Sample records for high-energy cosmic rays

  1. High-energy Cosmic Rays

    E-print Network

    Thomas K. Gaisser; Todor Stanev

    2005-10-11

    After a brief review of galactic cosmic rays in the GeV to TeV energy range, we describe some current problems of interest for particles of very high energy. Particularly interesting are two features of the spectrum, the `knee' above $10^{15}$ eV and the `ankle' above $10^{18}$ eV. An important question is whether the highest energy particles are of extra-galactic origin and, if so, at what energy the transition occurs. A theme common to all energy ranges is use of nuclear abundances as a tool for understanding the origin of the cosmic radiation.

  2. High-energy cosmic ray interactions

    SciTech Connect

    Engel, Ralph [Forschungszentrum Karlsruhe, P.O. Box 3640, 76021 Karlsruhe (Germany); Orellana, Mariana [Instituto Argentino de Radioastronomia (IAR), CCT La Plata (CONICET), C.C.5, 1894 Villa Elisa, Buenos Aires (Argentina); Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque, 1900 La Plata (Argentina); Reynoso, Matias M. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350, (7600) Mar del Plata (Argentina); Instituto de Investigaciones Fisicas de Mar del Plata, (UNMdP-CONICET) (Argentina); Vila, Gabriela S. [Instituto Argentino de Radioastronomia (IAR), CCT La Plata (CONICET), C.C.5, 1894 Villa Elisa, Buenos Aires (Argentina)

    2009-04-30

    Research into hadronic interactions and high-energy cosmic rays are closely related. On one hand--due to the indirect observation of cosmic rays through air showers--the understanding of hadronic multiparticle production is needed for deriving the flux and composition of cosmic rays at high energy. On the other hand the highest energy particles from the universe allow us to study the characteristics of hadronic interactions at energies far beyond the reach of terrestrial accelerators. This is the summary of three introductory lectures on our current understanding of hadronic interactions of cosmic rays.

  3. Ultra High Energy Cosmic Rays

    E-print Network

    Miguel Mostafa

    2011-11-11

    Ultra high energy particles arrive at Earth constantly. They provide a beam at energies higher than any man-made accelerator, but at a very low rate. Two large experiments, the Pierre Auger Observatory and the Telescope Array experiment, have been taking data for several years now covering together the whole sky. I summarize the most recent measurements from both experiments, I compare their results and, for a change, I highlight their agreements.

  4. High-Energy Neutrinos from Cosmic Rays

    E-print Network

    F. Halzen

    2002-06-17

    We introduce neutrino astronomy from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back close to a century, we do not know how and where they are accelerated. We review the facts as well as the speculations about the sources. Among these gamma ray bursts and active galaxies represent well-motivated speculations because these are also the sources of the highest energy gamma rays, with emission observed up to 20 TeV, possibly higher. We discuss why cosmic accelerators are also expected to be cosmic beam dumps producing high-energy neutrino beams associated with the highest energy cosmic rays. Cosmic ray sources may produce neutrinos from MeV to EeV energy by a variety of mechanisms. The important conclusion is that, independently of the specific blueprint of the source, it takes a kilometer-scale neutrino observatory to detect the neutrino beam associated with the highest energy cosmic rays and gamma rays. The technology for commissioning such instruments exists.

  5. Significance of Ultra High Energy Cosmic Rays

    E-print Network

    Sidhu, Jasdeep

    2011-01-01

    The study of ultra high energy cosmic rays is a very important scientific problem. It is likely to have a huge impact in our understanding of the universe. Very high energy particles have been observed to hit the Earth whose origin is likely to be outside our Galaxy. Infact, particles with energies exceeding 10^ (20) electron volts which only hit the earth once in a century have been observed recently. The source of these high energy particles remains a deep and fascinating mystery yet to be resolved. Recently, a huge detector 30 times the size of the city of Paris is built by Pierre Auger Observatory to study these high energy particles. These detectors use the properties of Cherenkov radiation to identify the particles. Firstly, the paper will briefly explain the scientific motivation behind studying ultra high energy cosmic rays. Secondly, this paper will try to explain the reasons behind using water Cherenkov detectors. Thirdly, the paper within its limited scope, will try to give an overview of the exact...

