, and (3) better performance and amenability to high volume manufacture than developmental polymer/carbon fiber and graphite composite bipolar plates. However, most metals exhibit inadequate corrosion resistance in proton exchange membrane fuel cell (PEMFC) environments. This behavior leads to high electrical resistance due to the formation of surface oxides and/or contamination of the MEA by metallic ions, both of which can significantly degrade fuel cell performance. Metal nitrides offer electrical conductivities up to an order of magnitude greater than that of graphite and are highly corrosion resistant. Unfortunately, most conventional coating methods (for metal nitrides) are too expensive for PEMFC stack commercialization or tend to leave pinhole defects, which result in accelerated local corrosion and unacceptable performance.

  16. Martian groundwater outflow processes and morphology; reconstruction of paleohydrology using landscape evolution experiments

    NASA Astrophysics Data System (ADS)

    Marra, Wouter A.; Kleinhans, Maarten G.; de Jong, Steven M.; Hauber, Ernst

    2015-04-01

    Groundwater played an important role in the aqueous history of Mars but how, how long, and with what intensity remains unclear. Two types of fluvial landforms related to groundwater emergence are the giant outflow channels and the disputed sapping valleys. Understanding of the relation between subsurface and surface processes is slim, which limits inferences of climate implications from the observable morphology. We aim to increase this understanding and to apply this knowledge to Martian cases to reconstruct former hydrological conditions. Using a series of sandbox experiments, we investigated formative processes of valleys formed by groundwater. These experiments showed the morphology and processes of groundwater sapping and pressurized groundwater outflow (see Marra et al, 2014, Icarus doi:10.1016/j.icarus.2013.12.026) and further focused on landscape characteristics of groundwater sapping sourced locally or distally, and identified various processes linked to pressurized groundwater outbursts including the formation and eruption of subsurface reservoirs that can explain the high reconstructed discharges of large outflow valleys (see Marra et al, 2014, JGR doi:10.1002/2014JE004701). Based on the experiments, we identified novel morphological indicators for groundwater outflow in the outflow channel region of Lunae and Ophir Plana. These, in combination with the classic outflow features, show a clear trend of increasing outflow magnitude with decreasing elevation to the northeast, indicating a head from a common aquifer. The putative aquifer we identified was likely recharged by infiltration over the Tharsis region. Outflow channel activity peaked in the Hesperian, but continued in the Amazonian at a lower magnitude. Our results agree well with groundwater recharge in the Noachian and Early Hesperian, corresponding to a climate that sustained an active hydrological cycle. Furthermore, the large outflow events require a confining layer to build up enough pressure

  17. APEX-CHAMP+ high-J CO observations of low-mass young stellar objects. III. NGC 1333 IRAS 4A/4B envelope, outflow, and ultraviolet heating

    NASA Astrophysics Data System (ADS)

    Yıldız, Umut A.; Kristensen, Lars E.; van Dishoeck, Ewine F.; Belloche, Arnaud; van Kempen, Tim A.; Hogerheijde, Michiel R.; Güsten, Rolf; van der Marel, Nienke

    2012-06-01

    Context. The NGC 1333 IRAS 4A and IRAS 4B sources are among the most well-studied Stage 0 low-mass protostars, which drive prominent bipolar outflows. Spectrally resolved molecular emission lines provide crucial information about the physical and chemical structure of the circumstellar material as well as the dynamics of the different components. Most studies have so far concentrated on the colder parts (T ≤ 30 K) of these regions. Aims: The aim is to characterize the warmer parts of the protostellar envelope using the new generation of submillimeter instruments. This will allow us to quantify the feedback of the protostars on their surroundings in terms of shocks, ultraviolet (UV) heating, photodissociation, and outflow dispersal. Methods: The dual frequency 2 × 7 pixel 650/850 GHz array receiver CHAMP+ mounted on APEX was used to obtain a fully sampled, large-scale ~4' × 4' map at 9″ resolution of the IRAS 4A/4B region in the 12CO J = 6-5 line. Smaller maps were observed in the 13CO 6-5 and [C i] J = 2-1 lines. In addition, a fully sampled 12CO J = 3-2 map made with HARP-B on the JCMT is presented and deep isotopolog observations are obtained at selected outflow positions to constrain the optical depth. Complementary Herschel-HIFI and ground-based lines of CO and its isotopologs, from J = 1-0 up to 10-9 (Eu/k ≈ 300 K), are collected at the source positions and used to construct velocity-resolved CO ladders and rotational diagrams. Radiative-transfer models of the dust and lines are used to determine the temperatures and masses of the outflowing and photon-heated gas and infer the CO abundance structure. Results: Broad CO emission-line profiles trace entrained shocked gas along the outflow walls, which have an average temperature of ~100 K. At other positions surrounding the outflow and the protostar, the 6-5 line profiles are narrow indicating UV excitation. The narrow 13CO 6-5 data directly reveal the UV heated gas distribution for the first time. The

  18. MOLECULAR OUTFLOWS IN THE SUBSTELLAR DOMAIN: MILLIMETER OBSERVATIONS OF YOUNG VERY LOW MASS OBJECTS IN TAURUS AND {rho} OPHIUCHI

    SciTech Connect

    Ngoc Phan-Bao; Lee, Chin-Fei; Ho, Paul T. P.; Tang, Ya-Wen E-mail: pbngoc@asiaa.sinica.edu.tw

    2011-07-01

    We report here our search for molecular outflows from young very low mass stars and brown dwarfs in Taurus and {rho} Ophiuchi. Using the Submillimeter Array and the Combined Array for Research in Millimeter-wave Astronomy, we have observed four targets at 1.3 mm wavelength (230 GHz) to search for CO J = 2 {yields} 1 outflows. A young very low mass star MHO 5 (in Taurus) with an estimated mass of 90 M{sub J}, which is just above the hydrogen-burning limit, shows two gas lobes that are likely outflows. While the CO map of MHO 5 does not show a clear structure of outflow, possibly due to environment gas, its position-velocity diagram indicates two distinct blue- and redshifted components. We therefore conclude that they are components of a bipolar molecular outflow from MHO 5. We estimate an outflow mass of 7.0 x 10{sup -5} M{sub sun} and a mass-loss rate of 9.0 x 10{sup -10} M{sub sun}. These values are over two orders of magnitude smaller than the typical ones for T Tauri stars and somewhat weaker than those we have observed in the young brown dwarf ISO-Oph 102 of 60 M{sub J} in {rho} Ophiuchi. This makes MHO 5 the first young very low mass star showing a bipolar molecular outflow in Taurus. The detection boosts the scenario that very low mass objects form like low-mass stars but in a version scaled down by a factor of over 100.

  19. A SYSTEMATIC SEARCH FOR MOLECULAR OUTFLOWS TOWARD CANDIDATE LOW-LUMINOSITY PROTOSTARS AND VERY LOW LUMINOSITY OBJECTS

    SciTech Connect

    Schwarz, Kamber R.; Shirley, Yancy L.; Dunham, Michael M.

    2012-10-01

    We present a systematic single-dish search for molecular outflows toward a sample of nine candidate low-luminosity protostars and 30 candidate very low luminosity objects (VeLLOs; L{sub int} {<=} 0.1 L{sub Sun }). The sources are identified using data from the Spitzer Space Telescope cataloged by Dunham et al. toward nearby (D < 400 pc) star-forming regions. Each object was observed in {sup 12}CO and {sup 13}CO J = 2 {yields} 1 simultaneously using the sideband separating ALMA Band-6 prototype receiver on the Heinrich Hertz Telescope at 30'' resolution. Using five-point grid maps, we identify five new potential outflow candidates and make on-the-fly maps of the regions surrounding sources in the dense cores B59, L1148, L1228, and L1165. Of these new outflow candidates, only the map of B59 shows a candidate blue outflow lobe associated with a source in our survey. We also present larger and more sensitive maps of the previously detected L673-7 and the L1251-A-IRS4 outflows and analyze their properties in comparison to other outflows from VeLLOs. The accretion luminosities derived from the outflow properties of the VeLLOs with detected CO outflows are higher than the observed internal luminosity of the protostars, indicating that these sources likely had higher accretion rates in the past. The known L1251-A-IRS3 outflow is detected but not re-mapped. We do not detect clear, unconfused signatures of red and blue molecular wings toward the other 31 sources in the survey indicating that large-scale, distinct outflows are rare toward this sample of candidate protostars. Several potential outflows are confused with the kinematic structure in the surrounding core and cloud. Interferometric imaging is needed to disentangle large-scale molecular cloud kinematics from these potentially weak protostellar outflows.

  20. ALMA Observation of the 658 GHz Vibrationally Excited H2O Maser in Orion KL Source I

    NASA Astrophysics Data System (ADS)

    Hirota, Tomoya; Kim, Mi Kyoung; Honma, Mareki

    2016-02-01

    We present an observational study of the vibrationally excited H2O line at 658 GHz ({ν }2 = 1, {1}{1,0}-1{}{0,1}) toward Orion KL using the Atacama Large Millimeter/Submillimeter Array (ALMA). This line is clearly detected at the position of the massive protostar candidate, Source I. The spatial structure is compact, with a size of about 100 AU, and is elongated along the northeast-southwest low-velocity (18 km -1) bipolar outflow traced by 22 GHz H2O masers, SiO masers, and thermal SiO lines. A velocity gradient can be seen perpendicular to the bipolar outflow. The overall spatial and velocity structure seems to be analogous to that of the 321 GHz H2O maser line previously detected with ALMA and vibrationally excited SiO maser emission. The brightness temperature of the 658 GHz H2O line is estimated to be higher than 2 × 104 K, implying that it is emitted via maser action. Our results suggest that the 658 GHz H2O maser line is emitted from the base of the outflow from a rotating and expanding accretion disk as observed for the SiO masers and the 321 GHz H2O maser. We also search for two other H2O lines at 646 GHz (9{}{7,3}-8{}{8,0} and {9}{7,2}-8{}{8,1}), but they are not detected in Orion KL.

  1. Empirical outflow velocities in an equatorial coronal streamer

    NASA Astrophysics Data System (ADS)

    Strachan, L.; Suleiman, R.; Panasyuk, A.; Biesecker, D.; Kohl, J.

    We use combined Ultraviolet Coronagraph Spectrometer (UVCS) and Large Angle Spectroscopic Coronagraph (LASCO) data to determine the O5+ outflow velocities as a function of height along the axis of an equatorial streamer at solar minimum and as a function of latitude (at 2.3 solar radii from sun center). The results show that outflow increases rather abruptly in the region between 3.6 and 4.1 solar radii near the streamer cusp, and gradually increases to 90 km/s at about 5 solar radii in the streamer stalk beyond the cusp. The latitudinal variation at 2.3 solar radii shows that there is no outflow (within the measurement uncertainties) in the center of the streamer called the core, and that a steep increase in outflow occurs just beyond the streamer legs, where the O VI 1032 intensity relative to H I 1216 (Ly) is higher than in the core. Velocity variations in both height and latitude show that the transitions from no measurable outflow to positive outflow are relatively sharp and thus can be used to infer the location of the transition from closed to open field lines in streamer magnetic field topologies. Such information, including the densities and kinetic temperatures derived from the observations, provides hard constraints for realistic theoretical models of streamers and the source regions of the slow solar wind. This work is supported by NASA Grant NAG5-11420 to the Smithsonian Astrophysical Observatory, by the Italian Space Agency, and by the ESA PRODEX program (Swiss contribution).

  2. RADIATION TRANSFER OF MODELS OF MASSIVE STAR FORMATION. II. EFFECTS OF THE OUTFLOW

    SciTech Connect

    Zhang, Yichen; Tan, Jonathan C.; McKee, Christopher F. E-mail: jt@astro.ufl.edu

    2013-04-01

    We present radiation transfer simulations of a massive (8 M{sub Sun }) protostar forming from a massive (M{sub c} = 60 M{sub Sun }) protostellar core, extending the model developed by Zhang and Tan. The two principal improvements are (1) developing a model for the density and velocity structure of a disk wind that fills the bipolar outflow cavities, based in part on the disk-wind model of Blandford and Payne; and (2) solving for the radially varying accretion rate in the disk due to a supply of mass and angular momentum from the infall envelope and their loss to the disk wind. One consequence of the launching of the disk wind is a reduction in the amount of accretion power that is radiated by the disk. We also include a non-Keplerian potential appropriate for a growing, massive disk. For the transition from dusty to dust-free conditions where gas opacities dominate, we now implement a gradual change as a more realistic approximation of dust destruction. We study how the above effects, especially the outflow, influence the spectral energy distributions (SEDs) and the synthetic images of the protostar. Dust in the outflow cavity significantly affects the SEDs at most viewing angles. It further attenuates the short-wavelength flux from the protostar, controlling how the accretion disk may be viewed, and contributes a significant part of the near- and mid-IR fluxes. These fluxes warm the disk, boosting the mid- and far-IR emission. We find that for near face-on views, i.e., looking down the outflow cavity (although not too close to the axis), the SED from the near-IR to about 60 {mu}m is very flat, which may be used to identify such systems. We show that the near-facing outflow cavity and its walls are still the most significant features in images up to 70 {mu}m, dominating the mid-IR emission and determining its morphology. The thermal emission from the dusty outflow itself dominates the flux at {approx}20 {mu}m. The detailed distribution of the dust in the outflow

  3. Hydrothermal outflow plume of Valles caldera, New Mexico, and a comparison with other outflow plumes

    SciTech Connect

    Goff, F.; Shevenell, L.; Gardner, J.N.; Vuataz, F.; Grigsby, C.O.

    1988-06-10

    Stratigraphic, temperature gradient, hydrogeochemical, and hydrologic data have been integrated with geologic data from previous studies to show the structural configuration of the Valles caldera hydrothermal outflow plume. Hydrologic data suggest that 25--50% of the discharge of the Valles outflow is confined to the Jemez fault zone, which predates caldera formation. Thermal gradient data from bores penetrating the plume show that shallow gradients are highest in the vicinity of the Jemez fault zone (up to 190 /sup 0/C/km). Shallow heat flow above the hydrothermal plume is as high as 500 mW m/sup -2/ near core hole VC-1 (Jemez fault zone) to 200 mW m/sup -2/ at Fenton Hill (Jemez Plateau). Chemical and isotopic data indicate that two source reservoirs within the caldera (Redondo Creek and Sulphur Springs reservoirs) are parents to mixed fluids flowing in the hydrothermal plume. However, isotopic data, borehole data, basic geology, and inverse relations between temperature and chloride content at major hot springs indicate that no single reservoir fluid and no single diluting fluid are involved in mixing. The Valles caldera hydrothermal plume is structurally dominated by lateral flow through a belt of vertical conduits (Jemez fault zone) that strike away from the source reservoir. Stratigraphically confined flow is present but dispersed over a wide area in relatively impermeable rocks. The Valles configuration is contrasted with the configuration of the hydrothermal plume at Roosevelt Hot Springs, which is dominated by lateral flow through a near-surface, widespread, permeable aquifer. Data from 12 other representative geothermal systems show that outflow plumes occur in a variety of magmatic and tectonic settings, have varying reservoir compositions, and have different flow characteristics.

  4. An Unbiased Search for Molecular Hydrogen Outflows in the Orion B Star Forming Region

    NASA Astrophysics Data System (ADS)

    Froebrich, D.; Ziener, R.; Eislöffel, J.

    The formation of stars is often accompanied by molecular outflows. One possible tracer of these outflows is the shocked emission of molecular hydrogen in the near-infrared. We conducted an unbiased survey for molecular outflows in the Orion B region with MAGIC at the 1.23 m telescope on Calar Alto in the 1-0 S(1) line of molecular hydrogen at 2.212μm and in the K' bandpass (continuum). The observed field was about 2.7 square degrees, including the known outflows of NGC2071, HH19, HH24, HH25, HH26, HH27, HH37, HH67, HH91, HH92, HH93, HH94, HH212, HH247, HH248, HH249 and HH260. In addition to these known H2 flows, we find ten new groups of H2 emission features, and discuss their morphology and possible outflow sources.

  5. Accretion Disk Outflows from Compact Object Mergers

    NASA Astrophysics Data System (ADS)

    Metzger, Brian

    nuclear reaction network along characteristic Lagrangian trajectories. Results of these calculations will be used to (1) reassess NS-NS/NS-BH mergers as an astrophysical source of heavy r-process nuclei; and (2) calculate the light curves of the optical transients (`kilonovae') powered by the radioactive decay. Separate work will assess the effects that neutrino irradiation from a long-lived neutron star remnant has on the electron fraction of the disk outflows. The strong contrast between the opacities of proton- and neutron-rich matter imply that the presence and lifetime of such a remnant could be imprinted on the kilonova emission. Our investigation sheds light on the central engines of GRBs and other high-energy transients and hence is relevant to NASA's Swift, MAXI, and Fermi missions. Our results will also impact the interpretation of future observations of supernovae and their galactic environments with the Hubble Space Telescope (HST). Our results will also impact follow-up observations of kilonovae, maximizing the impact of HST to constrain the key open questions such as the progenitors of gamma-ray bursts and the origin of r-process nuclei.

  6. BIPOLAR JETS LAUNCHED FROM ACCRETION DISKS. II. THE FORMATION OF ASYMMETRIC JETS AND COUNTER JETS

    SciTech Connect

    Fendt, Christian; Sheikhnezami, Somayeh E-mail: nezami@mpia.de

    2013-09-01

    We investigate the jet launching from accretion disks, in particular the formation of intrinsically asymmetric jet/counter jet systems. We perform axisymmetric MHD simulations of the disk-jet structure on a bipolar computational domain covering both hemispheres. We apply various models such as asymmetric disks with (initially) different scale heights in each hemisphere, symmetric disks into which a local disturbance is injected, and jets launched into an asymmetric disk corona. We consider both a standard global magnetic diffusivity distribution and a novel local diffusivity model. Typical disk evolution first shows substantial disk warping and then results in asymmetric outflows with a 10%-30% mass flux difference. We find that the magnetic diffusivity profile is essential for establishing a long-term outflow asymmetry. We conclude that bipolar asymmetry in protostellar and extragalactic jets can indeed be generated intrinsically and maintained over a long time by disk asymmetries and the standard jet launching mechanism.

  7. ISOTROPICALLY DRIVEN VERSUS OUTFLOW DRIVEN TURBULENCE: OBSERVATIONAL CONSEQUENCES FOR MOLECULAR CLOUDS

    SciTech Connect

    Carroll, Jonathan J.; Frank, Adam; Blackman, Eric G.

    2010-10-10

    Feedback from protostellar outflows can influence the nature of turbulence in star-forming regions even if they are not the primary source of velocity dispersion for all scales of molecular clouds. For the rate and power expected in star-forming regions, we previously (Carroll et al.) demonstrated that outflows could drive supersonic turbulence at levels consistent with the scaling relations from Matzner although with a steeper velocity power spectrum than expected for an isotropically driven supersonic turbulent cascade. Here, we perform higher resolution simulations and combine simulations of outflow driven turbulence with those of isotropically forced turbulence. We find that the presence of outflows within an ambient isotropically driven turbulent environment produces a knee in the velocity power spectrum at the outflow scale and a steeper slope at sub-outflow scales than for a purely isotropically forced case. We also find that the presence of outflows flattens the density spectrum at large scales effectively reducing the formation of large-scale turbulent density structures. These effects are qualitatively independent of resolution. We have also carried out Principal Component Analysis (PCA) for synthetic data from our simulations. We find that PCA as a tool for identifying the driving scale of turbulence has a misleading bias toward low amplitude large-scale velocity structures even when they are not necessarily the dominant energy containing scales. This bias is absent for isotropically forced turbulence but manifests strongly for collimated outflow driven turbulence.

  8. MASSIVE MOLECULAR OUTFLOWS AND NEGATIVE FEEDBACK IN ULIRGs OBSERVED BY HERSCHEL-PACS

    SciTech Connect

    Sturm, E.; Gracia-Carpio, J.; Hailey-Dunsheath, S.; Contursi, A.; Poglitsch, A.; Davies, R.; Genzel, R.; Lutz, D.; Tacconi, L.; De Jong, J. A.; Gonzalez-Alfonso, E.; Veilleux, S.; Fischer, J.; Sternberg, A.; Verma, A.; Maiolino, R.

    2011-05-20

    Mass outflows driven by stars and active galactic nuclei (AGNs) are a key element in many current models of galaxy evolution. They may produce the observed black-hole-galaxy mass relation and regulate and quench both star formation in the host galaxy and black hole accretion. However, observational evidence of such feedback processes through outflows of the bulk of the star-forming molecular gas is still scarce. Here we report the detection of massive molecular outflows, traced by the hydroxyl molecule (OH), in far-infrared spectra of ULIRGs obtained with Herschel-PACS as part of the SHINING key project. In some of these objects the (terminal) outflow velocities exceed 1000 km s{sup -1}, and their outflow rates (up to {approx}1200 M{sub sun} yr{sup -1}) are several times larger than their star formation rates. We compare the outflow signatures in different types of ULIRGs and in starburst galaxies to address the issue of the energy source (AGN or starburst) of these outflows. We report preliminary evidence that ULIRGs with a higher AGN luminosity (and higher AGN contribution to L{sub IR}) have higher terminal velocities and shorter gas depletion timescales. The outflows in the observed ULIRGs are able to expel the cold gas reservoirs from the centers of these objects within {approx}10{sup 6}-10{sup 8} years.

  9. Pleated metal bipolar assembly

    DOEpatents

    Wilson, Mahlon S.; Zawodzinski, Christine

    2001-01-01

    A thin low-cost bipolar plate for an electrochemical cell is formed from a polymer support plate with first flow channels on a first side of the support plate and second flow channels on a second side of the support plate, where the first flow channels and second flow channels have intersecting locations and have a depth effective to form openings through the support plate at the intersecting locations. A first foil of electrically conductive material is pressed into the first flow channels. A second foil of electrically conductive material pressed into the second flow channels so that electrical contact is made between the first and second foils at the openings through the support plate. A particular application of the bipolar plate is in polymer electrolyte fuel cells.

  10. Carbamazepine in Bipolar Disorder With Pain: Reviewing Treatment Guidelines

    PubMed Central

    Campbell, Austin; O’Connell, Christopher R.; Nallapula, Kishan

    2014-01-01

    Objective: To determine if any monotherapy drug treatment has robust efficacy to treat comorbid bipolar disorder and chronic pain. Data Sources: The American Psychiatric Association (APA) treatment guidelines for bipolar mood disorder and the 2012 Cochrane database for pain disorders. Study Selection: We relied on the treatment guides to determine if the drugs that are APA guideline–supported to treat bipolar disorder have supporting data from the Cochrane database for chronic pain. Data Synthesis: No single drug was mentioned by either guideline to treat this comorbidity. However, carbamazepine was the only drug that has guideline-supported robust efficacy in the management of each condition separately. Conclusions: Carbamazepine was found to have strong preclinical data for the treatment of comorbid bipolar mood disorder and chronic pain disorders. While requiring more studies in this population, we propose that this treatment modality may benefit patients. PMID:25667814

  11. The ionospheric outflow feedback loop

    NASA Astrophysics Data System (ADS)

    Moore, T. E.; Fok, M.-C.; Garcia-Sage, K.

    2014-08-01

    Following a long period of observation and investigation beginning in the early 1970s, it has been firmly established that Earth's magnetosphere is defined as much by the geogenic plasma within it as by the geomagnetic field. This plasma is not confined to the ionosphere proper, defined as the region within a few density scale heights of the F-region plasma density peak. Rather, it fills the flux tubes on which it is created, and circulates throughout the magnetosphere in a pattern driven by solar wind plasma that becomes magnetically connected to the ionosphere by reconnection through the dayside magnetopause. Under certain solar wind conditions, plasma and field energy is stored in the magnetotail rather than being smoothly recirculated back to the dayside. Its release into the downstream solar wind is produced by magnetotail disconnection of stored plasma and fields both continuously and in the form of discrete plasmoids, with associated generation of energetic Earthward-moving bursty bulk flows and injection fronts. A new generation of global circulation models is showing us that outflowing ionospheric plasmas, especially O+, load the system in a different way than the resistive F-region load of currents dissipating energy in the plasma and atmospheric neutral gas. The extended ionospheric load is reactive to the primary dissipation, forming a time-delayed feedback loop within the system. That sets up or intensifies bursty transient behaviors that would be weaker or absent if the ionosphere did not “strike back” when stimulated. Understanding this response appears to be a necessary, if not sufficient, condition for us to gain accurate predictive capability for space weather. However, full predictive understanding of outflow and incorporation into global simulations requires a clear observational and theoretical identification of the causal mechanisms of the outflows. This remains elusive and requires a dedicated mission effort.

  12. Bipolar Disorder in Children and Teens

    MedlinePlus

    ... is in crisis. What do I do? Share Bipolar Disorder in Children and Teens Download PDF Download ePub ... brochure will give you more information. What is bipolar disorder? Bipolar disorder is a serious brain illness. It ...

  13. [Antipsychotics in bipolar disorders].

    PubMed

    Vacheron-Trystram, M-N; Braitman, A; Cheref, S; Auffray, L

    2004-01-01

    This article is a review of the various treatments that are currently available, in particular in France, for the treatment of bipolar disorders. This article specifically addresses the use of novel antipsychotic agents as alternative therapy to a lithium therapy and/or the use of conventional antipsychotics. The prevalence of bipolar disorder over a lifetime is around 1% of the general population. Bipolar disorder consists of alternating depressive and manic episodes. It mainly affects younger subjects, and is often associated with alcohol and drug addictions. There are two main subtypes of bipolar disorder. According to the DSM IV-R, type 1 of bipolar disorder is characterised when at least one manic episode (or a mixed episode) has been diagnosed. Type 2 of bipolar disorder is related to patients enduring recurrent depressive episodes but no manic episode. Type 2 affects women more frequently as opposed to type 1 affecting individuals of both sexes. Manic-depressive disorder (or cyclo-thymic disorder) appears in relation to patients who has never suffered manic episode, mixed episode or severe depressive episode but have undergone numerous periods with some symptoms of depression and hypomanic symptoms over a two-year period during which any asymptomatic periods last no longer than two months. The average age of the person going through a first episode (often a depressive one) is 20 years-old. Untreated bipolar patients may endure more than ten manic or depressive episodes. Finally, in relation to 10 to 20% of patients, the bipolar disorder will turn into a fast cycle form, either spontaneously or as a result of certain medical treatments. Psychiatrists are now able to initiate various treating strategies which are most likely to be effective as a result of the identification of clinical subtypes of the bipolar disorder. Lithium therapy has been effectively and acutely used for patients with pure or elated mania and its prophylaxis. However, lithium medication

  14. Atmospheric transport and outflow of polycyclic aromatic hydrocarbons from China.

    PubMed

    Lang, Chang; Tao, Shu; Liu, Wenxin; Zhang, Yanxu; Simonich, Staci

    2008-07-15

    A potential receptor influence function (PRIF) model, based on air mass forward trajectory calculations, was applied to simulate the atmospheric transport and outflow of polycyclic aromatic hydrocarbons (PAHs) emitted from China. With a 10 day atmospheric transport time, most neighboring countries and regions, as well as remote regions, were influenced by PAH emissions from China. Of the total annual PAH emission of 114 Gg, 92.7% remained within the boundary of mainland China. The geographic distribution of PRIFs within China was similar to the geographic distribution of the source regions, with high values in the North China Plain, Sichuan Basin, Shanxi, and Guizhou province. The Tarim basin and Sichuan basin had unfavorable meteorological conditions for PAH outflow. Of the PAH outflow from China (8092 tons or 7.1% of the total annual PAH emission), approximately 69.9% (5655 tons) reached no further than the offshore environment of mainland China and the South China Sea. Approximate 227, 71, 746, and 131 tons PAHs reached North Korea, South Korea, Russia-Mongolia region, and Japan, respectively, 2-4 days after the emission. Only 1.4 tons PAHs reached North America after more than 9 days. Interannual variation in the eastward PAH outflow was positively correlated to cold episodes of El Niño/Southern Oscillation. However, trans-Pacific atmospheric transport of PAHs from China was correlated to Pacific North America index (PNA) which is associated with the strength and position of westerly winds. PMID:18754369

  15. Simulated O VI Doppler dimming measurements of coronal outflow velocities

    NASA Technical Reports Server (NTRS)

    Strachan, Leonard; Gardner, L. D.; Kohl, John L.

    1992-01-01

    The possibility of determining O(5+) outflow velocities by using a Doppler dimming analysis of the resonantly scattered intensities of O VI lambda 1031.9 and lambda 1037.6 is addressed. The technique is sensitive to outflow velocities, W, in the range W greater than 30 and less than 250 km/s and can be used for probing regions of the inner solar corona, where significant coronal heating and solar wind acceleration may be occurring. These velocity measurements, when combined with measurements of other plasma parameters (temperatures and densities of ions and electrons) can be used to estimate the energy and mass flux of O(5+). In particular, it may be possible to locate where the flow changes from subsonic to supersonic and to identify source regions for the high and low speed solar wind. The velocity diagnostic technique is discussed with emphasis placed on the requirements needed for accurate outflow velocity determinations. Model determinations of outflow velocities based on simulated Doppler observations are presented.

  16. Atmospheric transport and outflow of polycyclic aromatic hydrocarbons from China

    SciTech Connect

    Chang Lang; Shu Tao; Wenxin Liu; Yanxu Zhang; Staci Simonich

    2008-07-15

    A potential receptor influence function (PRIF) model, based on air mass forward trajectory calculations, was applied to simulate the atmospheric transport and outflow of polycyclic aromatic hydrocarbons (PAHs) emitted from China. With a 10 day atmospheric transport time, most neighboring countries and regions, as well as remote regions, were influenced by PAH emissions from China. Of the total annual PAH emission of 114 Gg, 92.7% remained within the boundary of mainland China. The geographic distribution of PRIFs within China was similar to the geographic distribution of the source regions, with high values in the North China Plain, Sichuan Basin, Shanxi, and Guizhou province. The Tarim basin and Sichuan basin had unfavorable meteorological conditions for PAH outflow. Of the PAH outflow from China (8092 tons or 7.1% of the total annual PAH emission), approximately 69.9% (5655 tons) reached no further than the offshore environment of mainland China and the South China Sea. Approximate 227, 71, 746, and 131 tons PAHs reached North Korea, South Korea, Russia-Mongolia region, and Japan, respectively, 2-4 days after the emission. Only 1.4 tons PAHs reached North America after more than 9 days. Interannual variation in the eastward PAH outflow was positively correlated to cold episodes of El Nino/Southern Oscillation. However, trans-Pacific atmospheric transport of PAHs from China was correlated to Pacific North America index (PNA) which is associated with the strength and position of westerly winds. 38 refs., 4 figs.

  17. First Direct Measurement of Acceleration in the Outflow of a Nova: U Scorpii (1999)

    NASA Astrophysics Data System (ADS)

    Lépine, Sébastien; Shara, Michael M.; Livio, Mario; Zurek, David

    1999-09-01

    We report the first direct measurement of acceleration in the outflow of a nova, U Sco, observed 5 days after the start of an outburst. Spectroscopic time series of the intense Hα emission line, obtained with the Space Telescope Imaging Spectrograph camera on board the Hubble Space Telescope, shows a bright emission component moving across the spectrum at a rate of +0.16+/-0.02 Å in 30 minutes. This is consistent with a clump of emitting material having a line-of-sight acceleration ar=+4.1+/-0.5 m s-2. The data suggest that this clump resides within a moderately collimated bipolar outflow. Due to projection effects, this implies an actual acceleration of the clump relative to the star of a>~+25 m s-2. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS5-26555.

  18. The cometary cavity created by an aligned streaming environment/collimated outflow interaction

    NASA Astrophysics Data System (ADS)

    López-Cámara, D.; Esquivel, A.; Cantó, J.; Raga, A. C.; Velázquez, P. F.; Rodríguez-González, A.

    2011-10-01

    We present a ``thin shell'' model of the interaction of a biconical outflow and a streaming environment (aligned with the direction of the flow), as well as numerical (axisymmetric) simulations of such an interaction. A similar situation, although in a more complex setup, takes place at the head of the cometary structure of Mira. Thus, for most of the numerical simulations we explore parameters consistent with the observed bipolar outflow from Mira. For these parameters, the interaction is non-radiative, so that a rather broad jet/streaming environment interaction region is formed. In spite of this, a reasonable agreement between the thin-shell analytic model and the numerical simulations is obtained.

  19. Are X-ray emitting coronae around supermassive black holes outflowing?

    SciTech Connect

    Liu, Teng; Wang, Jun-Xian; Yang, Huan; Zhu, Fei-Fan; Zhou, You-Yuan E-mail: jxw@ustc.edu.cn

    2014-03-10

    Hard X-ray emission in radio-quiet active galactic nuclei (AGNs) is believed to be produced via inverse Compton scattering by hot and compact coronae near the supermassive black hole. However, the origin and physical properties of the coronae, including geometry, kinematics, and dynamics, remain poorly known. In this work, taking [O IV] 25.89 μm emission line as an isotropic indicator of AGNs' intrinsic luminosity, we compare the intrinsic corona X-ray emission between Seyfert 1 and Compton-thin Seyfert 2 galaxies, which are viewed at different inclinations according to the unification scheme. We compile a sample of 130 Compton-thin Seyfert galaxies with both [O IV] 25.89 μm line luminosities measured with the Spitzer Infrared Spectrometer and X-ray spectra observed by XMM-Newton, Chandra, Suzaku, or Swift. Known radio-loud sources are excluded. We fit the X-ray spectra to obtain the absorption-corrected 2-10 keV continuum luminosities. We find that Seyfert 1 galaxies are intrinsically brighter in intrinsic 2-10 keV emission by a factor of 2.8{sub −0.4}{sup +0.5} (2.2{sub −0.3}{sup +0.9} in Swift Burst Alert Telescope 14-195 keV emission), compared with Compton-thin Seyfert 2 galaxies. The Seyfert 1 and Compton-thin Seyfert 2 galaxies follow a statistically identical correlation between the absorption-corrected 2-10 keV luminosity and the 14-195 keV luminosity, indicating that our absorption correction to the 2-10 keV flux is sufficient. The difference in X-ray emission between the two populations is thus unlikely to be due to X-ray absorption, and instead implies an intrinsic anisotropy in the corona X-ray emission. This striking anisotropy of X-ray emission can be explained by a bipolar outflowing corona with a bulk velocity of ∼0.3-0.5c. This would provide a natural link between the so-called coronae and weak jets in these systems. Other consequences of outflowing coronae are also discussed.

  20. Outflows in Sodium Excess Objects

    NASA Astrophysics Data System (ADS)

    Park, Jongwon; Jeong, Hyunjin; Yi, Sukyoung K.

    2015-08-01

    Van Dokkum and Conroy revisited the unexpectedly strong Na i lines at 8200 Å found in some giant elliptical galaxies and interpreted them as evidence for an unusually bottom-heavy initial mass function. Jeong et al. later found a large population of galaxies showing equally extraordinary Na D doublet absorption lines at 5900 Å (Na D excess objects: NEOs) and showed that their origins can be different for different types of galaxies. While a Na D excess seems to be related to the interstellar medium (ISM) in late-type galaxies, smooth-looking early-type NEOs show little or no dust extinction and hence no compelling signs of ISM contributions. To further test this finding, we measured the Doppler components in the Na D lines. We hypothesized that the ISM would have a better (albeit not definite) chance of showing a blueshift Doppler departure from the bulk of the stellar population due to outflow caused by either star formation or AGN activities. Many of the late-type NEOs clearly show blueshift in their Na D lines, which is consistent with the former interpretation that the Na D excess found in them is related to gas outflow caused by star formation. On the contrary, smooth-looking early-type NEOs do not show any notable Doppler components, which is also consistent with the interpretation of Jeong et al. that the Na D excess in early-type NEOs is likely not related to ISM activities but is purely stellar in origin.

  1. A HOT MOLECULAR CIRCUMSTELLAR DISK AROUND THE MASSIVE PROTOSTAR ORION SOURCE I

    SciTech Connect

    Hirota, Tomoya; Honma, Mareki; Kim, Mi Kyoung; Kurono, Yasutaka

    2014-02-20

    We report new Atacama Large Millimeter/Submillimeter Array (ALMA) observations of a circumstellar disk around Source I in Orion KL, an archetype of massive protostar candidates. We detected two ortho-H{sub 2}O lines at 321 GHz (10{sub 2,} {sub 9}-9{sub 3,} {sub 6}) and 336 GHz (ν{sub 2} = 1, 5{sub 2,} {sub 3}-6{sub 1,} {sub 6}) for the first time in Source I. The latter one is in a vibrationally excited state at the lower state energy of 2939 K, suggesting evidence of hot molecular gas close to Source I. The integrated intensity map of the 321 GHz line is elongated along the bipolar outflow while the 336 GHz line map is unresolved with a beam size of 0.''4. Both of these maps show velocity gradients perpendicular to the bipolar outflow. The velocity centroid map of the 321 GHz line implies a spatial and velocity structure similar to that of vibrationally excited SiO masers tracing the root of the outflow emanating from the disk surface. In contrast, the 336 GHz line is most likely emitting from the disk midplane with a diameter of 0.''2 (84 AU) as traced by radio continuum emission and a dark lane devoid of the vibrationally excited SiO maser emission. The observed velocity gradient and the spectral profile of the 336 GHz H{sub 2}O line can be reconciled with a model of an edge-on ring-like structure with an enclosed mass of >7 M{sub ☉} and an excitation temperature of >3000 K. The present results provide further evidence of a hot and neutral circumstellar disk rotating around Source I with a diameter of ∼100 AU scale.

  2. OUTFLOW, INFALL, AND PROTOSTARS IN THE STAR-FORMING CORE W3-SE

    SciTech Connect

    Zhu Lei; Zhao Junhui; Wright, M. C. H. E-mail: jzhao@cfa.harvard.edu

    2011-10-20

    We report new results on outflow and infall in the star-forming cores W3-SE SMA-1 and SMA-2 based on analysis of {approx}2.''5 resolution observations of the molecular lines HCN(3-2), HCO{sup +}(3-2), N{sub 2}H{sup +}(3-2), and CH{sub 3}OH(5{sub 2,3}-4{sub 1,3}) with the Submillimeter Array (SMA). A high-velocity bipolar outflow originating from the protostellar core SMA-1 was observed in the HCN(3-2) line, with a projected outflow axis at a position angle of 48{sup 0}. The detection of the outflow is confirmed from other molecular lines. An inverse P-Cygni profile in the HCN(3-2) line toward SMA-1 suggests that at least one of the double cores accretes matter from the molecular core. A filamentary structure in the molecular gas surrounds SMA-1 and SMA-2. Based on the SMA observations, our analysis suggests that the double pre-stellar cores SMA-1 and SMA-2 result from fragmentation in the collapsing massive molecular core W3-SE, and it is likely that they are forming intermediate- to high-mass stars which will be new members of a star cluster in the W3-SE region.

  3. Optical orientation in bipolar spintronic devices

    NASA Astrophysics Data System (ADS)

    Fabian, Jaroslav; Žutić, Igor

    2008-11-01

    Optical orientation is a highly efficient tool for the generation of nonequilibrium spin polarization in semiconductors. Combined with spin-polarized transport it offers new functionalities for conventional electronic devices, such as pn junction bipolar diodes or transistors. In nominally nonmagnetic junctions optical orientation can provide a source for spin capacitance—the bias-dependent nonequilibrium spin accumulation—or for spin-polarized current in bipolar spin-polarized solar cells. In magnetic junctions, the nonequilibrium spin polarization generated by spin orientation in the proximity of an equilibrium magnetization gives rise to the spin-voltaic effect (a realization of the Silsbee-Johnson coupling), enabling efficient control of electrical properties such as the I-V characteristics of the junctions by magnetic and optical fields. This paper reviews the main results of investigations of spin-polarized and magnetic pn junctions, from spin capacitance to the spin-voltaic effect.

  4. POST ASYMPTOTIC GIANT BRANCH BIPOLAR REFLECTION NEBULAE: RESULT OF DYNAMICAL EJECTION OR SELECTIVE ILLUMINATION?

    SciTech Connect

    Koning, N.; Kwok, Sun; Steffen, W. E-mail: sunkwok@hku.hk

    2013-03-10

    A model for post asymptotic giant branch bipolar reflection nebulae has been constructed based on a pair of evacuated cavities in a spherical dust envelope. Many of the observed features of bipolar nebulae, including filled bipolar lobes, an equatorial torus, searchlight beams, and a bright central light source, can be reproduced. The effects on orientation and dust densities are studied and comparisons with some observed examples are offered. We suggest that many observed properties of bipolar nebulae are the result of optical effects and any physical modeling of these nebulae has to take these factors into consideration.

  5. A numerical study of the Nordic Sea circulation and outflows

    NASA Astrophysics Data System (ADS)

    Yang, J.; Pratt, L. J.

    2010-12-01

    The Nordic Seas outflow over the Greenland-Iceland-Scotland Ridge is investigated by using a two-layer numerical model with both idealized and realistic topography. The study focuses on physical processes and topographic effects that influence the pathways of the Nordic Seas source water that feeds the overflow through the Denmark Strait and Faroe Bank Channel. The potential vorticity balance and integral constraints will be used to explain the sensitivity of the overflows to the upstream (Nordic Seas) circulation and forcing.

  6. The most powerful quasar outflows as revealed by the Civ λ1549 resonance line

    NASA Astrophysics Data System (ADS)

    Marziani, P.; Martínez Carballo, M. A.; Sulentic, J. W.; Del Olmo, A.; Stirpe, G. M.; Dultzin, D.

    2016-01-01

    Outflows from quasars may be almost ubiquitous, but there are significant differences on a source- by-source basis. These differences can be organized along the 4D Eigenvector 1 sequence: at low z, only the Population A sources radiating at relatively high Eddington ratio show evidences of prominent high- velocity outflows from the Civλ1549 line profiles. Here we discuss, starting from recent observations of high-luminosity sample of Hamburg-ESO quasars, the Civλ1549 emission line profiles and how they are affected by outflow motion as a function of the quasar luminosity. Our high-luminosity sample has the notable advantage that the rest frame has been set by previous Hβ observations in the J, H, and K band, therefore making measurements of inter-line shift accurate and free of systemic biases. As the redshift increases and the luminosity of the brightest quasars grows, powerful, high-velocity outflows may become more frequent. We then discuss the outflow contextualisation following the 4DE1 approach as a tool for unveiling the nature of the so-called Weak Lined Quasars (WLQs) that have emerged in recent years as a new, poorly understood class of quasars. We estimate the kinetic power associated with the Civλ1549 emitting gas in outflow, and we suggest that the host galaxies of the most luminous sources may experience a significant feedback effect.

  7. In situ doping control for growth of n p n Si/SiGe/Si heterojunction bipolar transistor by gas source molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Gao, F.; Huang, D. D.; Li, J. P.; Liu, C.

    2005-01-01

    N-p-n Si/SiGe/Si heterostructures have been grown by a disilane (Si 2H 6) gas and Ge solid sources molecular beam epitaxy system using phosphine (PH 3) and diborane (B 2H 6) as n- and p-type in situ doping sources, respectively. Adopting an in situ doping control technology, the influence of background B dopant on the growth of n-Si emitter layer was reduced, and an abrupt B dopant distribution from SiGe base to Si emitter layer was obtained. Besides, higher n-type doping in the surface region of emitter to reduce the emitter resist can be realized, and it did not result in the drop of growth rate of Si emitter layer in this technology.

  8. 33 CFR Appendix A to Part 157 - Damage Assumptions, Hypothetical Outflows, and Cargo Tank Size and Arrangements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Damage Assumptions, Hypothetical Outflows, and Cargo Tank Size and Arrangements A Appendix A to Part 157 Navigation and Navigable Waters...—Damage Assumptions, Hypothetical Outflows, and Cargo Tank Size and Arrangements 1. Source. The...

  9. An Iron K Component to the Ultrafast Outflow in NGC 1313 X-1

    NASA Astrophysics Data System (ADS)

    Walton, D. J.; Middleton, M. J.; Pinto, C.; Fabian, A. C.; Bachetti, M.; Barret, D.; Brightman, M.; Fuerst, F.; Harrison, F. A.; Miller, J. M.; Stern, D.

    2016-08-01

    We present the detection of an absorption feature at E={8.77}-0.06+0.05 keV in the combined X-ray spectrum of the ultraluminous X-ray source NGC 1313 X-1 observed with XMM-Newton and NuSTAR, significant at the 3σ level. If associated with blueshifted ionized iron, the implied outflow velocity is ˜0.2c for Fe xxvi, or ˜0.25c for Fe xxv. These velocities are similar to the ultrafast outflow seen in absorption recently discovered in this source at lower energies by XMM-Newton, and we therefore conclude that this is an iron component to the same outflow. Photoionization modeling marginally prefers the Fe xxv solution, but in either case the outflow properties appear to be extreme, potentially supporting a super-Eddington hypothesis for NGC 1313 X-1.

  10. New electroplated aluminum bipolar plate for PEM fuel cell

    NASA Astrophysics Data System (ADS)

    El-Enin, Sanaa A. Abo; Abdel-Salam, Omar E.; El-Abd, Hammam; Amin, Ashraf M.

    Further improvement in the performance of the polymer electrolyte membrane fuel cells as a power source for automotive applications may be achieved by the use of a new material in the manufacture of the bipolar plate. Several nickel alloys were applied on the aluminum substrate, the use of aluminum as a bipolar plate instead of graphite is to reduce the bipolar plate cost and weight and the ease of machining. The electroplated nickel alloys on aluminum substrate produced a new metallic bipolar plate for PEM fuel cell with a higher efficiency and longer lifetime than the graphite bipolar plate due to its higher electrical conductivity and its lower corrosion rate. Different pretreatment methods were tested; the optimum method for pretreatment consists of dipping the specimen in a 12.5% NaOH for 3 min followed by electroless zinc plating for 2 min, then the specimen is dipped quickly in the electroplating bath after rinsing with distilled water. The produced electroplate was tested with different measurement techniques, chosen based on the requirement for a PEM fuel cell bipolar plate, including X-ray diffraction, EDAX, SEM, corrosion resistance, thickness measurement, microhardness, and electrical conductivity.

  11. Storm time heavy ion outflow at mid-latitudes

    SciTech Connect

    Yeh, H.C.; Foster, J.C. )

    1990-06-01

    Local ionospheric observations with the Millstone Hill incoherent scatterradar reveal an upward ion bulk velocity in excess of 3 km s{sup {minus} 1} at 1,000 km altitude during the very large magnetic storm on February 8, 1986. The upward flux of O{sup +} ions exceeded 3 {times} 10{sup 9} cm{sup {minus}2} s{sup {minus}1} at 42{degree} geodetic latitude (55{degree} {Lambda}) for a 3-hour period around 18 MLT during the event. Frictinal ion heating with ion temperatures in excess of 4,000 K at 500 km altitude was observed by the radar in the vicinity of the ion outflow event. Satellite observations place the ion outflow event within a region of intense ion and electron precipitation on field lines associated with the storm-perturbed ring current. For a one-dimensional analysis of the observed plasma profiles, continuity considerations indicate a region of intense O{sup +} production (200 cm{sup {minus}3} s{sup {minus}1}) as well as significant upward acceleration (5-10 m s{sup {minus}2}) in the region between 600 km and 800 km altitude where the outflow approaches supersonic speed. Ionizing collisions involving fast backsplash neutral O atoms (Torr et al., 1974) produced by ring current heavy ion precipitation can provide sufficient upward momentum to account for the acceleration in the observed outflowing thermal O{sup +} fluxes. Alternatively, the outflow event can be explained in terms of a time-dependent diffusion process triggered by a sudden change in the frictional heating rate in the collision-dominated F region (St.-Maurice, 1989). The concurrence of rapid ion convection and energetic ring current precipitation is unique at mid-latitudes during intense magnetic storms. Under these conditions, the observations indicate that the mid-latitude ionosphere constitutes a significant source of upflowing thermal O{sup +} fluxes to the overlying magnetosphere.

  12. Bright crater outflows: Possible emplacement mechanisms

    NASA Technical Reports Server (NTRS)

    Chadwick, D. John; Schaber, Gerald G.; Strom, Robert G.; Duval, Darla M.

    1992-01-01

    Lobate features with a strong backscatter are associated with 43 percent of the impact craters cataloged in Magellan's cycle 1. Their apparent thinness and great lengths are consistent with a low-viscosity material. The longest outflow yet identified is about 600 km in length and flows from the 90-km-diameter crater Addams. There is strong evidence that the outflows are largely composed of impact melt, although the mechanisms of their emplacement are not clearly understood. High temperatures and pressures of target rocks on Venus allow for more melt to be produced than on other terrestrial planets because lower shock pressures are required for melting. The percentage of impact craters with outflows increases with increasing crater diameter. The mean diameter of craters without outflows is 14.4 km, compared with 27.8 km for craters with outflows. No craters smaller than 3 km, 43 percent of craters in the 10- to 30-km-diameter range, and 90 percent in the 80- to 100-km-diameter range have associated bright outflows. More melt is produced in the more energetic impact events that produce larger craters. However, three of the four largest craters have no outflows. We present four possible mechanisms for the emplacement of bright outflows. We believe this 'shotgun' approach is justified because all four mechanisms may indeed have operated to some degree.

  13. Interactions between gravity waves and cold air outflows in a stably stratified uniform flow

    NASA Technical Reports Server (NTRS)

    Lin, Yuh-Lang; Wang, Ting-An; Weglarz, Ronald P.

    1993-01-01

    Interactions between gravity waves and cold air outflows in a stably stratified uniform flow forced by various combinations of prescribed heat sinks and sources are studied using a hydrostatic two-dimensional nonlinear numerical model. The formation time for the development of a stagnation point or reversed flow at the surface is not always directly proportional to the Froude number when wave reflections exist from upper levels. A density current is able to form by the wave-otuflow interaction, even though the Froude number is greater than a critical value. This is the result of the wave-outflow interaction shifting the flow response to a different location in the characteristic parameter space. A density current is able to form or be destroyed due to the wave-outflow interaction between a traveling gravity wave and cold air outflow. This is proved by performing experiments with a steady-state heat sink and an additional transient heat source. In a quiescent fluid, a region of cold air, convergence, and upward motion is formed after the collision between two outflows produced by two prescribed heat sinks. After the collision, the individual cold air outflows lose their own identity and merge into a single, stationary, cold air outflow region. Gravity waves tend to suppress this new stationary cold air outflow after the collision. The region of upward motion associated with the collision is confined to a very shallow layer. In a moving airstream, a density current produced by a heat sink may be suppressed or enhanced nonlinearly by an adjacent heat sink due to the wave-outflow interaction.

  14. Interactions between gravity waves and cold air outflows in a stably stratified uniform flow

    NASA Astrophysics Data System (ADS)

    Lin, Yuh-Lang; Wang, Ting-An; Weglarz, Ronald P.

    1993-11-01

    Interactions between gravity waves and cold air outflows in a stably stratified uniform flow forced by various combinations of prescribed heat sinks and sources are studied using a hydrostatic two-dimensional nonlinear numerical model. The formation time for the development of a stagnation point or reversed flow at the surface is not always directly proportional to the Froude number when wave reflections exist from upper levels. A density current is able to form by the wave-otuflow interaction, even though the Froude number is greater than a critical value. This is the result of the wave-outflow interaction shifting the flow response to a different location in the characteristic parameter space. A density current is able to form or be destroyed due to the wave-outflow interaction between a traveling gravity wave and cold air outflow. This is proved by performing experiments with a steady-state heat sink and an additional transient heat source. In a quiescent fluid, a region of cold air, convergence, and upward motion is formed after the collision between two outflows produced by two prescribed heat sinks. After the collision, the individual cold air outflows lose their own identity and merge into a single, stationary, cold air outflow region. Gravity waves tend to suppress this new stationary cold air outflow after the collision. The region of upward motion associated with the collision is confined to a very shallow layer. In a moving airstream, a density current produced by a heat sink may be suppressed or enhanced nonlinearly by an adjacent heat sink due to the wave-outflow interaction.

  15. Tobacco Use in Bipolar Disorder

    PubMed Central

    Thomson, Daniel; Berk, Michael; Dodd, Seetal; Rapado-Castro, Marta; Quirk, Shae E.; Ellegaard, Pernille K.; Berk, Lesley; Dean, Olivia M.

    2015-01-01

    Tobacco use in mental health in general and bipolar disorder in particular remains disproportionally common, despite declining smoking rates in the community. Furthermore, interactions between tobacco use and mental health have been shown, indicating the outcomes for those with mental health disorders are impacted by tobacco use. Factors need to be explored and addressed to improve outcomes for those with these disorders and target specific interventions for people with psychiatric illness to cease tobacco smoking. In the context of bipolar disorder, this review explores; the effects of tobacco smoking on symptoms, quality of life, suicidal behaviour, the biological interactions between tobacco use and bipolar disorder, the interactions between tobacco smoking and psychiatric medications, rates and factors surrounding tobacco smoking cessation in bipolar disorder and suggests potential directions for research and clinical translation. The importance of this review is to bring together the current understanding of tobacco use in bipolar disorder to highlight the need for specific intervention. PMID:25912533

  16. Tobacco use in bipolar disorder.

    PubMed

    Thomson, Daniel; Berk, Michael; Dodd, Seetal; Rapado-Castro, Marta; Quirk, Shae E; Ellegaard, Pernille K; Berk, Lesley; Dean, Olivia M

    2015-04-30

    Tobacco use in mental health in general and bipolar disorder in particular remains disproportionally common, despite declining smoking rates in the community. Furthermore, interactions between tobacco use and mental health have been shown, indicating the outcomes for those with mental health disorders are impacted by tobacco use. Factors need to be explored and addressed to improve outcomes for those with these disorders and target specific interventions for people with psychiatric illness to cease tobacco smoking. In the context of bipolar disorder, this review explores; the effects of tobacco smoking on symptoms, quality of life, suicidal behavior, the biological interactions between tobacco use and bipolar disorder, the interactions between tobacco smoking and psychiatric medications, rates and factors surrounding tobacco smoking cessation in bipolar disorder and suggests potential directions for research and clinical translation. The importance of this review is to bring together the current understanding of tobacco use in bipolar disorder to highlight the need for specific intervention. PMID:25912533

  17. Big data for bipolar disorder.

    PubMed

    Monteith, Scott; Glenn, Tasha; Geddes, John; Whybrow, Peter C; Bauer, Michael

    2016-12-01

    The delivery of psychiatric care is changing with a new emphasis on integrated care, preventative measures, population health, and the biological basis of disease. Fundamental to this transformation are big data and advances in the ability to analyze these data. The impact of big data on the routine treatment of bipolar disorder today and in the near future is discussed, with examples that relate to health policy, the discovery of new associations, and the study of rare events. The primary sources of big data today are electronic medical records (EMR), claims, and registry data from providers and payers. In the near future, data created by patients from active monitoring, passive monitoring of Internet and smartphone activities, and from sensors may be integrated with the EMR. Diverse data sources from outside of medicine, such as government financial data, will be linked for research. Over the long term, genetic and imaging data will be integrated with the EMR, and there will be more emphasis on predictive models. Many technical challenges remain when analyzing big data that relates to size, heterogeneity, complexity, and unstructured text data in the EMR. Human judgement and subject matter expertise are critical parts of big data analysis, and the active participation of psychiatrists is needed throughout the analytical process. PMID:27068058

  18. 3D kinematics of the near-IR HH 223 outflow in L723

    NASA Astrophysics Data System (ADS)

    López, R.; Acosta-Pulido, J. A.; Estalella, R.; Gómez, G.; García-Lorenzo, B.

    2015-03-01

    In this work, we derive the full 3D kinematics of the near-infrared outflow HH 223, located in the dark cloud Lynds 723 (L723), where a well-defined quadrupolar CO outflow is found. HH 223 appears projected on to the two lobes of the east-west CO outflow. The radio continuum source VLA 2, towards the centre of the CO outflow, harbours a multiple system of low-mass young stellar objects. One of the components has been proposed to be the exciting source of the east-west CO outflow. From the analysis of the kinematics, we get further evidence on the relationship between the near-infrared and CO outflows and on the location of their exciting source. The proper motions were derived using multi-epoch, narrow-band H2 (2.122 μm line) images. Radial velocities were derived from the 2.122 μm line of the spectra. Because of the extended (˜5 arcmin), S-shaped morphology of the target, the spectra were obtained with the multi-object-spectroscopy (MOS) observing mode using the instrument Long-Slit Intermediate Resolution Infrared Spectrograph (LIRIS) at the 4.2 m William Herschel Telescope. To our knowledge, this work is the first time that MOS observing mode has been successfully used in the near-infrared range for an extended target.

  19. Bipolar disorder in women

    PubMed Central

    Parial, Sonia

    2015-01-01

    Bipolar affective disorder in women is a challenging disorder to treat. It is unique in its presentation in women and characterized by later age of onset, seasonality, atypical presentation, and a higher degree of mixed episodes. Medical and psychiatric co-morbidity adversely affects recovery from the bipolar disorder (BD) more often in women. Co-morbidity, particularly thyroid disease, migraine, obesity, and anxiety disorders occur more frequently in women while substance use disorders are more common in men. Treatment of women during pregnancy and lactation is challenging. Pregnancy neither protects nor exacerbates BD, and many women require continuation of medication during the pregnancy. The postpartum period is a time of high risk for onset and recurrence of BD in women. Prophylaxis with mood stabilizers might be needed. Individualized risk/benefits assessments of pregnant and postpartum women with BD are required to promote the health of the women and to avoid or limit exposure of the fetus or infant to potential adverse effects of medication. PMID:26330643

  20. The Orion Fingers: Near-IR Spectral Imaging of an Explosive Outflow

    NASA Astrophysics Data System (ADS)

    Youngblood, Allison; Ginsburg, Adam; Bally, John

    2016-06-01

    We present near-IR (1.1–2.4 μm) position–position–velocity cubes of the 500 year old Orion BN/KL explosive outflow with spatial resolution 1″ and spectral resolution 86 km s‑1. We construct integrated intensity maps free of continuum sources of 15 H2 and [Fe ii] lines while preserving kinematic information of individual outflow features. Included in the detected H2 lines are the 1-0 S(1) and 1-0 Q(3) transitions, allowing extinction measurements across the outflow. Additionally, we present dereddened flux ratios for over two dozen outflow features to allow for the characterization of the true excitation conditions of the BN/KL outflow. All of the ratios show the dominance of the shock excitation of the H2 emission, although some features exhibit signs of fluorescent excitation from stellar radiation or J-type shocks. We also detect tracers of the PDR/ionization front north of the Trapezium stars in [O i] and [Fe ii] and analyze other observed outflows not associated with the BN/KL outflow.

  1. MULTIPLE FAST MOLECULAR OUTFLOWS IN THE PRE-PLANETARY NEBULA CRL 618

    SciTech Connect

    Lee, Chin-Fei; Huang, Po-Sheng; Sahai, Raghvendra; Sánchez Contreras, Carmen; Tay, Jeremy Jian Hao

    2013-11-01

    CRL 618 is a well-studied pre-planetary nebula. It has multiple highly collimated optical lobes, fast molecular outflows along the optical lobes, and an extended molecular envelope that consists of a dense torus in the equator and a tenuous round halo. Here we present our observations of this source in CO J = 3-2 and HCN J = 4-3 obtained with the Submillimeter Array at up to ∼0.''3 resolutions. We spatially resolve the fast molecular outflow region previously detected in CO near the central star and find it to be composed of multiple outflows that have similar dynamical ages and are oriented along the different optical lobes. We also detect fast molecular outflows further away from the central star near the tips of the extended optical lobes and a pair of equatorial outflows inside the dense torus. We find that two episodes of bullet ejections in different directions are needed, one producing the fast molecular outflows near the central star and one producing the fast molecular outflows near the tips of the extended optical lobes. One possibility to launch these bullets is a magneto-rotational explosion of the stellar envelope.

  2. The Role of Cosmic-Ray Pressure in Accelerating Galactic Outflows

    NASA Astrophysics Data System (ADS)

    Simpson, Christine M.; Pakmor, Rüdiger; Marinacci, Federico; Pfrommer, Christoph; Springel, Volker; Glover, Simon C. O.; Clark, Paul C.; Smith, Rowan J.

    2016-08-01

    We study the formation of galactic outflows from supernova (SN) explosions with the moving-mesh code AREPO in a stratified column of gas with a surface density similar to the Milky Way disk at the solar circle. We compare different simulation models for SN placement and energy feedback, including cosmic rays (CRs), and find that models that place SNe in dense gas and account for CR diffusion are able to drive outflows with similar mass loading as obtained from a random placement of SNe with no CRs. Despite this similarity, CR-driven outflows differ in several other key properties including their overall clumpiness and velocity. Moreover, the forces driving these outflows originate in different sources of pressure, with the CR diffusion model relying on non-thermal pressure gradients to create an outflow driven by internal pressure and the random-placement model depending on kinetic pressure gradients to propel a ballistic outflow. CRs therefore appear to be non-negligible physics in the formation of outflows from the interstellar medium.

  3. Observation of bias-dependent noise sources in a TiO{sub x}/TiO{sub y} bipolar resistive switching frame

    SciTech Connect

    Hyung Kim, Joo; Rahm Lee, Ah; Cheol Bae, Yoon; Ho Baek, Kwang; Sik Im, Hyun; Pyo Hong, Jin

    2014-02-24

    We report the conduction features associated with the evolution of oxygen ions (or vacancies) under bias for a TiO{sub x} (oxygen ion-rich)/TiO{sub y} (oxygen ion-deficient) bi-layer cell by identifying low-frequency noise sources. It is believed that a low resistance state enhances the formation of conductive filaments exchanging electrons through a nearest-neighbor hopping process, while a high resistance state (HRS) emphasizes the rupture of conductive filaments inside the insulating TiO{sub x} layer and a reduction/oxidation reaction at the oxide interfaces. The high resolution transmission electron microscope images of as-grown and HRS cells are also discussed.

  4. Jets and outflows from pre main sequence stars

    NASA Astrophysics Data System (ADS)

    Wassell, Edward Joseph, III

    2009-09-01

    Extensive research has been done on the evolution of young low mass T Tauri stars (TTS), and a paradigm has been developed that successfully explains how the star grows by the accretion of matter from a circumstellar disk. It is currently a matter of debate whether or not the same paradigm can be applied to the higher mass counterpart Herbig Ae stars. In this dissertation, I propose to address this issue. By investigating a wide range of phenomena using ground- based and satellite observing platforms, I will construct detailed observational pictures of the two prototypical Herbig Ae stars, HD163296 and AB Aur. Then, I will test whether or not this model can explain all the phenomena associated with these two stars. First, my research characterized the bipolar collimated outflow from HD163296. Using narrowband coronagraphic imagery with the Goddard Fabry-Perot, I discovered a chain of six previously unreported Herbig-Haro (HH) knots along the redshifted counterjet spanning greater than 27 arcseconds, and three HH knots along the blueshifted jet. Combining Hubble Space Telescope imagery and spectroscopy, I found a striking asymmetry in velocity, momentum and ionization between the two lobes of the outflow. Such asymmetries have been found in TTS, and can readily be explained through the same paradigm of magnetospheric accretion successfully applied to TTS. Next, by piecing together a wide range of data for AB Aur, I found evidence for magnetospheric accretion with the detection of excess continuum emission and semi-forbidden line emission in the ultraviolet. Reviewing archival spectra from the International Ultraviolet Explorer for AB Aur and five other Herbig Ae stars known to be powering microjets, I found a correlation between the Magnesium II wind absorption profile and inclination, which correlation strongly suggests that AB Aur is also powering a microjet, although currently, high resolution imagers have failed to detect jet signatures.

  5. Massive molecular outflows and evidence for AGN feedback from CO observations

    NASA Astrophysics Data System (ADS)

    Cicone, C.; Maiolino, R.; Sturm, E.; Graciá-Carpio, J.; Feruglio, C.; Neri, R.; Aalto, S.; Davies, R.; Fiore, F.; Fischer, J.; García-Burillo, S.; González-Alfonso, E.; Hailey-Dunsheath, S.; Piconcelli, E.; Veilleux, S.

    2014-02-01

    We study the properties of massive, galactic-scale outflows of molecular gas and investigate their impact on galaxy evolution. We present new IRAM PdBI CO(1-0) observations of local ultra-luminous infrared galaxies (ULIRGs) and quasar-hosts: a clear signature of massive and energetic molecular outflows, extending on kpc scales, is found in the CO(1-0) kinematics of four out of seven sources, with measured outflow rates of several 100 M⊙ yr-1. We combine these new observations with data from the literature, and explore the nature and origin of massive molecular outflows within an extended sample of 19 local galaxies. We find that starburst-dominated galaxies have an outflow rate comparable to their star formation rate (SFR), or even higher by a factor of ~2-4, implying that starbursts can indeed be effective in removing cold gas from galaxies. Nevertheless, our results suggest that the presence of an active galactic nucleus (AGN) can boost the outflow rate by a large factor, which is found to increase with the LAGN/Lbol ratio. The gas depletion time scales due to molecular outflows are anti-correlated with the presence and luminosity of an AGN in these galaxies, and range from a few hundred million years in starburst galaxies down to just a few million years in galaxies hosting powerful AGNs. In quasar hosts, the depletion time scales due to the outflow are much shorter than the depletion time scales due to star formation. We estimate the outflow kinetic power and find that, for galaxies hosting powerful AGNs, it corresponds to about 5% of the AGN luminosity, as expected by models of AGN feedback. Moreover, we find that momentum rates of about 20 LAGN/c are common among the AGN-dominated sources in our sample. For "pure" starburst galaxies, our data tentatively support models in which outflows are mostly momentum-driven by the radiation pressure from young stars onto dusty clouds. Overall, our results indicate that, although starbursts are effective in powering

  6. Experimental demonstration of an inertial collimation mechanism in nested outflows.

    PubMed

    Yurchak, R; Ravasio, A; Pelka, A; Pikuz, S; Falize, E; Vinci, T; Koenig, M; Loupias, B; Benuzzi-Mounaix, A; Fatenejad, M; Tzeferacos, P; Lamb, D Q; Blackman, E G

    2014-04-18

    Interaction between a central outflow and a surrounding wind is common in astrophysical sources powered by accretion. Understanding how the interaction might help to collimate the inner central outflow is of interest for assessing astrophysical jet formation paradigms. In this context, we studied the interaction between two nested supersonic plasma flows generated by focusing a long-pulse high-energy laser beam onto a solid target. A nested geometry was created by shaping the energy distribution at the focal spot with a dedicated phase plate. Optical and x-ray diagnostics were used to study the interacting flows. Experimental results and numerical hydrodynamic simulations indeed show the formation of strongly collimated jets. Our work experimentally confirms the "shock-focused inertial confinement" mechanism proposed in previous theoretical astrophysics investigations. PMID:24785042

  7. Experimental Demonstration of an Inertial Collimation Mechanism in Nested Outflows

    NASA Astrophysics Data System (ADS)

    Yurchak, R.; Ravasio, A.; Pelka, A.; Pikuz, S.; Falize, E.; Vinci, T.; Koenig, M.; Loupias, B.; Benuzzi-Mounaix, A.; Fatenejad, M.; Tzeferacos, P.; Lamb, D. Q.; Blackman, E. G.

    2014-04-01

    Interaction between a central outflow and a surrounding wind is common in astrophysical sources powered by accretion. Understanding how the interaction might help to collimate the inner central outflow is of interest for assessing astrophysical jet formation paradigms. In this context, we studied the interaction between two nested supersonic plasma flows generated by focusing a long-pulse high-energy laser beam onto a solid target. A nested geometry was created by shaping the energy distribution at the focal spot with a dedicated phase plate. Optical and x-ray diagnostics were used to study the interacting flows. Experimental results and numerical hydrodynamic simulations indeed show the formation of strongly collimated jets. Our work experimentally confirms the "shock-focused inertial confinement" mechanism proposed in previous theoretical astrophysics investigations.

  8. The IRS 1 circumstellar disk, and the origin of the jet and CO outflow in B5

    NASA Technical Reports Server (NTRS)

    Langer, W. D.; Velusamy, T.; Xie, T.; Levin, S. M. (Principal Investigator)

    1996-01-01

    We report the discovery of the inner edge of the high velocity CO outflow associated with the bipolar jet originating from IRS 1 in Barnard 5 and the first ever resolution of its circumstellar disk in the 2.6 mm dust continuum and C18O. From high spatial resolution observations made with the Owens Valley Millimeter Array we are able to locate the origin of the outflow to within approximately 500 AU on either side of IRS 1 and apparently at the edge of, or possibly within, its circumstellar disk. The orientation of the continuum disk is perpendicular to the highly collimated jet outflow recently seen in optical emission at much farther distances. The disk has been detected in C18O giving a disk mass approximately 0.16 M (solar). Our HCO+ and HCN maps indicate significant chemical differentiation in the circumstellar region on small scales with HCO+ tracing an extended disk of material. The 12CO interferometer maps of the outflow show two conelike features originating at IRS 1, the blue one fanning open to the northeast and the red one to the southwest. The vertices of the cones are on either side of the circumstellar disk and have a projected opening angle of about 90 degrees. The intrinsic opening angle is in the range of 60 degrees-90 degrees which leads to significant interaction between outflow and infall.

  9. THE HIGH-VELOCITY MOLECULAR OUTFLOWS IN MASSIVE CLUSTER-FORMING REGION G10.6-0.4

    SciTech Connect

    Liu Hauyu Baobab; Ho, Paul T. P.; Zhang Qizhou E-mail: pho@asiaa.sinica.edu.t

    2010-12-20

    We report the arcsecond resolution Submillimeter Array observations of the {sup 12}CO (2-1) transition in the massive cluster-forming region G10.6-0.4. In these observations, the high-velocity {sup 12}CO emission is resolved into individual outflow systems, which have a typical size scale of a few arcseconds. These molecular outflows are energetic and are interacting with the ambient molecular gas. By inspecting the shock signatures traced by CH{sub 3}OH, SiO, and HCN emissions, we suggest that abundant star formation activities are distributed over the entire 0.5 pc scale dense molecular envelope. The star formation efficiency over one global free-fall timescale (of the 0.5 pc molecular envelope, {approx}10{sup 5} years) is about a few percent. The total energy feedback of these high-velocity outflows is higher than 10{sup 47} erg, which is comparable to the total kinetic energy in the rotational motion of the dense molecular envelope. From order-of-magnitude estimations, we suggest that the energy injected from the protostellar outflows is capable of balancing the turbulent energy dissipation. No high-velocity bipolar molecular outflow associated with the central OB cluster is directly detected, which can be due to the photoionization.

  10. An interferometric study of the HH 288 molecular outflow

    NASA Astrophysics Data System (ADS)

    Gueth, F.; Schilke, P.; McCaughrean, M. J.

    2001-09-01

    We present an interferometric study of the CO line emission in the HH 288 molecular outflow. The IRAM Plateau de Bure interferometer was used to obtain an 11-field mosaic covering the whole flow ( ~ 2 pc) with an angular resolution of about 3.5'' (7000 AU at a distance of 2 kpc). The data were complemented with short-spacings derived from IRAM 30-m observations. The exciting source of HH 288, IRAS 00342+6347, is a young (dynamical age of the outflow =~ a few 104 years) intermediate-mass (bolometric luminosity =~ 500lsun , envelope mass =~ 6 to 30msun ) embedded protostar. This source is likely to be an intermediate-mass counterpart of a classical Class 0 low-mass protostar. HH 288 is actually a quadrupolar outflow, and the angular resolution provided by the interferometric observations allows us to rule out models involving limb-brightened walls of a wide-angle single flow to explain such a morphology. The presence of two protostars in the central condensation is the most appealing explanation to account for the presence of the two flows. While the small East-West flow has a quite simple morphology and kinematics, the large North-South flow includes several overlapping structures, created by successive ejection events. Large collimated limb-brightened cavities are observed, with high-velocity material located along or near the flow axis. The internal structure of HH 288, including morphological coincidence between the CO and H2 emission, supports prompt entrainment at the head of large bow-shocks as the main formation process of molecular outflows from intermediate-mass protostars. Based on observations carried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).

  11. Psychotherapeutic Treatment of Bipolar Depression.

    PubMed

    McMahon, Kibby; Herr, Nathaniel R; Zerubavel, Noga; Hoertel, Nicolas; Neacsiu, Andrada D

    2016-03-01

    The gold standard for treating bipolar depression is based on the combination of mood stabilizers and psychotherapy. Therefore, the authors present evidence-based models and promising approaches for psychotherapy for bipolar depression. Cognitive-behavioral therapy, family focused therapy, interpersonal and social rhythm therapy, mindfulness-based cognitive therapy, and dialectical behavior therapy are discussed. Behavioral activation, the cognitive behavioral analysis system of psychotherapy, and the unified protocol as promising future directions are presented. This review informs medical providers of the most appropriate referral guidelines for psychotherapy for bipolar depression. The authors conclude with a decision tree delineating optimal referrals to each psychotherapy approach. PMID:26876317

  12. Large-scale outflow in quasar LBQS J1206+1052: HST/COS observations

    NASA Astrophysics Data System (ADS)

    Chamberlain, Carter; Arav, Nahum

    2015-11-01

    Using two orbits of HST/COS archival observations, we measure the location and energetics of a quasar outflow from LBQS J1206+1052. From separate collisional excitation models of observed N III/N III* and S III/S III* troughs, we measure the electron number density n_e of the outflow. Both independent determinations are in full agreement and yield n_e =10^{3.0} cm^{-3}. Combining this value of n_e with photoionization simulations, we determine that the outflow is located 840 pc from the central source. The outflow has a velocity of 1400 km s-1, a mass flux of 9 M⊙ yr-1 and a kinetic luminosity of 1042.8 erg s-1. The distance finding is much larger than predicted from radiative acceleration models, but is consistent with recent empirical distance determinations.

  13. Ion bipolar junction transistors.

    PubMed

    Tybrandt, Klas; Larsson, Karin C; Richter-Dahlfors, Agneta; Berggren, Magnus

    2010-06-01

    Dynamic control of chemical microenvironments is essential for continued development in numerous fields of life sciences. Such control could be achieved with active chemical circuits for delivery of ions and biomolecules. As the basis for such circuitry, we report a solid-state ion bipolar junction transistor (IBJT) based on conducting polymers and thin films of anion- and cation-selective membranes. The IBJT is the ionic analogue to the conventional semiconductor BJT and is manufactured using standard microfabrication techniques. Transistor characteristics along with a model describing the principle of operation, in which an anionic base current amplifies a cationic collector current, are presented. By employing the IBJT as a bioelectronic circuit element for delivery of the neurotransmitter acetylcholine, its efficacy in modulating neuronal cell signaling is demonstrated. PMID:20479274

  14. Ion bipolar junction transistors

    PubMed Central

    Tybrandt, Klas; Larsson, Karin C.; Richter-Dahlfors, Agneta; Berggren, Magnus

    2010-01-01

    Dynamic control of chemical microenvironments is essential for continued development in numerous fields of life sciences. Such control could be achieved with active chemical circuits for delivery of ions and biomolecules. As the basis for such circuitry, we report a solid-state ion bipolar junction transistor (IBJT) based on conducting polymers and thin films of anion- and cation-selective membranes. The IBJT is the ionic analogue to the conventional semiconductor BJT and is manufactured using standard microfabrication techniques. Transistor characteristics along with a model describing the principle of operation, in which an anionic base current amplifies a cationic collector current, are presented. By employing the IBJT as a bioelectronic circuit element for delivery of the neurotransmitter acetylcholine, its efficacy in modulating neuronal cell signaling is demonstrated. PMID:20479274

  15. OUTFLOWS AND MASSIVE STARS IN THE PROTOCLUSTER IRAS 05358+3543

    SciTech Connect

    Ginsburg, Adam G.; Bally, John; Yan Chihung; Williams, Jonathan P. E-mail: John.Bally@colorado.ed

    2009-12-10

    We present new near-IR H{sub 2}, CO J = 2-1, and CO J = 3-2 observations to study outflows in the massive star-forming region IRAS 05358+3543. The Canada-France-Hawaii Telescope H{sub 2} images and James Clerk Maxwell Telescope CO data cubes of the IRAS 05358 region reveal several new outflows, most of which emerge from the dense cluster of submillimeter cores associated with the Sh 2-233IR NE cluster to the northeast of IRAS 05358. We used Apache Point Observatory JHK spectra to determine line-of-sight velocities of the outflowing material. Analysis of archival Very Large Array cm continuum data and previously published very long baseline interferometry observations reveal a massive star binary as a probable source of one or two of the outflows. We have identified probable sources for six outflows and candidate counterflows for seven out of a total of 11 seen to be originating from the IRAS 05358 clusters. We classify the clumps within Sh 2-233IR NE as an early protocluster and Sh 2-233IR SW as a young cluster, and conclude that the outflow energy injection rate approximately matches the turbulent decay rate in Sh 2-233IR NE.

  16. Multiple monopolar outflows driven by massive protostars in IRAS 18162-2048

    SciTech Connect

    Fernández-López, M.; Girart, J. M.; Curiel, S.; Fonfría, J. P.; Zapata, L. A.; Qiu, K. E-mail: girart@ieec.cat

    2013-11-20

    In this article, we present Combined Array for Research in Millimeter-wave Astronomy (CARMA) 3.5 mm observations and SubMillimeter Array (SMA) 870 μm observations toward the high-mass star-forming region IRAS 18162-2048, which is the core of the HH 80/81/80N system. Molecular emission from HCN, HCO{sup +}, and SiO traces two molecular outflows (the so-called northeast and northwest outflows). These outflows have their origin in a region close to the position of MM2, a millimeter source known to harbor two protostars. For the first time we estimate the physical characteristics of these molecular outflows, which are similar to those of 10{sup 3}-5 × 10{sup 3} L {sub ☉} protostars, and suggest that MM2 harbors high-mass protostars. High-angular resolution CO observations show an additional outflow due southeast. Also for the first time, we identify its driving source, MM2(E), and see evidence of precession. All three outflows have a monopolar appearance, but we link the NW and SE lobes, and explain their asymmetric shape as being a consequence of possible deflection.

  17. Outflows in Sodium Excess Objects

    NASA Astrophysics Data System (ADS)

    Park, Jongwon; Jeong, Hyunjin; Yi, Sukyoung

    2016-01-01

    van Dokkum and Conroy reported that some giant elliptical galaxies show extraordinarily strong Na I absorption lines and suggested that this is the evidence of unusually bottom-heavy initial mass function. Jeong et al. later studied galaxies with unexpectedly strong Na D absorption lines (Na D excess objects: NEOs) and showed that the origins of NEOs are different for different types of galaxies. According to their study, the origin of Na D excess seems to be related to interstellar medium (ISM) in late-type galaxies, but there seems to be no contributions from ISM in smooth-looking early-type galaxies. In order to test this finding, we measured the Doppler components in Na D lines of NEOs. We hypothesized that if Na D absorption line is related to ISM, the absorption line is more likely to be blueshifted in the spectrum by the motion of ISM caused by outflow. Many of late-type NEOs show blueshifted Na D absorption lines, so their origin seems related to ISM. On the other hand, smooth-looking early-type NEOs do not show Doppler departure and Na D excess in early-type NEOs is likely not related to ISM, which is consistent with the finding of Jeong et al.

  18. Asenapine for bipolar disorder

    PubMed Central

    Scheidemantel, Thomas; Korobkova, Irina; Rej, Soham; Sajatovic, Martha

    2015-01-01

    Asenapine (Saphris®) is an atypical antipsychotic drug which has been approved by the US Food and Drug Administration for the treatment of schizophrenia in adults, as well as the treatment of acute manic or mixed episodes of bipolar I in both adult and pediatric populations. Asenapine is a tetracyclic drug with antidopaminergic and antiserotonergic activity with a unique sublingual route of administration. In this review, we examine and summarize the available literature on the safety, efficacy, and tolerability of asenapine in the treatment of bipolar disorder (BD). Data from randomized, double-blind trials comparing asenapine to placebo or olanzapine in the treatment of acute manic or mixed episodes showed asenapine to be an effective monotherapy treatment in clinical settings; asenapine outperformed placebo and showed noninferior performance to olanzapine based on improvement in the Young Mania Rating Scale scores. There are limited data available on the use of asenapine in the treatment of depressive symptoms of BD, or in the maintenance phase of BD. The available data are inconclusive, suggesting the need for more robust data from prospective trials in these clinical domains. The most commonly reported adverse effect associated with use of asenapine is somnolence. However, the somnolence associated with asenapine use did not cause significant rates of discontinuation. While asenapine was associated with weight gain when compared to placebo, it appeared to be modest when compared to other atypical antipsychotics, and its propensity to cause increases in hemoglobin A1c or serum lipid levels appeared to be similarly modest. Asenapine does not appear to cause any clinically significant QTc prolongation. The most commonly reported extra-pyramidal symptom associated with asenapine was akathisia. Overall, asenapine appears to be a relatively well-tolerated atypical antipsychotic, effective in the treatment of acute manic and mixed episodes of BD. PMID:26674884

  19. Hydrodynamic Simulations of Jet- and Wind-driven Protostellar Outflows

    NASA Astrophysics Data System (ADS)

    Lee, Chin-Fei; Stone, James M.; Ostriker, Eve C.; Mundy, Lee G.