  6. High Energy Cosmic Rays from Local GRBs

    E-print Network

    Atoyan, A

    2005-01-01

    We have developed a model that explains cosmic rays with energies E between \\~0.3 PeV and the energy of the second knee at E_2 ~ 3*10^{17} eV as originating from a recent Galactic gamma-ray burst (GRB) that occurred ~1 Myr ago within 1 kpc from Earth. Relativistic shocks from GRBs are assumed to inject power-law distributions of cosmic rays (CRs) to the highest energies. Diffusive propagation of CRs from the local GRB explains the CR spectrum near and above the first knee at E_1 ~ 3*10^{15} eV. The first and the second knees are explained as being directly connected with the injection of plasma turbulence in the interstellar medium on a ~1 pc and ~100 pc scales, respectively. Transition to CRs from extragalactic GRBs occurs at E > E_2. The origin of the ankle in the CR spectrum at E ~ 4*10^{18} eV is due to photopair energy losses of UHECRs on cosmological timescales, as also suggested by Berezinsky and collaborators. Any significant excess flux of extremely high energy CRs deviating from the exponential cuto...

  7. EDITORIAL: Focus on High Energy Cosmic Rays FOCUS ON HIGH ENERGY COSMIC RAYS

    NASA Astrophysics Data System (ADS)

    Teshima, Masahiro; Watson, Alan A.

    2009-06-01

    The topic of high-energy cosmic rays has recently attracted significant attention. While the AGASA and HiRes Observatories have closed after many years of successful operation, the Pierre Auger Observatory began taking data in January 2004 and the first results have been reported. Plans for the next generation of instruments are in hand: funding is now being sought for the northern phase of the Auger Observatory and plans for a space detector, JEM-EUSO, to be launched in 2013-14 are well advanced with the long-term target of a dedicated satellite for the 2020s. It therefore seemed an appropriate time to make a collection of outstanding and original research articles from the leading experimental groups and from some of the theorists who seek to interpret the hard-won data and to speculate on the origin of the highest energy cosmic rays. This focus issue in New Journal of Physics on the topic of high energy cosmic rays, contains a comprehensive account of the work of the Yakutsk group (A A Ivanov, S P Knurenko and I Ye Sleptsov) who have used Cerenkov radiation produced by shower particles in the air to provide the basis for energy calibration. This technique contrasts with that of detecting fluorescence radiation from space that is proposed for the JEM-EUSO instrument to be placed on the International Space Station in 2013, described by Y Takahashi. Supplementing this is an article by A Santangelo and A Petrolini describing the scientific goals, requirements and main instrument features of the Super Extreme Universe Space Observatory mission (S-EUSO). The use of fluorescence light to measure energies was the key component of the HiRes instrument and is also used extensively by the Pierre Auger Collaboration so an article, by F Arqueros, F Blanco and J Rosado, summarizing the properties of fluorescence emission, still not fully understood, is timely. M Nagano, one of the architects of the AGASA Observatory, has provided an overview of the experimental situation with regard to the energy spectrum of the highest energy cosmic rays. The remaining contributions are of a more theoretical nature and discuss propagation (T Stanev), the time structure of multi-messenger signals (G H W Sigl), ultra-high energy cosmic ray production near black holes (A Yu Neronov, D V Semikoz and I I Tkachev), production in jets associated with black holes (C D Dermer, S Razzaque, J Finke and A Atoyan) and emission from a specific object, Cen A (M Kachelriess, S S Ostapchenko and R Tomas). Additionally the potential of high energy cosmic rays to give information about features of hadronic interactions, specifically the cross-section for p-air collisions, is discussed in the paper by R Ulrich et al. We thank all our authors most sincerely for their efforts and Tim Smith and his editorial team for their hard work. We believe that this collection of articles will be of great value to workers in the field: further contributions to this focus issue will be published during the course of 2009. Focus on High Energy Cosmic Rays Contents The cosmic ray energy spectrum as measured using the Pierre Auger Observatory Giorgio Matthiae The northern site of the Pierre Auger Observatory Johannes Blümer and the Pierre Auger Collaboration Searching for new physics with ultrahigh energy cosmic rays Floyd W Stecker and Sean T Scully On the measurement of the proton-air cross section using air shower data R Ulrich, J Blümer, R Engel, F Schüssler and M Unger High energy radiation from Centaurus A M Kachelrieß, S Ostapchenko and R Tomàs Ultra-high-energy cosmic rays from black hole jets of radio galaxies C D Dermer, S Razzaque, J D Finke and A Atoyan Ultra-high energy cosmic ray production in the polar cap regions of black hole magnetospheres A Yu Neronov, D V Semikoz and I I Tkachev Time structure and multi-messenger signatures of ultra-high energy cosmic ray sources Günter Sigl Propagation of ultrahigh-energy cosmic rays Todor Stanev Search for the end of the energy spectrum of primary cosmic rays M Nagano Analysis of the fluorescence emission from atmospheric ni

  8. Terrestrial Effects of High Energy Cosmic Rays

    E-print Network

    Atri, Dimitra

    2011-04-26

    the radiation dose from cosmic rays causing damage to DNA and an increase in mutation rates and cancer, which can have serious biological implications for surface and sub-surface life. Using CORSIKA, we perform massive computer simulations and construct lookup...