    2001-08-01

    We present two-dimensional hydrodynamic simulations of both jet- and wind-driven models for protostellar outflows in order to make detailed comparisons to the kinematics of observed molecular outflows. The simulations are performed with the ZEUS-2D hydrodynamic code using a simplified equation of state, simplified cooling and no external heating, and no self-gravity. In simulations of steady jets, swept-up ambient gas forms a thin shell that can be identified as a molecular outflow. We find a simple ballistic bow shock model is able to reproduce the structure and transverse velocity of the shell. Position-velocity (PV) diagrams for the shell cut along the outflow axis show a convex spur structure with the highest velocity at the bow tip and low-velocity red and blue components at any viewing angle. The power-law index of the mass-velocity (MV) relationship ranges from 1.5 to 3.5, depending strongly on the inclination. If the jet is time-variable, the PV diagrams show multiple convex spur structures, and the power-law index becomes smaller than the steady jet simulation. In simulations of isothermal steady wide-angle winds, swept-up ambient gas forms a thin shell that at early stages has a similar shape to the shell in the jet-driven model; it becomes broader at later times. We find the structure and kinematics of the shell is well described by a momentum-conserving model similar to that of Shu et al. (1991). In contrast to the results from jet simulations, the PV diagrams for the shell cut along the outflow axis show a lobe structure tilted with source inclination, with components that are primarily either red or blue unless the inclination is nearly in the plane of sky. The power-law index of the MV relationship ranges from 1.3 to 1.8. If the wind is time-variable, the PV diagrams also show multiple structures, and the power-law index becomes smaller than the steady wind simulation. Comparing the different simulations with observations, we find that some outflows

  20. Comparison of high-altitude production and ionospheric outflow contributions to O+ loss at Mars

    NASA Astrophysics Data System (ADS)

    Liemohn, Michael W.; Curry, Shannon M.; Fang, Xiaohua; Ma, Yingjuan

    2013-07-01

    Mars Test Particle model is used (with background parameters from a magnetohydrodynamic code) to simulate the transport of O+ ions in the near-Mars space environment to study the source processes responsible for ion escape. The MHD values at this altitude are used to inject an ionospheric outflow source of ions for the Mars Test Particle (MTP). The resulting loss distributions (in both real and velocity space) from this ionospheric source term are compared against those from high-altitude ionization mechanisms, in particular photoionization, charge exchange, and electron impact ionization, each of which has its own source regions, albeit overlapping. For the nominal MHD settings, this ionospheric outflow source contributes only 10% to the total O+ loss rate at solar maximum, predominantly via the central tail region. This percentage has very little dependence on the initial temperature, but a change in the initial ion density or bulk velocity directly alters this loss through the central tail. A density or bulk velocity increase of a factor of 10 makes the ionospheric outflow loss comparable in magnitude to the loss from the combined high-altitude sources. The spatial and velocity space distributions of escaping O+ are examined and compared for the various source terms to identify features specific to each ion source mechanism. For solar minimum conditions, the nominal MHD ionospheric outflow settings yield a 27% contribution to the total O+ loss rate, i.e., roughly equal to any one of the three high-altitude source terms with respect to escape.

  1. Magnetosphere sawtooth oscillations induced by ionospheric outflow.

    PubMed

    Brambles, O J; Lotko, W; Zhang, B; Wiltberger, M; Lyon, J; Strangeway, R J

    2011-06-01

    The sawtooth mode of convection of Earth's magnetosphere is a 2- to 4-hour planetary-scale oscillation powered by the solar wind-magnetosphere-ionosphere (SW-M-I) interaction. Using global simulations of geospace, we have shown that ionospheric O(+) outflows can generate sawtooth oscillations. As the outflowing ions fill the inner magnetosphere, their pressure distends the nightside magnetic field. When the outflow fluence exceeds a threshold, magnetic field tension cannot confine the accumulating fluid; an O(+)-rich plasmoid is ejected, and the field dipolarizes. Below the threshold, the magnetosphere undergoes quasi-steady convection. Repetition and the sawtooth period are controlled by the strength of the SW-M-I interaction, which regulates the outflow fluence. PMID:21636770

  2. Surgical therapy for benign prostatic hypertrophy/bladder outflow obstruction

    PubMed Central

    Thiruchelvam, Nikesh

    2014-01-01

    Monopolar transurethral resection of the prostate (TURP) with endoscopic electrocautery remains the gold standard surgical technique for benign prostatic hypertrophy (BPH) by which all new procedures are compared. We reviewed the current literature, and international urological guidelines and consensus opinion on various surgical options for BPH and present a brief overview of alternative techniques including bipolar TURP, transurethral incision of the prostate, transurethral vaporization of the prostate, laser prostatectomy (with holmium, thulium and potassium titanyl phosphate greenlight lasers) and open prostatectomy (with mention of new techniques including laparoscopic and robotic prostatectomy). Emerging, experimental and less established techniques are also described including endoscopic heat generation (transurethral microwave thermotherapy, radiofrequency transurethral needle ablation of the prostate, high intensity focused ultrasound, hot water induced thermotherapy, pulsed electromagnetic radiofrequency), injection therapy (transurethral ethanol ablation and botulinum toxin) and mechanical devices (intraprostatic stents and urethral lift devices). Despite a plethora of surgical options, none have realistically improved outcomes in the long-term compared with TURP. Improvements have been made on improving surgical morbidity and time in hospital. Questions remain in this area, including what specific elements of bladder outflow obstruction (BOO) result in damage to the urinary tract, how does BPH contribute to BOO and how much prostate volume reduction is necessary to relieve BOO or lower urinary tract symptoms. Given these unanswered questions and the multitude of procedures available, it is clear that appropriate counselling is necessary in all men who undergo BPH surgery. PMID:24744521

  3. Bipolar disorder and multiple sclerosis.

    PubMed

    Ybarra, Mariana Inés; Moreira, Marcos Aurélio; Araújo, Carolina Reis; Lana-Peixoto, Marco Aurélio; Teixeira, Antonio Lucio

    2007-12-01

    Bipolar disorder may be overrepresented in multiple sclerosis (MS) patients. Although research in this area is limited, studies assessing the nature of this association have focused on genetic aspects, adverse reaction to drugs and brain demyelinating lesions. Herein we report three patients with MS that also presented bipolar disorder. The coexistence of neurological and psychiatric symptoms in most MS relapses highlights the relevance of biological factors in the emergence of mood disorders in these patients. PMID:18345425

  4. Powerful Molecular Outflows in Nearby Active Galaxies

    NASA Astrophysics Data System (ADS)

    Veilleux, Sylvain; Meléndez, Marcio

    2014-07-01

    We report the results from a systematic search for molecular (OH 119 μm) outflows with Herschel-PACS† in a sample of 43 nearby (z < 0.3) galaxy mergers, mostly ultraluminous infrared galaxies (ULIRGs) and QSOs. We find that the character of the OH feature (strength of the absorption relative to the emission) correlates with that of the 9.7-μm silicate feature, a measure of obscuration in ULIRGs. Unambiguous evidence for molecular outflows, based on the detection of OH absorption profiles with median velocities more blueshifted than -50 km s-1, is seen in 26 (70%) of the 37 OH-detected targets, suggesting a wide-angle (~ 145°) outflow geometry. Conversely, unambiguous evidence for molecular inflows, based on the detection of OH absorption profiles with median velocities more redshifted than +50 km s-1, is seen in only 4 objects, suggesting a planar or filamentary geometry for the inflowing gas. Terminal outflow velocities of ~ -1000 km s-1 are measured in several objects, but median outflow velocities are typically ~ -200 km s-1. While the outflow velocities show no statistically significant dependence on the star formation rate, they are distinctly more blueshifted among systems with large AGN fractions and luminosities [log (L AGN/L ⊙) >= 11.8 +/- 0.3]. The quasars in these systems play a dominant role in driving the molecular outflows. In contrast, the most AGN dominated systems, where OH is seen purely in emission, show relatively modest OH line widths, despite their large AGN luminosities, perhaps indicating that molecular outflows subside once the quasar has cleared a path through the obscuring material.

  5. Internet use by patients with bipolar disorder: Results from an international multisite survey.

    PubMed

    Bauer, Rita; Conell, Jörn; Glenn, Tasha; Alda, Martin; Ardau, Raffaella; Baune, Bernhard T; Berk, Michael; Bersudsky, Yuly; Bilderbeck, Amy; Bocchetta, Alberto; Bossini, Letizia; Castro, Angela M Paredes; Cheung, Eric Yw; Chillotti, Caterina; Choppin, Sabine; Del Zompo, Maria; Dias, Rodrigo; Dodd, Seetal; Duffy, Anne; Etain, Bruno; Fagiolini, Andrea; Hernandez, Miryam Fernández; Garnham, Julie; Geddes, John; Gildebro, Jonas; Gonzalez-Pinto, Ana; Goodwin, Guy M; Grof, Paul; Harima, Hirohiko; Hassel, Stefanie; Henry, Chantal; Hidalgo-Mazzei, Diego; Kapur, Vaisnvy; Kunigiri, Girish; Lafer, Beny; Larsen, Erik R; Lewitzka, Ute; Licht, Rasmus W; Lund, Anne Hvenegaard; Misiak, Blazej; Monteith, Scott; Munoz, Rodrigo; Nakanotani, Takako; Nielsen, René E; O'Donovan, Claire; Okamura, Yasushi; Osher, Yamima; Piotrowski, Patryk; Reif, Andreas; Ritter, Philipp; Rybakowski, Janusz K; Sagduyu, Kemal; Sawchuk, Brett; Schwartz, Elon; Scippa, Ângela M; Slaney, Claire; Sulaiman, Ahmad H; Suominen, Kirsi; Suwalska, Aleksandra; Tam, Peter; Tatebayashi, Yoshitaka; Tondo, Leonardo; Vieta, Eduard; Vinberg, Maj; Viswanath, Biju; Volkert, Julia; Zetin, Mark; Whybrow, Peter C; Bauer, Michael

    2016-08-30

    There is considerable international interest in online education of patients with bipolar disorder, yet little understanding of how patients use the Internet and other sources to seek information. 1171 patients with a diagnosis of bipolar disorder in 17 countries completed a paper-based, anonymous survey. 81% of the patients used the Internet, a percentage similar to the general public. Older age, less education, and challenges in country telecommunications infrastructure and demographics decreased the odds of using the Internet. About 78% of the Internet users looked online for information on bipolar disorder or 63% of the total sample. More years of education in relation to the country mean, and feeling very confident about managing life decreased the odds of seeking information on bipolar disorder online, while having attended support groups increased the odds. Patients who looked online for information on bipolar disorder consulted medical professionals plus a mean of 2.3 other information sources such as books, physician handouts, and others with bipolar disorder. Patients not using the Internet consulted medical professionals plus a mean of 1.6 other information sources. The percentage of patients with bipolar disorder who use the Internet is about the same as the general public. Other information sources remain important. PMID:27391371

  6. Threat sensitivity in bipolar disorder.

    PubMed

    Muhtadie, Luma; Johnson, Sheri L

    2015-02-01

    Life stress is a major predictor of the course of bipolar disorder. Few studies have used laboratory paradigms to examine stress reactivity in bipolar disorder, and none have assessed autonomic reactivity to laboratory stressors. In the present investigation we sought to address this gap in the literature. Participants, 27 diagnosed with bipolar I disorder and 24 controls with no history of mood disorder, were asked to complete a complex working memory task presented as "a test of general intelligence." Self-reported emotions were assessed at baseline and after participants were given task instructions; autonomic physiology was assessed at baseline and continuously during the stressor task. Compared to controls, individuals with bipolar disorder reported greater increases in pretask anxiety from baseline and showed greater cardiovascular threat reactivity during the task. Group differences in cardiovascular threat reactivity were significantly correlated with comorbid anxiety in the bipolar group. Our results suggest that a multimethod approach to assessing stress reactivity-including the use of physiological parameters that differentiate between maladaptive and adaptive profiles of stress responding-can yield valuable information regarding stress sensitivity and its associations with negative affectivity in bipolar disorder. (PsycINFO Database Record (c) 2015 APA, all rights reserved). PMID:25688436

  7. Spin properties of supermassive black holes with powerful outflows

    NASA Astrophysics Data System (ADS)

    Daly, Ruth. A.

    2016-05-01

    Relationships between beam power and accretion disc luminosity are studied for a sample of 55 high excitation radio galaxies (HERG), 13 low excitation radio galaxies (LERG), and 29 radio loud quasars (RLQ) with powerful outflows. The ratio of beam power to disc luminosity tends to be high for LERG, low for RLQ, and spans the full range of values for HERG. Writing general expressions for the disc luminosity and beam power and applying the empirically determined relationships allows a function that parametrizes the spins of the holes to be estimated. Interestingly, one of the solutions that is consistent with the data has a functional form that is remarkably similar to that expected in the generalized Blandford-Znajek model with a magnetic field that is similar in form to that expected in magnetically arrested disk (MAD) and advection-dominated accretion flow (ADAF) models. Values of the spin function, obtained independent of specific outflow models, suggest that spin and active galactic nucleus type are not related for these types of sources. The spin function can be used to solve for black hole spin in the context of particular outflow models, and one example is provided.

  8. The role of superthermal electrons in high latitude ionospheric outflows

    NASA Astrophysics Data System (ADS)

    Glocer, A.; Khazanov, G. V.; Liemohn, M. W.; Toth, G.; Gombosi, T. I.

    2014-12-01

    It is well accepted that the ionosphere is a critical source of plasma for the magnetosphere, providing O+, H+, and He+ which can have wide ranging consequences for the space environment system. Changing ion composition affects magnetic reconnection in the magnetosphere, the ring current, and the wave environment which is important for high energy radiation belt electrons. Of the myriad of mechanisms that are important in determining the ionospheric outflow solution at high latitudes, we focus on the role of superthermal electron populations. It has been demonstrated in multiple studies that even small concentrations of superthermal electrons can have a dramatic effect on the outflow solution. In this presentation, we present simulation results using our Polar Wind Outflow Model (PWOM) and our SuperThermal Electron Transport (STET) code. We describe recent results on superthermal electrons role in defining the quiet time solar wind solution with comparisons to observations. We also discuss preliminary results that combine the PWOM and STET codes for a more comprehensive treatment of the impact of superthermal electrons.

  9. Thermospheric Wind Impacts on Ionospheric Upflow and Outflow

    NASA Astrophysics Data System (ADS)

    Burleigh, M.; Zettergren, M. D.

    2014-12-01

    Significant amounts of thermal ionospheric plasma can be transported to high altitudes in response to magnetospheric and atmospheric forcing. Soft electron precipitation serves as a heat source for the ambient F-region ionospheric electrons, which enhances the ambipolar electric field and induces upflowing ions. Frictional heating of ions from fast convection through the neutral atmosphere creates pressure-driven ion upflows. Finally, large neutral winds along the geomagnetic field may effectively lift or lower the F-region density peak. At regions above where ion upflows are typically initiated, transverse ion acceleration is thought to give upflowing ions sufficient energy to escape to the magnetosphere. This study examines how low-altitude upflow processes affect ion outflow, focusing particularly on the impacts of neutral winds. A new multi-fluid ionospheric model, which solves conservation equations for mass, momentum, and parallel and perpendicular energy is developed for this study. These fluid equations are solved for all species relevant to the E, F, and topside ionospheric regions and the system is closed through an electrostatic treatment of the auroral currents. This model is driven by the specification of field-aligned currents and a resonant transverse heating term. The model therefore encapsulates the basic ionospheric upflow processes and provides a simple way to approximate the effects of transverse heating and ion outflow. Using this model, individual species responses to electron precipitation, frictional heating, neutral winds, and transverse heating are examined to determine the effects of these low-altitude upflow processes on ion outflow. Results suggest that upflows, including those induced by neutral winds, can have a significant impact on the types and amounts of outflowing ions.

  10. The Environment and Outflow of the G-type T Tauri Star SU Aur

    NASA Astrophysics Data System (ADS)

    Grady, C.; Stapelfeldt, K.; Clampin, M.; Padgett, D.; Woodgate, B.; Henning, T.; Grinin, V.; Quirrenbach, A.; Stecklum, B.; Sitko, M.; Biggs, J.

    2001-12-01

    We present HST/STIS white light coronagraphic imaging data for the optically bright, classical T Tauri star, SU Aur. Previous optical imagery has detected "cometary" nebulosity beginning north of the star and wrapping around to the west and ultimately south (Nakajima & Golimowski 1995). The STIS data demonstrate that this nebulosity consists of a fan of nebulosity similar to that seen around R CrA, with wisp and clump structure down to the resolution limit of the telescope. This nebulosity has an opening angle of 70 degrees and a vertical extent of at least 12.2" (1842 AU at d=151 pc). The fan is visible in WFPC2 V, R, and I images, in addition to the STIS broad-band (0.2-1.0 micron) data, indicating detection of reflection nebulosity. A distinctive feature of the HST imagery of SU Aur is the presence of radial streamers seen at V and in the STIS data. The central streamer, which roughly bisects the fan of nebulosity, extends at least 8" (1200 AU) from the star at PA=295+/-1 degrees. The STIS data demonstrate that this feature is accompanied, on the opposite side of the star, by a string of bow-shaped nebulosities, extending 7.3" (1100 AU) from the star at PA=114+/-1 degrees. We interpret the fan of nebulosity as arising from the walls of a partially exposed outflow cavity. The scale and morphology of the central streamer and the PA=114 string of knots are consistent with the appearance of bipolar outflows as seen by STIS. SU Aur is a 4 Myr old (de Warf et al. 1998), 1.9+/-0.1 solar mass star. The bipolar outflow reported here is the second collimated outflow detected in association with an isolated, several million year old intermediate-mass star. Given the small number of coronagraphically imaged intermediate-mass stars, this result indicates that collimated outflows, similar to those routinely detected in association with lower mass T Tauri stars, appear to be common among their higher mass analogs and to persist for much of the star's pre-main sequence lifetime

  11. OBSERVATIONS OF MOLECULAR OUTFLOW IN CAR 291.6-01.9

    SciTech Connect

    Saul, M.; Saul, L. E-mail: luke.saul@space.unibe.ch

    2012-01-20

    We report the first observations of a dense molecular gas nebula and bipolar outflow in Car 291.6-01.9, showing characteristics of an embedded young stellar object (YSO). Using the Mopra radio telescope near Coonabarabaran, Australia, we image the kinematic structure of several emission features to examine physical properties within a molecular clump of mass {approx}3.2 {+-} 0.6 Multiplication-Sign 10{sup 3} M{sub Sun} in which a stellar cluster may be forming. Motivated by acquiring a more thorough understanding of star formation we ask what may have initiated collapse in the clump; observed outflow alignment is suggestive of {approx}1.0 pc distant massive star HD 308280 radiative-driven compression as a formation trigger for the dense core. An outflow derived age of <10{sup 6} years, together with significant C{sup 18}O and SO core depletion, support the case for the core as the host of an extremely YSO cluster.

  12. A Robust Measurement of the Mass Outflow Rate of the Galactic Outflow from NGC 6090

    NASA Astrophysics Data System (ADS)

    Chisholm, John; Tremonti, Christy A.; Leitherer, Claus; Chen, Yanmei

    2016-08-01

    To evaluate the impact of stellar feedback, it is critical to estimate the mass outflow rates of galaxies. Past estimates have been plagued by uncertain assumptions about the outflow geometry, metallicity, and ionization fraction. Here we use Hubble Space Telescope ultraviolet spectroscopic observations of the nearby starburst NGC 6090 to demonstrate that many of these quantities can be constrained by the data. We use the Si IV absorption lines to calculate the scaling of velocity (v), covering fraction (Cf), and density with distance from the starburst (r), assuming the Sobolev optical depth and a velocity law of the form: v~∝(1 - Ri/r)β (where Ri is the inner outflow radius). We find that the velocity (β=0.43) is consistent with an outflow driven by an r-2 force with the outflow radially accelerated, while the scaling of the covering fraction (Cf∝r-0.82) suggests that cool clouds in the outflow are in pressure equilibrium with an adiabatically expanding medium. We use the column densities of four weak metal lines and CLOUDY photoionization models to determine the outflow metallicity, the ionization correction, and the initial density of the outflow. Combining these values with the profile fitting, we find Ri = 63 pc, with most of the mass within 300 pc of the starburst. Finally, we find that the maximum mass outflow rate is 2.3 M⊙ yr-1 and the mass loading factor (outflow divided by the star formation rate) is 0.09, a factor of 10 lower than the value calculated using common assumptions for the geometry, metallicity and ionization structure of the outflow.

  13. High-Velocity HCO Emission Associated with the DR21 Molecular Outflow

    NASA Astrophysics Data System (ADS)

    Garden, R. P.; Carlstrom, J. E.

    1996-03-01

    The spatial and velocity distribution of HCO(+) J = 1-0 line emission from the DR 21 young stellar outflow is investigated with the Hat Creek millimeter interferometer. It is argued that the HCO(+) emission arises from two spatially distinct components: low-velocity clumps bordering the central DR 21 compact H II region, and extended high-velocity gas associated with the DR 21 outflow lobes. The high-velocity HCO(+) emission associated with the outflow lobes exhibits a remarkable spatial correlation with the distribution of shock-excited H2 line emission and is most likely formed by the compression and acceleration of ambient gas on interaction with a powerful young stellar wind. It is argued that the observed spatial correlation between HCO(+) and H2 line emission results from two interrelated effects: a small enhancement in the fractional abundance of HCO(+) in the shocked gas, and the more favorable conditions for excitation of the HCO(+) ion in the warm dense gas that comprises the outflow lobes. It is suggested that the DR 21 outflow source is one of the largest, most massive and energetic young stellar outflows discovered to date.

  14. Blowin' in the wind: feedback from QSO outflows at high-z

    NASA Astrophysics Data System (ADS)

    Cresci, G.

    2016-06-01

    Quasar feedback in the form of powerful outflows is invoked as a key mechanism to quench star formation in galaxies, although direct observational evidences are still scarce, probably because radiatively driven winds are rare as they arise during a short-lived phase. I will present near-IR integral field observations of a sample of high-z QSOs, in which we clearly resolve fast (up to 1500 km/s) extended (up to 13 kpc from the black hole) outflows in the [OIII] lines, whose high velocity and high mass outflow rate are unlikely to be sustained by star formation only. Moreover, Star Formation tracers in some of these objects show that the outflow position is anti-correlated with the star forming regions in the host galaxy, representing the first direct evidences of powerful outflows removing the gas from the host galaxy (`negative feedback'). Evidences of gas depletion in these source are also provided by the direct measurement of molecular gas from PDBI and ALMA observations. However, in one of the objects we also have evidences of the opposite mechanism, star formation triggered at the edges of the outflow ('positive feedback').

  15. Integrated neurobiology of bipolar disorder.

    PubMed

    Maletic, Vladimir; Raison, Charles

    2014-01-01

    From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity - reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition - limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional "unified field theory" of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial-neuronal interactions. Among these glial elements are microglia - the brain's primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the hypothalamic-pituitary-adrenal axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway, or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of bipolarity is one of the

  16. NEUTRAL GAS OUTFLOWS AND INFLOWS IN INFRARED-FAINT SEYFERT GALAXIES

    SciTech Connect

    Krug, Hannah B.; Veilleux, Sylvain; Rupke, David S. N. E-mail: veilleux@astro.umd.ed

    2010-01-10

    Previous studies of the Na I D interstellar absorption line doublet have shown that galactic winds occur in most galaxies with high infrared luminosities. However, in infrared-bright composite systems where a starburst coexists with an active galactic nucleus (AGN), it is unclear whether the starburst, the AGN, or both are driving the outflows. The present paper describes the results from a search for outflows in 35 infrared-faint Seyferts with 10{sup 9.9}< L{sub IR}/L{sub sun} < 10{sup 11}, or, equivalently, star formation rates (SFRs) of approx0.4-9 M{sub sun} yr{sup -1}, to attempt to isolate the source of the outflow. We find that the outflow detection rates for the infrared-faint Seyfert 1s (6%) and Seyfert 2s (18%) are lower than previously reported for infrared-luminous Seyfert 1s (50%) and Seyfert 2s (45%). The outflow kinematics of infrared-faint and infrared-bright Seyfert 2 galaxies resemble those of starburst galaxies, while the outflow velocities in Seyfert 1 galaxies are significantly larger. Taken together, these results suggest that the AGN does not play a significant role in driving the outflows in most infrared-faint and infrared-bright systems, except the high-velocity outflows seen in Seyfert 1 galaxies. Another striking result of this study is the high rate of detection of inflows in infrared-faint galaxies (39% of Seyfert 1s, 35% of Seyfert 2s), significantly larger than in infrared-luminous Seyferts (15%). This inflow may be contributing to the feeding of the AGN in these galaxies, and potentially provides more than enough material to power the observed nuclear activity over typical AGN lifetimes.

  17. Characterizing Quasar Outflows I: Sample, Spectral Measurements

    NASA Astrophysics Data System (ADS)

    Ganguly, Rajib; Christenson, D. H.; Richmond, J. M.; Derseweh, J. A.; Robbins, J. M.; Townsend, S. L.; Stark, M. A.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 11000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) measurements of UV emission line and continuum parameters. In this poster, we subjectively divide these quasars into four categories: broad absorption-line quasars (2700 objects), associated absorption-line quasars (1700 objects), reddened quasars (160 objects), and unabsorbed/unreddened quasars (6300 objects). We present measurements of the absorption (velocities, velocity widths, equivalent widths), composite spectral profiles of outflows as a function of velocity, as well as measurements of the continuum and CIV, MgII, and FeII emission-line properties. In accompanying posters, we add photometry from the rest-frame X-ray (ROSAT and Chandra), EUV (GALEX), optical (2MASS), and infrared (WISE) bands to complete the SED. The continuum and emission-line measurements from the SDSS spectra and accompanying photometry provides estimates on the black hole masses, bolometric luminsosities, and SED. We consider empirically how these affect the outflow properties. This material is based upon work supported by the National Aeronautics and Space Administration under

  18. Treatment of bipolar disorder.

    PubMed

    Geddes, John R; Miklowitz, David J

    2013-05-11

    We review recent developments in the acute and long-term treatment of bipolar disorder and identify promising future routes to therapeutic innovation. Overall, advances in drug treatment remain quite modest. Antipsychotic drugs are effective in the acute treatment of mania; their efficacy in the treatment of depression is variable with the clearest evidence for quetiapine. Despite their widespread use, considerable uncertainty and controversy remains about the use of antidepressant drugs in the management of depressive episodes. Lithium has the strongest evidence for long-term relapse prevention; the evidence for anticonvulsants such as divalproex and lamotrigine is less robust and there is much uncertainty about the longer term benefits of antipsychotics. Substantial progress has been made in the development and assessment of adjunctive psychosocial interventions. Long-term maintenance and possibly acute stabilisation of depression can be enhanced by the combination of psychosocial treatments with drugs. The development of future treatments should consider both the neurobiological and psychosocial mechanisms underlying the disorder. We should continue to repurpose treatments and to recognise the role of serendipity. We should also investigate optimum combinations of pharmacological and psychotherapeutic treatments at different stages of the illness. Clarification of the mechanisms by which different treatments affect sleep and circadian rhythms and their relation with daily mood fluctuations is likely to help with the treatment selection for individual patients. To be economically viable, existing psychotherapy protocols need to be made briefer and more efficient for improved scalability and sustainability in widespread implementation. PMID:23663953

  19. Herbig-Haro Objects and Mid-infrared Outflows in the Vela C Molecular Cloud

    NASA Astrophysics Data System (ADS)

    Zhang, Miaomiao; Wang, Hongchi; Henning, Thomas

    2014-08-01

    We have performed a deep [S II] λλ6717/6731 wide field Herbig-Haro (HH) object survey toward the Vela C molecular cloud with a sky coverage of about 2 deg2. In total, 18 new HH objects, HH 1090-1107, are discovered and the two previously known HH objects, HH 73-74, are also detected in our [S II] images. We also present an investigation of mid-infrared outflows in the Vela C molecular cloud using the Wide-field Infrared Survey Explorer images taken from AllWISE data release. Using the method suggested by Zhang & Wang, 11 extended green objects (EGOs) are identified to be the mid-infrared outflows, including 6 new mid-infrared outflows that have not been detected previously at other wavelengths and 5 mid-infrared counterparts of the HH objects detected in this work. Using the AllWISE Source Catalog and the source classification scheme suggested by Koenig et al., we have identified 56 young stellar object (YSO) candidates in the Vela C molecular cloud. The possible driving sources of the HH objects and EGOs are discussed based on the morphology of HH objects and EGOs and the locations of HH objects, EGOs and YSO candidates. Finally we associate 12 HH objects and 5 EGOs with 10 YSOs and YSO candidates. The median length of the outflows in Vela C is 0.35 pc and the outflows seem to be oriented randomly.

  20. Herbig-haro objects and mid-infrared outflows in the VELA C molecular cloud

    SciTech Connect

    Zhang, Miaomiao; Wang, Hongchi; Henning, Thomas

    2014-08-01

    We have performed a deep [S II] λλ6717/6731 wide field Herbig-Haro (HH) object survey toward the Vela C molecular cloud with a sky coverage of about 2 deg{sup 2}. In total, 18 new HH objects, HH 1090-1107, are discovered and the two previously known HH objects, HH 73-74, are also detected in our [S II] images. We also present an investigation of mid-infrared outflows in the Vela C molecular cloud using the Wide-field Infrared Survey Explorer images taken from AllWISE data release. Using the method suggested by Zhang and Wang, 11 extended green objects (EGOs) are identified to be the mid-infrared outflows, including 6 new mid-infrared outflows that have not been detected previously at other wavelengths and 5 mid-infrared counterparts of the HH objects detected in this work. Using the AllWISE Source Catalog and the source classification scheme suggested by Koenig et al., we have identified 56 young stellar object (YSO) candidates in the Vela C molecular cloud. The possible driving sources of the HH objects and EGOs are discussed based on the morphology of HH objects and EGOs and the locations of HH objects, EGOs and YSO candidates. Finally we associate 12 HH objects and 5 EGOs with 10 YSOs and YSO candidates. The median length of the outflows in Vela C is 0.35 pc and the outflows seem to be oriented randomly.

  1. Analysis of Asian Outflow over the Western Pacific using Observations from Trace-P

    NASA Technical Reports Server (NTRS)

    Jacob, Daniel J.

    2004-01-01

    Our analysis of the TRACE-P data focused on answering the following questions: 1) How do anthropogenic sources in Asia contribute to chemical outflow over the western Pacific in spring? 2) How does biomass burning in southeast Asia contribute to this outflow? 3) How can the TRACE-P observations be used to better quantify the sources of environmentally important gases in eastern Asia? Our strategy drew on a combination of data analysis and global 3-D modeling, as described below. We also contributed to the planning and execution of TRACE-P through service as mission scientist and by providing chemical model forecasts in the field.

  2. Targeting astrocytes in bipolar disorder.

    PubMed

    Peng, Liang; Li, Baoman; Verkhratsky, Alexei

    2016-06-01

    Astrocytes are homeostatic cells of the central nervous system, which are critical for development and maintenance of synaptic transmission and hence of synaptically connected neuronal ensembles. Astrocytic densities are reduced in bipolar disorder, and therefore deficient astroglial function may contribute to overall disbalance in neurotransmission and to pathological evolution. Classical anti-bipolar drugs (lithium salts, valproic acid and carbamazepine) affect expression of astroglial genes and modify astroglial signalling and homeostatic cascades. Many effects of both antidepressant and anti-bipolar drugs are exerted through regulation of glutamate homeostasis and glutamatergic transmission, through K(+) buffering, through regulation of calcium-dependent phospholipase A2 (that controls metabolism of arachidonic acid) or through Ca(2+) homeostatic and signalling pathways. Sometimes anti-depressant and anti-bipolar drugs exert opposite effects, and some effects on gene expression in drug treated animals are opposite in neurones vs. astrocytes. Changes in the intracellular pH induced by anti-bipolar drugs affect uptake of myo-inositol and thereby signalling via inositoltrisphosphate (InsP3), this being in accord with one of the main theories of mechanism of action for these drugs. PMID:27015045

  3. Northwestern Tharsis Latent Outflow Activity Mars

    NASA Technical Reports Server (NTRS)

    Dohm, J. M.; Anderson, R. C.; Baker, V. R.; Ferris, J. C.; Hare, T. M.; Strom, R. G.; Rudd, L.; Rice, J. W., Jr.; Scott, D. H.

    2000-01-01

    Previously defined outflow channels, which are indicated by relict landforms similar to those observed on Earth, signify ancient catastrophic flood events on Mars. These conspicuous geomorphic features are some of the most remarkable yet profound discoveries made by geologists to date. These outflow channels, which debouched tremendous volumes of water into topographic lows such as Chryse, Utopia, Elysium, and Hellas Planitiae, may represent the beginning of warmer and wetter climatic periods unlike the present-day cold and dry Mars. In addition to the previously identified outflow channels, observations permitted by the newly acquired Mars Orbiter Laser Altimeter (MOLA) data have revealed a system of gigantic valleys, referred to as the northwestern slope valleys (NSV), that are located to the northwest of a huge shield volcano, Arsia Mons, western hemisphere of Mars. These features generally correspond spatially to gravity lows similar to the easternmost, circum-Chryse outflow channel systems. Geologic investigations of the Tharsis region suggest that the large valley system pre-dates the construction of Arsia Mons and its extensive associated lava flows of mainly Late Hesperian and Amazonian age and coincides stratigraphically with the early development of the circum-Chryse outflow channel systems that debouch into Chryse Planitia. This newly identified system, the NSV, potentially signifies the largest flood event(s) ever recorded for the solar system. Additional information is contained in original extended abstract.

  4. Galaxy ecosystems: gas contents, inflows and outflows

    NASA Astrophysics Data System (ADS)

    Lu, Zhankui; Mo, H. J.; Lu, Yu

    2015-06-01

    We use a set of observational data for galaxy cold gas mass fraction and gas phase metallicity to constrain the content, inflow and outflow of gas in central galaxies hosted by haloes with masses between 1011 and 1012 M⊙. The gas contents in high-redshift galaxies are obtained by combining the empirical star formation histories and star formation models that relate star formation rate with the cold gas mass in galaxies. We find that the total baryon mass in low-mass galaxies is always much less than the universal baryon mass fraction since z = 2, regardless of star formation model adopted. The data for the evolution of the gas phase metallicity require net metal outflow at z ≲ 2, and the metal loading factor is constrained to be about 0.01, or about 60 per cent of the metal yield. Based on the assumption that galactic outflow is more enriched in metal than both the interstellar medium and the material ejected at earlier epochs, we are able to put stringent constraints on the upper limits for both the net accretion rate and the net mass outflow rate. The upper limits strongly suggest that the evolution of the gas phase metallicity and gas mass fraction for low-mass galaxies at z < 2 is not compatible with strong outflow. We speculate that the low star formation efficiency of low-mass galaxies is owing to some preventative processes that prevent gas from accreting into galaxies in the first place.

  5. Example of Reduced Turbulence during Thunderstorm Outflow.

    NASA Astrophysics Data System (ADS)

    Bowen, Brent M.

    1996-06-01

    The vertical structures of turbulence, winds, and temperatures are analyzed from a 92-m instrumented tower and a collocated acoustic sodar during an outflow episode from a weak thunderstorm over sloping terrain in northern New Mexico. Prior to the onset of the outflow, strong insolation and light winds caused unstable conditions during the middle part of a June day, as evidenced by the large values of horizontal and vertical turbulence coefficients ( and , respectively) extending from the surface up to at 1east 750 m above ground level (AGL). There was a dramatic change in wind direction and speed as the gust front passed during the early afternoon. The outflow was a well-defined jet, with its core reaching a maximum average of 16 m S1 at 120 m AGL. The and values decreased sharply throughout the outflow region, especially near the height of the wind speed maximum (120 m AGL), where reached a value of only 2°. Consequently, horizontal and vertical dispersion of a hypothetical pollutant could each decrease by about 55% at 12 m AGL to 87% at 120 m AGL up to several kilometers downwind. In turn, this could increase plume centerline concentrations by factors of 1.5 and 14 for releases at 12 and 120 m AOL, respectively. As a result of intensified winds and reduced turbulence in the outflow layer, elevated pollutant concentrations would rapidly be transported downwind before fumigation could lead to elevated pollutant levels at ground level.

  6. Comparing the contributions of ionospheric outflow and high-altitude production to O+ loss at Mars

    NASA Astrophysics Data System (ADS)

    Liemohn, Michael; Curry, Shannon; Fang, Xiaohua; Johnson, Blake; Fraenz, Markus; Ma, Yingjuan

    2013-04-01

    The Mars total O+ escape rate is highly dependent on both the ionospheric and high-altitude source terms. Because of their different source locations, they appear in velocity space distributions as distinct populations. The Mars Test Particle model is used (with background parameters from the BATS-R-US magnetohydrodynamic code) to simulate the transport of ions in the near-Mars space environment. Because it is a collisionless model, the MTP's inner boundary is placed at 300 km altitude for this study. The MHD values at this altitude are used to define an ionospheric outflow source of ions for the MTP. The resulting loss distributions (in both real and velocity space) from this ionospheric source term are compared against those from high-altitude ionization mechanisms, in particular photoionization, charge exchange, and electron impact ionization, each of which have their own (albeit overlapping) source regions. In subsequent simulations, the MHD values defining the ionospheric outflow are systematically varied to parametrically explore possible ionospheric outflow scenarios. For the nominal MHD ionospheric outflow settings, this source contributes only 10% to the total O+ loss rate, nearly all via the central tail region. There is very little dependence of this percentage on the initial temperature, but a change in the initial density or bulk velocity directly alters this loss through the central tail. However, a density or bulk velocity increase of a factor of 10 makes the ionospheric outflow loss comparable in magnitude to the loss from the combined high-altitude sources. The spatial and velocity space distributions of escaping O+ are examined and compared for the various source terms, identifying features specific to each ion source mechanism. These results are applied to a specific Mars Express orbit and used to interpret high-altitude observations from the ion mass analyzer onboard MEX.

  7. Discovery of very high velocity outflow in V Hydra - Wind from an accretion disk in a binary?

    NASA Technical Reports Server (NTRS)

    Sahai, R.; Wannier, P. G.

    1988-01-01

    High-resolution observations of lines from the CO v = 1-0 vibration-rotation band at 4.6 microns, taken with the FTS/KPNO 4-m telescope, are reported for the carbon-rich red giant V Hydra, which is surrounded by an extended expanding molecular envelope resulting from extensive mass loss. The spectrum shows, in addition to the expected absorption at the outflow velocity of the envelope, absorption extending up to 120 km/s bluewards of the stellar velocity. A comparison of the spectrum observed at two epochs shows that the high-velocity absorption features change with time. It is suggested that the observed high-velocity features in V Hydra arise in a high-velocity polar outflow from an accretion disk in a binary system, as proposed in the mass-loss model for bipolar envelopes by Morris (1988).

  8. Observations of Protostellar Outflow Feedback in Clustered Star Formation

    NASA Astrophysics Data System (ADS)

    Nakamura, F.

    2016-05-01

    We discuss the role of protostellar outflow feedback in clustered star formation using the observational data of recent molecular outflow surveys toward nearby cluster-forming clumps. We found that for almost all clumps, the outflow momentum injection rate is significantly larger than the turbulence dissipation rate. Therefore, the outflow feedback is likely to maintain supersonic turbulence in the clumps. For less massive clumps such as B59, L1551, and L1641N, the outflow kinetic energy is comparable to the clump gravitational energy. In such clumps, the outflow feedback probably affects significantly the clump dynamics. On the other hand, for clumps with masses larger than about 200 M⊙, the outflow kinetic energy is significantly smaller than the clump gravitational energy. Since the majority of stars form in such clumps, we conclude that outflow feedback cannot destroy the whole parent clump. These characteristics of the outflow feedback support the scenario of slow star formation.

  9. The near-infrared excitation of the HH 211 protostellar outflow

    NASA Astrophysics Data System (ADS)

    O'Connell, B.; Smith, M. D.; Froebrich, D.; Davis, C. J.; Eislöffel, J.

    2005-02-01

    The protostellar outflow HH 211 is of considerable interest since it is extremely young and highly collimated. Here, we explore the outflow through imaging and spectroscopy in the near-infrared to determine if there are further diagnostic signatures of youth. We confirm the detection of a near-infrared continuum of unknown origin. We propose that it is emitted by the driving millimeter source, escapes the core through tunnels, and illuminates features aligning the outflow. Narrow-band flux measurements of these features contain an unusually large amount of continuum emission. [FeII] emission at 1.644 μm has been detected and is restricted to isolated condensations. However, the characteristics of vibrational excitation of molecular hydrogen resemble those of older molecular outflows. We attempt to model the ordered structure of the western outflow as a series of shocks, finding that bow shocks with J-type dissociative apices and C-type flanks are consistent. Moreover, essentially the same conditions are predicted for all three bows except for a systematic reduction in speed and density with distance from the driving source. We find increased K-band extinctions in the bright regions as high as 2.9 mag and suggest that the bow shocks become visible where the outflow impacts on dense clumps of cloud material. We propose that the outflow is carved out by episodes of pulsating jets. The jets, driven by central explosive events, are responsible for excavating a central tunnel through which radiation temporarily penetrates. Based in part on observations collected at the German-Spanish Astronomical Center, Calar Alto, operated jointly by Max-Planck Institut für Astronomie and Instituto de Astrofísica de Andalucía (CSIC). Observations were also obtained with The United Kingdom Infrared Telescope, which is operated by the Joint Astronomy Centre on behalf of the UK Particle Physics and Astronomy Research Council.

  10. Outflows, dusty cores, and a burst of star formation in the North America and Pelican nebulae

    SciTech Connect

    Bally, John; Ginsburg, Adam; Probst, Ron; Reipurth, Bo; Shirley, Yancy L.; Stringfellow, Guy S. E-mail: aginsburg@eso.org E-mail: reipurth@ifa.hawaii.edu E-mail: Guy.Stringfellow@colorado.edu

    2014-12-01

    We present observations of near-infrared 2.12 μm molecular hydrogen outflows emerging from 1.1 mm dust continuum clumps in the North America and Pelican Nebula (NAP) complex selected from the Bolocam Galactic Plane Survey (BGPS). Hundreds of individual shocks powered by over 50 outflows from young stars are identified, indicating that the dusty molecular clumps surrounding the NGC 7000/IC 5070/W80 H II region are among the most active sites of ongoing star formation in the solar vicinity. A spectacular X-shaped outflow, MHO 3400, emerges from a young star system embedded in a dense clump more than a parsec from the ionization front associated with the Pelican Nebula (IC 5070). Suspected to be a binary, the source drives a pair of outflows with orientations differing by 80°. Each flow exhibits S-shaped symmetry and multiple shocks indicating a pulsed and precessing jet. The 'Gulf of Mexico', located south of the North America Nebula (NGC 7000), contains a dense cluster of molecular hydrogen objects (MHOs), Herbig-Haro (HH) objects, and over 300 young stellar objects (YSOs), indicating a recent burst of star formation. The largest outflow detected thus far in the North America and Pelican Nebula complex, the 1.6 parsec long MHO 3417 flow, emerges from a 500 M {sub ☉} BGPS clump and may be powered by a forming massive star. Several prominent outflows such as MHO 3427 appear to be powered by highly embedded YSOs only visible at λ > 70 μm. An 'activity index' formed by dividing the number of shocks by the mass of the cloud containing their source stars is used to estimate the relative evolutionary states of Bolocam clumps. Outflows can be used as indicators of the evolutionary state of clumps detected in millimeter and submillimeter dust continuum surveys.

  11. Zooplankton in the Arctic outflow

    NASA Astrophysics Data System (ADS)

    Soloviev, K. A.; Dritz, A. V.; Nikishina, A. B.

    2009-04-01

    Climate changes in the Arctic cause the changes in the current system that may have cascading effect on the structure of plankton community and consequently on the interlinked and delicately balanced food web. Zooplankton species are by definition incapable to perform horizontal moving. Their transport is connected with flowing water. There are zooplankton species specific for the definite water masses and they can be used as markers for the different currents. That allows us to consider zooplankton community composition as a result of water mixing in the studied area. Little is known however about the mechanisms by which spatial and temporal variability in advection affect dynamics of local populations. Ice conditions are also very important in the function of pelagic communities. Melting time is the trigger to all "plankton blooming" processes, and the duration of ice-free conditions determines the food web development in the future. Fram Strait is one of the key regions for the Arctic: the cold water outflow comes through it with the East Greenland Current and meets warm Atlantic water, the West Spitsbergen Current, producing complicated hydrological situation. During 2007 and 2008 we investigated the structure functional characteristics of zooplankton community in the Fram Strait region onboard KV "Svalbard" (April 2007, April and May 2008) and RV "Jan Mayen" (May 2007, August 2008). This study was conducted in frame of iAOOS Norway project "Closing the loop", which, in turn, was a part of IPY. During this cruises multidisciplinary investigations were performed, including sea-ice observations, CTD and ADCP profiling, carbon flux, nutrients and primary production measurements, phytoplankton sampling. Zooplankton was collected with the Hydro-Bios WP2 net and MultiNet Zooplankton Sampler, (mouth area 0.25 m2, mesh size 180 um).Samples were taken from the depth strata of 2000-1500, 1500-1000, 1000-500,500-200, 200-100, 100-60, 60-30, 30-0 m. Gut fluorescence

  12. Mathematical models of bipolar disorder

    NASA Astrophysics Data System (ADS)

    Daugherty, Darryl; Roque-Urrea, Tairi; Urrea-Roque, John; Troyer, Jessica; Wirkus, Stephen; Porter, Mason A.

    2009-07-01

    We use limit cycle oscillators to model bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about 1% of the United States adult population. We consider two non-linear oscillator models of a single bipolar patient. In both frameworks, we begin with an untreated individual and examine the mathematical effects and resulting biological consequences of treatment. We also briefly consider the dynamics of interacting bipolar II individuals using weakly-coupled, weakly-damped harmonic oscillators. We discuss how the proposed models can be used as a framework for refined models that incorporate additional biological data. We conclude with a discussion of possible generalizations of our work, as there are several biologically-motivated extensions that can be readily incorporated into the series of models presented here.

  13. Wind influence on a coastal buoyant outflow

    NASA Astrophysics Data System (ADS)

    Whitney, Michael M.; Garvine, Richard W.

    2005-03-01

    This paper investigates the interplay between river discharge and winds in forcing coastal buoyant outflows. During light winds a plume influenced by the Earth's rotation will flow down shelf (in the direction of Kelvin wave propagation) as a slender buoyancy-driven coastal current. Downwelling favorable winds augment this down-shelf flow, narrow the plume, and mix the water column. Upwelling favorable winds drive currents that counter the buoyancy-driven flow, spread plume waters offshore, and rapidly mix buoyant waters. Two criteria are developed to assess the wind influence on a buoyant outflow. The wind strength index (Ws) determines whether a plume's along-shelf flow is in a wind-driven or buoyancy-driven state. Ws is the ratio of the wind-driven and buoyancy-driven along-shelf velocities. Wind influence on across-shelf plume structure is rated with a timescale (ttilt) for the isopycnal tilting caused by wind-driven Ekman circulation. These criteria are used to characterize wind influence on the Delaware Coastal Current and can be applied to other coastal buoyant outflows. The Delaware buoyant outflow is simulated for springtime high-river discharge conditions. Simulation results and Ws values reveal that the coastal current is buoyancy-driven most of the time (∣Ws∣ < 1 on average). Wind events, however, overwhelm the buoyancy-driven flow (∣Ws∣ > 1) several times during the high-discharge period. Strong upwelling events reverse the buoyant outflow; they constitute an important mechanism for transporting fresh water up shelf. Across-shelf plume structure is more sensitive to wind influence than the along-shelf flow. Values of ttilt indicate that moderate or strong winds persisting throughout a day can modify plume width significantly. Plume widening during upwelling events is accompanied by mixing that can erase the buoyant outflow.

  14. MAJOR CONTRIBUTOR TO AGN FEEDBACK: VLT X-SHOOTER OBSERVATIONS OF S IV BALQSO OUTFLOWS

    SciTech Connect

    Borguet, Benoit C. J.; Arav, Nahum; Edmonds, Doug; Chamberlain, Carter; Benn, Chris

    2013-01-01

    We present the most energetic BALQSO outflow measured to date, with a kinetic luminosity of at least 10{sup 46} erg s{sup -1}, which is 5% of the bolometric luminosity of this high Eddington ratio quasar. The associated mass-flow rate is 400 solar masses per year. Such kinetic luminosity and mass-flow rate should provide strong active galactic nucleus feedback effects. The outflow is located at about 300 pc from the quasar and has a velocity of roughly 8000 km s{sup -1}. Our distance and energetic measurements are based in large part on the identification and measurement of S IV and S IV* broad absorption lines (BALs). The use of this high-ionization species allows us to generalize the result to the majority of high-ionization BALQSOs that are identified by their C IV absorption. We also report the energetics of two other outflows seen in another object using the same technique. The distances of all three outflows from the central source (100-2000 pc) suggest that we observe BAL troughs much farther away from the central source than the assumed acceleration region of these outflows (0.01-0.1 pc).

  15. Major Contributor to AGN Feedback: VLT X-shooter Observations of S IV BALQSO Outflows

    NASA Astrophysics Data System (ADS)

    Borguet, Benoit C. J.; Arav, Nahum; Edmonds, Doug; Chamberlain, Carter; Benn, Chris

    2013-01-01

    We present the most energetic BALQSO outflow measured to date, with a kinetic luminosity of at least 1046 erg s-1, which is 5% of the bolometric luminosity of this high Eddington ratio quasar. The associated mass-flow rate is 400 solar masses per year. Such kinetic luminosity and mass-flow rate should provide strong active galactic nucleus feedback effects. The outflow is located at about 300 pc from the quasar and has a velocity of roughly 8000 km s-1. Our distance and energetic measurements are based in large part on the identification and measurement of S IV and S IV* broad absorption lines (BALs). The use of this high-ionization species allows us to generalize the result to the majority of high-ionization BALQSOs that are identified by their C IV absorption. We also report the energetics of two other outflows seen in another object using the same technique. The distances of all three outflows from the central source (100-2000 pc) suggest that we observe BAL troughs much farther away from the central source than the assumed acceleration region of these outflows (0.01-0.1 pc). Based on observations collected at the European Southern Observatory, Chile, PID: 87.B-0229.

  16. DIAGNOSTICS OF AGN-DRIVEN MOLECULAR OUTFLOWS IN ULIRGs FROM HERSCHEL-PACS OBSERVATIONS OF OH AT 119 μm

    SciTech Connect

    Spoon, H. W. W.; Lebouteiller, V.; Farrah, D.; González-Alfonso, E.; Bernard-Salas, J.; Urrutia, T.; Rigopoulou, D.; Verma, A.; Westmoquette, M. S.; Smith, H. A.; Afonso, J.; Pearson, C.; Cormier, D.; Efstathiou, A.; Borys, C.; Etxaluze, M.; Clements, D. L.

    2013-10-01

    We report on our observations of the 79 and 119 μm doublet transitions of OH for 24 local (z < 0.262) ULIRGs observed with Herschel-PACS as part of the Herschel ULIRG Survey (HERUS). Some OH 119 μm profiles display a clear P-Cygni shape and therefore imply outflowing OH gas, while other profiles are predominantly in absorption or are completely in emission. We find that the relative strength of the OH emission component decreases as the silicate absorption increases. This result locates the OH outflows inside the obscured nuclei. The maximum outflow velocities for our sources range from less than 100 to ∼2000 km s{sup –1}, with 15/24 (10/24) sources showing OH absorption at velocities exceeding 700 km s{sup –1} (1000 km s{sup –1}). Three sources show maximum OH outflow velocities exceeding that of Mrk231. Since outflow velocities above 500-700 km s{sup –1} are thought to require an active galactic nucleus (AGN) to drive them, about two-thirds of our ULIRG sample may host AGN-driven molecular outflows. This finding is supported by the correlation we find between the maximum OH outflow velocity and the IR-derived bolometric AGN luminosity. No such correlation is found with the IR-derived star formation rate. The highest outflow velocities are found among sources that are still deeply embedded. We speculate that the molecular outflows in these sources may be in an early phase of disrupting the nuclear dust veil before these sources evolve into less-obscured AGNs. Four of our sources show high-velocity wings in their [C II] fine-structure line profiles, implying neutral gas outflow masses of at least (2-4.5) × 10{sup 8} M{sub ☉}.

  17. Energetic auroral and polar ion outflow at DE 1 altitudes Magnitude, composition, magnetic activity dependence, and long-term variations

    NASA Technical Reports Server (NTRS)

    Yau, A. W.; Lenchyshyn, L.; Shelley, E. G.; Peterson, W. K.

    1985-01-01

    Data acquired from the Dynamics Explorer I Energetic Ion Composition Spectrometer in the period from September 1981 to May 1984 are used to determine the magnitude of the terrestrial ion outflow in the 0.01-17 keV/el range. The data are also employed to investigate the mass composition and topology (local time and invariant latitude distributions) of the ion outflow, as well as the outflow's magnetic activity dependence and long-term variation. The relative importance of auroral versus polar cap upflowing ions as a source of energetic plasma for various parts of the magnetosphere is examined.

  18. Refractory bipolar disorder and neuroprogression.

    PubMed

    da Costa, Sabrina C; Passos, Ives C; Lowri, Caroline; Soares, Jair C; Kapczinski, Flavio

    2016-10-01

    Immune activation and failure of physiologic compensatory mechanisms over time have been implicated in the pathophysiology of illness progression in bipolar disorder. Recent evidence suggests that such changes are important contributors to neuroprogression and may mediate the cross-sensitization of episode recurrence, trauma exposure and substance use. The present review aims to discuss the potential factors related to bipolar disorder refractoriness and neuroprogression. In addition, we will discuss the possible impacts of early therapeutic interventions as well as the alternative approaches in late stages of the disorder. PMID:26368941

  19. Bipolar dislocation of the clavicle.

    PubMed

    Jiang, Wei; Gao, Shu-Guang; Li, Yu-Sheng; Lei, Guang-Hua

    2012-11-01

    Bipolar dislocation of the clavicle at acromioclavicular and sternoclavicular joint is an uncommon traumatic injury. The conservative treatments adopted in the past is associated with redislocation dysfunction and deformity. A 41 years old lady with bipolar dislocation of right shoulder is treated surgically by open reduction and internal fixation by oblique T-plate at sternoclavicular joint and Kirschner wire stabilization at acromioclavicular joint. The patient showed satisfactory recovery with full range of motion of the right shoulder and normal muscular strength. The case reported in view of rarity and at 2 years followup. PMID:23325981

  20. Explosive Outflows from Forming Massive Stars

    NASA Astrophysics Data System (ADS)

    Bally, J.; Ginsburg, A.; Kasliwal, M. M.

    2016-05-01

    AO imaging of the near IR [Fe ii] and H2 lines and ALMA CO J = 2 - 1 data confirms the explosive nature of the BN/KL outflow in Orion. N-body interactions in compact groups may be responsible for the production of powerful, explosive protostellar outflows and luminous infrared flares. The Orion event may have been triggered by a protostellar merger. First results of a search for Orion-like events in 200 nearby galaxies with the SPitzer InfraRed Intensive Transients Survey (SPIRITS) are briefly discussed.

  1. Two New SiO Maser Sources in High-Mass Star-forming Regions

    NASA Astrophysics Data System (ADS)

    Cho, Se-Hyung; Yun, Youngjoo; Kim, Jaeheon; Liu, Tie; Kim, Kee-Tae; Choi, Minho

    2016-08-01

    Silicon monoxide (SiO) masers are rare in star-forming regions, with the exception of five known SiO maser sources. However, we detected two new SiO maser sources from infrared-loud clumps of the high-mass star-forming regions G19.61‑0.23 and G75.78+0.34. High angular resolution observations toward G19.61‑0.23 suggest that the deeply embedded young stellar object (YSO) of SMA1 is powering the SiO masers. In addition, the SiO v = 1, J = 1 \\to 0 line shows four spike features, while the v = 2 maser shows combined features of one spike and broad wing components, implying energetic activities of the YSO of SMA1 in the G19.61‑0.23 hot molecular core. The SiO v = 0, J = 2 \\to 1 emission shows bipolar outflows in the NE–SW direction with respect to the center of the SiO maser source. A high angular resolution map of the SiO v = 1, J = 2 \\to 1 maser in G75.78+0.34 shows that the SiO maser is associated with the CORE source at the earliest stage of high-mass star formation. Therefore, the newly detected SiO masers and their associated outflows will provide good probes for investigating this early high-mass star formation.

  2. Shells, outflows and star formation in the giant molecular cloud Monoceros R2

    NASA Astrophysics Data System (ADS)

    Xie, Taoling

    1992-09-01

    To improve our understanding about giant molecular clouds (GMC) associated with R-associations, a CO-12 J = 1-0 map of 167,000 spectra with 45 inch resolution and 25 inch spacing, a CO-13 J = 1-0 map of approximately 40,000 spectra with 1.5 foot resolution and 1 foot spacing, IRAS BIGMAP images, and maps of high density molecular tracers for the dense cores are obtained for the GMC Monoceros R2 (D = 830 plus or minus 50 pc). These data reveal that the large-scale structure of Mon R2 is dominated by an expanding bubble shell (approximately 30 pc) with front side moving towards us at a radial velocity of approximately 4-5 km/s. Distortions of this shell are obvious, suggesting of the inhomogeneity of the cloud before the formation of the bubble. There is no evidence for red-shifted shell at the far side of the bubble. There are at least two generations of star formation in Mon R2. The older generation of stars with an age of 6-10 x 106 years are represented mostly by reflection nebulae. The younger generation of stars with an age of approximately 105 years are represented mostly by IRAS point sources. It is proposed that the large-scale expanding bubble shell is the result of combined effects of ionizing flux and stellar winds originating from the older generation of young stellar objects, but perhaps dominated by O type stars which either are obscured or left main sequence. It is suggested that the formation of the younger generation of stars has been triggered by the older generation of stars. The main and the GGD12-15 cores are located on the large-scale expanding shell, and their harboring both generations of stars can be explained were the cores preexisting clumps. Our CO data reveal an eggplant-shaped bipolar outflow shell, whose shape can be satisfactorily modeled with radially directed stellar winds sweeping up ambient material with momentum conservation. An inversion method is implemented for analyzing dust emission spectra at FIR wavelengths in terms of a

  3. Radio recombination lines from fast shocks in molecular clouds, with application to bipolar flows

    NASA Technical Reports Server (NTRS)

    Mckee, Christopher F.; Hollenbach, David J.

    1987-01-01

    Detailed shock calculations are presented which demonstrate that fast dissociative shocks in molecular clouds produce detectable radio recombination lines and continuum lines, in addition to optical and infrared recombination lines. The theoretical results are applied to outflows from young stellar objects; bipolar flows are treated as massive, radiative winds. The calculations support Hasegawa and Akabane's (1984) interpretation of the H51-alpha line from Orion-KL as being due to a shock, and are consistent with the two-shock model of Chernoff, Hollenbach, and McKee (1982).

  4. Bipolar disorder: new perspectives in health care and prevention

    PubMed Central

    Leboyer, Marion; Kupfer, David J.

    2010-01-01

    Objectives High rates of misdiagnosis, delayed diagnosis, and lack of recognition and treatment of comorbid conditions often lead patients with bipolar illness to have a chronic course with high disability, unemployment rates, and mortality. Despite the recognition that long term outcome of bipolar disorder depends on systematic assessment of both inter-episodic dysfunctional domains and comorbid psychiatric and medical conditions, treatment of bipolar disorder still mostly focuses primarily on alleviation of acute symptoms and prevention of future recurrences. We propose here to review the evidence offering a current view of bipolar disorder defined as a chronic and progressive multi-system disorder, taking into account characteristics of each patient as well as biosignatures in order to help design personalized treatments. Data sources We conducted a systematic PubMed search of all English-language articles, published between 2000 and 2010, focusing on the English and French literature with bipolar disorder cross referenced with the following search terms: emotions, sleep, cognition, onset, comorbidities, psychosocial and medical interventions, outcome, and personalized medicine. Study Selection Forty-one papers were identified through the PubMed search described above and selected on the basis of addressing any combination of the search terms in conjunction with bipolar disorder. Data Extraction Since this is a review of the literature and not a meta-analysis, no data extraction occurred. Data Synthesis Current guidelines advocate the use of more or less similar treatment algorithms for all patients, ignoring the clinical, pathophysiological, and lifetime heterogeneity of bipolar disorder. Systematic assessment of inter-episodic dimensions along with comorbid medical and psychiatric risk factors should be performed along the life cycle in order to plan specific and personalized pharmacological, medical, and psychosocial interventions tailored to the needs of

  5. Glider observations of the Dotson Ice Shelf outflow

    NASA Astrophysics Data System (ADS)

    Miles, Travis; Lee, Sang Hoon; Wåhlin, Anna; Ha, Ho Kyung; Kim, Tae Wan; Assmann, Karen M.; Schofield, Oscar

    2016-01-01

    The Amundsen Sea is one of the most productive polynyas in the Antarctic per unit area and is undergoing rapid changes including a reduction in sea ice duration, thinning ice sheets, retreat of glaciers and the potential collapse of the Thwaites Glacier in Pine Island Bay. A growing body of research has indicated that these changes are altering the water mass properties and associated biogeochemistry within the polynya. Unfortunately difficulties in accessing the remote location have greatly limited the amount of in situ data that has been collected. In this study data from a Teledyne-Webb Slocum glider was used to supplement ship-based sampling along the Dotson Ice Shelf (DIS). This autonomous underwater vehicle revealed a detailed view of a meltwater laden outflow from below the western flank of the DIS. Circumpolar Deep Water intruding onto the shelf drives glacial melt and the supply of macronutrients that, along with ample light, supports the large phytoplankton blooms in the Amundsen Sea Polynya. Less well understood is the source of micronutrients, such as iron, necessary to support this bloom to the central polynya where chlorophyll concentrations are highest. This outflow region showed decreasing optical backscatter with proximity to the bed indicating that particulate matter was sourced from the overlying glacier rather than resuspended sediment. This result suggests that particulate iron, and potentially phytoplankton primary productivity, is intrinsically linked to the magnitude and duration of sub-glacial melt from Circumpolar Deep Water intrusions onto the shelf.

  6. Flood routing of the Maja outflow across Xanthe Terra

    NASA Technical Reports Server (NTRS)

    Dehon, R. A.

    1991-01-01

    The object is to trace a single flood crest through the Maja outflow system and to evaluate the effects of topography on ponding and multiple channel routing. Maja Valles provides a good model because it has a single source and a well defined channel system. The 1500 km long Maja Valles originates in Juventae Chasma. The outflow system stretches 1100 km northward along the Lunae Planum/Xanthe Terra boundary, then eastward across the Xanthe Terra highlands. It descends to Chryse Planitia where it extends northeastward toward the middle of the basin. It is concluded that flood routing through multiple channels and retardation in local impoundments are responsible for breakup of the initial flood crest and the formation of multiple flood crests. Recombined flow near the mouths of these canyons results in an extended flow regime and multiple flood surges. As a result of ponding along the flood course, depositional sites are localized and renewed erosion downstream (from ponded sites) results in sediment source areas not greatly removed from depositional sites.

  7. Spitzer spectral line mapping of the HH211 outflow

    NASA Astrophysics Data System (ADS)

    Dionatos, O.; Nisini, B.; Cabrit, S.; Kristensen, L.; Pineau Des Forêts, G.

    2010-10-01

    Context. Jets from the youngest protostars are often detected only at mm wavelengths, by means of line emission of CO and SiO. However, it is not yet clear whether these jets are mostly molecular or atomic, nor whether they trace ejected gas or an entrained layer around an embedded atomic jet. Aims: We investigate the warm gas content of the HH211 protostellar outflow to assess the jet mass-flux in the form of H2 and investigate the existence of an embedded atomic jet. Methods: We employ archival Spitzer slit-scan observations of the HH211 outflow over 5.2-37 μm obtained with the low resolution IRS modules. Detected molecular and atomic lines are interpreted by means of emission line diagnostics and an existing grid of molecular shock models. The physical properties of the warm gas are compared with those of other molecular jet tracers and to the results of a similar study towards the L1448-C outflow. Results: We detected and mapped the v = 0-0 S(0)-S(7) H2 lines as well as fine-structure lines of S, Fe+, and Si+. The H2 is detected to 5" from the source and is characterized by a “cool” T ~ 300 K and a “warm” T ~ 1000 ± 300 K component, with an extinction AV ~ 8 mag. The amount of cool H2 towards the jet agrees with that estimated from CO assuming fully molecular gas. The warm component is well fitted by C-type shocks with a low beam filling factor ~0.01-0.04 and a mass-flux similar to the cool H2. The fine-structure line emission arises from dense gas with ionization fraction ~0.5-5 × 10-3, and is indicative of dissociative shocks. Line ratios with respect to sulfur indicate that iron and silicon are depleted relative to solar abundances by a factor ~10-50. Conclusions: Spitzer spectral mapping observations reveal for the first time a cool H2 component towards the CO jet of HH211 consistent with the CO material being fully molecular and warm at ≃300 K. These maps detect also for the first time an embedded atomic jet in the HH211 outflow that can be

  8. Polygenic dissection of the bipolar phenotype

    PubMed Central

    Hamshere, M. L.; O’Donovan, M. C.; Jones, I. R.; Jones, L.; Kirov, G.; Green, E. K.; Moskvina, V.; Grozeva, D.; Bass, N.; McQuillin, A.; Gurling, H.; St Clair, D.; Young, A. H.; Ferrier, I. N.; Farmer, A.; McGuffin, P.; Sklar, P.; Purcell, S.; Holmans, P. A.; Owen, M. J.; Craddock, N.

    2011-01-01

    Background Recent data provide strong support for a substantial common polygenic contribution (i.e. many alleles each of small effect) to genetic susceptibility for schizophrenia and overlapping susceptibility for bipolar disorder. Aims To test hypotheses about the relationship between schizophrenia and psychotic types of bipolar disorder. Method Using a polygenic score analysis to test whether schizophrenia polygenic risk alleles, en masse, significantly discriminate between individuals with bipolar disorder with and without psychotic features. The primary sample included 1829 participants with bipolar disorder and the replication sample comprised 506 people with bipolar disorder. Results The subset of participants with Research Diagnostic Criteria schizoaffective bipolar disorder (n = 277) were significantly discriminated from the remaining participants with bipolar disorder (n = 1552) in both the primary (P = 0.00059) and the replication data-sets (P = 0.0070). In contrast, those with psychotic bipolar disorder as a whole were not significantly different from those with non-psychotic bipolar disorder in either data-set. Conclusions Genetic susceptibility influences at least two major domains of psychopathological variation in the schizophrenia–bipolar disorder clinical spectrum: one that relates to expression of a ‘bipolar disorder-like’ phenotype and one that is associated with expression of ‘schizophrenia-like’ psychotic symptoms. PMID:21972277

  9. The management of bipolar disorder.

    PubMed

    Saunders, Kate E A; Geddes, John R

    2016-03-01

    Bipolar disorder is a common mental disorder which is relapsing and remitting in nature. Subsyndromal symptoms are common and associated with poorer outcomes. Management of the disorder can be challenging and depends on the polarity and severity of the mood episode. PMID:26961448

  10. Double heterojunction bipolar phototransistor model

    NASA Astrophysics Data System (ADS)

    Horak, Michal

    2003-07-01

    An analytical mathematical model of the double heterojunction NpN bipolar phototransistor with abrupt heterojunctions in three terminal configuration is presented. The thermionic-filed emission and diffusion of injected carriers is considered and the Ebers-Moll type relations for the collector and emitter current are obtained. Several steady state characteristics of the phototransistor structure are calculated (optical gain, quantum efficiency, responsivity).

  11. Suicidality in Bipolar I Disorder

    ERIC Educational Resources Information Center

    Johnson, Sheri L.; McMurrich, Stephanie L.; Yates, Marisa

    2005-01-01

    People with bipolar disorder are at high suicide risk. The literature suggests that suicidality is predicted by higher symptom severity and less use of pharmacological agents, but few studies have examined the joint contributions of these variables. The present study examines the conjoint contribution of symptom severity and pharmacological…

  12. [Cognitive deficits in bipolar disorder].

    PubMed

    Sachs, Gabriele; Schaffer, Markus; Winklbaur, Bernadette

    2007-01-01

    Bipolar disorders are often associated with cognitive deficits which have an influence on social functioning and the course of the illness. These deficits have an impact on occupational ability and social integration. To date, specific cognitive domains have been found which characterize bipolar affective disorders. However, there is evidence of stable and lasting cognitive impairment in all phases of the disorder, including the remission phase, in the following domains: sustained attention, memory and executive functions (e.g. cognitive flexibility and problem solving). Although their cognitive deficits are comparable the deficits in patients with schizophrenia are more severe than those with bipolar disorder. Recent brain imaging findings indicate structural and functional abnormalities in the cortical and limbic networks of the brain in patients with bipolar disorder compared to healthy controls. Mood stabilizer and atypical antipsychotics may reduce cognitive deficits in certain domains (e.g. executive functions and word fluency) and may have a positive effect on quality of life and social functioning. PMID:17640495

  13. Corrosion resistant metallic bipolar plate

    DOEpatents

    Brady, Michael P.; Schneibel, Joachim H.; Pint, Bruce A.; Maziasz, Philip J.

    2007-05-01

    A corrosion resistant, electrically conductive component such as a bipolar plate for a PEM fuel cell includes 20 55% Cr, balance base metal such as Ni, Fe, or Co, the component having thereon a substantially external, continuous layer of chromium nitride.

  14. A SPECTACULAR OUTFLOW IN AN OBSCURED QUASAR

    SciTech Connect

    Greene, Jenny E.; Zakamska, Nadia L.; Smith, Paul S.

    2012-02-10

    SDSS J1356+1026 is a pair of interacting galaxies at redshift z = 0.123 that hosts a luminous obscured quasar in its northern nucleus. Here we present two long-slit Magellan LDSS-3 spectra that reveal a pair of symmetric {approx}10 kpc size outflows emerging from this nucleus, with observed expansion velocities of {approx}250 km s{sup -1} in projection. We present a kinematic model of these outflows and argue that the deprojected physical velocities of expansion are likely {approx}1000 km s{sup -1} and that the kinetic energy of the expanding shells is likely 10{sup 44-45} erg s{sup -1}, with an absolute minimum of >10{sup 42} erg s{sup -1}. Although a radio counterpart is detected at 1.4 GHz, it is faint enough that the quasar is considered to be radio quiet by all standard criteria, and there is no evidence of extended emission due to radio lobes, whether aged or continuously powered by an ongoing jet. We argue that the likely level of star formation is insufficient to power the observed energetic outflow and that SDSS J1356+1026 is a good case for radio-quiet quasar feedback. In further support of this hypothesis, polarimetric observations show that the direction of quasar illumination is coincident with the direction of the outflow.

  15. The cellular basis of aqueous outflow regulation.

    PubMed

    Francis, B A; Alvarado, J

    1997-04-01

    This review begins with an introduction to the concept of the cellular regulation of aqueous outflow, current methods used for its study, and the cell types that are known to participate in this process. Current research in the field is divided into work on cell properties, cell products and extracellular matrix, cytoskeletal and structural changes, and drug interactions. PMID:10168352

  16. Another piece of the puzzle: The fast H I outflow in Mrk 231

    NASA Astrophysics Data System (ADS)

    Morganti, Raffaella; Veilleux, Sylvain; Oosterloo, Tom; Teng, Stacy H.; Rupke, David

    2016-09-01

    We present the detection, performed with the Westerbork Synthesis Radio Telescope (WSRT) and the Karl Jansky Very Large Array (VLA), of a fast H I 21 cm outflow in the ultra-luminous infrared galaxy Mrk 231. The outflow is observed as shallow H I absorption blueshifted ~1300 km s-1 with respect to the systemic velocity and located against the inner kpc of the radio source. The outflowing gas has an estimated column density between 5 and 15 × 1018Tspin cm-2. We derive the Tspin to lie in the range 400-2000 K and the corresponding H I densities are nHI ~ 10-100 cm-3. Our results complement previous findings and confirm the multiphase nature of the outflow in Mrk 231. Although effects of the interaction between the radio plasma and the surrounding medium cannot be ruled out, the energetics and the lack of a clear kpc-scale jet suggest that the most likely origin of the H I outflow is a wide-angle nuclear wind, as earlier proposed to explain the neutral outflow traced by Na I and molecular gas in this source. Our results suggest that an H I component is present in fast outflows regardless of the acceleration mechanism (wind vs. jet driven) and that it must be connected with common properties of the pre-interaction gas involved. Considering the observed similarity of their column densities, the H I outflow likely represents the inner part of the broad wind identified on larger scales in atomic Na I. The mass outflow rate of the H I outflow (between 8 and 18 M⊙ yr-1) does not appear to be as large as that observed in molecular gas, partly owing to the smaller sizes of the outflowing region sampled by the H I absorption. These characteristics are commonly seen in other cases of outflows driven by the active galactic nucleus (AGN) suggesting that the H I may represent a short intermediate phase in the rapid cooling of the gas. The results further confirm H I as a good tracer for AGN-driven outflows not only in powerful radio sources. We also obtained deeper continuum

  17. Integrated Neurobiology of Bipolar Disorder

    PubMed Central

    Maletic, Vladimir; Raison, Charles

    2014-01-01

    From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity – reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition – limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional “unified field theory” of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial–neuronal interactions. Among these glial elements are microglia – the brain’s primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the hypothalamic–pituitary–adrenal axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway, or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of

  18. Evolution of Mass Outflow in Protostars

    NASA Astrophysics Data System (ADS)

    Watson, Dan M.; Calvet, Nuria P.; Fischer, William J.; Forrest, W. J.; Manoj, P.; Megeath, S. Thomas; Melnick, Gary J.; Najita, Joan; Neufeld, David A.; Sheehan, Patrick D.; Stutz, Amelia M.; Tobin, John J.

    2016-09-01

    We have surveyed 84 Class 0, Class I, and flat-spectrum protostars in mid-infrared [Si ii], [Fe ii], and [S i] line emission, and 11 of these in far-infrared [O i] emission. We use the results to derive their mass outflow rates, {\\dot{M}}w. Thereby we observe a strong correlation of {\\dot{M}}w with bolometric luminosity, and with the inferred mass accretion rates of the central objects, {\\dot{M}}a, which continues through the Class 0 range the trend observed in Class II young stellar objects. Along this trend from large to small mass flow rates, the different classes of young stellar objects lie in the sequence Class 0–Class I/flat-spectrum–Class II, indicating that the trend is an evolutionary sequence in which {\\dot{M}}a and {\\dot{M}}w decrease together with increasing age, while maintaining rough proportionality. The survey results include two that are key tests of magnetocentrifugal outflow-acceleration mechanisms: the distribution of the outflow/accretion branching ratio b={\\dot{M}}w/{\\dot{M}}a, and limits on the distribution of outflow speeds. Neither rules out any of the three leading outflow-acceleration, angular-momentum-ejection mechanisms, but they provide some evidence that disk winds and accretion-powered stellar winds (APSWs) operate in many protostars. An upper edge observed in the branching-ratio distribution is consistent with the upper bound of b = 0.6 found in models of APSWs, and a large fraction (31%) of the sample have a branching ratio sufficiently small that only disk winds, launched on scales as large as several au, have been demonstrated to account for them.

  19. AGN and stellar feedback in star-forming galaxies at redshift 2 : outflows, mass-loading and quenching

    NASA Astrophysics Data System (ADS)

    Roos, O.

    2016-06-01

    Galactic-scale outflows are ubiquitous in observations of star-forming galaxies, up to high redshift. Such galactic outflows are mainly generated by internal sources of feedback: young stars, supernovae and active galactic nuclei (AGNs). Still, the physical origins of such outflows are not well understood, and their main driver is still debated. Up to now, most simulations take into account AGN feedback or stellar feedback but not both, because both phenomena happen on very different spatial and time scales. Most of them also still fail to reproduce all observed parameters from first principles. In this poster, we present the POGO project: Physical Origins of Galactic Outflows. With this suite of 23 simulations, we model AGN and stellar feedback simultaneously based on physical assumptions for the first time at very high resolution (6 to 1.5 pc), and investigate their impact on the outflow parameters of the host-galaxy. Here, we show that AGN and stellar feedback couple non-linearly, and that the mass-loading of the resulting outflow highly depends on the mass of the host, all the more because the coupling can either be positive (small masses) or negative (intermediate masses). Nevertheless, the main driver of the outflow remains the AGN at all masses.

  20. Multiple Outflows in the Giant Eruption of a Massive Star

    NASA Astrophysics Data System (ADS)

    Humphreys, Roberta M.; Martin, John C.; Gordon, Michael S.; Jones, Terry J.

    2016-08-01

    The supernova impostor PSN J09132750+7627410 in NGC 2748 reached a maximum luminosity of ≈‑14 mag. It was quickly realized that it was not a true supernova, but another example of a nonterminal giant eruption. PSN J09132750+7627410 is distinguished by multiple P Cygni absorption minima in the Balmer emission lines that correspond to outflow velocities of ‑400, ‑1100, and ‑1600 km s‑1. Multiple outflows have been observed in only a few other objects. In this paper we describe the evolution of the spectrum and the P Cygni profiles for 3 months past maximum, the post-maximum formation of a cool, dense wind, and the identification of a possible progenitor. One of the possible progenitors is an infrared source. Its pre-eruption spectral energy distribution suggests a bolometric luminosity of ‑8.3 mag and a dust temperature of 780 K. If it is the progenitor, it is above the AGB limit, unlike the intermediate-luminosity red transients. The three P Cygni profiles could be due to ejecta from the current eruption, the wind of the progenitor, or previous mass-loss events. We suggest that they were all formed as part of the same high-mass-loss event and are due to material ejected at different velocities or energies. We also suggest that multiple outflows during giant eruptions may be more common than reported. Based on observations obtained with the Large Binocular Telescope (LBT), an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University and The Research Corporation, on behalf of the University of Notre Dame, University of Minnesota, and University of Virginia.

  1. Tracing the disk, envelope and outflow cavity of VLA1623 with ALMA

    NASA Astrophysics Data System (ADS)

    Murillo, N. M.; Walsh, C.; van Dishoeck, E. F.; Bruderer, S.; Harsono, D.; Lai, S.-P.

    2016-05-01

    Our ALMA Cycle 0 and 2 observations in Band 6 provide tracers of the disk (C18O, 13CO), the envelope (13CO, DCO+) and the outflow and its cavity (12CO, 13CO, c-C3H2) towards VLA1623, a triple non-coeval system in ρ Ophiuchus (d˜120 pc). The observations are combined with simple chemical and physical models. We find differing circumstellar envelope and outflows. VLA1623 appears to not be as chemically rich as other deeply embedded sources.

  2. The IRAS2 and IRAS4 Outflows and Star Formation i NGC 1333

    NASA Technical Reports Server (NTRS)

    Langer, W. D.; Castets, A.; Lefloch, B.

    1996-01-01

    We report the first detection of the western bowshock component from IRAS2 in NGC 1333 along with observations of previously detected shocks and outflow winds from this source and those from IRAS4. We compare the shock and outflow distributions from these two young stellar objects, and the locations of other YSOs, with the overall distribution of the dense molecular gas in the star forming core using high spatial resolution observations of CS (J=2-->1, 3-->2, and 5-->4) emission made with the IRAM 30m antenna.