  9. Detectors for high energy cosmic rays on Spacelab

    Microsoft Academic Search

    J. Lheureux; P. Meyer; D. Muller; S. Swordy

    1985-01-01

    Two instruments designed to determine the spectra of the individual cosmic-ray components at very high energies are described. One of these (CRNE) uses a combination of gas Cerenkov counters and transition radiation detectors for the cosmic-ray nuclei lithium to nickel; the other (TRIC) is optimized for the light cosmic rays (electrons, protons, helium) and uses a transition-radiation\\/ionization-calorimeter combination. The CRNE

  10. On the ultra-high energy cosmic ray horizon

    E-print Network

    D. Harari; S. Mollerach; E. Roulet

    2006-11-06

    We compute the ultra-high energy cosmic ray horizon, i.e. the distance up to which cosmic ray sources may significantly contribute to the fluxes above a certain threshold on the observed energies. We obtain results both for proton and heavy nuclei sources.

  11. Ultra High Energy Cosmic Rays: Observations and Theoretical Aspects

    E-print Network

    Daniel De Marco

    2006-09-05

    We present a brief introduction to the physics of Ultra High Energy Cosmic Rays (UHECRs), concentrating on the experimental results obtained so far and on what, from these results, can be inferred about the sources of UHECRs.

  12. Ultra-High Energy Cosmic Rays and Symmetries of Spacetime

    E-print Network

    O. Bertolami

    2001-05-15

    High energy cosmic rays allow probing phenomena that are inacessible to accelerators. Observation of cosmic rays, presumebly protons, with energies beyond $4 \\times 10^{19} eV$, the so-called Greisen-Zatsepin-Kuzmin (GZK) cut-off, give origin to two puzzles: How do particles accelerate to such energies ? Are their sources within $50 - 100 Mpc$ from Earth, or Lorentz invariance is actually a broken symmetry ?

  13. Ultra high energy neutrinos: the key to ultra high energy cosmic rays

    E-print Network

    Todor Stanev

    2006-07-26

    We discuss the relation between the acceleration spectra of extragalactic cosmic ray protons and the luminosity and cosmological evolution of their sources and the production of ultra high energy cosmogenic neutrinos in their propagation from the sources to us.

  14. High Energy Cosmic Electrons: Messengers from Nearby Cosmic Ray Sources or Dark Matter?

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander

    2011-01-01

    This slide presentation reviews the recent discoveries by the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-Ray Telescope in reference to high energy cosmic electrons, and whether their source is cosmic rays or dark matter. Specific interest is devoted to Cosmic Ray electrons anisotropy,

  15. Acceleration and Interaction of Ultra High Energy Cosmic Rays

    E-print Network

    R. J. Protheroe

    1998-12-03

    In this chapter I give an overview of shock acceleration, including a discussion of the maximum energies possible and the shape of the spectrum near cut-off, interactions of high energy cosmic rays with, and propagation through, the background radiation, and the resulting electron-photon cascade. Possible sources of the highest energy cosmic rays are discussed including active galaxies, gamma ray bursts and topological defects. I argue that while the origin of the highest energy cosmic rays is still uncertain, it is not necessary to invoke exotic models such as emission by topological defects to explain the existing data. It seems likely that shock acceleration at Fanaroff-Riley Class II radio galaxies can account for the existing data. However, new cosmic ray data, as well as better estimates of the extragalactic radiation fields and magnetic fields will be necessary before we will be certain of the origin of the highest energy particles occurring in nature.

  16. Experimental Ultra--High-Energy Cosmic Ray Physics

    E-print Network

    Stefan Westerhoff

    2005-12-07

    One of the most striking astrophysical phenomena today is the existence of cosmic ray particles with energies in excess of 10^20 eV. While their presence has been confirmed by a number of experiments, it is not clear where and how these particles are accelerated to these energies and how they travel astronomical distances without substantial energy loss. We are entering an exciting new era in cosmic ray physics, with instruments now producing data of unprecedented quality and quantity to tackle the many open questions. This paper reviews the current experimental status of cosmic ray physics and summarizes recent results on the energy spectrum and arrival directions of ultra-high-energy cosmic rays.