  3. Numerical Simulations of Radiative Shocked Clumps: Application to the Young Stellar Outflow HH 29

    NASA Astrophysics Data System (ADS)

    Palmer, Jacob Nordin

    Herbig-Haro objects are the nebulous emission regions arising from shocks associated with the bipolar outflows of young stellar objects. Observations of the emission lines of HH objects can reveal properties of these stellar jets, which are associated with star formation, and one tool to study stellar jets and HH objects is computer modeling. AstroBEAR is a 3D magnetohydrodynamic code with adaptive mesh refinement and parallelization capabilities. The goals of this research were (1) to improve the cooling in AstroBEAR and add the ability to create valid emission-line maps for HH objects, and (2) to model a jet overrunning and shocking clumps, and to explore a parameter space that may lead to morphologies like those of HH 29. The results generate emission-line maps with the correct spatial morphology in Halpha and [SII], and begin to map out the regimes (shock velocities, resolution, physical scales) in which the code remains valid.

  4. Detection of a Hot Molecular Disk Around a Massive Protostar Candidate Orion KL Source I

    NASA Astrophysics Data System (ADS)

    Hirota, T.; Kim, M.; Kurono, Y.; Honma, M.

    2015-12-01

    We report results of ALMA cycle 0 observations of the H2O lines at 321 GHz and 336 GHz around a massive protostar candidate Source I in Orion KL. The 336 GHz line is in a vibrationally excited state at the lower state energy of 2939 K. These maps show velocity gradients perpendicular to the bipolar outflow suggesting an existence of a rotating disk. The distribution of the 321 GHz line is found to be similar to that of vibrationally excited SiO masers tracing the base of the outflow emanating from the disk surface. In contrast, the 336 GHz line is emitting from the disk midplane with a diameter of 0.2″ (84 AU) as traced by radio continuum emission. The observed velocity gradient and the spectral profile of the 336 GHz H2O line can be explained by an edge-on ring-like structure with an enclosed mass of >7M⊙ and an excitation temperature of >3000 K. We also investigate the spectral energy distribution of Source I from centimeter to submillimeter wavelengths. Detailed physical and dynamical properties of Source I can be discussed with a spatial scale of smaller than 100 AU.

  5. Diagnosis and treatment of postpartum bipolar depression.

    PubMed

    Kelly, Erin; Sharma, Verinder

    2010-07-01

    The postpartum period is a time of increased risk of new-onset psychiatric illness, hospital admissions and out-patient psychiatric care for new mothers. Research into postpartum mood disorders has focused primarily on major depressive disorder, and has overlooked the study of bipolar disorder, particularly bipolar II disorder and bipolar disorder not otherwise specified. Failure to properly diagnose postpartum bipolar disorder may delay the initiation of appropriate treatment, lead to inappropriate treatment - thereby precipitating (hypo)mania, rapid cycling or a mixed episode - or result in polypharmacy and treatment refractoriness. The most serious consequence, however, is the high risk of infanticide and suicide among women with postpartum bipolar disorder. While no specific screening tools have been validated for postpartum mania or bipolar depression, symptoms of hypomania, atypical depression, a family history of bipolar disorder and a rapid onset of depressive symptoms following delivery may suggest a bipolar diathesis. In the absence of any pharmacological or psychotherapeutic treatments to guide clinical decision-making, it is recommended that the treatment of postpartum bipolar depression follow the same guidelines as the treatment of non-postpartum bipolar depression, using medications that are compatible with lactation. PMID:20586688

  6. Autocapture enhancements: unipolar and bipolar lead compatibility and bipolar pacing capability on bipolar leads.

    PubMed

    Binner, Ludwig; Messenger, John; Sperzel, Johannes; Bondke, Hansjürgen; Vandekerckhove, Yves; Poore, John; Scheiner, Jöerg; Berkhof, Marc; Park, Euljoon; Holmström, Nils; Bornzin, Gene A

    2003-01-01

    Beat-by-beat Autocapture maximizes device longevity by minimizing stimulus amplitude while assuring patient safety. Currently, Autocapture permits use of only bipolar leads. The authors have devised a detection method that operates with unipolar and bipolar leads and covers all pacing and sensing combinations (but bipolar pace and sense simultaneously). This new detection method for unipolar sensing uses the integral of the negative portion of the unipolar evoked response as a robust capture detection feature. When using bipolar leads, the method provides the flexibility of bipolar or unipolar pacing. In this study, unipolar ventricular intracardiac electrograms (EGMs) were recorded in 71 patients, 73.7 +/- 9.9 years of age; 9 with high polarization, 62 with low polarization. High polarization had polished platinum or activated carbon electrodes. Low polarization had TiN, platinized platinum, or IrOx electrodes. The intracardiac EGMs were recorded 544 +/- 796 days after implant. The pacemakers performed an automatic capture threshold test while the intracardiac EGM signals were recorded in a programmer. These digitized signals were saved for off-line analysis. The unipolar evoked response was calculated at up to six (depending on capture threshold) pacing voltages and the polarization integral at 4.5 V and at loss of capture. An automatic calibration algorithm determined if the signal-to-noise ratio was adequate for Autocapture operation. Autocapture was possible with 60 of 62 of the low polarizations, and with 6 of 9 of the high polarizations. The average values form the data collected were: average unipolar evoked response--4.1 +/- 2.1 mV, average peak negative voltage--10.0 +/- 3.7 mV, average polarization 0.3 +/- 0.34 mV, and average signal-to-noise ratio (unipolar evoked response/ polarization) 38 +/- 71. In all cases the algorithm correctly determined the appropriateness of using Autocapture with the electrodes tested and the unipolar evoked response

  7. Nicotine dependence and psychosis in Bipolar disorder and Schizoaffective disorder, Bipolar type.

    PubMed

    Estrada, Elena; Hartz, Sarah M; Tran, Jeffrey; Hilty, Donald M; Sklar, Pamela; Smoller, Jordan W; Pato, Michele T; Pato, Carlos N

    2016-06-01

    Patients with Bipolar disorder smoke more than the general population. Smoking negatively impacts mortality and clinical course in Bipolar disorder patients. Prior studies have shown contradictory results regarding the impact of psychosis on smoking behavior in Bipolar disorder. We analyzed a large sample of Bipolar disorder and Schizoaffective disorder, Bipolar Type patients and predicted those with a history of psychosis would be more likely to be nicotine dependent. Data from subjects and controls were collected from the Genomic Psychiatry Cohort (GPC). Subjects were diagnosed with Bipolar disorder without psychosis (N = 610), Bipolar disorder with psychosis (N = 1544). Participants were classified with or without nicotine dependence. Diagnostic groups were compared to controls (N = 10065) using logistic regression. Among smokers (N = 6157), those with Bipolar disorder had an increased risk of nicotine dependence (OR = 2.5; P < 0.0001). Patients with Bipolar disorder with psychosis were more likely to be dependent than Bipolar disorder patients without psychosis (OR = 1.3; P = 0.03). Schizoaffective disorder, Bipolar Type patients had more risk of nicotine dependence when compared to Bipolar disorder patients with or without psychosis (OR = 1.2; P = 0.02). Bipolar disorder patients experiencing more severity of psychosis have more risk of nicotine dependence. © 2015 Wiley Periodicals, Inc. PMID:26467098

  8. The two-way relationship between ionospheric outflow and the ring current

    NASA Astrophysics Data System (ADS)

    Welling, D. T.; Jordanova, V. K.; Glocer, A.; Toth, G.; Liemohn, M. W.; Weimer, D. R.

    2015-06-01

    It is now well established that the ionosphere, because it acts as a significant source of plasma, plays a critical role in ring current dynamics. However, because the ring current deposits energy into the ionosphere, the inverse may also be true: the ring current can play a critical role in the dynamics of ionospheric outflow. This study uses a set of coupled, first-principles-based numerical models to test the dependence of ionospheric outflow on ring current-driven region 2 field-aligned currents (FACs). A moderate magnetospheric storm event is modeled with the Space Weather Modeling Framework using a global MHD code (Block Adaptive Tree Solar wind Roe-type Upwind Scheme, BATS-R-US), a polar wind model (Polar Wind Outflow Model), and a bounce-averaged kinetic ring current model (ring current atmosphere interaction model with self-consistent magnetic field, RAM-SCB). Initially, each code is two-way coupled to all others except for RAM-SCB, which receives inputs from the other models but is not allowed to feed back pressure into the MHD model. The simulation is repeated with pressure coupling activated, which drives strong pressure gradients and region 2 FACs in BATS-R-US. It is found that the region 2 FACs increase heavy ion outflow by up to 6 times over the noncoupled results. The additional outflow further energizes the ring current, establishing an ionosphere-magnetosphere mass feedback loop. This study further demonstrates that ionospheric outflow is not merely a plasma source for the magnetosphere but an integral part in the nonlinear ionosphere-magnetosphere-ring current system.

  9. The two-way relationship between ionospheric outflow and the ring current

    SciTech Connect

    Welling, Daniel T.; Jordanova, Vania Koleva; Glocer, Alex; Toth, Gabor; Liemohn, Michael W.; Weimer, Dan R.

    2015-06-01

    It is now well established that the ionosphere, because it acts as a significant source of plasma, plays a critical role in ring current dynamics. However, because the ring current deposits energy into the ionosphere, the inverse may also be true: the ring current can play a critical role in the dynamics of ionospheric outflow. This study uses a set of coupled, first-principles-based numerical models to test the dependence of ionospheric outflow on ring current-driven region 2 field-aligned currents (FACs). A moderate magnetospheric storm event is modeled with the Space Weather Modeling Framework using a global MHD code (Block Adaptive Tree Solar wind Roe-type Upwind Scheme, BATS-R-US), a polar wind model (Polar Wind Outflow Model), and a bounce-averaged kinetic ring current model (ring current atmosphere interaction model with self-consistent magnetic field, RAM-SCB). Initially, each code is two-way coupled to all others except for RAM-SCB, which receives inputs from the other models but is not allowed to feed back pressure into the MHD model. The simulation is repeated with pressure coupling activated, which drives strong pressure gradients and region 2 FACs in BATS-R-US. It is found that the region 2 FACs increase heavy ion outflow by up to 6 times over the non-coupled results. The additional outflow further energizes the ring current, establishing an ionosphere-magnetosphere mass feedback loop. This study further demonstrates that ionospheric outflow is not merely a plasma source for the magnetosphere but an integral part in the nonlinear ionosphere-magnetosphere-ring current system.

  10. The two-way relationship between ionospheric outflow and the ring current

    DOE PAGESBeta

    Welling, Daniel T.; Jordanova, Vania Koleva; Glocer, Alex; Toth, Gabor; Liemohn, Michael W.; Weimer, Dan R.

    2015-06-01

    It is now well established that the ionosphere, because it acts as a significant source of plasma, plays a critical role in ring current dynamics. However, because the ring current deposits energy into the ionosphere, the inverse may also be true: the ring current can play a critical role in the dynamics of ionospheric outflow. This study uses a set of coupled, first-principles-based numerical models to test the dependence of ionospheric outflow on ring current-driven region 2 field-aligned currents (FACs). A moderate magnetospheric storm event is modeled with the Space Weather Modeling Framework using a global MHD code (Block Adaptivemore » Tree Solar wind Roe-type Upwind Scheme, BATS-R-US), a polar wind model (Polar Wind Outflow Model), and a bounce-averaged kinetic ring current model (ring current atmosphere interaction model with self-consistent magnetic field, RAM-SCB). Initially, each code is two-way coupled to all others except for RAM-SCB, which receives inputs from the other models but is not allowed to feed back pressure into the MHD model. The simulation is repeated with pressure coupling activated, which drives strong pressure gradients and region 2 FACs in BATS-R-US. It is found that the region 2 FACs increase heavy ion outflow by up to 6 times over the non-coupled results. The additional outflow further energizes the ring current, establishing an ionosphere-magnetosphere mass feedback loop. This study further demonstrates that ionospheric outflow is not merely a plasma source for the magnetosphere but an integral part in the nonlinear ionosphere-magnetosphere-ring current system.« less

  11. Broad [C II] Line Wings as Tracer of Molecular and Multi-phase Outflows in Infrared Bright Galaxies

    NASA Astrophysics Data System (ADS)

    Janssen, A. W.; Christopher, N.; Sturm, E.; Veilleux, S.; Contursi, A.; González-Alfonso, E.; Fischer, J.; Davies, R.; Verma, A.; Graciá-Carpio, J.; Genzel, R.; Lutz, D.; Sternberg, A.; Tacconi, L.; Burtscher, L.; Poglitsch, A.

    2016-05-01

    We report a tentative correlation between the outflow characteristics derived from OH absorption at 119 μm and [C ii] emission at 158 μm in a sample of 22 local and bright ultraluminous infrared galaxies (ULIRGs). For this sample, we investigate whether [C ii] broad wings are a good tracer of molecular outflows, and how the two tracers are connected. Fourteen objects in our sample have a broad wing component as traced by [C ii], and all of these also show OH119 absorption indicative of an outflow (in one case an inflow). The other eight cases, where no broad [C ii] component was found, are predominantly objects with no OH outflow or a low-velocity (≤100 km s‑1) OH outflow. The FWHM of the broad [C ii] component shows a trend with the OH119 blueshifted velocity, although with significant scatter. Moreover, and despite large uncertainties, the outflow masses derived from OH and broad [C ii] show a 1:1 relation. The main conclusion is therefore that broad [C ii] wings can be used to trace molecular outflows. This may be particularly relevant at high redshift, where the usual tracers of molecular gas (like low-J CO lines) become hard to observe. Additionally, observations of blueshifted Na i D λλ 5890, 5896 absorption are available for 10 of our sources. Outflow velocities of Na i D show a trend with OH velocity and broad [C ii] FWHM. These observations suggest that the atomic and molecular gas phases of the outflow are connected.

  12. Accretion, winds and outflows in young stars

    NASA Astrophysics Data System (ADS)

    Günther, H. M.

    2013-02-01

    Young stars and planetary systems form in molecular clouds. After the initial radial infall an accretion disk develops. For classical T Tauri stars (CTTS, F-K type precursors) the accretion disk does not reach down to the central star, but it is truncated near the co-rotation radius by the stellar magnetic field. The inner edge of the disk is ionized by the stellar radiation, so that the accretion stream is funneled along the magnetic field lines. On the stellar surface an accretion shock develops, which is observed over a wide wavelength range as X-ray emission, UV excess, optical veiling and optical and IR emission lines. Some of the accretion tracers, e.g. Hα, can be calibrated to measure the accretion rate. This accretion process is variable on time scales of hours to years due to changing accretion rates, stellar rotation and reconfiguration of the magnetic field. Furthermore, many (if not all) accreting systems also drive strong outflows which are ultimately powered by accretion. However, the exact driving mechanism is still unclear. Several components could contribute to the outflows: slow, wide-angle disk winds, X-winds launched close to the inner disk rim, and thermally driven stellar winds. In any case, the outflows contain material of very different temperatures and speeds. The disk wind is cool and can have a molecular component with just a few tens of km s-1, while the central component of the outflow can reach a few 100 km s-1. In some cases the inner part of the outflow is collimated to a small-angle jet. These jets have an onion-like structure, where the inner components are consecutively hotter and faster. The jets can contain working surfaces, which show up as Herbig-Haro knots. Accretion and outflows in the CTTS phase do not only determine stellar parameters like the rotation rate on the main-sequence, they also can have a profound impact on the environment of young stars. This review concentrates on CTTS in near-by star forming regions where

  13. The Nature and Frequency of Outflows from Stars in the Central Orion Nebula Cluster

    NASA Astrophysics Data System (ADS)

    O'Dell, C. R.; Ferland, G. J.; Henney, W. J.; Peimbert, M.; García-Díaz, Ma. T.; Rubin, Robert H.

    2015-10-01

    Recent Hubble Space Telescope images have allowed the determination with unprecedented accuracy of motions and changes of shocks within the inner Orion Nebula. These originate from collimated outflows from very young stars, some within the ionized portion of the nebula and others within the host molecular cloud. We have doubled the number of Herbig-Haro objects known within the inner Orion Nebula. We find that the best-known Herbig-Haro shocks originate from relatively few stars, with the optically visible X-ray source COUP 666 driving many of them. While some isolated shocks are driven by single collimated outflows, many groups of shocks are the result of a single stellar source having jets oriented in multiple directions at similar times. This explains the feature that shocks aligned in opposite directions in the plane of the sky are usually blueshifted because the redshifted outflows pass into the optically thick photon-dominated region behind the nebula. There are two regions from which optical outflows originate for which there are no candidate sources in the SIMBAD database. Based on observations at the San Pedro Martir Observatory operated by the Universidad Nacional Autónoma de México.

  14. Tracing Carina's protostellar jets to the source with WFC3-IR

    NASA Astrophysics Data System (ADS)

    Smith, Nathan

    2010-09-01

    Based on a recent H-alpha imaging survey of the Carina Nebula with ACS, we discovered 39 new Herbig-Haro {HH} jets marking the bipolar outflows from newly formed low-mass stars. This provides a valuable sample of jets that are all at the same distance, allowing us to study the relationship between protostars and their outflows where nearby massive stars are shredding the molecular cloud as new stars are forming. Carina has been studied extensively with Spitzer and Chandra, providing IR spectral energy distributions and X-ray luminosities for all detectable sources in the field. However, 29 of the jets seen at visual wavelengths emerge from opaque clouds or dark globules seen in silhouette against the bright background H II region, so the protostellar driving sources are still embedded in their natal clouds and are not identifiable in optical images. This makes the identification of the driving sources in lower resolution Spitzer and Chandra images ambiguous. Three of these jets {HH666, HH901, and HH902} have already been imaged with WFC3 as ERO targets after the servicing mission, demonstrating that near-IR [Fe II] emission lines in the F126N and F164N filters provide an excellent way to trace the jet emission back into the cloud and to thereby identify which embedded star is driving the outflow. Here we propose to obtain WFC3-IR images of [Fe II] emission from the remaining embedded jets in order to link the jets to the protostars that launch them. This will then permit a comparison of the jet properties to protostar properties for the full sample. Additionally, the flux ratio of these two [Fe II] lines will probe the spatially dependent extinction through the cloud all the way back to the source, providing a map of the density structure in the protostar's extended circumstellar envelope.

  15. The Shaping of Circumstellar Envelopes by Outflow and Infall Motions

    NASA Astrophysics Data System (ADS)

    Arce, H. G.; Calvet, N.; Sargent, A.

    2004-12-01

    In this study, we combine the complementary information obtained from Owens Valley Radio Observatory (OVRO) millimeter array observations of molecular gas around protostars and HST (WFPC2 and NICMOS) archival images of reflection nebulae to obtain the best information available on the physical and dynamical properties of infalling circumstellar envelopes and the outflow-envelope interaction. The HST images of protostellar nebulae probe the dust component of the envelope, and are the best tracers of the geometry of the cavities in the envelope down to regions very close to the central source. The interferometric molecular line observations from OVRO probe the gas component, which constitutes most of the mass, and provide kinematic information that directly reflects the energetics and directions of the outflows, and the distribution of the infalling gas. We plan to analyze the information provided by these two sets of data using scattered light models of protostellar envelopes of different geometries in which cavities due to infall and/or winds with different morphologies and strength have been carved. Preliminary results show that the cavities traced by nebular emission are most likely produced by the interaction of wide-angle protostellar winds and the stellar envelope, rather than by infall of the envelope material onto the forming star. Support for this study is provided in part by an STScI HST Archival grant (HST-AR-09909.01-A). HGA is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-0401568.

  16. Outflows in infrared-luminous galaxies: Absorption-line spectroscopy of starbursts and AGN

    NASA Astrophysics Data System (ADS)

    Rupke, David S.

    Large-scale galactic outflows, better known as superwinds, are driven by the powerful energy reservoirs in star forming and active galaxies. They play a significant role in galaxy formation, galaxy evolution, and the evolution of the intergalactic medium. We have performed a survey of over 100 infrared-luminous galaxies in order to address the exact frequency with which they occur in different galaxy types, the dependence of their properties on those of their host galaxies, and their properties in the most luminous starburst and active galaxies. Most of our sample consists of ultraluminous infrared galaxies (ULIRGs), and we use moderate- resolution spectroscopy of the Na I D interstellar absorption feature (which directly probes the neutral gas phase). We find superwinds in the majority of these galaxies at typical maximum, deprojected velocities of 500 700 km s-1. The detection rate increases with star formation rate (SFR) in starbursts, while the mass outflow rate appears constant with SFR, contrary to theoretical expectations. The resulting mass entrainment efficiencies in ULIRGs are quite low, of order a few percent of the star formation rate. There is some dependence of outflow velocity on host galaxy properties; the outflow velocities in LINERs are higher than those in H II galaxies, and the highest column density gas in each galaxy may have an upper envelope in velocity that increases with SFR. Outflows in most galaxies hosting a dominant AGN have very similar properties to those in starbursts, so discerning their power source is difficult. The velocities in Seyfert 2 outflows may be slightly higher than those in starbursts, and the fraction of neutral gas escaping Seyfert 2s is higher than that in starbursts (˜50% vs. ≲ 20%). The outflows in our Seyfert 1 galaxies have extreme velocities of up to ˜104 km s-1, and two of three Seyfert is with outflows possess broad absorption lines. Finally, we find that spectroscopy of a few galaxies at very high

  17. Compact objects at the heart of outflows in large and small systems

    NASA Astrophysics Data System (ADS)

    Sell, Paul Harrison

    2013-12-01

    This thesis focuses on studying and assessing high-energy feedback generated by both stellar mass and supermassive compact objects. From these two perspectives, I help bridge the gap in understanding how jets and winds can transform their much larger environments in thousands to millions of years, astronomically short timescales. I have acquired X-ray and optical data that aim to elucidate the role these objects play in powering parsec-scale shockwaves in the ISM and in driving kiloparsec-scale outflows in galaxies. I present Chandra X-ray imaging, Hubble Space Telescope imaging, and WIYN Hydra multi-object optical spectroscopic observations. The data reveal the morphologies of the systems and constrain on a range of interesting parameters: power, outflow velocity, density, accretion efficiency, and timescale. My analysis provides perspective on the importance of black holes, both large and small, and neutron stars for driving outflows into the interstellar and intergalactic medium. On kiloparsec scales, I explore the nature of what appear to be merging or recently merging post-starburst galaxies with very high-velocity winds. This work is part of a multiwavelength effort to characterize the niche these galaxies fill in the larger scheme of galaxy evolution. My focus is on the accretion activity of the coalescing supermassive black holes in their cores. This work leads us to compare the relative importance of a massive starburst to the supermassive black holes in the cores of the galaxies. On parsec scales, I present case studies of two prominent microquasars, Galactic X-ray binaries with jets, Circinus X-1 and Cygnus X-1. In the case of Circinus X-1, I present very deep follow-up observations of parsec-scale shock plumes driven by a powerful, bipolar jet. In the case of Cygnus X-1, I present follow-up observations to probe a recently discovered outflow near the binary. I calculate robust, physically motivated limits on the total power needed to drive the outflows

  18. Identifying Potential Regions of Copy Number Variation for Bipolar Disorder

    PubMed Central

    Chen, Yi-Hsuan; Lu, Ru-Band; Hung, Hung; Kuo, Po-Hsiu

    2014-01-01

    Bipolar disorder is a complex psychiatric disorder with high heritability, but its genetic determinants are still largely unknown. Copy number variation (CNV) is one of the sources to explain part of the heritability. However, it is a challenge to estimate discrete values of the copy numbers using continuous signals calling from a set of markers, and to simultaneously perform association testing between CNVs and phenotypic outcomes. The goal of the present study is to perform a series of data filtering and analysis procedures using a DNA pooling strategy to identify potential CNV regions that are related to bipolar disorder. A total of 200 normal controls and 200 clinically diagnosed bipolar patients were recruited in this study, and were randomly divided into eight control and eight case pools. Genome-wide genotyping was employed using Illumina Human Omni1-Quad array with approximately one million markers for CNV calling. We aimed at setting a series of criteria to filter out the signal noise of marker data and to reduce the chance of false-positive findings for CNV regions. We first defined CNV regions for each pool. Potential CNV regions were reported based on the different patterns of CNV status between cases and controls. Genes that were mapped into the potential CNV regions were examined with association testing, Gene Ontology enrichment analysis, and checked with existing literature for their associations with bipolar disorder. We reported several CNV regions that are related to bipolar disorder. Two CNV regions on chromosome 11 and 22 showed significant signal differences between cases and controls (p < 0.05). Another five CNV regions on chromosome 6, 9, and 19 were overlapped with results in previous CNV studies. Experimental validation of two CNV regions lent some support to our reported findings. Further experimental and replication studies could be designed for these selected regions.

  19. Langevin approach to noise modelling of bipolar microwave transistors

    NASA Astrophysics Data System (ADS)

    Patti, F.; Miceli, V.; Spagnolo, B.

    2000-04-01

    We present a new approach to study the complete stochastic properties of fluctuations of the output current of microwave transistors. We obtain the π-hybrid model of bipolar microwave transistors with the noise internal sources starting from experimental on-wafer measurements of the scattering and noise parameters. We derive the stochastic differential equations of the Giacoletto model for different loads and source admittances. We give the analytical temporal behavior of the second moment of the output current, assuming particular given correlation functions between the internal noise sources.

  20. Electron-positron outflow from black holes.

    PubMed

    van Putten, M H

    2000-04-24

    Cosmological gamma-ray bursts (GRBs) appear as the brightest transient phenomena in the Universe. The nature of their central engine is a missing link in the theory of fireballs to stellar mass progenitors, and may be associated with low mass black holes. In contact with an external magnetic field B, black hole spin produces a gravitational potential on the wave function of charged particles. We show that a rapidly rotating black hole of mass M produces outflow from initially electrostatic equilibrium with normalized isotropic emission approximately 10(48)(B/B(c))(2)(M/7M)(2)sin (2) theta erg/s, where B(c) = 4.4x10(13) G. The half-opening angle satisfies theta >or = square root[B(c)/3B]. The outflow proposed as input to GRB fireball models. PMID:11019197

  1. Molecular emission in chemically active protostellar outflows

    NASA Astrophysics Data System (ADS)

    Lefloch, B.

    2011-12-01

    Protostellar outflows play an important role in the dynamical and chemical evolution of cloud through shocks. The Herschel Space Observatory (HSO) brings new insight both on the molecular content and the physical conditions in protostellar shocks through high spectral and angular resolution studies of the emission of major gas cooling agents and hydrides. The Herschel/CHESS key-program is carrying out an in depth study of the prototypical shock region L1157-B1. Analysis of the line profiles detected allows to constrain the formation/destruction route of various molecular species, in relation with the predictions of MHD shock models. The Herschel/WISH key-program investigates the properties and origin of water emission in a broad sample of protostellar outflows and envelopes. Implications of the first results for future studies on mass-loss phenomena are discussed.

  2. Hepatic venous outflow obstruction: Three similar syndromes

    PubMed Central

    Bayraktar, Ulas Darda; Seren, Soley; Bayraktar, Yusuf

    2007-01-01

    Our goal is to provide a detailed review of veno-occlusive disease (VOD), Budd-Chiari syndrome (BCS), and congestive hepatopathy (CH), all of which results in hepatic venous outflow obstruction. This is the first article in which all three syndromes have been reviewed, enabling the reader to compare the characteristics of these disorders. The histological findings in VOD, BCS, and CH are almost identical: sinusoidal congestion and cell necrosis mostly in perivenular areas of hepatic acini which eventually leads to bridging fibrosis between adjacent central veins. Tender hepatomegaly with jaundice and ascites is common to all three conditions. However, the clinical presentation depends mostly on the extent and rapidity of the outflow obstruction. Although the etiology and treatment are completely different in VOD, BCS, and CH; the similarities in clinical manifestations and liver histology may suggest a common mechanism of hepatic injury and adaptation in response to increased sinusoidal pressure. PMID:17461490

  3. Example of reduced turbulence during thunderstorm outflow

    SciTech Connect

    Bowen, B.M.

    1996-06-01

    This research note describes the effects of a gust front passage resulting from a thunderstorm outflow on wind, turbulence, and other basic meteorological variables in northern Mew Mexico. The purpose of this note is to explain how a thunderstorm outflow can greatly reduce horizontal and vertical turbulence and produce strong winds, thereby promoting the rapid transport of elevated pollutant concentrations. Another goal is to demonstrate the usefulness of a sodar in combination with a tower to provide data for dispersion and transport calculations during an emergency response. Hopefully, this note will motivate other researchers to analyze and document the effects of thunderstorms on turbulence and dispersion by routine monitoring or by experimentation. 12 refs., 3 figs., 1 tab.

  4. STIS Observations of the Disk and Outflow of the Herbig Ae Star HD163296

    NASA Technical Reports Server (NTRS)

    Kimble, Randy; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Coronagraphic imaging with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope reveals a approx. 450 AU radius circumstellar disk around the Herbig Ae star HDI63296. The disk includes an annulus of reduced scattering at 325 AU and exhibits a flat trend of surface brightness in to 180-222 AU, consistent with a cleared central zone. The disk is accompanied by a chain of nebulosities ("knots") oriented roughly perpendicular to the disk. Followup spectroscopy in the visible and the far ultraviolet confirms the Herbig-Haro nature of the observed knots. The FUV data in particular reveal the presence of a collimated, bipolar outflow, with a blue-shifted Lyman alpha jet that can be traced to within 0.06 arcseconds (7.3 AU) of HD163296 and a red-shifted Lyman alpha component that may be due to infall or to a poorly collimated wind. If the estimated age of this system is correct, these data indicate that protostellar outflows may last up to 10 times longer than previously believed.

  5. [Psychopharmacological treatment of bipolar disease].

    PubMed

    Licht, Rasmus W; Vestergaard, Per

    2002-05-01

    This paper gives an update on the psychopharmacological treatment of bipolar disorder. The antimanic efficacy of lithium is well documented. The same applies to valproate, which is also efficacious in mixed mania. Conventional antipsychotics act fast in mania and do not require blood tests, but they have considerable neurological side effects. The newer antipsychotics, olanzapine, risperidone, and ziprasidone, have also been shown to have antimanic efficacy. Clozapine is extremely effective, also when other treatment fails. For the treatment of bipolar depression, lithium, lamotrigine, and antidepressants all seem to work, but antidepressants may sometimes precipitate mania or worsen the course of illness. For prophylaxis, lithium is still to be considered the first drug of choice. However, for several reasons, for instance treatment failure or side effects, long-term treatment with antiepileptics may often be necessary. Among the antiepileptics, carbamazepine, valproate, and lamotrigine are the best studied. PMID:12025705

  6. [Poststroke-bipolar affective disorder].

    PubMed

    Bengesser, S A; Wurm, W E; Lackner, N; Birner, A; Reininghaus, B; Kapfhammer, H-P; Reininghaus, E

    2013-08-01

    A few weeks after suffering from a basal ganglia infarction (globus pallidus) with left-sided hemiplegia, a 23-year-old woman exhibited for the first time a pronounced mania with self-endangerment. The use of oral contraceptives was the only determinable risk factor. During the further course, the mother also developed a depressive disorder. Thus a certain genetic predisposition for affective disorders may be relevant, although this would not explain the outbreak by itself. An association between the right-sided basal ganglia infarction and the occurrence of a bipolar affective disorder has been described in the literature. Vascular or, respectively, inflammatory risk factors in synopsis with the aetiopathogenesis of bipolar affective disorders are also discussed in depth in this case report. PMID:23939559

  7. [Psychosis and bipolarity].

    PubMed

    Lagomarsino, Alejandro

    2002-01-01

    Since Kraepelin s pioneering differentiation, schizophrenia and manic-depressive psychosis have been considered distinct diseases. Research findings from different sources have found several similarities between these two disorders, casting doubts on Kraepelin s distinction. The current concept of spectrum seems to be more adequate to explain the relations between them. At the same time, a group of medicines, atypical antipsychotics, have shown interesting properties for the treatment of both affective and psychotic symptomatology. PMID:12122425

  8. THE OUTFLOWING WIND OF V1057 CYGNI

    SciTech Connect

    Herbig, G. H.

    2009-08-15

    In 1970-1971, V1057 Cyg rose from about m {sub pg} {approx} 16 to a peak near 10.5 mag. It has subsequently faded to about B = 15, and although it appeared to be a T Tauri star (TTS) before the outburst, it now resembles a rather peculiar rapidly rotating G-type supergiant. Before the outburst, it showed unmistakable evidence of high-velocity outflow (by the suppression of emission Ca II {lambda}3968 by the P Cyg absorption component of H{epsilon} {lambda}3970). Such outflow absorptions are currently found at many strong lines (H{alpha}, Na I D{sub 1,2}, K I {lambda}{lambda}7664, 7698, Ca II {lambda}{lambda}8498, 8662, ...). The same phenomenon has since been observed in a number of other FUors near maximum light, suggesting that it is a FUor characteristic that clearly differs from the outflows found in TTSs. The Li I resonance line at 6707 A is relatively weak, and on high-resolution spectra obtained between 1997 and 2008 showed variable absorption structure on its shortward side that probably represents wind structure that is lost in the stronger lines. In addition, a narrow emission line at 6707 A persists throughout the series and is the counterpart of the sharp emission lines that occur near the centers of many of the broad stellar absorption lines (v sin i = 55 km s{sup -1}) and that were responsible for the line-splitting phenomenon formerly regarded as evidence of a Keplerian disk. Given the evidence of a quasi-permanent outflow at V1057 Cyg, the hypothesis is advanced that a FUor outburst may be the result of a rapidly rotating TTS having contracted to a point of rotational instability, at which time it sheds enough material and angular momentum to resume contraction, until the next such event.

  9. Shaping the outflows of evolved stars

    NASA Astrophysics Data System (ADS)

    Mohamed, Shazrene

    2015-08-01

    Both hot and cool evolved stars, e.g., red (super)giants and Wolf-Rayet stars, lose copious amounts of mass, momentum and mechanical energy through powerful, dense stellar winds. The interaction of these outflows with their surroundings results in highly structured and complex circumstellar environments, often featuring knots, arcs, shells and spirals. Recent improvements in computational power and techniques have led to the development of detailed, multi-dimensional simulations that have given new insight into the origin of these structures, and better understanding of the physical mechanisms driving their formation. In this talk, I will discuss three of the main mechanisms that shape the outflows of evolved stars:- interaction with the interstellar medium (ISM), i.e., wind-ISM interactions- interaction with a stellar wind, either from a previous phase of evolution or the wind from a companion star, i.e., wind-wind interactions- and interaction with a companion star that has a weak or insignicant outflow (e.g., a compact companion such as a neutron star or black hole), i.e., wind-companion interactions.I will also highlight the broader implications and impact of these stellar wind interactions for other phenomena, e.g, for symbiotic and X-ray binaries, supernovae and Gamma-ray bursts.

  10. Magnetohydrodynamic simulations of outflows from accretion disks

    NASA Technical Reports Server (NTRS)

    Ustyugova, G. V.; Koldoba, A. V.; Romanova, M. M.; Chechetkin, V. M.; Lovelace, R. V. E.

    1995-01-01

    Magnetohydrodynamic simulations have been made of the formation of outflows from a Keplerian disk threaded by a magnetic field. The disk is treated as a boundary condition, where matter is ejected with Keplerian azimuthal speed and poloidal speed less than the slow magnetosonic velocity, and where boundary conditions on the magnetic field correspond to a highly conducting disk. Initially, the space above the disk, the corona, is filled with high specific entropy plasma in thermal equilibrium in the gravitational potential of the central object. The initial magnetic field is poloidal and is represented by a superposition of monopoles located below the plane of the disk. The rotation of the disk twists the initial poloidal magnetic field, and this twist propagates into the corona pushing and collimating matter into jetlike outflow in a cylindrical region. Matter outflowing from the disk flows and accelerates in the z-direction owing to both the magnetic and pressure gradient forces. The flow accelerates through the slow magnetosonic and Alfven surfaces and at larger distances through the fast magnetosonic surface. The flow velocity of the jet is approximately parallel to the z-axis, and the collimation results from the pinching force of the toroidal magnetic field. For a nonrotating disk no collimation is observed.

  11. Major Ups and Downs: Bipolar Disorder Brings Extreme Mood Swings

    MedlinePlus

    ... our exit disclaimer . Subscribe Major Ups and Downs Bipolar Disorder Brings Extreme Mood Swings Most people feel happy ... Strike Out Stroke Wise Choices Links Dealing with Bipolar Disorder If you have bipolar disorder, get treatment and ...

  12. Course of Subthreshold Bipolar Disorder in Youth: Diagnostic Progression from Bipolar Disorder Not Otherwise Specified

    ERIC Educational Resources Information Center

    Axelson, David A.; Birmaher, Boris; Strober, Michael A.; Goldstein, Benjamin I.; Ha, Wonho; Gill, Mary Kay; Goldstein, Tina R.; Yen, Shirley; Hower, Heather; Hunt, Jeffrey I.; Liao, Fangzi; Iyengar, Satish; Dickstein, Daniel; Kim, Eunice; Ryan, Neal D.; Frankel, Erica; Keller, Martin B.

    2011-01-01

    Objective: To determine the rate of diagnostic conversion from an operationalized diagnosis of bipolar disorder not otherwise specified (BP-NOS) to bipolar I disorder (BP-I) or bipolar II disorder (BP-II) in youth over prospective follow-up and to identify factors associated with conversion. Method: Subjects were 140 children and adolescents…

  13. BAL OUTFLOW CONTRIBUTION TO AGN FEEDBACK: FREQUENCY OF S IV OUTFLOWS IN THE SDSS

    SciTech Connect

    Dunn, Jay P.; Arav, Nahum; Laughlin, Courtney; Edmonds, Doug; Aoki, Kentaro; Wilkins, Ashlee; Bautista, Manuel E-mail: arav@vt.edu E-mail: kentaro.aoki@hawaiiantel.net E-mail: manuel.bautista@wmich.edu

    2012-05-10

    We present a study of broad absorption line (BAL) quasar outflows that show S IV {lambda}1063 and S IV* {lambda}1073 troughs. The fractional abundances of S IV and C IV peak at similar value of the ionization parameter, implying that they arise from the same physical component of the outflow. Detection of the S IV* troughs will allow us to determine the distance to this gas with higher resolution and higher signal-to-noise spectra, therefore providing the distance and energetics of the ubiquitous C IV BAL outflows. In our bright sample of 156 SDSS quasars, 14% show C IV and 1.9% S IV troughs, which are consistent with a fainter magnitude sample with twice as many objects. One object in the fainter sample shows evidence of a broad S IV trough without any significant trough present from the excited state line, which implies that this outflow could be at a distance of several kpc. Given the fractions of C IV and S IV, we establish firm limits on the global covering factor on S IV that ranges from 2.8% to 21% (allowing for the k-correction). Comparison of the expected optical depth for these ions with their detected percentage suggests that these species arise from common outflows with a covering factor closer to the latter.