  17. Ultra High-Energy Cosmic Rays from Quasar Remnants

    Microsoft Academic Search

    Timothy Hamilton; Elihu Boldt; Michael Loewenstein

    2004-01-01

    The sources of Ultra High-Energy Cosmic Rays (UHECR) are still mysterious, but those at the highest energies may be accelerated in a compact dynamo, such as a quasar remnant. Such a dynamo is composed of a supermassive black hole with a substantial, accretion-supported magnetic field, an especially dark radiation environment, and near maximal spin. This kind of compact dynamo at

  18. Search for ultra high energy cosmic ray anisotropy with Auger

    Microsoft Academic Search

    Pedram Boghrat

    2008-01-01

    Although the existence of ultra high energy cosmic rays (UHECR) with energies on the order of 10 20 eV, has been shown by past experiments, the source of these particles is not yet understood. Theoretical models motivate the consideration of nearby active galactic nuclei (AGN) as a source candidate. However, AGN have not been declared as the source unambiguously and

  19. Ultra High Energy Comic Rays in the Cosmic Microwave Background

    E-print Network

    W-Y. Pauchy Hwang; Bo-Qiang Ma

    2011-07-22

    We consider the propagation of ultra high energy cosmic rays (UHECR), for energies greater than E > 10^{14} eV but less than E < 10^{26} eV, in the cosmic medium of the Cosmic Microwave Background (CMB). We find that the CMB plays a pivot role in this energy range. As example, the observed "knee(s)" and the "ankle" could be understood in reasonable terms. What we may observe at energy near 10^{25} eV (W^\\pm bursts or Z^0 bursts) is also briefly discussed.

  20. Ultra High Energy Comic Rays in the Cosmic Microwave Background

    E-print Network

    Hwang, W-Y Pauchy

    2011-01-01

    We consider the propagation of ultra high energy cosmic rays (UHECR), for energies greater than E > 10^{14} eV but less than E < 10^{26} eV, in the cosmic medium of the Cosmic Microwave Background (CMB). We find that the CMB plays a pivot role in this energy range. As example, the observed "knee(s)" and the "ankle" could be understood in reasonable terms. What we may observe at energy near 10^{25} eV (W^\\pm bursts or Z^0 bursts) is also briefly discussed.

  1. Cosmic strings and ultra-high energy cosmic rays

    NASA Technical Reports Server (NTRS)

    Bhattacharjee, Pijushpani

    1989-01-01

    The flux is calculated of ultrahigh energy protons due to the process of cusp evaporation from cosmic string loops. For the standard value of the dimensionless cosmic string parameter epsilon is identical to G(sub mu) approx. = 10(exp -6), the flux is several orders of magnitude below the observed cosmic ray flux of ultrahigh energy protons. However, the flux at any energy initially increases as the value of epsilon is decreased. This at first suggests that there may be a lower limit on the value of epsilon, which would imply a lower limit on the temperature of a cosmic string forming phase transition in the early universe. However, the calculation shows that this is not the case -- the particle flux at any energy reaches its highest value at epsilon approx. = 10(exp -15) and it then decreases for further decrease of the value of epsilon. This is due to the fact that for too small values of epsilon (less than 10(exp -15)), the energy loss of the loops through the cusp evaporation process itself (rather than gravitational energy loss of the loops) becomes the dominant factor that controls the behavior of the number density of the loops at the relevant times of emission of the particles. The highest flux at any energy remains at least four orders of magnitude below the observed flux. There is thus no lower limit on epsilon.

  2. Ultra High Energy Cosmic Rays Diffusion in an Expanding Universe

    E-print Network

    R. Aloisio; V. Berezinsky; A. Gazizov

    2007-06-14

    We study the solution of the diffusion equation for Ultra-High Energy Cosmic Rays in the general case of an expanding universe, comparing it with the well known Syrovatsky solution obtained in the more restrictive case of a static universe. The formal comparison of the two solutions with all parameters being fixed identically reveals an appreciable discrepancy. This discrepancy is less important if in both models a different set of best-fit parameters is used.

  3. pp interaction at very high energies in cosmic ray experiments

    NASA Astrophysics Data System (ADS)

    Kendi Kohara, A.; Ferreira, Erasmo; Kodama, Takeshi

    2014-11-01

    An analysis of p-air cross section data from extensive air shower measurements is presented, based on an analytical representation of the pp scattering amplitudes that describes with high precision all available accelerator data at ISR, SPS and LHC energies. The theoretical basis of the representation, together with the very smooth energy dependence of parameters controlled by unitarity and dispersion relations, permits reliable extrapolation to high energy cosmic ray (CR) and asymptotic energy ranges. Calculations of ? p-airprod based on Glauber formalism are made using the input values of the quantities ? , ? , BI and BR at high energies, with attention given to the independence of the slope parameters, with {{B}R}\

  4. On the Origin of Ultra High Energy Cosmic Rays

    SciTech Connect

    Fowler, T; Colgate, S; Li, H

    2009-07-01

    Turbulence-driven plasma accelerators produced by magnetized accretion disks around black holes are proposed as the mechanism mainly responsible for observed cosmic ray protons with ultra high energies 10{sup 19}-10{sup 21} eV. The magnetized disk produces a voltage comparable to these cosmic ray energies. Here we present a Poynting model in which this voltage provides all of the energy to create the jet-like structures observed to be ejected from accretion disks, and this voltage also accelerates ions to high energies at the top of the expanding structure. Since the inductive electric field E = -v x B driving expansion has no component parallel to the magnetic field B, ion acceleration requires plasma wave generation - either a coherent wave accelerator as recently proposed, or instability-driven turbulence. We find that turbulence can tap the full inductive voltage as a quasi-steady accelerator, and even higher energies are produced by transient events on this structure. We find that both MHD modes due to the current and ion diffusion due to kinetic instability caused by the non-Maxwellian ion distribution contribute to acceleration. We apply our results to extragalactic giant radiolobes, whose synchrotron emissions serve to calibrate the model, and we discuss extrapolating to other astrophysical structures. Approximate calculations of the cosmic ray intensity and energy spectrum are in rough agreement with data and serve to motivate more extensive MHD and kinetic simulations of turbulence that could provide more accurate cosmic ray and synchrotron spectra to be compared with observations. A distinctive difference from previous models is that the cosmic ray and synchrotron emissions arise from different parts of the magnetic structure, thus providing a signature for the model.

  5. Ultra High Energy Cosmic Rays from Decaying Superheavy Particles

    E-print Network

    V. Berezinsky

    1998-01-08

    Decaying superheavy particles can be produced by Topological Defects or, in case they are quasi-stable, as relics from the early Universe. The decays of these particles can be the sources of observed Ultra High Energy Cosmic Rays ($E \\sim 10^{10} - 10^{12} GeV$). The Topological Defects as the UHE CR sources are critically reviewed and cosmic necklaces and monopole-antiminopole pairs are identified as most plausible sources. The relic superheavy particles are shown to be clustering in the halo and their decays produce UHE CR without GZK cutoff. The Lightest Supersymmetric Particles with Ultra High Energies are naturally produced in the cascades accompanying the decays of superheavy particles. These particles are discussed as UHE carriers in the Universe.

  6. Search for very high energy gamma rays from possible ultra-high energy cosmic ray sources by the MAGIC Telescope

    E-print Network

    K. Shinozaki; M. Teshima; for the MAGIC Collaboration

    2007-09-17

    The origin of ultra-high energy (UHE) cosmic rays is still an open question. In the present work, we searched the possible UHE cosmic ray sources using the MAGIC telescope for the associated very high energy (VHE) gamma ray emission. Due to constrained propagation distance of such cosmic rays, we selected nearby galaxies in vicinity of the direction of the AGASA triplet and a HiRes UHE cosmic ray event: NGC 3610 and NGC 3613 (quasar remnants); Arp 299 (a system of colliding galaxies). No significant excess in the VHE region was found found from these objects or their surrounding region. At multi-100 GeV regime, the upper limits on fluxes were given against gamma ray sources in surrounding region. The presented limits constrain the flux of a new hypothetical source in the region, provided the cosmic rays are emitted from a single point-like origin.

  7. The composition of cosmic rays at high energies

    NASA Technical Reports Server (NTRS)

    Muller, Dietrich

    1989-01-01

    Measurements of the composition of the cosmic rays at high energies, and of the energy spectra of the individual components provide the basis for the understanding of the sources, of the acceleration mechanism, and of the galactic containment of these particles. A brief review of the presently available information and a recent measurement performed on the Space Shuttle to substantially extend the range of energies in which the elemental composition is known are described. Results, and recent data on the electron component of cosmic rays are discussed and summarized. The body of data now available contains several features that are difficult to explain within current models of galactic shock acceleration and 'leakly box' containment. The need for further measurements is emphasized and possible opportunities for future work are briefly discussed.

  8. Cosmic Ray Positrons at High Energies: A New Measurement

    E-print Network

    HEAT Collaboration

    1995-05-30

    We present a new measurement of the cosmic-ray positron fraction e+/(e+ + e-) obtained from the first balloon flight of the High Energy Antimatter Telescope (HEAT). Using a magnet spectrometer combined with a transition radiation detector, an electromagnetic calorimeter, and time-of-flight counters we have achieved a high degree of background rejection. Our results do not indicate a major contribution to the positron flux from primary sources. In particular, we see no evidence for the significant rise in the positron fraction at energies above ~10 GeV previously reported.