  14. Recent progress in understanding pediatric bipolar disorder.

    PubMed

    Goldstein, Benjamin I

    2012-04-01

    Bipolar disorder is one of the most severe psychiatric illnesses, particularly when onset occurs during childhood or adolescence. With recent empirical evidence, questions regarding the existence of bipolar disorder among children and adolescents have given way to questions regarding prevalence. There are substantial risks inherent in misapplying diagnoses and treatments of bipolar disorder when not warranted and in withholding these diagnoses and treatments when they are warranted. As with adults, the course of bipolar disorder among children and adolescents diagnosed using unmodified diagnostic criteria is characterized by recovery and recurrence, functional impairment, suicidality, and high rates of comorbid psychiatric and medical problems. Discrepancies between increasing billing diagnoses and a stable epidemiologic prevalence of bipolar disorder suggest the possibility that diagnostic criteria are not being systematically applied in some clinical settings. Introducing new diagnoses may exacerbate rather than mitigate concerns regarding misdiagnosis and excessive use of mood-stabilizing medications. Several medications, particularly second-generation antipsychotics, are efficacious for treating acute manic episodes of bipolar I disorder. However, less is known regarding the treatment of other mood states and subtypes of bipolar disorder. Psychosocial treatments provide a forum in which to educate children and families regarding bipolar disorder and its treatment, and may be especially beneficial for reducing depressive symptoms. Offspring of parents with bipolar disorder are at increased risk of developing the illness, as are youth with major depressive disorder and certain psychiatric comorbidities. Preliminary findings regarding biomarkers offer hope that, in the future, these biomarkers may inform diagnostic and treatment decisions. PMID:22213607

  15. Distinctions between bipolar and unipolar depression

    PubMed Central

    Cuellar, Amy K.; Johnson, Sheri L.; Winters, Ray

    2010-01-01

    This is a review of the studies comparing unipolar and bipolar depression, with focus on the course, symptomatology, neurobiology, and psychosocial literatures. These are reviewed with one question in mind: does the evidence support diagnosing bipolar and unipolar depressions as the same disorder or different? The current nomenclature of bipolar and unipolar disorders has resulted in research that compares these disorders as a whole, without considering depression separately from mania within bipolar disorder. Future research should investigate two broad categories of depression and mania as separate disease processes that are highly comorbid. PMID:15792852

  16. DMFC bipolar material and new processing for μDMFC microchannel

    NASA Astrophysics Data System (ADS)

    Yin, Bifeng; Guan, Tao; Wang, Yun

    2010-10-01

    DMFC (Direct Methanol Fuel Cell) is attractive as green energy with the characteristics of high energy conversion rate, lower carbon and emission, eco-friendly alternative energy. In DMFC, bipolar plate is one key component because of its high performance requirements, the bipolar plate nearly always makes about 60% contribution to the cost of all fuel cell, seriously affected the commercialization progress of DMFC. Furthermore, the flow channel design and arrangement in bipolar plate has a great influence on water and heat management, distribution of reactants and smooth resultant discharge. So the DMFC bipolar plate material and flow channel processing technique obtains more concerns. After introducing the bipolar plate structure and its functions, it points out that the bipolar plate material nowadays mainly involves the graphite materials, metals and composite. Then the corresponding preparation method, advantages and disadvantages of these three kinds of bipolar plate materials are analyzed. With the rapid development of Micro and Nano-technology and the demand for electricity supply of MEMS (Micro Electro Mechanical systems, micro-energy sources have been the focus, resulting in the miniaturization DMFC (μ DMFC). As the micro-bipolar plates has to survive the severe rugged working environment, such as high temperature, deep-etching, multi-field and alternating pressure), which challenges the material selection, flow channel configuration, processing method and precision. Therefore, hard-to-deform material such as titanium alloy is the preferred material for micro-bipolar plate. However, the new processing method has to be initialized for hard-to-deform material. This paper introduces the traditional and advanced processing methods of μDMFC bipolar plate. The existing problems of the DMFC bipolar plate material selection and processing are analyzed. We initialized one new technique that combines the laser-assisted heating method and micro die-pressing. The

  17. Quasar feedback revealed by giant molecular outflows

    NASA Astrophysics Data System (ADS)

    Feruglio, C.; Maiolino, R.; Piconcelli, E.; Menci, N.; Aussel, H.; Lamastra, A.; Fiore, F.

    2010-07-01

    In the standard scenario for galaxy evolution young star-forming galaxies transform into red bulge-dominated spheroids, where star formation has been quenched. To explain this transformation, a strong negative feedback generated by accretion onto a central super-massive black hole is often invoked. The depletion of gas resulting from quasar-driven outflows should eventually stop star-formation across the host galaxy and lead the black hole to “suicide” by starvation. Direct observational evidence for a major quasar feedback onto the host galaxy is still missing, because outflows previously observed in quasars are generally associated with the ionized component of the gas, which only accounts for a minor fraction of the total gas content, and typically occurrs in the central regions. We used the IRAM PdB Interferometer to observe the CO(1-0) transition in Mrk 231, the closest quasar known. Thanks to the wide band we detected broad wings of the CO line, with velocities of up to 750 km s-1 and spatially resolved on the kpc scale. These broad CO wings trace a giant molecular outflow of about 700 M_⊙/year, far larger than the ongoing star-formation rate (~200 M_⊙/year) observed in the host galaxy. This wind will totally expel the cold gas reservoir in Mrk 231 in about 107 yrs, therefore halting the star-formation activity on the same timescale. The inferred kinetic energy in the molecular outflow is ~1.2 × 1044 erg/s, corresponding to a few percent of the AGN bolometric luminosity, which is very close to the fraction expected by models ascribing quasar feedback to highly supersonic shocks generated by radiatively accelerated nuclear winds. Instead, the contribution by the SNe associated with the starburst fall short by several orders of magnitude to account for the kinetic energy observed in the outflow. The direct observational evidence for quasar feedback reported here provides solid support to the scenarios ascribing the observed properties of local massive

  18. Empirical densities, kinetic temperatures, and outflow velocities in the equatorial streamer belt at solar minimum

    NASA Astrophysics Data System (ADS)

    Strachan, L.; Suleiman, R.; Panasyuk, A. V.; Biesecker, D. A.; Kohl, J. L.

    2002-05-01

    We use combined Ultraviolet Coronagraph Spectrometer (UVCS) and Large Angle Spectroscopic Coronagraph (LASCO) data to determine the O(5+) outflow velocities as a function of height along the axis of an equatorial streamer at solar minimum and as a function of latitude (at 2.3 solar radii from sun center). The results show that outflow increases rather abruptly in the region between 3.6 and 4.1 solar radii near the streamer cusp, and gradually increases to 90 km/s at about 5 solar radii in the streamer stalk beyond the cusp. The latitudinal variation at 2.3 solar radii shows that there is no outflow (within the measurement uncertainties) in the center of the streamer called the core, and that a steep increase in outflow occurs just beyond the streamer legs, where the O VI 1032 intensity relative to H I 1216 (Ly alpha) is higer than in the core. Velocity variations in both height and latitude show that the transitions from no measurable outflow to positive outflow are relatively sharp and thus can be used to infer the location of the transition from closed to open field lines in streamer magnetic field topologies. Such information, including the densities and kinetic temperatures derived from the observations, provides hard constraints for realistic theoretical models of streamers and the source regions of the slow solar wind. This work is supported by NASA Grant NAG5-11420 to the Smithsonian Astrophysical Observatory, by the Italian Space Agency, and by the ESA PRODEX program (Swiss contribution). do not accept author defined LaTeX macros.

  19. A variable P v broad absorption line and quasar outflow energetics

    NASA Astrophysics Data System (ADS)

    Capellupo, D. M.; Hamann, F.; Barlow, T. A.

    2014-10-01

    Broad absorption lines (BALs) in quasar spectra identify high-velocity outflows that might exist in all quasars and could play a major role in feedback to galaxy evolution. The viability of BAL outflows as a feedback mechanism depends on their kinetic energies, as derived from the outflow velocities, column densities, and distances from the central quasar. We estimate these quantities for the quasar, Q1413+1143 (redshift ze = 2.56), aided by the first detection of P V λλ1118, 1128 BAL variability in a quasar. In particular, P V absorption at velocities where the C IV trough does not reach zero intensity implies that the C IV BAL is saturated and the absorber only partially covers the background continuum source (with characteristic size <0.01 pc). With the assumption of solar abundances, we estimate that the total column density in the BAL outflow is log NH ≳ 22.3 cm-2. Variability in the P V and saturated C IV BALs strongly disfavours changes in the ionization as the cause of the BAL variability, but supports models with high column density BAL clouds moving across our lines of sight. The observed variability time of 1.6 yr in the quasar rest frame indicates crossing speeds >750 km s-1 and a radial distance from the central black hole of ≲ 3.5 pc, if the crossing speeds are Keplerian. The total outflow mass is ˜4100 M⊙, the kinetic energy ˜4 × 1054 erg, and the ratio of the outflow kinetic energy luminosity to the quasar bolometric luminosity is ˜0.02 (at the minimum column density and maximum distance), which might be sufficient for important feedback to the quasar's host galaxy.

  20. Relativistic baryonic jets from an ultraluminous supersoft X-ray source.

    PubMed

    Liu, Ji-Feng; Bai, Yu; Wang, Song; Justham, Stephen; Lu, You-Jun; Gu, Wei-Min; Liu, Qing-Zhong; Di Stefano, Rosanne; Guo, Jin-Cheng; Cabrera-Lavers, Antonio; Álvarez, Pedro; Cao, Yi; Kulkarni, Shri

    2015-12-01

    The formation of relativistic jets by an accreting compact object is one of the fundamental mysteries of astrophysics. Although the theory is poorly understood, observations of relativistic jets from systems known as microquasars (compact binary stars) have led to a well established phenomenology. Relativistic jets are not expected to be produced by sources with soft or supersoft X-ray spectra, although two such systems are known to produce relatively low-velocity bipolar outflows. Here we report the optical spectra of an ultraluminous supersoft X-ray source (ULS) in the nearby galaxy M81 (M81 ULS-1; refs 9, 10). Unexpectedly, the spectra show blueshifted, broad Hα emission lines, characteristic of baryonic jets with relativistic speeds. These time-variable emission lines have projected velocities of about 17 per cent of the speed of light, and seem to be similar to those from the prototype microquasar SS 433 (refs 11, 12). Such relativistic jets are not expected to be launched from white dwarfs, and an origin from a black hole or a neutron star is hard to reconcile with the persistence of M81 ULS-1's soft X-rays. Thus the unexpected presence of relativistic jets in a ULS challenges canonical theories of jet formation, but might be explained by a long-speculated, supercritically accreting black hole with optically thick outflows. PMID:26605521

  1. A HOT MOLECULAR OUTFLOW DRIVEN BY THE IONIZED JET ASSOCIATED WITH IRAS 16562-3959

    SciTech Connect

    Guzman, Andres E.; Garay, Guido; Rathborne, Jill; Brooks, Kate J.; Guesten, Rolf

    2011-08-01

    We report molecular line observations in the CO J = 3 {yields} 2, 6 {yields} 5, and 7 {yields} 6 transitions, made using the Atacama Pathfinder Experiment Telescope, toward the massive and dense core IRAS 16562-3959. This core harbors a string of radio sources thought to be powered by a central collimated jet of ionized gas. The molecular observations show the presence of high-velocity gas exhibiting a quadrupolar morphology, most likely produced by the presence of two collimated outflows. The southeast-northwest (SE-NW) molecular outflow is aligned with the string of radio continuum sources, suggesting it is driven by the jet. We find that the excitation temperature of the gas in the SE-NW outflow is high, with values of 145 and 120 K for the blueshifted and redshifted lobes, respectively. This outflow has a total mass of 1.92 M{sub sun}, a total momentum of {approx}89 M{sub sun} km s{sup -1}, and an averaged momentum rate of {approx}3.0 x 10{sup -2} M{sub sun} km s{sup -1} yr{sup -1}, values characteristic of flows driven by young massive stellar objects with high luminosities (L{sub bol} {approx} 2 x 10{sup 4} L{sub sun}). Complementary data taken with the Atacama Submillimeter Telescope Experiment in high density and shock tracers support the picture that IRAS 16562-3959 is an accreting young massive star associated with an ionized jet, which is the energy source of a molecular outflow.

  2. Supernova blast wave within a stellar cluster outflow

    NASA Astrophysics Data System (ADS)

    Rodríguez-Ramírez, J. C.; Raga, A. C.; Velázquez, P. F.; Rodríguez-González, A.; Toledo-Roy, J. C.

    2014-11-01

    In this paper, we develop a semi-analytic model of a supernova which goes off in the centre of a stellar cluster. The supernova remnant interacts with a stratified, pre-existent outflow produced by the winds of the cluster stars. We compare our semi-analytic model with numerical simulations using the spherically symmetric Euler equations with appropriate mass and energy source terms. We find good agreement between these two approaches, and we find that for typical parameters the blast wave is likely to reach the Taylor-Sedov regime outside the cluster radius. We also calculate the predicted X-ray luminosity of the flow as a function of time, and we obtain its dependence on the outer radius and the number of stars of the cluster.

  3. The Prevalence of Gas Outflows in Type 2 AGNs. II. 3D Biconical Outflow Models

    NASA Astrophysics Data System (ADS)

    Bae, Hyun-Jin; Woo, Jong-Hak

    2016-09-01

    We present 3D models of biconical outflows combined with a thin dust plane for investigating the physical properties of the ionized gas outflows and their effect on the observed gas kinematics in type 2 active galactic nuclei (AGNs). Using a set of input parameters, we construct a number of models in 3D and calculate the spatially integrated velocity and velocity dispersion for each model. We find that three primary parameters, i.e., intrinsic velocity, bicone inclination, and the amount of dust extinction, mainly determine the simulated velocity and velocity dispersion. Velocity dispersion increases as the intrinsic velocity or the bicone inclination increases, while velocity (i.e., velocity shifts with respect to systemic velocity) increases as the amount of dust extinction increases. Simulated emission-line profiles well reproduce the observed [O iii] line profiles, e.g., narrow core and broad wing components. By comparing model grids and Monte Carlo simulations with the observed [O iii] velocity–velocity dispersion distribution of ∼39,000 type 2 AGNs, we constrain the intrinsic velocity of gas outflows ranging from ∼500 to ∼1000 km s‑1 for the majority of AGNs, and up to ∼1500–2000 km s‑1 for extreme cases. The Monte Carlo simulations show that the number ratio of AGNs with negative [O iii] velocity to AGNs with positive [O iii] velocity correlates with the outflow opening angle, suggesting that outflows with higher intrinsic velocity tend to have wider opening angles. These results demonstrate the potential of our 3D models for studying the physical properties of gas outflows, applicable to various observations, including spatially integrated and resolved gas kinematics.

  4. Analysing specificity of a bipolar EEG measurement.

    PubMed

    Vaisanen, Juho; Ryynanen, Outi; Hyttinen, Jari; Malmivuo, Jaakko

    2006-01-01

    The objective in bioelectric measurements such as ECG and EEG is to register the signal arising from sources in the region of interest. It is also desired that signal-to-noise ratio (SNR) of a measurement is high. The sensitivity of an ideal measurement should focus on and be greater on the target areas in comparison to other areas of the volume conductor. Previously the half-sensitivity volume (HSV) has been applied to describe how focused the measurement is. In this paper we introduce a concept of the half-sensitivity ratio (HSR) which describes how well the sensitivity is concentrated in HSV compared to other source regions i.e. how specific the measurement is to the sources in HSV. Further we may have different region of interests (ROI) to which the measurements are wanted to be specific. Then the concept is called region of interest sensitivity ratio (ROISR). We present here an application of the HSR in analysing sensitivity distributions of bioelectric measurements. We studied the effects of interelectrode distance and the scalp/skull/brain resistivity ratio on the HSR of a bipolar EEG measurement with a three-layer spherical head model. The results indicate that when the focus of interest is on cortical activity more specified and concentrated sensitivity distributions are achieved with smaller interelectrode distances. Further a preliminary measurement with visual evoked potentials provides evidence of the relationship between HSR and SNR of a measurement. PMID:17945619

  5. Cooling and Freshening of the Weddell Sea Outflow

    NASA Astrophysics Data System (ADS)

    Heywood, K. J.; Thompson, A. F.; Fahrbach, E.; Mackensen, A.; Aoki, S.

    2009-04-01

    The Weddell Sea is the primary source of the coldest, densest water invading most of the world ocean, known as Antarctic Bottom Water. The formation process involves brine rejection during sea ice formation, which salinifies the relatively fresh waters on the Antarctic continental shelf. Mixing with meltwater from the floating Antarctic ice shelves is believed to contribute also. When it becomes sufficiently dense, the shelf waters can spill down the continental slope as a deep outflow plume, mixing as it descends with the warmer and saltier Warm Deep Water above. By the time the plume reaches the western Weddell Sea, it is a narrow ribbon of cold, dense water hugging the continental slope. Here we will show that this outflow is now colder and fresher than in any of the observations since 1989. This freshening is comparable in magnitude to that seen in bottom water off Adelie Land which implies that the freshening is circumpolar, contrary to some recent analyses. This is likely associated with freshening of source waters on the continental shelf of Antarctica caused by an accelerated hydrological cycle and/or additional melting of the Antarctic ice sheet. Such melting may in turn be caused by a strengthening of the circumpolar winds associated with the Southern Annular Mode, leading to a southward ocean transport of heat towards the Antarctic. The Weddell Sea freshening may have been exacerbated by the break-up of the Larsen Ice Shelf on the eastern Antarctic Peninsula in the late 1990s, leaving a large expanse of continental shelf able to host the formation of sea ice and hence form dense bottom water.

  6. Ultrafast outflows in radio-loud active galactic nuclei

    NASA Astrophysics Data System (ADS)

    Tombesi, F.; Tazaki, F.; Mushotzky, R. F.; Ueda, Y.; Cappi, M.; Gofford, J.; Reeves, J. N.; Guainazzi, M.

    2014-09-01

    Recent X-ray observations show absorbing winds with velocities up to mildly relativistic values of the order of ˜0.1c in a limited sample of six broad-line radio galaxies. They are observed as blueshifted Fe XXV-XXVI K-shell absorption lines, similarly to the ultrafast outflows (UFOs) reported in Seyferts and quasars. In this work we extend the search for such Fe K absorption lines to a larger sample of 26 radio-loud active galactic nuclei (AGN) observed with XMM-Newton and Suzaku. The sample is drawn from the Swift Burst Alert Telescope 58-month catalogue and blazars are excluded. X-ray bright Fanaroff-Riley Class II radio galaxies constitute the majority of the sources. Combining the results of this analysis with those in the literature we find that UFOs are detected in >27 per cent of the sources. However, correcting for the number of spectra with insufficient signal-to-noise ratio, we can estimate that the incidence of UFOs is this sample of radio-loud AGN is likely in the range f ≃ (50 ± 20) per cent. A photoionization modelling of the absorption lines with XSTAR allows us to estimate the distribution of their main parameters. The observed outflow velocities are broadly distributed between vout ≲ 1000 km s-1 and vout ≃ 0.4c, with mean and median values of vout ≃ 0.133c and vout ≃ 0.117c, respectively. The material is highly ionized, with an average ionization parameter of logξ ≃ 4.5 erg s-1 cm, and the column densities are larger than NH > 1022 cm-2. Overall, these characteristics are consistent with the presence of complex accretion disc winds in a significant fraction of radio-loud AGN and demonstrate that the presence of relativistic jets does not preclude the existence of winds, in accordance with several theoretical models.

  7. X-RAY OUTFLOWS IN THE SWIFT BURST ALERT DETECTED SEYFERT 1s

    SciTech Connect

    Winter, Lisa M.

    2010-12-20

    Previous surveys of outflows in low-redshift active galactic nuclei (AGNs) have relied on the analysis of sources selected primarily for their optical/X-ray brightness and are therefore biased. Toward determining the outflow properties of local AGNs, we detect warm absorption signatures of O VII and O VIII absorption edges in the available Suzaku/XMM-Newton CCD spectra of an unbiased sample of 44 Seyfert 1-1.5 sources selected in the very hard X-rays (14-195 keV) with the Swift Burst Alert Telescope. From our analysis, we find that O VII and O VIII absorption edges are present in 41% of the sample. This fraction is dependent on luminosity, with outflow detections in 60% of low-luminosity and 30% of high-luminosity sources. However, grating spectroscopy of the highest luminosity sources reveals that {approx}80% of these sources have ionized absorbers, but that the ionization states are higher/lower than produces the O VII and O VIII edges. This suggests that ionized absorption may be present in all local Seyfert 1s.

  8. Ground-water outflow from Chino Basin, Upper Santa Ana Valley, southern California

    USGS Publications Warehouse

    French, James J.

    1972-01-01

    year. Two indirect methods of calculating ground-water outflow were studied as a part of this project: the chemical method and the water-budget method. The chemical method was found to be unsatisfactory. Although the ground-water discharge into the Santa Ana River from Chino basin is quite different in chemical composition from the discharge from Temescal basin, there is no known way to quantitatively separate the total discharge with respect to source. In the water-budget method direct runoff and evapotranspiration were reevaluated, and the ground-water outflow from Temescal basin was calculated by the same direct method employed for Chino basin. Annual ground-water outflow from Temescal basin calculated by the direct method for the period 1930-66 ranged from 11,000 acre-feet in the 1940 and 1945 water years to 3,000 acre-feet in the 1965 water year. Annual ground-water outflow from Chino basin computed by the water-budget method for the period 1933-63 ranged from 45,000 acre-feet in the 1941 water year to 10,000 acre-feet in the 1963 water year.

  9. Improved quantification of Chinese carbon fluxes using CO2/CO correlations in Asian outflow

    NASA Astrophysics Data System (ADS)

    Suntharalingam, Parvadha; Jacob, Daniel J.; Palmer, Paul I.; Logan, Jennifer A.; Yantosca, Robert M.; Xiao, Yaping; Evans, Mathew J.; Streets, David G.; Vay, Stephanie L.; Sachse, Glen W.

    2004-09-01

    We use observed CO2:CO correlations in Asian outflow from the TRACE-P aircraft campaign (February-April 2001), together with a three-dimensional global chemical transport model (GEOS-CHEM), to constrain specific components of the east Asian CO2 budget including, in particular, Chinese emissions. The CO2/CO emission ratio varies with the source of CO2 (different combustion types versus the terrestrial biosphere) and provides a characteristic signature of source regions and source type. Observed CO2/CO correlation slopes in east Asian boundary layer outflow display distinct regional signatures ranging from 10-20 mol/mol (outflow from northeast China) to 80 mol/mol (over Japan). Model simulations using best a priori estimates of regional CO2 and CO sources from [2003] (anthropogenic), the CASA model (biospheric), and [2003] (biomass burning) overestimate CO2 concentrations and CO2/CO slopes in the boundary layer outflow. Constraints from the CO2/CO slopes indicate that this must arise from an overestimate of the modeled regional net biospheric CO2 flux. Our corrected best estimate of the net biospheric source of CO2 from China for March-April 2001 is 3200 Gg C/d, which represents a 45% reduction of the net flux from the CASA model. Previous analyses of the TRACE-P data had found that anthropogenic Chinese CO emissions must be ˜50% higher than in 's [2003] inventory. We find that such an adjustment improves the simulation of the CO2/CO slopes and that it likely represents both an underreporting of sector activity (domestic and industrial combustion) and an underestimate of CO emission factors. Increases in sector activity would imply increases in Chinese anthropogenic CO2 emissions and would also imply a further reduction of the Chinese biospheric CO2 source to reconcile simulated and observed CO2 concentrations.

  10. Evaluating the Importance of Outflow Velocity at the MHD Inner Boundary

    NASA Astrophysics Data System (ADS)

    Welling, D. T.; Liemohn, M. W.; Toth, G.; Glocer, A.

    2013-12-01

    Including an ionospheric source of magnetospheric plasma in global magnetohydrodynamic models (MHD) is an exercise in setting inner boundary mass density and radial velocity. Recently, in order to account for the complex processes that accelerate plasmas up from ionospheric altitudes to MHD inner boundary altitudes (typically 2.5 to 3 Earth Radii), empirical and first-principles-based models have been developed to set inner boundary conditions in a dynamic and activity-dependent manner. However, such measures are not necessary to achieve outflowing fluences of the order observed by various spacecraft. Spatially and temporally constant boundary conditions, even with zero radial velocity, have been shown to produce dynamic outflow patterns and supply the bulk of magnetospheric plasma. Noteworthy of this approach is the inherent assumption that no acceleration has occurred between the ionosphere and the inner boundary, that is, the ionosphere is simply a mass reservoir. This assumption is contrary to our understanding of the magnetosphere-ionosphere system, yet the net result - outflowing heavy and light ions that populate the rest of geospace - is similar to that when a more realistic outflow specification is applied. The implication is that radial velocity matters little when supplying outflow to global MHD models. This paper investigates the importance of radial velocity at the inner boundary of MHD codes in driving ionospheric outflows into the greater domain. Multi-fluid BATS-R-US is used to simulate an idealized storm, first using zero radial velocity at the inner boundary, then non-zero constant values, and finally with spatially and temporally dynamic values driven by the Polar Wind Outflow Model (PWOM), which sets radial velocity and number density based on physics-based modeling of gap region populations. The results, in terms of total fluence, spatial outflowing flux patterns, and overall magnetospheric response, are compared to investigate how the

  11. Swimming in Deep Water: Childhood Bipolar Disorder

    ERIC Educational Resources Information Center

    Senokossoff, Gwyn W.; Stoddard, Kim

    2009-01-01

    The authors focused on one parent's struggles in finding a diagnosis and intervention for a child who had bipolar disorder. The authors explain the process of identification, diagnosis, and intervention of a child who had bipolar disorder. In addition to the personal story, the authors provide information on the disorder and outline strategies…

  12. Bipolar Disorder in School-Age Children

    ERIC Educational Resources Information Center

    Olson, Patricia M.; Pacheco, Mary Rae

    2005-01-01

    This article examines the individual components of bipolar disorder in children and the behaviors that can escalate as a result of misdiagnosis and treatment. The brain/behavior relationship in bipolar disorders can be affected by genetics, developmental failure, or environmental influences, which can cause an onset of dramatic mood swings and…

  13. Bipolar Disorder and Cognitive Therapy: A Commentary

    ERIC Educational Resources Information Center

    Riskind, John H.

    2005-01-01

    This article comments on the three articles (Leahy, 2005; Newman, 2005; and Reilly-Harrington & Knauz, 2005) that deal with the applications of cognitive therapy to treatment of bipolar disorder. They focus on the uses of cognitive therapy in treating three important facets of the special problems of bipolar patients: rapid cycling, severe…

  14. Bipolar disorder diagnosis: challenges and future directions.

    PubMed

    Phillips, Mary L; Kupfer, David J

    2013-05-11

    Bipolar disorder refers to a group of affective disorders, which together are characterised by depressive and manic or hypomanic episodes. These disorders include: bipolar disorder type I (depressive and manic episodes: this disorder can be diagnosed on the basis of one manic episode); bipolar disorder type II (depressive and hypomanic episodes); cyclothymic disorder (hypomanic and depressive symptoms that do not meet criteria for depressive episodes); and bipolar disorder not otherwise specified (depressive and hypomanic-like symptoms that do not meet the diagnostic criteria for any of the aforementioned disorders). Bipolar disorder type II is especially difficult to diagnose accurately because of the difficulty in differentiation of this disorder from recurrent unipolar depression (recurrent depressive episodes) in depressed patients. The identification of objective biomarkers that represent pathophysiologic processes that differ between bipolar disorder and unipolar depression can both inform bipolar disorder diagnosis and provide biological targets for the development of new and personalised treatments. Neuroimaging studies could help the identification of biomarkers that differentiate bipolar disorder from unipolar depression, but the problem in detection of a clear boundary between these disorders suggests that they might be better represented as a continuum of affective disorders. Innovative combinations of neuroimaging and pattern recognition approaches can identify individual patterns of neural structure and function that accurately ascertain where a patient might lie on a behavioural scale. Ultimately, an integrative approach, with several biological measurements using different scales, could yield patterns of biomarkers (biosignatures) to help identify biological targets for personalised and new treatments for all affective disorders. PMID:23663952

  15. Thomson semiconductors bipolar IC strategy to 1986

    NASA Astrophysics Data System (ADS)

    Dellamussia, J. P.

    1984-04-01

    The strategy to develop and market bipolar integrated circuits through 1986 by thomson semiconductors is discussed. Current technology and future research on prototype microprocessors using bipolar integrated circuits is evaluated. The physical properties of the circuits such as heat dissipation, energy consumption rates and response times are studied.

  16. Modeling "Soft" Errors in Bipolar Integrated Circuits

    NASA Technical Reports Server (NTRS)

    Zoutendyk, J.; Benumof, R.; Vonroos, O.

    1985-01-01

    Mathematical models represent single-event upset in bipolar memory chips. Physics of single-event upset in integrated circuits discussed in theoretical paper. Pair of companion reports present mathematical models to predict critical charges for producing single-event upset in bipolar randomaccess memory (RAM) chips.

  17. Adjunctive Psychotherapy for Bipolar Disorder

    PubMed Central

    Miklowitz, David J.

    2008-01-01

    Objective Psychotherapy has long been recommended as adjunctive to pharmacotherapy for bipolar disorder, but it is unclear which interventions are effective for which patients, over what intervals, and for what domains of outcome. This article reviews randomized trials of adjunctive psychotherapy for bipolar disorder. Method Eighteen trials of individual and group psychoeducation, systematic care, family therapy, interpersonal therapy, and cognitive-behavioral therapy are described. Relevant outcome variables include time to recovery, recurrence, duration of episodes, symptom severity, and psychosocial functioning. Results The effects of the treatment modalities varied according to the clinical condition of patients at the time of random assignment and the polarity of symptoms at follow-up. Family therapy, interpersonal therapy, and systematic care appeared to be most effective in preventing recurrences when initiated after an acute episode, whereas cognitive-behavioral therapy and group psychoeducation appeared to be most effective when initiated during a period of recovery. Individual psychoeducational and systematic care programs were more effective for manic than depressive symptoms, whereas family therapy and cognitive-behavioral therapy were more effective for depressive than manic symptoms. Conclusions Adjunctive psychotherapy enhances the symptomatic and functional outcomes of bipolar disorder over 2-year periods. The various modalities differ in content, structure, and associated mediating mechanisms. Treatments that emphasize medication adherence and early recognition of mood symptoms have stronger effects on mania, whereas treatments that emphasize cognitive and interpersonal coping strategies have stronger effects on depression. The placement of psychotherapy within chronic care algorithms and its role as a preventative agent in the early stages of the disorder deserve investigation. PMID:18794208

  18. DIRECT IMAGING OF A COMPACT MOLECULAR OUTFLOW FROM A VERY LOW LUMINOSITY OBJECT: L1521F-IRS

    SciTech Connect

    Takahashi, Satoko; Ohashi, Nagayoshi; Bourke, Tyler L.

    2013-09-01

    Studying the physical conditions of very low luminosity objects (VeLLOs; L{sub bol} < 0.1 L{sub Sun }) is important for understanding the earliest evolutionary stage of protostars and brown dwarfs. We report interferometric observations of the VeLLO L1521F-IRS, in {sup 12}CO (2-1) line emission and the 1.3 mm continuum emission, using the Submillimeter Array. With the {sup 12}CO (2-1) high-resolution observations, we have spatially resolved a compact but poorly collimated molecular outflow associated with L1521F-IRS for the first time. The blueshifted and redshifted lobes are aligned along the east and west side of L1521F-IRS with a lobe size of Almost-Equal-To 1000 AU. The estimated outflow mass, maximum outflow velocity, and outflow force are (9.0-80) Multiplication-Sign 10{sup -4} M{sub Sun }, 7.2 km s{sup -1}, and (7.4-66) Multiplication-Sign 10{sup -7} M{sub Sun} km s{sup -1} yr{sup -1}, respectively. The estimated outflow parameters such as size, mass, and momentum rate are similar to values derived for other VeLLOs, and are located at the lower end of values compared to previously studied outflows associated with low- to high-mass star-forming regions. Low-velocity less collimated (1.5 km s{sup -1}/1200 AU) and higher-velocity compact (4.0 km s{sup -1}/920 AU) outflow components are suggested by the data. These velocity structures are not consistent with those expected in the jet-driven or wind-driven outflow models, perhaps suggesting a remnant outflow from the first hydrostatic core as well as an undeveloped outflow from the protostar. Detection of an infrared source and compact millimeter continuum emission suggests the presence of the protostar, while its low bolometric luminosity (0.034-0.07 L{sub Sun }) and small outflow suggests that L1521F is in the earliest protostellar stage (<10{sup 4} yr) and contains a substellar mass object. The bolometric (or internal) luminosity of L1521F-IRS suggests that the current mass accretion rate is an order of

  19. Requirements for theoretical models of outflows

    NASA Technical Reports Server (NTRS)

    Linsky, Jeffrey L.

    1988-01-01

    Recent observational and theoretical investigations of astrophysical mass outflows are reviewed, with a focus on the basic physical principles. Specific limitations on the observational data and their interpretation are listed and discussed. Modeling problems considered include the role of the critical point in determining the mass-loss rate and terminal velocity, the physical processes controlling density at the critical point, the possible coexistence of multiple mass-loss mechanisms, time scales, instabilities and phase changes, multiphase atmospheres and winds, the definition of geometries, the role of the environment, explosive transient events, stochastic phenomena, mode-mode coupling and damping processes, departures from ionization equilibrium, and nonthermal phenomena.

  20. Shock Waves in Outflows from Young Stars

    NASA Astrophysics Data System (ADS)

    Hartigan, Patrick

    This review focuses on physics of the cooling zones behind radiative shocks and the emission line diagnostics that can be used to infer physical conditions and mass loss rates in jets from young stars. Spatial separations of the cooling zones from the shock fronts, now resolvable with HST, and recent evidence for C-shocks have greatly increased our understanding of how shocks in outflows interact with the surrounding medium and with other material within the flow. By combining multiple epoch HST images, one can create `movies' of flows like those produced from numerical codes, and learn what kinds of instabilities develop within these systems.

  1. Valles Marineris and Chryse Outflow Channels

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A color image of Valles Marineris, the great canyon and the south Chryse basin-Valles Marineris outflow channels of Mars; north toward top. The scene shows the entire Valles Marineris canyon system, over 3,000 km long and averaging 8 km deep, extending from Noctis Labyrinthus, the arcuate system of graben to the west, to the chaotic terrain to the east and related outflow canyons that drain toward the Chryse basin. Eos and Capri Chasmata (south to north) are two canyons connected to Valles Marineris. Ganges Chasma lies directly north. The chaos in the southeast part of the image gives rise to several outflow channels, Shalbatana, Simud, Tiu, and Ares Valles (left to right), that drained north into the Chryse basin. The mouth of Ares Valles is the site of the Mars Pathfinder lander.

    This image is a composite of Viking medium-resolution images in black and white and low-resolution images in color; Mercator projection. The image roughly extends from latitude 20 degrees S. to 20 degrees N. and from longitude 15 degrees to 102.5 degrees.

    The connected chasma or valleys of Valles Marineris may have formed from a combination of erosional collapse and structural activity. Layers of material in the eastern canyons might consist of carbonates deposited in ancient lakes, eolian deposits, or volcanic materials. Huge ancient river channels began from Valles Marineris and from adjacent canyons and ran north. Many of the channels flowed north into Chryse Basin.

    The south Chryse outflow channels are cut an average of 1 km into the cratered highland terrain. This terrain is about 9 km above datum near Valles Marineris and steadily decreases in elevation to 1 km below datum in the Chryse basin. Shalbatana is relatively narrow (10 km wide) but can reach 3 km in depth. The channel begins at a 2- to 3-km-deep circular depression within a large impact crater, whose floor is partly covered by chaotic material, and ends in Simud Valles. Tiu and Simud Valles consist of a

  2. ATOMIC HYDROGEN IN A GALACTIC CENTER OUTFLOW

    SciTech Connect

    McClure-Griffiths, N. M.; Green, J. A.; Hill, A. S.; Lockman, F. J.; Dickey, J. M.; Gaensler, B. M.; Green, A. J.

    2013-06-10

    We describe a population of small, high-velocity, atomic hydrogen clouds, loops, and filaments found above and below the disk near the Galactic center. The objects have a mean radius of 15 pc, velocity widths of {approx}14 km s{sup -1}, and are observed at |z| heights up to 700 pc. The velocity distribution of the clouds shows no signature of Galactic rotation. We propose a scenario where the clouds are associated with an outflow from a central star-forming region at the Galactic center. We discuss the clouds as entrained material traveling at {approx}200 km s{sup -1} in a Galactic wind.

  3. GGD 37: AN EXTREME PROTOSTELLAR OUTFLOW

    SciTech Connect

    Green, J. D.; Watson, D. M.; Forrest, W. J.; Kim, K. H.; Bergin, E.; Maret, S.; Melnick, G.; Tolls, V.; Sonnentrucker, P.; Sargent, B. A.; Raines, S. N.

    2011-01-01

    We present the first Spitzer-IRS spectral maps of the Herbig-Haro flow GGD 37 detected in lines of [Ne III], [O IV], [Ar III], and [Ne V]. The detection of extended [O IV] (55 eV) and some extended emission in [Ne V] (97 eV) indicates a shock temperature in excess of 100,000 K, in agreement with X-ray observations, and a shock speed in excess of 200 km s{sup -1}. The presence of an extended photoionization or collisional ionization region indicates that GGD 37 is a highly unusual protostellar outflow.

  4. Bipolar Ag-Zn battery

    NASA Astrophysics Data System (ADS)

    Giltner, L. John

    1994-02-01

    The silver-zinc (AgZn) battery system has been unique in its ability to safely satisfy high power demand applications with low mass and volume. However, a new generation of defense, aerospace, and commercial applications will impose even higher power demands. These new power demands can be satisfied by the development of a bipolar battery design. In this configuration the power consuming, interelectrode current conductors are eliminated while the current is then conducted via the large cross-section electrode substrate. Negative and positive active materials are applied to opposite sides of a solid silver foil substrate. In addition to reducing the weight and volume required for a specified power level, the output voltage performance is also improved as follows. Reduced weight through: elimination of the plastic cell container; elimination of plate leads and intercell connector; and elimination of internal plate current collector. Increased voltage through: elimination of resistance of current collector; elimination of resistance of plate lead; and elimination of resistance of intercell connector. EPI worked previously on development of a secondary bipolar silver zinc battery. This development demonstrated the electrical capability of the system and manufacturing techniques. One difficulty with this development was mechanical problems with the seals. However, recent improvements in plastics and adhesives should eliminate the major problem of maintaining a seal around the periphery of the bipolar module. The seal problem is not as significant for a primary battery application or for a requirement for only a few discharge cycles. A second difficulty encountered was with activation (introducing electrolyte into the cell) and with venting gas from the cell without loss of electrolyte. During previous work, the following projections for energy density were made from test data for a high power system which demonstrated in excess of 50 discharge/charge cycles. Projected

  5. [Child and adolescent bipolar disorder].

    PubMed

    Aichhorn, Wolfgang; Stuppäck, Christoph; Kralovec, Karl; Yazdi, Kurosch; Aichhorn, Monika; Hausmann, Armand

    2007-01-01

    The onset of bipolar disorders before the age of 10 is rare. First manifestation occurs most frequently between the age of 15 to 30. Children of a parent with bipolar disorder are at a fivefold risk for developing a bipolar disorder. Therefore, an elaborate family-history is essential for the assessment of potentially manic or depressive symptoms in children and adolescents. Basically, for all age groups the same diagnostic criteria according to ICD 10 are applied. Due to the differing symptoms for children and adolescents the finding of a diagnosis is considerably harder than for adults. Manic episodes before the age of 10 are characterized by increased activity, more risk taking behaviour and elevated emotional instability. In adolescents, however, behavioural disturbance with antisocial behaviour and drug-abuse are more common. Thus, typical misdiagnosis as ADHD or conduct disorders for children and adolescents are frequent. Aggravating the complexity, in up to 90 % both differential-diagnosis may occur as comorbid disorders. Furthermore, psychotic symptoms are more common than in adults and dysphoria is more likely than euphoric or depressive mood. Asymptomatic intervals rarely exist, whereas "ups" and "downs" in rapid succession are prevailing (rapid cycling). An early diagnosis, leading specific treatment, is essential for the prognosis of bipolar disorders. Additionally, structural (CCT or MRI) and laboratory examination are essential to expel endocrine or brain-organic diseases. Besides psychotherapeutic and psychoeducative methods, always including parents and attached persons, the psychopharmacological treatment is a major part of a multimodal treatment. The available substances partly have been in use for years and are appropriate for youngsters. These include mood stabilizers like lithium, divalproex and carbamazepine, which provide besides their acute antimanic effects also relapse-prophylactic properties. In addition atypical antipsychotics like

  6. Bipolar Ag-Zn battery

    NASA Technical Reports Server (NTRS)

    Giltner, L. John

    1994-01-01

    The silver-zinc (AgZn) battery system has been unique in its ability to safely satisfy high power demand applications with low mass and volume. However, a new generation of defense, aerospace, and commercial applications will impose even higher power demands. These new power demands can be satisfied by the development of a bipolar battery design. In this configuration the power consuming, interelectrode current conductors are eliminated while the current is then conducted via the large cross-section electrode substrate. Negative and positive active materials are applied to opposite sides of a solid silver foil substrate. In addition to reducing the weight and volume required for a specified power level, the output voltage performance is also improved as follows. Reduced weight through: elimination of the plastic cell container; elimination of plate leads and intercell connector; and elimination of internal plate current collector. Increased voltage through: elimination of resistance of current collector; elimination of resistance of plate lead; and elimination of resistance of intercell connector. EPI worked previously on development of a secondary bipolar silver zinc battery. This development demonstrated the electrical capability of the system and manufacturing techniques. One difficulty with this development was mechanical problems with the seals. However, recent improvements in plastics and adhesives should eliminate the major problem of maintaining a seal around the periphery of the bipolar module. The seal problem is not as significant for a primary battery application or for a requirement for only a few discharge cycles. A second difficulty encountered was with activation (introducing electrolyte into the cell) and with venting gas from the cell without loss of electrolyte. During previous work, the following projections for energy density were made from test data for a high power system which demonstrated in excess of 50 discharge/charge cycles. Projected

  7. A Morpho-kinematic and Spectroscopic study of Bipolar Planetary Nebulae

    NASA Astrophysics Data System (ADS)

    Clyne, Niall

    2015-09-01

    hypersonic knotty outflow. As for M 2-9, Mz 3, and Hen 2-104, the expansion rates of their individual components are better constrained and fitted with a vector field to reveal their direction of motion. Both diagnostic diagrams show M 2-9 and Hen 2-104 to fall well within the category of having a symbiotic source, whereas Mz 3 borders the region of symbiotic and young planetary nebulae in the optical diagram but is located firmly in the symbiotic region of the NIR colour-colour diagram. With regards to Abell 14, it has been shown to be a highly-evolved bipolar nebula with a kinematical age of 19,400 ± 3480 yr for a distance of 4 kpc, and is a nebula with a very-low density, which further implies its evolved state.

  8. Outflowing X-ray corona in Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Wang, Junxian; Liu, Teng; Yang, Huan; Zhu, Feifan; Zhou, Youyuan

    2015-08-01

    Hard X-ray emission in radio-quiet AGNs is believed to be produced via inverse Compton scattering by hot and compact corona near the super massive black hole. However the origin and physical properties of the coronae, including geometry, kinematics and dynamics, yet remain poorly known. Taking [OIV] 25.89um emission line as an isotropic indicator of AGN's intrinsic luminosity, we compare the intrinsic corona X-ray emission between Seyfert 1 and Compton-thin Seyfert 2 galaxies, which are viewed at different inclinations according to the unification scheme. We find that Seyfert 1 galaxies are brighter in "absorption-corrected" 2-10 keV emission by a factor of ~2.8, comparing with Compton-thin Seyfert 2 galaxies. The Seyfert 1 and Compton-thin Seyfert 2 galaxies follow a statistically identical correlation between the absorption-corrected 2-10 keV luminosity and the SWIFT BAT 14-195 keV luminosity, indicating that our absorption correction to the 2-10 keV flux is sufficient. The difference between the two populations thus can not be attributed to X-ray absorption, and instead implies an intrinsic anisotropy in the corona X-ray emission. This striking anisotropy of X-ray emission can be explained by a bipolar outflowing corona with a bulk velocity of ~0.3-0.5c. This would provide a natural link between the so-called coronae and weak jets in these systems. We also show that how this study would affect our understanding to the nature of mid-infrared emission in AGNs and the properties of dusty torus. Furthermore, such anisotropy implies that, contrary to previous understanding based on the assumption of isotropic corona emission, hard X-ray AGN surveys are biased against type 2 AGNs even after absorption-correction, and careful correction for this effect is required to measure the obscured fraction from X-ray surveys. Other interesting consequences of this discovery will also be discussed.

  9. Studying the outflow-core interaction with ALMA Cycle 1 observations of the HH 46/47 molecular outflow

    NASA Astrophysics Data System (ADS)

    Zhang, Yichen; Arce, Hector G.; Mardones, Diego; Dunham, Michael; Garay, Guido; Noriega-Crespo, Alberto; Corder, Stuartt; Offner, Stella; Cabrit, Sylvie

    2016-01-01

    We present ALMA Cycle 1 observations of the HH 46/47 molecular outflow which is driven by a low-mass Class 0/I protostar. Previous ALMA Cycle 0 12CO observation showed outflow cavities produced by the entrainment of ambient gas by the protostellar jet and wide-angle wind. Here we present analysis of observation of 12CO, 13CO, C18O and other species using combined 12m array and ACA observations. The improved angular resolution and sensitivity allow us to detect details of the outflow structure. Specially, we see that the outflow cavity wall is composed of two or more layers of outflowing gas, which separately connect to different shocked regions along the outflow axis inside the cavity, suggesting the outflow cavity wall is composed of multiple shells entrained by a series of jet bow-shock events. The new 13CO and C18O data also allow us to trace relatively denser and slower outflow material than that traced by the 12CO. These species are only detected within about 1 to 2 km/s from the cloud velocity, tracing the outflow to lower velocities than what is possible using only the 12CO emission. Interestingly, the cavity wall of the red lobe appears at very low outflow velocities (as low as ~0.2 km/s). In addition, 13CO and C18O allow us to correct for the CO optical depth, allowing us to obtain more accurate estimates of the outflow mass, momentum and kinetic energy. Applying the optical depth correction significantly increases the previous mass estimate by a factor of 14. The outflow kinetic energy distribution shows that even though the red lobe is mainly entrained by jet bow-shocks, most of the outflow energy is being deposited into the cloud at the base of the outflow cavity rather than around the heads of the bow shocks. The estimated total mass, momentum, and energy of the outflow indicate that the outflow has the ability to disperse the parent core. We found possible evidence for a slowly moving rotating outflow in CS. Our 13CO and C18O observations also trace a

  10. The prestige model of spectrum bipolarity.

    PubMed

    Le Bas, James; Newton, Richard; Sore, Rachel; Castle, David

    2015-02-01

    Because affective pathogenesis is a hard problem for psychiatry, it behoves researchers to develop and test novel models of causality. We examine the notion that the adaptive drive to social investment - prestige - provides clues to the bipolar spectrum. A seven node bipolar spectrum is proposed, based on a putative gradient of "bipolarity". It is conceived that this gradient may correlate with the drive to social investment (prestige). In order to test this hypothesis with proof of concept data, a case control study categorised 228 subjects into a seven node bipolar spectrum. Whilst controlling for mood elevation and depression, differences in strategic prestige (leadership) motivation (MSPM) between spectrum groups were examined. The bipolar I (S1) node had a greater strategic prestige (leadership) motivation score than the controls (S7) by 21.17 points, 95% CI [8.16, 34.18], p<.001, d=1.05, while the bipolar II (S2) node was higher than the control group by 16.73 points, 95% CI [0.92, 32.54], p=.030, d=0.84. Whilst the pseudounipolar (S3) node (those with depression and bipolar family histories; n=17) had only a marginally statistical difference in MSPM compared to controls (p=.051), the mean difference (16.98) and d value (0.86) indicated an elevated MSPM level. Prestige (leadership) motivation score positively correlated with dimensional lifetime bipolarity (Mood Disorder Questionnaire) score (rp=0.47), supporting the spectrum prestige motivation gradient notion. Evidence is presented for a genetic disposition to elevated strategic prestige (leadership) motivation. Sensitivity to Social Inclusion (MSIS), Contingency of Self-Worth (CSW.av) and tension significantly predicted strategic prestige (leadership) motivation (MSPM) score in a multiple regression. - suggesting that a vulnerability of the social self may be a feature of bipolar disorders. The prestige model of spectrum bipolarity offers a new conceptualisation of affective disorders and has received

  11. The baryonic Tully-Fisher relation and galactic outflows

    NASA Astrophysics Data System (ADS)

    Dutton, Aaron A.

    2012-08-01

    Most of the baryons in the Universe are not in the form of stars and cold gas in galaxies. Galactic outflows driven by supernovae/stellar winds are the leading mechanisms for explaining this fact. The scaling relation between galaxy mass and outer rotation velocity (also known as the baryonic Tully-Fisher relation, BTF) has recently been used as evidence against this viewpoint. We use a Λ cold dark matter (ΛCDM)-based semi-analytic disc galaxy formation model to investigate these claims. In our model, galaxies with less efficient star formation and higher gas fractions are more efficient at ejecting gas from galaxies. This somewhat counter intuitive result is due to the (observational) fact that galaxies with less efficient star formation and higher gas fractions tend to live in dark matter haloes with lower circular velocities, from which less energy is required to escape the potential well. In our model the intrinsic scatter in the BTF is ≃0.15 dex, and mostly reflects scatter in dark halo concentration. The scatter is largely independent of galaxy structure because of the large radius within which galaxy rotation velocities are measured. The observed scatter, equal to ≃0.24 dex, is dominated by measurement errors. The best estimate for the intrinsic scatter is that it is less than 0.15 dex, and thus our ΛCDM-based model (which does not include all possible sources of scatter) is only just consistent with this. Future observations of the BTF scatter could be made with a more stringent measurement of the intrinsic scatter, and thus provide a strong constraint to galaxy formation models. In our model, gas-rich galaxies, at fixed virial velocity (Vvir), with lower stellar masses have lower baryonic masses. This is consistent with the expectation that galaxies with lower stellar masses have had less energy available to drive an outflow. However, when the outer rotation velocity (Vflat) is used the correlation has the opposite sign, with a slope in agreement

  12. Endogenous Bioactive Lipids and the Regulation of Conventional Outflow Facility

    PubMed Central

    Wan, Zhou; Woodward, David F.; Stamer, W. Daniel

    2009-01-01

    Summary Perturbation of paracrine signaling within the human conventional outflow pathway influences tissue homeostasis and outflow function. For example, exogenous introduction of the bioactive lipids, sphingosine-1-phosphate, anandamide or prostaglandin F2α, to conventional outflow tissues alters the rate of drainage of aqueous humor through the trabecular meshwork, and into Schlemm’s canal. This review summarizes recent data that characterizes endogenous bioactive lipids, their receptors and associated signaling partners in the conventional outflow tract. We also discuss the potential of targeting such signaling pathways as a strategy for the development of therapeutics to treat ocular hypertension and glaucoma. PMID:19381354

  13. HiRes deconvolved Spitzer images of 89 protostellar jets and outflows: New data on the evolution of the outflow morphology

    SciTech Connect

    Velusamy, T.; Langer, W. D.; Thompson, T. E-mail: William.D.Langer@jpl.nasa.gov

    2014-03-01

    To study the role of protosellar jets and outflows in the time evolution of the parent cores and the protostars, the astronomical community needs a large enough database of infrared images of protostars at the highest spatial resolution possible to reveal the details of their morphology. Spitzer provides unprecedented sensitivity in the infrared to study both the jet and outflow features, however, its spatial resolution is limited by its 0.85 m mirror. Here, we use a high-resolution deconvolution algorithm, 'HiRes,' to improve the visualization of spatial morphology by enhancing resolution (to subarcsecond levels in the IRAC bands) and removing the contaminating side lobes from bright sources in a sample of 89 protostellar objects. These reprocessed images are useful for detecting (1) wide-angle outflows seen in scattered light, (2) morphological details of H{sub 2} emission in jets and bow shocks, and (3) compact features in MIPS 24 μm images as protostar/disk and atomic/ionic line emission associated with the jets. The HiRes FITS image data of such a large homogeneous sample presented here will be useful to the community in studying these protostellar objects. To illustrate the utility of this HiRes sample, we show how the opening angle of the wide-angle outflows in 31 sources, all observed in the HiRes-processed Spitzer images, correlates with age. Our data suggest a power-law fit to opening angle versus age with an exponent of ∼0.32 and 0.02, respectively, for ages ≤8000 yr and ≥8000 yr.

  14. Images of shock-excited molecular hydrogen in young stellar outflows

    NASA Technical Reports Server (NTRS)

    Garden, Rognvald P.; Russell, Adrian P. G.; Burton, Michael G.

    1990-01-01

    High-angular resolution molecular hydrogen (H2) v = 1-0 S(1) line images of several well-known molecular outflow sources (DR 21, NGC 2071, HH 7-11, and HH 12) are presented. It is found that all of the outflow sources possess highly collimated jets of shock-excited gas that are extremely clumpy and often consist of bright knots that are placed periodically along the jet axis. The H2 emission-line jets are significantly more collimated than their corresponding CO outflows and remain collimated to large distances from their driving source. In DR 21 and NGC 2071, the H2 jets appear to become more collimated with increasing distance from the central source, suggesting that they are pressure-confined by the ambient cloud medium. In HH 7-11 and HH 12 the shock-excited ionized and molecular components are spatially coincident and appear to be of comparable shape and size; this suggests that the shocked gas is highly mixed on scales significantly smaller than the current spatial resolution.

  15. Relativistic hadrons and the origin of relativistic outflows in active galactic nuclei

    NASA Technical Reports Server (NTRS)

    Contopoulos, John; Kazanas, D.

    1995-01-01

    We examine the hydrodynamic origin of relativistic outflows in active galactic nuclei (AGN). Specifically, we propose that the presence of a population of relativistic hadrons in the AGN 'central engine' and the associated neutron production suffices to produce outflows which under rather general conditions could be relativistic. The main such condition is that the size of the neutron production region be larger than the neutron flight path tau(sub n) approximately 3 x 10(exp 13) cm. This condition guarantees that the mean energy per particle in the proton fluid, resulting from the decay of the neutrons outside their production region, be greater than the proton rest mass. The expansion of this fluid can then lead naturally to a relativistic outflow by conversion of its internal energy to directed motion. We follow the development of such flows by solving the mass, energy as well as the kinetic equation for the proton gas in steady state, taking into account the source terms due to compute accurately the adiabatic index of the expanding gas, and in conjunction with Bernoulli's equation the detailed evolution of the bulk Lorentz factor. We further examine the role of large-scale magnetic fields in confining these outflows to produce the jets observed at larger scales.

  16. THE QUASAR OUTFLOW CONTRIBUTION TO AGN FEEDBACK: VLT MEASUREMENTS OF SDSS J0318-0600

    SciTech Connect

    Dunn, Jay P.; Bautista, Manuel; Arav, Nahum; Edmonds, Doug; Moe, Max; Korista, Kirk; Costantini, Elisa; Benn, Chris; Ellison, Sara E-mail: arav@vt.ed E-mail: kirk.korista@wmich.ed E-mail: mmoe@cfa.harvard.ed

    2010-02-01

    We present high spectral resolution Very Large Telescope observations of the broad absorption line quasar SDSS J0318 - 0600. This high-quality data set allows us to extract accurate ionic column densities and determine an electron number density of n{sub e} = 10{sup 3.3+}-{sup 0.2} cm{sup -3} for the main outflow absorption component. The heavily reddened spectrum of SDSS J0318-0600 requires purely silicate dust with a reddening curve characteristic of predominately large grains, from which we estimate the bolometric luminosity. We carry out photoionization modeling to determine the total column density, ionization parameter, and distance of the gas and find that the photoionization models suggest abundances greater than solar. Due to the uncertainty in the location of the dust extinction, we arrive at two viable distances for the main ouflow component from the central source, 6 and 17 kpc, where we consider the 6 kpc location as somewhat more physically plausible. Assuming the canonical global covering of 20% for the outflow and a distance of 6 kpc, our analysis yields a mass flux of 120 M{sub sun} yr{sup -1} and a kinetic luminosity that is approx0.1% of the bolometric luminosity of the object. Should the dust be part of the outflow, then these values are approx4x larger. The large mass flux and kinetic luminosity make this outflow a significant contributor to active galactic nucleus feedback processes.

  17. X-ray evidence for ultra-fast outflows in Seyfert galaxies

    NASA Astrophysics Data System (ADS)

    Tombesi, Francesco; Braito, Valentina; Reeves, James; Cappi, Massimo; Dadina, Mauro

    2012-07-01

    X-ray evidence for massive, highly ionized, ultra-fast outflows (UFOs) has been recently reported in a number of AGNs through the detection of blue-shifted Fe XXV/XXVI absorption lines. We present the results of a comprehensive spectral analysis of a large sample of 42 local Seyferts observed with XMM-Newton. Similar results are also obtained from a Suzaku analysis of 5 radio galaxies. We find that UFOs are common phenomena, being present in >40% of the sources. Their outflow velocity distribution is in the range ˜0.03--0.3c, with mean value of ˜0.14c. The ionization parameter is very high, in the range logξ˜3--6 erg~s^{-1}~cm, and the associated column densities are also large, in the range ˜10^{22}--10^{24} cm^{-2}. Their location is constrained at ˜0.0003--0.03pc (˜10^2--10^4 r_s) from the central black hole, consistent with what is expected for accretion disk winds/outflows. The mass outflow rates are in the interval ˜0.01--1M_{⊙}~yr^{-1}. The associated mechanical power is also high, in the range ˜10^{43}--10^{45} erg/s, which indicates that UFOs are capable to provide a significant contribution to the AGN cosmological feedback.

  18. X-ray Evidence for Ultra-Fast Outflows in Local AGNs

    NASA Astrophysics Data System (ADS)

    Tombesi, F.; Cappi, M.; Sambruna, R. M.; Reeves, J. N.; Reynolds, C. S.; Braito, V.; Dadina, M.

    2012-08-01

    X-ray evidence for ultra-fast outflows (UFOs) has been recently reported in a number of local AGNs through the detection of blue-shifted Fe XXV/XXVI absorption lines. We present the results of a comprehensive spectral analysis of a large sample of 42 local Seyferts and 5 Broad-Line Radio Galaxies (BLRGs) observed with XMM-Newton and Suzaku. We detect UFOs in ga 40% of the sources. Their outflow velocities are in the range ˜ 0.03-0.3c, with a mean value of ˜ 0.14c. The ionization is high, in the range logℰ ˜3-6rm erg s-1 cm, and also the associated column densities are large, in the interval ˜ 1022-1024rm cm-2. Overall, these results point to the presence of highly ionized and massive outflowing material in the innermost regions of AGNs. Their variability and location on sub-pc scales favor a direct association with accretion disk winds/outflows. This also suggests that UFOs may potentially play a significant role in the AGN cosmological feedback besides jets, and their study can provide important clues on the connection between accretion disks, winds, and jets.

  19. Shining a light on star formation driven outflows: the physical conditions within galactic outflows

    NASA Astrophysics Data System (ADS)

    Chisholm, John P.; Tremonti, Christina A.; Leitherer, Claus; Wofford, Aida; Chen, Yanmei

    2016-01-01

    Stellar feedback drives energy and momentum into the surrounding gas, which drives gas and metals out of galaxies through a galactic outflow. Unfortunately, galactic outflows are difficult to observe and characterize because they are extremely diffuse, and contain gas at many different temperatures. Here we present results from a sample of 37 nearby (z < 0.27) star forming galaxies observed in the ultraviolet with the Cosmic Origins Spectrograph on the Hubble Space Telescope. The sample covers over three decades in stellar mass and star formation rate, probing different morphologies such as dwarf irregulars and high-mass merging systems. Using four different UV absorption lines (O I, Si II, Si III and Si IV) that trace a wide range of temperatures (ionization potentials between 13.6 eV and 45 eV), we find shallow correlations between the outflow velocity or the equivalent width of absorption lines with stellar mass or star formation rate. Absorption lines probing different temperature phases have similar centroid velocities and line widths, indicating that they are comoving. Using the equivalent width ratios of the four different transitions, we find the ratios to be consistent with photo-ionized outflows, with moderately strong ionization parameters. By constraining the ionization mechanism we model the ionization fractions for each transition, but find the ionization fractions depend crucially on input model parameters. The shallow velocity scalings imply that low-mass galaxies launch outflows capable of escaping their galactic potential, while higher mass galaxies retain all of their gas, unless they undergo a merger.

  20. Characterizing Quasar Outflows II: The Incidence of the Highest Velocity Outflows

    NASA Astrophysics Data System (ADS)

    Stark, Michele A.; Ganguly, R.; Christenson, D. H.; Richmond, J. M.; Derseweh, J. A.; Robbins, J. M.; Townsend, S. L.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 11000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) measurements of UV emission line and continuum parameters. In an accompanying poster, we subjectively divide these quasars into four categories (broad absorption-line quasars, associated absorption-line quasars, reddened quasars, and unabsorbed/unreddened quasars). This subjective scheme is limited with regard to classifying narrow absorption-line systems (NALs). With single epoch, low dispersion SDSS spectra, we cannot distinguish between cosmologically intervening NALs, and intrinsic NALs that appear at large velocity offsets. In this poster, we tackle this uncertainty statistically by considering the incidence of both CIV and MgII NALs as a function of velocity, and how this distribution changes with quasar properties. We expect that absorption by intervening structures should not vary with quasar property. Other accompanying posters add photometry from rest-frame X-ray through the infrared (WISE) to complete the SED, which we utilize in these efforts. This material is based upon work supported by the National Aeronautics and Space Administration under

  1. EXPLOSIVE OUTFLOWS POWERED BY THE DECAY OF NON-HIERARCHICAL MULTIPLE SYSTEMS OF MASSIVE STARS: ORION BN/KL

    SciTech Connect

    Bally, John; Cunningham, Nathaniel J.; Moeckel, Nickolas; Burton, Michael G.; Smith, Nathan; Frank, Adam; Nordlund, Ake E-mail: ncunningham2@unl.edu E-mail: mgb@phys.unsw.edu.au E-mail: afrank@pas.rochester.edu

    2011-02-01

    The explosive Becklin-Neugebauer (BN)/Kleinman-Low (KL) outflow emerging from OMC1 behind the Orion Nebula may have been powered by the dynamical decay of a non-hierarchical multiple system {approx}500 years ago that ejected the massive stars I, BN, and source n, with velocities of about 10-30 km s{sup -1}. New proper-motion measurements of H{sub 2} features show that within the errors of measurement, the outflow originated from the site of stellar ejection. Combined with published data, these measurements indicate an outflow age of {approx}500 years, similar to the time since stellar ejection. The total kinetic energy of the ejected stars and the outflow is about 2 to 6 x 10{sup 47} erg. It is proposed that the gravitational potential energy released by the formation of a short-period binary, most likely source I, resulted in stellar ejection and powered the outflow. A scenario is presented for the formation of a compact, non-hierarchical multiple star system, its decay into an ejected binary and two high-velocity stars, and launch of the outflow. Three mechanisms may have contributed to the explosion in the gas: (1) unbinding of the circumcluster envelope following stellar ejection, (2) disruption of circumstellar disks and high-speed expulsion of the resulting debris during the final stellar encounter, and (3) the release of stored magnetic energy. Plausible protostellar disk end envelope properties can produce the observed outflow mass, velocity, and kinetic energy distributions. The ejected stars may have acquired new disks by fall-back or Bondi-Hoyle accretion with axes roughly orthogonal to their velocities. The expulsion of gas and stars from OMC1 may have been driven by stellar interactions.

  2. Disks and Outflows Around Young Stars

    NASA Astrophysics Data System (ADS)

    Beckwith, Steven; Staude, Jakob; Quetz, Axel; Natta, Antonella

    The subject of the book, the ubiquitous circumstellar disks around very young stars and the corresponding jets of outflowing matter, has recently become one of the hottest areas in astrophysics. The disks are thought to be precursors to planetary systems, and the outflows are thought to be a necessary phase in the formation of a young star, helping the star to get rid of angular momentum and energy as it makes its way onto the main sequence. The possible connections to planetary systems and stellar astrophysics makes these topics especially broad, appealing to generalists and specialists alike. The CD not only contains papers that could not be printed in the book but allows the authors to include a fair amount of data, often displayed as color images. The CD-ROM contains all the contributions printed in the corresponding book (Lecture Notes in Physics Vol. 465) and, in addition, those presented exclusively in digital form. Each contribution consists of a file in portable document format (PDF). The electronic version allows full-text searching within each file using Adobe's Acrobat Reader providing instructions for installation on Unix (Sun), PC and Macintosh computers, respectively. All contributions can be printed out; the color diagrams and color frames, which are printed in black and white in the book, can be viewed in color on screen.

  3. Simulating galactic outflows with kinetic supernova feedback

    NASA Astrophysics Data System (ADS)

    Dalla Vecchia, Claudio; Schaye, Joop

    2008-07-01

    Feedback from star formation is thought to play a key role in the formation and evolution of galaxies, but its implementation in cosmological simulations is currently hampered by a lack of numerical resolution. We present and test a subgrid recipe to model feedback from massive stars in cosmological smoothed particle hydrodynamics simulations. The energy is distributed in kinetic form among the gas particles surrounding recently formed stars. The impact of the feedback is studied using a suite of high-resolution simulations of isolated disc galaxies embedded in dark haloes with total mass 1010 and 1012h-1Msolar. We focus, in particular, on the effect of pressure forces on wind particles within the disc, which we turn off temporarily in some of our runs to mimic a recipe that has been widely used in the literature. We find that this popular recipe gives dramatically different results because (ram) pressure forces on expanding superbubbles determine both the structure of the disc and the development of large-scale outflows. Pressure forces exerted by expanding superbubbles puff up the disc, giving the dwarf galaxy an irregular morphology and creating a galactic fountain in the massive galaxy. Hydrodynamic drag within the disc results in a strong increase in the effective mass loading of the wind for the dwarf galaxy, but quenches much of the outflow in the case of the high-mass galaxy.

  4. Transparency parameters from relativistically expanding outflows

    SciTech Connect

    Bégué, D.; Iyyani, S.

    2014-09-01

    In many gamma-ray bursts a distinct blackbody spectral component is present, which is attributed to the emission from the photosphere of a relativistically expanding plasma. The properties of this component (temperature and flux) can be linked to the properties of the outflow and have been presented in the case where there is no sub-photospheric dissipation and the photosphere is in coasting phase. First, we present the derivation of the properties of the outflow for finite winds, including when the photosphere is in the accelerating phase. Second, we study the effect of localized sub-photospheric dissipation on the estimation of the parameters. Finally, we apply our results to GRB 090902B. We find that during the first epoch of this burst the photosphere is most likely to be in the accelerating phase, leading to smaller values of the Lorentz factor than the ones previously estimated. For the second epoch, we find that the photosphere is likely to be in the coasting phase.

  5. Magnetospheric and Thermospheric Influence on Ionospheric Outflow

    NASA Astrophysics Data System (ADS)

    Garcia-Sage, K.; Moore, T. E.; Mitchell, E. J.; Olson, D. K.

    2013-12-01

    The Fast Auroral SnapshoT (FAST) small explorer has been used extensively to study ionospheric outflow. Past research has used particle and field data to examine the contemporaneous transfer of electromagnetic energy and particle flow downward from the magnetosphere and upward from the ionosphere. Single event studies published by Strangeway et al. [2005] and Brambles et al. [2011, Supporting Online Material] showed that downward electromagnetic energy and particle flow into the ionosphere are correlated with the upward flow of ions out of the ionosphere. It is expected, however, that this correlation will be affected by circumstances that are unique to each specific event, including but not limited to the outflow location (cusp or nightside), preconditioning due to prior geomagnetic activity, and thermospheric neutral densities. Although knowledge of the thermospheric neutral density is usually unavailable, data from the CHAllenging Minisatellite Payload (CHAMP) is able to provide insight into thermospheric populations at altitudes of about 400 km for a few select events. We expand on the previously-mentioned studies by looking at FAST particle and field data for additional events, and we further examine the influence of thermospheric neutral populations, based on CHAMP data.

  6. Viruses, schizophrenia, and bipolar disorder.

    PubMed Central

    Yolken, R H; Torrey, E F

    1995-01-01

    The hypothesis that viruses or other infectious agents may cause schizophrenia or bipolar disorder dates to the 19th century but has recently been revived. It could explain many clinical, genetic, and epidemiologic aspects of these diseases, including the winter-spring birth seasonality, regional differences, urban birth, household crowding, having an older sibling, and prenatal exposure to influenza as risk factors. It could also explain observed immunological changes such as abnormalities of lymphocytes, proteins, autoantibodies, and cytokines. However, direct studies of viral infections in individuals with these psychiatric diseases have been predominantly negative. Most studies have examined antibodies in blood or cerebrospinal fluid, and relatively few studies have been done on viral antigens, genomes, cytopathic effect on cell culture, and animal transmission experiments. Viral research on schizophrenia and bipolar disorder is thus comparable to viral research on multiple sclerosis and Parkinson's disease: an attractive hypothesis with scattered interesting findings but no clear proof. The application of molecular biological techniques may allow the identification of novel infectious agents and the associations of these novel agents with serious mental diseases. PMID:7704891

  7. SPITZER OBSERVATIONS OF BOW SHOCKS AND OUTFLOWS IN RCW 38

    SciTech Connect

    Winston, E.; Wolk, S. J.; Bourke, T. L.; Spitzbart, B.; Megeath, S. T.; Gutermuth, R.

    2012-01-10

    We report Spitzer observations of five newly identified bow shocks in the massive star-forming region RCW 38. Four are visible at Infrared Array Camera (IRAC) wavelengths, the fifth is only visible at 24 {mu}m. Chandra X-ray emission indicates that winds from the central O5.5 binary, IRS 2, have caused an outflow to the northeast and southwest of the central subcluster. The southern lobe of hot ionized gas is detected in X-rays; shocked gas and heated dust from the shock front are detected with Spitzer at 4.5 and 24 {mu}m. The northern outflow may have initiated the present generation of star formation, based on the filamentary distribution of the protostars in the central subcluster. Further, the bow-shock driving star, YSO 129, is photo-evaporating a pillar of gas and dust. No point sources are identified within this pillar at near- to mid-IR wavelengths. We also report on IRAC 3.6 and 5.8 {mu}m observations of the cluster DBS2003-124, northeast of RCW 38, where 33 candidate young stellar objects (YSOs) are identified. One star associated with the cluster drives a parsec-scale jet. Two Herbig-Haro objects associated with the jet are visible at IRAC and Multiband Imaging Photometer for Spitzer (MIPS) wavelengths. The jet extends over a distance of {approx}3 pc. Assuming a velocity of 100 km s{sup -1} for the jet material gives an age of 3 Multiplication-Sign 10{sup 4} yr, indicating that the star (and cluster) are likely to be very young, with a similar or possibly younger age than RCW 38, and that star formation is ongoing in the extended RCW 38 region.

  8. Shocks in nova outflows. II. Synchrotron radio emission

    NASA Astrophysics Data System (ADS)

    Vlasov, Andrey; Vurm, Indrek; Metzger, Brian D.

    2016-08-01

    The discovery of GeV gamma-rays from classical novae indicates that shocks and relativistic particle acceleration are energetically key in these events. Further evidence for shocks comes from thermal keV X-ray emission and an early peak in the radio light curve on a timescale of months with a brightness temperature which is too high to result from freely expanding photo-ionized gas. Paper I developed a one dimensional model for the thermal emission from nova shocks. This work concluded that the shock-powered radio peak cannot be thermal if line cooling operates in the post-shock gas at the rate determined by collisional ionization equilibrium. Here we extend this calculation to include non-thermal synchrotron emission. Applying our model to three classical novae, we constrain the amplification of the magnetic field ɛB and the efficiency ɛe of accelerating relativistic electrons of characteristic Lorentz factor γ ˜ 100. If the shocks are radiative (low velocity v_sh ≲ 1000 km s-1) and cover a large solid angle of the nova outflow, as likely characterize those producing gamma-rays, then values of ɛe ˜ 0.01 - 0.1 are required to achieve the peak radio brightness for ɛB = 10-2. Such high efficiencies exclude secondary pairs from pion decay as the source of the radio-emitting particles, instead favoring the direct acceleration of electrons at the shock. If the radio-emitting shocks are instead adiabatic (high velocity), as likely characterize those responsible for the thermal X-rays, then much higher brightness temperatures are possible, allowing the radio-emitting shocks to cover a smaller outflow solid angle.

  9. Bipolar lead-acid battery for hybrid vehicles

    NASA Astrophysics Data System (ADS)

    Saakes, M.; Woortmeijer, R.; Schmal, D.

    Within the framework of the European project bipolar lead-acid power source (BILAPS), a new production route is being developed for the bipolar lead-acid battery. The performance targets are 500 W kg -1, 30 Wh kg -1 and 100 000 power-assist life cycles (PALCs). The operation voltage of the battery can be, according to the requirements, 12, 36 V or any other voltage. Tests with recently developed 4 and 12 V prototypes, each of 30 Ah capacity have demonstrated that the PALC can be operated using 10 C discharge and 9 C charge peaks. The tests show no overvoltage or undervoltage problems during three successive test periods of 16 h with 8 h rest in between. The temperature stabilizes during these tests at 40-45 °C using a thermal-management system. The bipolar lead acid battery is operated at an initial 50% state-of-charge. During the tests, the individual cell voltages display only very small differences. Tests are now in progress to improve further the battery-management system, which has been developed at the cell level, during the period no PALCs are run in order to improve the hybrid behaviour of the battery. The successful tests show the feasibility of operating the bipolar lead-acid battery in a hybrid mode. The costs of the system are estimated to be much lower than those for nickel-metal-hydride or Li-ion based high-power systems. An additional advantage of the lead-acid system is that recycling of lead-acid batteries is well established.

  10. Ionised outflows in z ~ 2.4 quasar host galaxies

    NASA Astrophysics Data System (ADS)

    Carniani, S.; Marconi, A.; Maiolino, R.; Balmaverde, B.; Brusa, M.; Cano-Díaz, M.; Cicone, C.; Comastri, A.; Cresci, G.; Fiore, F.; Feruglio, C.; La Franca, F.; Mainieri, V.; Mannucci, F.; Nagao, T.; Netzer, H.; Piconcelli, E.; Risaliti, G.; Schneider, R.; Shemmer, O.

    2015-08-01

    Aims: Outflows driven by active galactic nuclei (AGN) are invoked by galaxy evolutionary models to quench star formation and to explain the origin of the relations observed locally between super-massive black holes and their host galaxies. We here aim to detect extended ionised outflows in luminous quasars, where we expect the highest activity both in star formation and in black-hole accretion. Currently, there are only a few studies based on spatially resolved observations of outflows at high redshift, z > 2. Methods: We analysed a sample of six luminous (L > 1047 erg/s) quasars at z ~ 2.4, observed in H-band using the near-IR integral field spectrometer SINFONI at the VLT. We performed a kinematic analysis of the [Oiii] emission line at λ = 5007 Å. Results: We detect fast, spatially extended outflows in five out of six targets. [Oiii]λ5007 has a complex gas kinematic, with blue-shifted velocities of a few hundreds of km s-1 and line widths up to 1500 km s-1. Using the spectroastrometric method, we infer a size of the ionised outflows of up to ~2 kpc. The properties of the ionised outflows, mass outflow rate, momentum rate, and kinetic power, are correlated with the AGN luminosity. The increase in outflow rate with increasing AGN luminosity is consistent with the idea that a luminous AGN pushes away the surrounding gas through fast outflows that are driven by radiation pressure, which depends on the emitted luminosity. Conclusions: We derive mass outflow rates of about 6-700 M⊙ yr-1 for our sample, which are lower than those observed in molecular outflows. The physical properties of ionised outflows show dependences on AGN luminosity that are similar to those of molecular outflows, but indicate that the mass of ionised gas is lower than that of molecular outflows. Alternatively, this discrepancy between ionised and molecular outflows could be explained with different acceleration mechanisms. Based on Observations collected at the European Organisation for

  11. Measurement of Outflow Facility Using iPerfusion

    PubMed Central

    Sherwood, Joseph M.; Reina-Torres, Ester; Bertrand, Jacques A.; Rowe, Barnaby; Overby, Darryl R.

    2016-01-01

    Elevated intraocular pressure (IOP) is the predominant risk factor for glaucoma, and reducing IOP is the only successful strategy to prevent further glaucomatous vision loss. IOP is determined by the balance between the rates of aqueous humour secretion and outflow, and a pathological reduction in the hydraulic conductance of outflow, known as outflow facility, is responsible for IOP elevation in glaucoma. Mouse models are often used to investigate the mechanisms controlling outflow facility, but the diminutive size of the mouse eye makes measurement of outflow technically challenging. In this study, we present a new approach to measure and analyse outflow facility using iPerfusion™, which incorporates an actuated pressure reservoir, thermal flow sensor, differential pressure measurement and an automated computerised interface. In enucleated eyes from C57BL/6J mice, the flow-pressure relationship is highly non-linear and is well represented by an empirical power law model that describes the pressure dependence of outflow facility. At zero pressure, the measured flow is indistinguishable from zero, confirming the absence of any significant pressure independent flow in enucleated eyes. Comparison with the commonly used 2-parameter linear outflow model reveals that inappropriate application of a linear fit to a non-linear flow-pressure relationship introduces considerable errors in the estimation of outflow facility and leads to the false impression of pressure-independent outflow. Data from a population of enucleated eyes from C57BL/6J mice show that outflow facility is best described by a lognormal distribution, with 6-fold variability between individuals, but with relatively tight correlation of facility between fellow eyes. iPerfusion represents a platform technology to accurately and robustly characterise the flow-pressure relationship in enucleated mouse eyes for the purpose of glaucoma research and with minor modifications, may be applied in vivo to mice, as

  12. Bipolar plates for PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Middelman, E.; Kout, W.; Vogelaar, B.; Lenssen, J.; de Waal, E.

    The bipolar plates are in weight and volume the major part of the PEM fuel cell stack, and are also a significant contributor to the stack costs. The bipolar plate is therefore a key component if power density has to increase and costs must come down. Three cell plate technologies are expected to reach targeted cost price levels, all having specific advantages and drawbacks. NedStack has developed a conductive composite materials and a production process for fuel cell plates (bipolar and mono-polar). The material has a high electric and thermal conductivity, and can be processed into bipolar plates by a proprietary molding process. Process cycle time has been reduced to less than 10 s, making the material and process suitable for economical mass production. Other development work to increase material efficiency resulted in thin bipolar plates with integrated cooling channels, and integrated seals, and in two-component bipolar plates. Total thickness of the bipolar plates is now less than 3 mm, and will be reduced to 2 mm in the near future. With these thin integrated plates it is possible to increase power density up to 2 kW/l and 2 kW/kg, while at the same time reducing cost by integrating other functions and less material use.

  13. Brief Report: A Family Risk Study Exploring Bipolar Spectrum Problems and Cognitive Biases in Adolescent Children of Bipolar Parents

    ERIC Educational Resources Information Center

    Espie, Jonathan; Jones, Steven H.; Vance, Yvonne H.; Tai, Sara J.

    2012-01-01

    Children of parents with bipolar disorder are at increased risk of bipolar spectrum diagnoses. This cross-sectional study explores cognitive factors in the prediction of vulnerability to bipolar disorder. Adolescents at high-risk (with a parent with bipolar disorder; n = 23) and age and gender matched adolescents (n = 24) were recruited. Parent…

  14. VLT/MUSE view of the highly ionized outflow cones in the nearby starburst ESO338-IG04

    NASA Astrophysics Data System (ADS)

    Bik, A.; Östlin, G.; Hayes, M.; Adamo, A.; Melinder, J.; Amram, P.