  9. Searching for new phenomena in high energy cosmic rays

    NASA Astrophysics Data System (ADS)

    Cholis, Ilias

    2010-12-01

    The focus of my work has been attempting to study how cosmic rays may help us understand the nature of dark matter. This question is at the intersection of particle physics and astrophysics, and involves questions of particle physics model building, production and propagation of cosmic rays, and connections to collider physics. My interest has been the properties of various DM candidates that would annihilate into Standard Model particles producing eventually high energy e+ and e - as well as p and p¯ that could influence their locally measured ratios at high energies. I have focused on models that produce significant amounts of hard positrons, and have considered the propagation of the resulting cosmic rays in the galaxy, namely electrons positrons and antiprotons as well as some heavier nuclei. Among the experiments whose data I have studied are HEAT, PAMELA, ATIC and Fermi. An other interesting aspect has been the possible explanation of the "microwave WMAP Haze" that Finkbeiner has calculated from CMB data at the central part of the galaxy, and its inverse Compton scattering counterpart the Fermi gamma-ray haze. The connection to synchrotron radiation and inverse Compton scattering from high energy e- and e+ of annihilating DM origin has also been part of my work. Moreover the connection of those results to the results from PAMELA and ATIC/Fermi within the same DM framework has been one of the goals of my studies. As an alternative to DM, Pulsars could be used to explain the recent results from the PAMELA Collaboration. As Pulsars spin down their energy high numbers of electron and positron pairs are produced via pair creation from X-rays emitted by high energy electrons at the poles of the Pulsars. The implications of the resulting injected into the ISM e+/- to the local spectra has also been part of my work. Also the significance of millisecond pulsars in the bulge and their implications to both the microwave and the gamma-ray Haze, in combination with existing DM models has been part of my research work.

  10. GZK Photons as Ultra High Energy Cosmic Rays

    E-print Network

    Graciela B. Gelmini; Oleg E. Kalashev; Dmitry V. Semikoz

    2007-11-01

    We calculate the flux of "GZK-photons", namely the flux of Ultra High Energy Cosmic Rays (UHECR) consisting of photons produced by extragalactic nucleons through the resonant photoproduction of pions, the so called GZK effect. We We calculate the flux of "GZK-photons", namely the flux of Ultra High Energy Cosmic Rays (UHECR) consisting of photons produced by extragalactic nucleons through the resonant photoproduction of pions, the so called GZK effect. We show that, for primary nucleons, the GZK photon fraction of the total UHECR flux is between $10^{-4}$ and $10^{-2}$ above $10^{19}$ eV and up to the order of 0.1 above $10^{20}$ eV. The GZK photon flux depends on the assumed UHECR spectrum, slope of the nucleon flux at the source, distribution of sources and intervening backgrounds. Detection of this photon flux would open the way for UHECR gamma-ray astronomy. Detection of a larger photon flux would imply the emission of photons at the source or new physics. We compare the photon fractions expected for GZK photons and the minimal predicted by Top-Down models. We find that the photon fraction above $10^{19}$ eV is a crucial test for Top-Down models.

  11. Ultra high energy cosmic rays from cosmological relics

    E-print Network

    V. Berezinsky

    1998-11-17

    Ultra High Energy Cosmic Rays (UHECR) can be a signal from very early (post-inflationary) Universe. At this cosmological epoch Topological Defects (TD) and long-lived suprheavy (SH) particles are expected to be naturally and effectively produced. Both of these relics can produce now the particles, such as protons and photons, with energies in a great excess of what is observed in UHECR, $E \\sim 10^{10} - 10^{11} GeV$. The Topological Defects as the UHECR sources are critically reviewed and cosmic necklaces and monopolonia are identified as most plausible sources. The relic superheavy particles and monopolonia are shown to be clustering in the halo of our Galaxy and their decays produce UHECR without the GZK cutoff. The observational signature of both models are discussed.

  12. Origin and Propagation of Ultra-High Energy Cosmic Rays

    E-print Network

    Gustavo A. Medina Tanco; Elisabete M. de Gouveia Dal Pino; Jorge E. Horvatth

    1999-01-06

    The existence of cosmic ray particles up to the ultra-high energy limit (> 10^20 eV) is now beyond any doubt. The detection of cosmic particles with such energies imposes a challenge for the comprehension of their sources and nature. On one side, particles with such high energies are difficult to be produced by any astrophysical source. On the other side, the interactions of these particles with photons of the cosmic microwave background cause substantial losses of energy which constraint the maximum distances that the particles are able to travel from the sources to the detectors. Aiming to help to elucidate the problem of UHECR source identification, we have performed 3-D simulations of particle trajectories propagated through the stochastic intergalactic and an extended Galactic halo magnetic fields. Going further, we have also performed simulations of proton and Fe nuclei through the spiral Galactic magnetic field (GMF) and built full-sky maps of their arrival direction distribution in both the detector (after deflection in the GMF) and just outside the Galaxy. In this work we summarize the main results of these investigations.

  13. Gamma-ray bursts: Potential sources of ultra high energy cosmic-rays

    E-print Network

    E. Waxman

    2004-12-21

    The arguments suggesting an association between the sources of cosmological gamma-ray bursts (GRBs) and the sources of ultra-high energy cosmic rays (UHECRs) are presented. Recent GRB and UHECR observations are shown to strengthen these arguments. Predictions of the GRB model for UHECR production, that may be tested with large area high energy cosmic-ray detectors which are either operating or under construction, are outlined.

  14. ENERGY SPECTRA OF COSMIC-RAY NUCLEI AT HIGH ENERGIES

    SciTech Connect

    Ahn, H. S.; Ganel, O.; Han, J. H.; Kim, K. C.; Lee, M. H.; Malinine, A. [Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742 (United States); Allison, P.; Beatty, J. J.; Brandt, T. J. [Department of Physics, Ohio State University, Columbus, OH 43210 (United States); Bagliesi, M. G.; Bigongiari, G.; Maestro, P.; Marrocchesi, P. S. [Department of Physics, University of Siena and INFN, Via Roma 56, 53100 Siena (Italy); Barbier, L. [Astroparticle Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Childers, J. T.; DuVernois, M. A. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Conklin, N. B.; Coutu, S. [Department of Physics, Penn State University, University Park, PA 16802 (United States); Jeon, J. A. [Department of Physics, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Minnick, S., E-mail: paolo.maestro@pi.infn.i [Department of Physics, Kent State University, Tuscarawas, New Philadelphia, OH 44663 (United States)

    2009-12-10

    We present new measurements of the energy spectra of cosmic-ray (CR) nuclei from the second flight of the balloon-borne experiment Cosmic-Ray Energetics And Mass (CREAM). The instrument included different particle detectors to provide redundant charge identification and measure the energy of CRs up to several hundred TeV. The measured individual energy spectra of C, O, Ne, Mg, Si, and Fe are presented up to approx10{sup 14} eV. The spectral shape looks nearly the same for these primary elements and it can be fitted to an E {sup -2.66} {sup +}- {sup 0.04} power law in energy. Moreover, a new measurement of the absolute intensity of nitrogen in the 100-800 GeV/n energy range with smaller errors than previous observations, clearly indicates a hardening of the spectrum at high energy. The relative abundance of N/O at the top of the atmosphere is measured to be 0.080 +- 0.025 (stat.)+-0.025 (sys.) at approx800 GeV/n, in good agreement with a recent result from the first CREAM flight.

  15. Deformed Lorentz Symmetry and Ultra-High Energy Cosmic Rays

    E-print Network

    Luis Gonzalez-Mestres

    1999-05-24

    Lorentz symmetry violation (LSV) is often discussed using models of the $TH\\epsilon \\mu $ type which involve, basically, energy independent parameters. However, if LSV is generated at the Planck scale or at some other fundamental length scale, it can naturally preserve Lorentz symmetry as a low-energy limit (deformed Lorentz symmetry, DLS). Deformed relativistic kinematics (DRK) would be consistent with special relativity in the limit $k$ (wave vector) $\\to ~0$ and allow for a deformed version of general relativity and gravitation. We present an updated discussion of the possible implications of this pattern for cosmic-ray physics at very high energy. A $\\approx ~10^{-6}$ LSV at Planck scale, leading to a DLS pattern, would potentially be enough to produce very important observable effects on the properties of cosmic rays at the $\\approx \\~10^{20} eV$ scale (absence of GZK cutoff, stability of unstable particles, lower interaction rates, kinematical failure of the parton model...). We compare our approach with more recent similar claims made by S. Coleman and S. Glashow from models of the $TH\\epsilon \\mu$ type.

  16. Ultra-high energy cosmic rays from decaying relic particles.

    NASA Astrophysics Data System (ADS)

    Berezinsky, V.; Kachelriess, M.; Vilenkin, A.

    1999-01-01

    The authors report on a recent proposal that particles produced by the decays of ultraheavy and quasistable X-particles constitute the ultra high energy cosmic rays (UHECR). These X-particles are assumed to constitute a tiny fraction ?x of cold dark matter in the Universe, with ?x being the same in the halo of our Galaxy and in the intergalactic space. The UHECR fluxes produced at the decays of X-particles are dominated by photons and nucleons from the halo of our Galaxy. Thus they do not exihibit the Greisen-Zatsepin-Kuz'min cutoff and the cascade limit is relaxed. The authors discuss the spectrum of produced extensive air showers and a signal from the Virgo cluster as signatures of this model.