    2015-04-01

    Context. The Lyα line is an important diagnostic for star formation at high redshift, but interpreting its flux and line profile is difficult because of the resonance nature of Lyα. Trends between the escape of Lyα photons and dust and properties of the interstellar medium (ISM) have been found, but detailed comparisons between Lyα emission and the properties of the gas in local high-redshift analogs are vital for understanding the relation between Lyα emission and galaxy properties. Aims: For the first time, we can directly infer the properties of the ionized gas at the same location and similar spatial scales of the extended Lyα halo around the local Lyα emitter and Lyman-break galaxy analog ESO 338-IG04. Methods: We obtained VLT/MUSE integral field spectra. We used ionization parameter mapping of the [S ii]/[O iii] line ratio and the kinematics of Hα to study the ionization state and kinematics of the ISM of ESO 338-IG04. Results: The velocity map reveals two outflows, one toward the north, the other toward the south of ESO 338. The ionization parameter mapping shows that the entire central area of the galaxy is highly ionized by photons leaking from the H ii regions around the youngest star clusters. Three highly ionized cones have been identified, of which one is associated with an outflow detected in the Hα. We propose a scenario where the outflows are created by mechanical feedback of the older clusters, while the highly ionized gas is caused by the hard ionizing photons emitted by the youngest clusters. A comparison with the Lyα map shows that the (approximately bipolar) asymmetries observed in the Lyα emission are consistent with the base of the outflows detected in Hα. No clear correlation with the ionization cones is found. Conclusions: The mechanical and ionization feedback of star clusters significantly changes the state of the ISM by creating ionized cones and outflows. The comparison with Lyα suggests that especially the outflows could

  15. Recognising Bipolar Disorders in Primary Care.

    PubMed

    Dietch, Daniel

    2015-09-01

    Bipolar disorder, previously called 'Manic-depression', is a complex group of conditions characterised by recurrent changes in mood and energy. Crucially, the intensity and duration of these changes go beyond normal fluctuations and personality traits. Bipolar Disorder is a mental health disorder, but physical health manifestations (Smith 2013, Westman 2013, Fagiolini 2008, Young 2013) and complications are just as important. GPs have a key role in the recognition and management, in conjunction with secondary care colleagues. Diagnosis is often difficult and may take several years (Smith 2011, Angst 2005, Manning 2010), because patients usually seek help for anxiety, depression or fatigue, not hypomania/mania, which they may not recognise. Individuals with a first episode of mania are more likely to present directly to secondary care, sometimes via a third party alerting the emergency services. There is also debate around the classification, diagnosis and treatment of individuals with brief and milder mood changes ('bipolar spectrum disorder') (Faravelli 2009, Spence 2011). In the UK, the recent NICE Guidelines (2014) 1 only included Bipolar I and Bipolar II for these reasons. A particular challenge for GPs is that whilst most people who have Bipolar Disorder (and especially Bipolar II) are depressed, most people with depression within a Primary Care setting do not have Bipolar Disorder. Thus, a brief pragmatic screen is recommended in Primary care: ask about a family history of Bipolar Disorder and screen for a history of mania/hypomania in individuals with anxiety, depression or irritability, especially if there are recurrent episodes, suicidal thoughts or a previous suicide attempt. For suspected cases, formal diagnosis should not be made within Primary Care but individuals should be referred for Psychiatric assessment, ideally to a Mood Disorders specialist. PMID:26417759

  16. Characterizing Quasar Outflows IV: Regulating Outflows Through X-ray and EUV Absorption

    NASA Astrophysics Data System (ADS)

    Derseweh, Jeffrey; Ganguly, R.; Richmond, J. M.; Stark, M. A.; Christenson, D. H.; Robbins, J. M.; Townsend, S. L.

    2012-05-01

    Galaxy evolution models have shown that quasars are a crucial ingredient in the evolution of massive galaxies. Outflows play a key role in the story of quasars and their host galaxies, by helping regulate the accretion process, the star-formation rate and mass of the host galaxy (i.e., feedback). The prescription for modeling outflows as a contributor to feedback requires knowledge of the outflow velocity, geometry, and column density. In particular, we need to understand how these depend on physical parameters and how much is determined stochastically (and with what distribution). For this purpose, we are examining a sample of 11000 z=1.7-2.0 quasars from the Sloan Digital Sky Survey. This redshift range permits the following from the SDSS spectra: (1) separation of objects that do and do not exhibit outflows; (2) classification/measurement of outflow properties (ionization, velocity, velocity width); and (3) measurements of UV emission line and continuum parameters. In this poster, we add photometry from the GALEX All-sky imaging survey, as well as the Chandra and ROSAT archives. These provide coverage of the rest-frame extreme ultraviolet, and soft X-ray bands. In an accompanying poster, we have subjectively divided these quasars into four categories: broad absorption-line quasars (2700 objects), associated absorption-line quasars (1700 objects), reddened quasars (160 objects), and unabsorbed/unreddened quasars (6300 objects). We are interested in testing the radiative-driving hypothesis that requires a suppression of X-ray flux in order to transfer momentum efficiently to the UV-absorbing gas. Hence, we explore how absorption in both the extreme ultraviolet and the soft X-ray bands correlate with properties of the UV outflows, quasar property, and changes in SED shape. This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. 09-ADP09-0016 issued through the Astrophysics Data Analysis Program and by Chandra

  17. Reoperation for left ventricular outflow tract obstruction after repair of atrioventricular septal.

    PubMed

    Overman, David M

    2014-01-01

    Left ventricular outflow tract obstruction (LVOTO) is an important source of morbidity and mortality after repair of atrioventricular septal defect (AVSD). The intrinsic anatomy of the left ventricular outflow tract in AVSD is complex and predisposes to the development of LVOTO. LVOTO after repair of AVSD usually involves multiple levels and sources of obstruction, and surgical intervention must address each component of the obstruction. This includes fibromuscular obstruction, septal hypertrophy, and valve related sources of obstruction. Special attention is also directed to the anterolateral muscle bundle of the left ventricle, a well defined but under recognized feature of the left ventricular outflow tract in AVSD. It is present in all patients with AVSD, and resection of a hypertrophic anterolateral muscle bundle of the left ventricle should be incorporated in all operations for LVOTO after repair of AVSD. LVOTO after repair of AVSD has several unique features that must be taken into consideration to maximize outcome after surgical intervention. These include anatomic factors, technical aspects of surgical intervention, and proper selection of the operation used for relief of LVOTO. PMID:24725716

  18. SEU In An Advanced Bipolar Integrated Circuit

    NASA Technical Reports Server (NTRS)

    Zoutendyk, John A.; Secrest, Elaine C.; Berndt, Dale F.

    1989-01-01

    Report summarizes investigation of single-event upsets (SEU) in bipolar integrated-circuit set of flip-flops (memory cells). Device tested made by advanced digital bipolar silicon process of Honeywell, Inc. Circuit chip contained 4 cells. Construction enabled study of effect of size on SEU behavior. Each cell externally biased so effect of bias current on SEU behavior. Results of study provides important information for optimal design of devices fabricated using buried-layer bipolar process operating in heavy-ion SEU environments. Designers use information to provide required levels of suppression of SEU in specific applications via combinations of size and/or cell-current scaling.

  19. Fueling active galactic nuclei. II. Spatially resolved molecular inflows and outflows

    SciTech Connect

    Davies, R. I.; Erwin, P.; Burtscher, L.; Lin, M.; Orban de Xivry, G.; Rosario, D. J.; Schnorr-Müller, A.; Maciejewski, W.; Hicks, E. K. S.; Emsellem, E.; Dumas, G.; Malkan, M. A.; Müller-Sánchez, F.; Tran, A.

    2014-09-10

    We analyze the two-dimensional distribution and kinematics of the stars as well as molecular and ionized gas in the central few hundred parsecs of five active and five matched inactive galaxies. The equivalent widths of the Brγ line indicate that there is no ongoing star formation in their nuclei, although recent (terminated) starbursts are possible in the active galaxies. The stellar velocity fields show no signs of non-circular motions, while the 1-0 S(1) H{sub 2} kinematics exhibit significant deviations from simple circular rotation. In the active galaxies the H{sub 2} kinematics reveal inflow and outflow superimposed on disk rotation. Steady-state circumnuclear inflow is seen in three active galactic nuclei (AGNs), and hydrodynamical models indicate it can be driven by a large-scale bar. In three of the five AGNs, molecular outflows are spatially resolved. The outflows are oriented such that they intersect, or have an edge close to, the disk, which may be the source of molecular gas in the outflow. The relatively low speeds imply the gas will fall back onto the disk, and with moderate outflow rates, they will have only a local impact on the host galaxy. H{sub 2} was detected in two inactive galaxies. These exhibit chaotic circumnuclear dust morphologies and have molecular structures that are counter-rotating with respect to the main gas component, which could lead to gas inflow in the near future. In our sample, all four galaxies with chaotic dust morphology in the circumnuclear region exist in moderately dense groups with 10-15 members where accretion of stripped gas can easily occur.

  20. Suzaku Discovery of Ultra-fast Outflows in Radio-loud AGN

    NASA Astrophysics Data System (ADS)

    Sambruna, Rita M.; Tombesi, F.; Reeves, J.; Braito, V.; Gofford, J.; Cappi, M.

    2010-03-01

    We present the results of an analysis of the 3.5--10.5 keV spectra of five bright Broad-Line Radio Galaxies (BLRGs) using proprietary and archival Suzaku observations. In three sources -- 3C 111, 3C 120, and 3C 390.3 -- we find evidence, for the first time in a radio-loud AGN, for absorption features at observed energies 7 keV and 8--9 keV, with high significance according to both the F-test and extensive Monte Carlo simulations (99% or larger). In the remaining two BLRGs, 3C 382 and 3C 445, there is no evidence for such absorption features in the XIS spectra. If interpreted as due to Fe XXV and/or Fe XXVI K-shell resonance lines, the absorption features in 3C 111, 3C 120, and 3C 390.3 imply an origin from an ionized gas outflowing with velocities in the range v 0.04-0.15c, reminiscent of Ultra-Fast Outflows (UFOs) previously observed in radio-quiet Seyfert galaxies. A fit with specific photoionization models gives ionization parameters log ξ 4--5.6 erg s-1 cm and column densities of NH 1022-23 cm-2, similar to the values observed in Seyferts. Based on light travel time arguments, we estimate that the UFOs in the three BLRGs are located within 20--500 gravitational radii from the central black hole, and thus most likely are connected to disk winds/outflows. Our estimates show that the UFOs mass outflow rate is comparable to the accretion rate and their kinetic energy a significant fraction of the AGN bolometric luminosity, making these outflows significant for the global energetic of these systems, in particular for mechanisms of jet formation.

  1. HiRes Deconvolution of Outflow Cavities Imaged by Spitzer

    NASA Astrophysics Data System (ADS)

    Velusamy, Thangasamy; Langer, W. D.; Marsh, K. A.

    2007-05-01

    Circumstellar outflows are believed to play a central role in the dispersal of the envelope and the ejection of angular momentum from protostars and their associated disks. The opening angle of the outflow is an important indicator of the time evolution of the outflow and its effects on infall and accretion. The scattered light emission escaping out the outflow cavities can be observed in the deep Spitzer images in the IRAC bands. We present examples of HiRes deconvolved Spitzer IRAC images of outflow cavities. HiRes achieves sub-arcsec resolution (< 0.8") for IRAC channels at 3.6 and 4.5 microns and 1" at 5.8 and 8 microns. Furthermore, HiRes deconvolution removes all the diffraction lobes producing cleaner looking narrow image of the protostar and nearby bright stars. Thus HiRes analysis improves our ability to trace the outflow cavities. We also present geometric models of the outflow (inclination and deprojected opening angles) derived by fitting SEDs and images of the outflow cavities. This work was performed by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration

  2. Collective outflow from a small multiple stellar system

    SciTech Connect

    Peters, Thomas; Klaassen, Pamela D.; Mac Low, Mordecai-Mark; Schrön, Martin; Klessen, Ralf S.; Federrath, Christoph; Smith, Michael D.

    2014-06-10

    The formation of high-mass stars is usually accompanied by powerful protostellar outflows. Such high-mass outflows are not simply scaled-up versions of their lower-mass counterparts, since observations suggest that the collimation degree degrades with stellar mass. Theoretically, the origins of massive outflows remain open to question because radiative feedback and fragmentation of the accretion flow around the most massive stars, with M > 15 M {sub ☉}, may impede the driving of magnetic disk winds. We here present a three-dimensional simulation of the early stages of core fragmentation and massive star formation that includes a subgrid-scale model for protostellar outflows. We find that stars that form in a common accretion flow tend to have aligned outflow axes, so that the individual jets of multiple stars can combine to form a collective outflow. We compare our simulation to observations with synthetic H{sub 2} and CO observations and find that the morphology and kinematics of such a collective outflow resembles some observed massive outflows, such as Cepheus A and DR 21. We finally compare physical quantities derived from simulated observations of our models to the actual values in the models to examine the reliability of standard methods for deriving physical quantities, demonstrating that those methods indeed recover the actual values to within a factor of two to three.

  3. Ultra-Fast Outflows in Radio-Loud AGN: New Constraints on Jet-Disk Connection

    NASA Astrophysics Data System (ADS)

    Sambruna, Rita

    There is strong observational and theoretical evidence that outflows/jets are coupled to accretion disks in black hole accreting systems, from Galactic to extragalactic sizes. While in radio-quiet AGN there is ample evidence for the presence of Ultra-Fast Outflows (UFOs) from the presence of blue-shifted absorption features in their 4-10~keV spectra, sub-relativistic winds are expected on theoretical basis in radio-loud AGN but have not been observed until now. Our recent Suzaku observations of 5 bright Broad- Line Radio Galaxies (BLRGs, the radio-loud counterparts of Seyferts) has started to change this picture. We found strong evidence for UFOs in 3 out of 5 BLRGs, with ionization parameters, column densities, and velocities of the absorber similar to Seyferts. Moreover, the outflows in BLRGs are likely to be energetically very significant: from the Suzaku data of the three sources, outflow masses similar to the accretion masses and kinetic energies of the wind similar to the X-ray luminosity and radio power of the jet are inferred. Clearly, UFOs in radio-loud AGN represent a new key ingredient to understand their central engines and in particular, the jet-disk linkage. Our discovery of UFOs in a handful of BLRGs raises the questions of how common disk winds are in radio-loud AGN, what the absorber physical and dynamical characteristics are, and what is the outflow role in broader picture of galaxy-black hole connection for radio sources, i.e., for large-scale feedback models. To address these and other issues, we propose to use archival XMM-Newton and Suzaku spectra to search for Ultra-Fast Outflows in a large number of radio sources. Over a period of two years, we will conduct a systematic, uniform analysis of the archival X-ray data, building on our extensive experience with a similar previous project for Seyferts, and using robust analysis and statistical methodologies. As an important side product, we will also obtain accurate, self- consistent measurements

  4. The molecular gas content of the Pipe Nebula. I. Direct evidence of outflow-generated turbulence in B59?

    NASA Astrophysics Data System (ADS)

    Duarte-Cabral, A.; Chrysostomou, A.; Peretto, N.; Fuller, G. A.; Matthews, B.; Schieven, G.; Davis, G. R.

    2012-07-01

    quiescent gas and small number of protostars, allows the identification of specific regions where the outflows from the embedded sources interact the dense gas. Our study suggests that outflows are an important mechanism for injecting and sustaining supersonic turbulence at sub-parsec size scales. We find that less than half of the outflow energy is deposited as turbulent energy of the gas, however this turbulent energy is sufficient to slow down the collapse of the region.

  5. Mid-Infrared Spectropolarimetry of Molecular Cloud Sources: Magnetic Fields and Dust Properties

    NASA Astrophysics Data System (ADS)

    Wright, Christopher Mathew

    1994-12-01

    One of the earliest phases of the star formation process is the bipolar outflow. It is not presently understood how the outflow is generated, but a number of theories propose that a dynamically important magnetic field, embedded in the disk and acting in concert with rotation, is able to tap the gravitational potential well of the star plus disk system to drive material off the disk surface. Spectropolarimetric observations between 8 and 13 micrometers provide information on the chemical and physical nature of dust grains, as well as on the direction of the transverse (to the line-of-sight) component of an aligning magnetic field. In this thesis, such observations toward a selection of mainly high mass young stellar objects (YSO's) are presented. The field directions inferred from the polarization position angle are compared with the axes of disks and bipolar outflows associated with the sources. A strong correlation is found such that the field tends to lie in the plane of the disk, thereby providing support for the magnetic pressure mechanism for bipolar outflows. The observed field directions are also compared with the interstellar field configuration determined from optical polarization of field stars and obtained from the literature. Two distributions are observed, one in which the difference between the position angles of the two fields is less than 30 deg, and the other for which the difference is greater than 30 deg. The existence of the second group implies that the evolution of the YSO has a significant perturbing effect on its ambient magnetic field. Together with the disk field finding, the results are discussed in terms of the initial collapse phase of the molecular cloud in which the YSO is embedded, specifically whether the cloud was supercritical or subcritical. For instance, for two high mass objects, AFGL 2591 and AFGL 989, and one low mass object, SVS13, the source and interstellar fields, and interstellar field and disk major axes, are inclined

  6. Evidence of Particle Acceleration and Plasma Heating in Magnetic Reconnection Outflows in an Eruptive Solar Flare

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Chen, Q.; Petrosian, V.

    2013-07-01

    Where particle acceleration and plasma heating take place in relation to magnetic reconnection is a fundamental question for solar flares. We present here analysis of an M7.7 flare on 2012 July 19 observed by SDO/AIA and RHESSI that sheds new light on this question (Liu, Chen, & Petrosian, 2013, ApJ). Bi-directional outflows in forms of plasmoid ejections and contracting cusp-shaped loops originate between an erupting flux rope (Patsourakos et al. 2013, ApJ) and underlying flare loops at speeds of typically 200-300 km/s up to 1050 km/s. These outflows are associated with spatially separated double coronal X-ray sources with their centroid separation decreasing with energy. The highest temperature is located near the nonthermal X-ray loop-top source, well below the original heights of contracting cusps near the inferred reconnection site. These observations suggest that the primary loci of particle acceleration and plasma heating are in the reconnection outflow regions, rather than the reconnection site itself. We stress that models with this ingredient were proposed long ago (e.g., Forbes & Priest 1983) and backed by recent numerical simulations (e.g., Drake & Swisdak 2012), but solid observational evidence as presented here has been lacking. In addition, there is an initial ascent of the X-ray and EUV loop-top source prior to its recently recognized descent, which we ascribe to the interplay among multiple processes including the upward development of reconnection and the downward contractions of reconnected loops. The impulsive phase onset coincides with the rapid speed increases of the upward plasmoids, the individual loop shrinkages, and the overall loop-top descent, suggestive of an intimate relation of the energy release rate and the reconnection outflow speed.Abstract (2,250 Maximum Characters): Where particle acceleration and plasma heating take place in relation to magnetic reconnection is a fundamental question for solar flares. We present here analysis

  7. Simulation of Breach Outflow for Earthfill Dam

    NASA Astrophysics Data System (ADS)

    Razad, Azwin Zailti Abdul; Sabri Muda, Rahsidi; Mohd Sidek, Lariyah; Azia, Intan Shafilah Abdul; Hanum Mansor, Faezah; Yalit, Ruzaimei

    2013-06-01

    Dams have been built for many reasons such as irrigation, hydropower, flood mitigation, and water supply to support development for the benefit of human. However, the huge amount of water stored behind the dam can seriously pose adverse impacts to the downstream community should it be released due to unwanted dam break event. To minimise the potential loss of lives and property damages, a workable Emergency Response Plan is required to be developed. As part of a responsible dam owner and operator, TNB initiated a study on dam breach modelling for Cameron Highlands Hydroelectric Scheme to simulate the potential dam breach for Jor Dam. Prediction of dam breach parameters using the empirical equations of Froehlich and Macdonal-Langridge-Monopolis formed the basis of the modelling, coupled with MIKE 11 software to obtain the breach outflow due to Probable Maximum Flood (PMF). This paper will therefore discuss the model setup, simulation procedure and comparison of the prediction with existing equations.

  8. Functional Anatomy of the Outflow Facilities

    PubMed Central

    Pizzirani, Stefano; Gong, Haiyan

    2016-01-01

    The aqueous humor (AH) is the fluid that fills the anterior and posterior chambers of the eye. Its main roles are to provide nourishment and metabolic waste removal to active metabolic ocular structures that are avascular and to contribute maintaining a normal intraocular pressure (IOP) without altering the refractive status of the eye. Its composition and the fluid dynamics associated with its flow are voluble and undergo changes associated with age and disease. Of particular importance is that the resistance to the outflow of AH from the anterior chamber is influenced by morphologic, physiologic, and biochemical dynamic factors.1 Beside aqueous nutritional importance, its solutes also participate in establishing the anterior chamber associate immune deviation, and carry and distribute the different proteins and molecules that promote and direct tissue remodeling and changes in the anterior segment that are associated with both age and disease. PMID:26337760

  9. 'What controls aqueous humour outflow resistance?'.

    PubMed

    Johnson, Mark

    2006-04-01

    The bulk of aqueous humour outflow resistance is generated in or near the inner wall endothelium of Schlemm's canal in normal eyes, and probably also in glaucomatous eyes. Fluid flow through this region is controlled by the location of the giant vacuoles and pores found in cells of the endothelium of Schlemm's canal, but the flow resistance itself is more likely generated either in the extracellular matrix of the juxtacanalicular connective tissue or the basement membrane of Schlemm's canal. Future studies utilizing in vitro perfusion studies of inner wall endothelial cells may give insights into the process by which vacuoles and pores form in this unique endothelium and why inner wall pore density is greatly reduced in glaucoma. PMID:16386733

  10. FIRE simulations: galactic outflows and their consequences

    NASA Astrophysics Data System (ADS)

    Keres, Dusan; FIRE team

    2016-06-01

    We study gaseous outflows and their consequences in high-resolution galaxy formation simulations with explicit stellar feedback from the Feedback in Realistic Environments project. Collective, galaxy scale, effect of stellar feedback results in episodic ejections of large amount of gas and heavy elements into the circum-galactic medium. Gas ejection episodes follow strong bursts of star formation. Properties of galactic star formation and ejection episodes depend on galaxy mass and redshift and, together with gas infall and recycling, shape the evolution of the circum-galactic medium and galaxies. As a consequence, our simulated galaxies have masses, star formation histories and heavy element content in good agreement with the observed population of galaxies.

  11. Ice sculpture in the Martian outflow channels

    NASA Technical Reports Server (NTRS)

    Lucchitta, B. K.

    1982-01-01

    Viking Orbiter and terrestrial satellite images are examined at similar resolution to compare features of the Martian outflow channels with features produced by the movement of ice on earth, and many resemblances are found. These include the anastomoses, sinuosities, and U-shaped cross profiles of valleys; hanging valleys; linear scour marks on valley walls; grooves and ridges on valley floors; and the streamlining of bedrock highs. Attention is given to the question whether ice could have moved in the Martian environment. It is envisaged that springs or small catastrophic outbursts discharged fluids from structural outlets or chaotic terrains. These fluids built icings that may have grown into substantial masses and eventually flowed like glaciers down preexisting valleys. An alternative is that the fluids formed rivers or floods that in turn formed ice jams and consolidated into icy masses in places where obstacles blocked their flow.

  12. Searching for molecular outflows in hyperluminous infrared galaxies

    NASA Astrophysics Data System (ADS)

    Calderón, D.; Bauer, F. E.; Veilleux, S.; Graciá-Carpio, J.; Sturm, E.; Lira, P.; Schulze, S.; Kim, S.

    2016-08-01

    We present constraints on the molecular outflows in a sample of five hyperluminous infrared galaxies using Herschel observations of the OH doublet at 119 μm. We have detected the OH doublet in three cases: one purely in emission and two purely in absorption. The observed emission profile has a significant blueshifted wing suggesting the possibility of tracing an outflow. Out of the two absorption profiles, one seems to be consistent with the systemic velocity while the other clearly indicates the presence of a molecular outflow whose maximum velocity is about ˜1500 km s-1. Our analysis shows that this system is in general agreement with previous results on ultraluminous infrared galaxies and QSOs, whose outflow velocities do not seem to correlate with stellar masses or starburst luminosities (star formation rates). Instead, the galaxy outflow likely arises from an embedded active galactic nuclei.

  13. Myocardialization of the cardiac outflow tract

    NASA Technical Reports Server (NTRS)

    van den Hoff, M. J.; Moorman, A. F.; Ruijter, J. M.; Lamers, W. H.; Bennington, R. W.; Markwald, R. R.; Wessels, A.

    1999-01-01

    During development, the single-circuited cardiac tube transforms into a double-circuited four-chambered heart by a complex process of remodeling, differential growth, and septation. In this process the endocardial cushion tissues of the atrioventricular junction and outflow tract (OFT) play a crucial role as they contribute to the mesenchymal components of the developing septa and valves in the developing heart. After fusion, the endocardial ridges in the proximal portion of the OFT initially form a mesenchymal outlet septum. In the adult heart, however, this outlet septum is basically a muscular structure. Hence, the mesenchyme of the proximal outlet septum has to be replaced by cardiomyocytes. We have dubbed this process "myocardialization." Our immunohistochemical analysis of staged chicken hearts demonstrates that myocardialization takes place by ingrowth of existing myocardium into the mesenchymal outlet septum. Compared to other events in cardiac septation, it is a relatively late process, being initialized around stage H/H28 and being basically completed around stage H/H38. To unravel the molecular mechanisms that are responsible for the induction and regulation of myocardialization, an in vitro culture system in which myocardialization could be mimicked and manipulated was developed. Using this in vitro myocardialization assay it was observed that under the standard culture conditions (i) whole OFT explants from stage H/H20 and younger did not spontaneously myocardialize the collagen matrix, (ii) explants from stage H/H21 and older spontaneously formed extensive myocardial networks, (iii) the myocardium of the OFT could be induced to myocardialize and was therefore "myocardialization-competent" at all stages tested (H/H16-30), (iv) myocardialization was induced by factors produced by, most likely, the nonmyocardial component of the outflow tract, (v) at none of the embryonic stages analyzed was ventricular myocardium myocardialization-competent, and finally

  14. Bipolar Disorder: A Daughter's Experience.

    PubMed

    Khare, Satya Rashi

    2016-09-01

    My father suffered from bipolar disorder. His illness placed an enormous strain on our relationship which, for the most part, was filled with turbulence. Although our family physician played an integral role in supporting my parents throughout the disease, I did not receive the same support and suffered as a consequence. In this essay, I describe my father's manic and major depressive episodes, as well as my emotions that resulted from the experience. Treating mental illness goes beyond just treating the patient but rather encompasses the family as a whole. My relationship with my father may have been different had I learned effective coping strategies through the support of my family physician. PMID:27621165

  15. Antidepressant chronotherapeutics for bipolar depression.

    PubMed

    Benedetti, Francesco

    2012-12-01

    Chronotherapeutics refers to treatments based on the principles of circadian rhythm organization and sleep physiology, which control the exposure to environmental stimuli that act on biological rhythms, in order to achieve therapeutic effects in the treatment of psychiatric conditions. It includes manipulations of the sleep-wake cycle such as sleep deprivation and sleep phase advance, and controlled exposure to light and dark. The antidepressant effects of chronotherapeutics are evident in difficult-to-treat conditions such as bipolar depression, which has been associated with extremely low success rates of antidepressant drugs in naturalistic settings and with stable antidepressant response to chronotherapeutics in more than half of the patients. Recent advances in the study of the effects of chronotherapeutics on neurotransmitter systems, and on the biological clock machinery, allow us to pinpoint its mechanism of action and to transform it from a neglected or "orphan" treatment to a powerful clinical instrument in everyday psychiatric practice. PMID:23393416

  16. Composite substrate for bipolar electrodes

    DOEpatents

    Tekkanat, B.; Bolstad, J.J.

    1992-12-22

    Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the present invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process. 4 figs.

  17. Antidepressant chronotherapeutics for bipolar depression

    PubMed Central

    Benedetti, Francesco

    2012-01-01

    Chronotherapeutics refers to treatments based on the principles of circadian rhythm organization and sleep physiology, which control the exposure to environmental stimuli that act on biological rhythms, in order to achieve therapeutic effects in the treatment of psychiatric conditions. It includes manipulations of the sleep-wake cycle such as sleep deprivation and sleep phase advance, and controlled exposure to light and dark. The antidepressant effects of chronotherapeutics are evident in difficult-to-treat conditions such as bipolar depression, which has been associated with extremely low success rates of antidepressant drugs in naturalistic settings and with stable antidepressant response to chronotherapeutics in more than half of the patients. Recent advances in the study of the effects of chronotherapeutics on neurotransmitter systems, and on the biological clock machinery, allow us to pinpoint its mechanism of action and to transform it from a neglected or “orphan” treatment to a powerful clinical instrument in everyday psychiatric practice. PMID:23393416

  18. Composite substrate for bipolar electrodes

    DOEpatents

    Tekkanat, Bora; Bolstad, James J.

    1992-12-22

    Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the pesent invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process.

  19. Recent work on bipolar nebulae

    NASA Technical Reports Server (NTRS)

    Cohen, M.

    1983-01-01

    The results of recent studies of bipolar nebulae (BPN) using nebular-polarization mapping, spectropolarimetry, near-IR spectroscopy, far-IR photometry, and radio-maser and continuum observations are surveyed. The characteristics of several BPN of different evolutionary types are discussed and illustrated with spectra, model drawings, and maps. As shown in a Hertzsprung-Russell diagram of 19 BPN, this morphological class includes pre-main-sequence stars, red giants in transition to ordinary planetary nebulae, pre-white-dwarfs, a dust-shrouded carbon star, and a visual binary with a type-O primary. VLA 6-cm observations of the latter object, MWC 349, reveal a morphology similar to the optical structure of the Red Rectangle illuminated by HD 44179: it is suggested that equatorial dusty tori may occur commonly at different phases of stellar evolution, and hence that BPN may be relatively abundant, although short-lived, phenomena.

  20. Detection of a high brightness temperature radio core in the AGN-driven molecular outflow candidate NGC 1266

    NASA Astrophysics Data System (ADS)

    Nyland, K.; Alatalo, K.; Wrobel, J. M.; Young, L. M.; Morganti, R.; Davis, T. A.; de Zeeuw, P. T.; Deustua, S.; Bureau, M.

    2014-05-01

    We present new Karl G. Jansky Very Large Array (VLA) Hi absorption and Very Long Baseline Array (VLBA) continuum observations of the active galactic nucleus (AGN)-driven molecular outflow candidate NGC 1266. Although other well-known systems with molecular outflows may be driven by star formation in a central molecular disk, the molecular mass outflow rate reported in Alatalo et al. (2011) in NGC 1266 of 13 M⊙ year-1 exceeds star formation rate estimates from a variety of tracers. This suggests that an additional energy source, such as an AGN, may play a significant role in powering the outflow. Our high spatial resolution Hi absorption data reveal compact absorption against the radio continuum core co-located with the putative AGN, and the presence of a blueshifted spectral component re-affirms that gas is indeed flowing out of the system. Our VLBA observations at 1.65 GHz reveal one continuum source within the densest portion of the molecular gas, with a diameter d < 8 mas (1.2 pc), a radio power P rad = 1.48 × 1020 W Hz-1, and a brightness temperature T b > 1.5 × 107 K that is most consistent with an AGN origin. The radio continuum energetics implied by the compact VLBA source, as well as archival VLA continuum observations at lower spatial resolution, further support the possibility that the AGN in NGC 1266 could be driving the molecular outflow. These findings suggest that even low-level AGNs, with supermassive black hole masses similar to Sgr A*, may be able to launch massive outflows in their host galaxies.

  1. Detection of a High Brightness Temperature Radio Core in the Active-galactic-nucleus-driven Molecular Outflow Candidate NGC 1266

    NASA Astrophysics Data System (ADS)

    Nyland, Kristina; Alatalo, Katherine; Wrobel, J. M.; Young, Lisa M.; Morganti, Raffaella; Davis, Timothy A.; de Zeeuw, P. T.; Deustua, Susana; Bureau, Martin

    2013-12-01

    We present new high spatial resolution Karl G. Jansky Very Large Array (VLA) H I absorption and Very Long Baseline Array (VLBA) continuum observations of the active-galactic-nucleus-(AGN-)driven molecular outflow candidate NGC 1266. Although other well-known systems with molecular outflows may be driven by star formation (SF) in a central molecular disk, the molecular mass outflow rate of 13 M ⊙ yr-1 in NGC 1266 reported by Alatalo et al. exceeds SF rate estimates from a variety of tracers. This suggests that an additional energy source, such as an AGN, may play a significant role in powering the outflow. Our high spatial resolution H I absorption data reveal compact absorption against the radio continuum core co-located with the putative AGN, and the presence of a blueshifted spectral component re-affirms that gas is indeed flowing out of the system. Our VLBA observations at 1.65 GHz reveal one continuum source within the densest portion of the molecular gas, with a diameter d < 8 mas (1.2 pc), a radio power P rad = 1.48 × 1020 W Hz-1, and a brightness temperature T b > 1.5 × 107 K that is most consistent with an AGN origin. The radio continuum energetics implied by the compact VLBA source, as well as archival VLA continuum observations at lower spatial resolution, further support the possibility that the AGN in NGC 1266 could be driving the molecular outflow. These findings suggest that even low-level AGNs may be able to launch massive outflows in their host galaxies.

  2. Detection of a high brightness temperature radio core in the active-galactic-nucleus-driven molecular outflow candidate NGC 1266

    SciTech Connect

    Nyland, Kristina; Young, Lisa M.; Alatalo, Katherine; Wrobel, J. M.; Morganti, Raffaella; Davis, Timothy A.; De Zeeuw, P. T.; Deustua, Susana; Bureau, Martin

    2013-12-20

    We present new high spatial resolution Karl G. Jansky Very Large Array (VLA) H I absorption and Very Long Baseline Array (VLBA) continuum observations of the active-galactic-nucleus-(AGN-)driven molecular outflow candidate NGC 1266. Although other well-known systems with molecular outflows may be driven by star formation (SF) in a central molecular disk, the molecular mass outflow rate of 13 M {sub ☉} yr{sup –1} in NGC 1266 reported by Alatalo et al. exceeds SF rate estimates from a variety of tracers. This suggests that an additional energy source, such as an AGN, may play a significant role in powering the outflow. Our high spatial resolution H I absorption data reveal compact absorption against the radio continuum core co-located with the putative AGN, and the presence of a blueshifted spectral component re-affirms that gas is indeed flowing out of the system. Our VLBA observations at 1.65 GHz reveal one continuum source within the densest portion of the molecular gas, with a diameter d < 8 mas (1.2 pc), a radio power P {sub rad} = 1.48 × 10{sup 20} W Hz{sup –1}, and a brightness temperature T {sub b} > 1.5 × 10{sup 7} K that is most consistent with an AGN origin. The radio continuum energetics implied by the compact VLBA source, as well as archival VLA continuum observations at lower spatial resolution, further support the possibility that the AGN in NGC 1266 could be driving the molecular outflow. These findings suggest that even low-level AGNs may be able to launch massive outflows in their host galaxies.

  3. Miniature Bipolar Electrostatic Ion Thruster

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.

    2006-01-01

    The figure presents a concept of a bipolar miniature electrostatic ion thruster for maneuvering a small spacecraft. The ionization device in the proposed thruster would be a 0.1-micron-thick dielectric membrane with metal electrodes on both sides. Small conical holes would be micromachined through the membrane and electrodes. An electric potential of the order of a volt applied between the membrane electrodes would give rise to an electric field of the order of several mega-volts per meter in the submicron gap between the electrodes. An electric field of this magnitude would be sufficient to ionize all the molecules that enter the holes. In a thruster-based on this concept, one or more propellant gases would be introduced into such a membrane ionizer. Unlike in larger prior ion thrusters, all of the propellant molecules would be ionized. This thruster would be capable of bipolar operation. There would be two accelerator grids - one located forward and one located aft of the membrane ionizer. In one mode of operation, which one could denote the forward mode, positive ions leaving the ionizer on the backside would be accelerated to high momentum by an electric field between the ionizer and an accelerator grid. Electrons leaving the ionizer on the front side would be ejected into free space by a smaller accelerating field. The equality of the ion and electron currents would eliminate the need for an additional electron- or ion-emitting device to keep the spacecraft charge-neutral. In another mode of operation, which could denote the reverse mode, the polarities of the voltages applied to the accelerator grids and to the electrodes of the membrane ionizer would be the reverse of those of the forward mode. The reversal of electric fields would cause the ion and electrons to be ejected in the reverse of their forward mode directions, thereby giving rise to thrust in the direction opposite that of the forward mode.

  4. Development and Morphology of the Ventricular Outflow Tracts.

    PubMed

    Anderson, Robert H; Mori, Shumpei; Spicer, Diane E; Brown, Nigel A; Mohun, Timothy J

    2016-09-01

    It is customary, at the current time, to consider many, if not most, of the lesions involving the ventricular outflow tract in terms of conotruncal malformations. This reflects the introduction, in the early 1940s, of the terms conus and truncus to describe the components of the developing outflow tract. The definitive outflow tracts in the postnatal heart, however, possess three, rather than two, components. These are the intrapericardial arterial trunks, the arterial roots, and the subvalvar ventricular outflow tracts. Congenital lesions afflicting the arterial roots, however, are not currently considered to be conotruncal malformations. This suggests a lack of logic in the description of cardiac development and its use as a means of categorizing congenital malformations. It is our belief that the developing outflow tract, like the postnatal outflow tracts, can readily be described in tripartite fashion, with its distal, intermediate, and proximal components forming the primordiums of the postnatal parts. In this review, we present evidence obtained from developing mice and human hearts to substantiate this notion. We show that the outflow tract, initially with a common lumen, is divided into its aortic and pulmonary components by a combination of an aortopulmonary septum derived from the dorsal wall of the aortic sac and outflow tract cushions that spiral through its intermediate and proximal components. These embryonic septal structures, however, subsequently lose their septal functions as the outflow tracts develop their own discrete walls. We then compare the developmental findings with the anatomic arrangements seen postnatally in the normal human heart. We show how correlations with the embryologic findings permit logical analysis of the congenital lesions involving the outflow tracts. PMID:27587491

  5. Development and Morphology of the Ventricular Outflow Tracts

    PubMed Central

    Mori, Shumpei; Spicer, Diane E.; Brown, Nigel A.; Mohun, Timothy J.

    2016-01-01

    It is customary, at the current time, to consider many, if not most, of the lesions involving the ventricular outflow tract in terms of conotruncal malformations. This reflects the introduction, in the early 1940s, of the terms conus and truncus to describe the components of the developing outflow tract. The definitive outflow tracts in the postnatal heart, however, possess three, rather than two, components. These are the intrapericardial arterial trunks, the arterial roots, and the subvalvar ventricular outflow tracts. Congenital lesions afflicting the arterial roots, however, are not currently considered to be conotruncal malformations. This suggests a lack of logic in the description of cardiac development and its use as a means of categorizing congenital malformations. It is our belief that the developing outflow tract, like the postnatal outflow tracts, can readily be described in tripartite fashion, with its distal, intermediate, and proximal components forming the primordiums of the postnatal parts. In this review, we present evidence obtained from developing mice and human hearts to substantiate this notion. We show that the outflow tract, initially with a common lumen, is divided into its aortic and pulmonary components by a combination of an aortopulmonary septum derived from the dorsal wall of the aortic sac and outflow tract cushions that spiral through its intermediate and proximal components. These embryonic septal structures, however, subsequently lose their septal functions as the outflow tracts develop their own discrete walls. We then compare the developmental findings with the anatomic arrangements seen postnatally in the normal human heart. We show how correlations with the embryologic findings permit logical analysis of the congenital lesions involving the outflow tracts. PMID:27587491

  6. Modeling the Causal Regulation of Transversely Accelerated Ion (TAI) Outflows

    NASA Astrophysics Data System (ADS)

    Varney, R. H.; Wiltberger, M. J.; Zhang, B.; Schmitt, P.; Lotko, W.

    2013-12-01

    TAIs are generated by wave particle interactions driven by waves at temporal and spatial scales which are inaccessible in global coupled geospace models. So far attempts to include TAI outflows in global models have focused on the use of empirical correlations between observed outflow fluxes and various inputs such as DC Poynting flux, Alfvénic Poynting flux, and electron precipitation fluxes. These treatments ignore feedbacks between the outflow and the state of the ionosphere and assume the spatial and temporal distributions of the outflows are identical to those of their drivers. This work presents an alternative approach which can overcome these deficiencies while still being sufficiently computationally efficient to couple into a global modeling framework. TAIs are incorporated into a 3-D fluid model of the ionosphere and polar wind by modeling them as a separate fluid which obeys transport equations appropriate for monoenergetic conic distributions. The characteristics of the TAI outflow produced depend on the assumed transverse heating rates and the 'promotion rate' which connects the TAI fluid to the thermal O+ fluid. Using drivers extracted from runs of the Coupled Magnetosphere Ionosphere Thermosphere (CMIT) model, different strategies for causally regulating these free parameters are explored. The model can reproduce many of the observed features of TAI outflows but also exhibits physical attributes that empirical relationships alone miss. These characteristics include flux limiting of the outflow from below when intense outflow creates high-altitude cavities, time delays between the onset of transverse heating and the appearance of outflow, and spatial distributions of outflow which are different from the spatial distributions of the applied transverse heating and which depend on the ionospheric convection pattern.

  7. LOW-IONIZATION OUTFLOWS IN HIGH EDDINGTON RATIO QUASARS

    SciTech Connect

    Marzia