  17. RADAR SENSING OF ULTRA-HIGH ENERGY COSMIC RAY SHOWERS

    E-print Network

    overview of a currently planned radar experiment at the Telescope Array. There is much activity in cosmic-VHF with a large obstruction between receiver and transmitter (such as a mountain or earth curvature), which][6][7] Figure 1.2: Diagram of EAS shower and ionization column[8] Cosmic rays of this energy are extremely rare

  18. The high energy cosmic ray detector for Spacelab II

    Microsoft Academic Search

    J. E. Lamport; J. Lheureux; P. Meyer; D. Muller

    1980-01-01

    A large cosmic ray detector to be flown on Spacelab II is presently under construction at the University of Chicago. The instrument, with a geometric factor of 5 sq m-ster, is designed to measure the elemental composition and the energy spectra of individual cosmic ray nuclei (Li to Fe) from 50 GeV\\/nucleon to several TeV\\/nucleon. Plastic scintillators are used for

  19. Energy spectrum of ultra high energy cosmic rays

    E-print Network

    Ioana C. Maris; for the Pierre Auger Collaboration

    2008-08-12

    The construction of the southern site of the Pierre Auger Observatory is almost completed. Three independent measurements of the flux of the cosmic rays with energies larger than 1 EeV have been performed during the construction phase. The surface detector data collected until August 2007 have been used to establish a flux suppression at the highest energies with a 6 sigma significance. The observations of cosmic rays by the fluorescence detector allowed the extension of the energy spectrum to lower energies, where the efficiency of the surface detector is less than 100% and a change in the spectral index is expected.

  20. The Compton–Getting effect on ultra-high energy cosmic rays of cosmological origin

    Microsoft Academic Search

    M. Kachelrieß; P. D. Serpico

    2006-01-01

    Deviations from isotropy have been a key tool to identify the origin and the primary type of cosmic rays at low energies. We suggest that the Compton–Getting effect can play a similar role at ultra-high energies: If at these energies the cosmic ray flux is dominated by sources at cosmological distances, then the movement of the Sun relative to the

  1. The development of a high energy cosmic ray detector for Spacelab2

    Microsoft Academic Search

    J. Lheureux; P. Meyer; D. Mueller; S. P. Swordy

    1985-01-01

    A large cosmic ray detector aimed at measurements of the energy spectra and of the elemental abundances of cosmic ray nuclei at very high energies, up to several TeV\\/nucleon was constructed. The instrument is an electronic counter telescope with a geometric factor of 5 sq ster. It accomplishes measurements of the particle energies through the use of gas Cerenkov counters

  2. The Fly's Eye Extremely High Energy Cosmic Ray Spectrum D.J. Bird,1

    E-print Network

    The Fly's Eye Extremely High Energy Cosmic Ray Spectrum D.J. Bird,1 S.C. Corbato,3 H.Y. Dai,3 B present our latest results on the cosmic ray energy spectrum above 1017 eV observed by Fly's Eye. Tracks detected by both eyes can be well reconstructed and therefore have very good energy resolution

  3. The size of antimatter bodies and the primary very high energy cosmic ray flux

    Microsoft Academic Search

    J. R. Wayland

    1970-01-01

    The consequences of antimatter bodies on the very high energy primary cosmic ray flux are considered. The effects of various models of cosmic ray origin and properties of astrophysical parameters are discussed. A simple expression for the production of antiprotons inN-N collisions as a function of energy of the incident proton is obtained by utilizing characteristics of particles produced in

  4. The Size of Antimatter Bodies and the Primary Very High Energy Cosmic Ray Flux

    Microsoft Academic Search

    J. R. Wayland

    1970-01-01

    The consequences of antimatter bodies on the very high energy primary cosmic ray flux are considered. The effects of various models of cosmic ray origin and properties of astrophysical parameters are discussed. A simple expression for the production of antiprotons inN-N collisions as a function of energy of the incident proton is obtained by utilizing characteristics of particles produced in

  5. Electron calibration of a high energy cosmic ray detector

    NASA Technical Reports Server (NTRS)

    Simnett, G. M.; Silverberg, R. F.; Crannell, C. J.; Gearhart, R. A.; Hagen, F. A.; Jones, W. V.; Kurz, R. J.; Ormes, J. F.; Price, R. D.

    1972-01-01

    The spectrum of cosmic ray electrons above 10 GeV was studied extensively. The spectrum is predicted to steepen at an energy which is related to the lifetime of electrons in the interstellar medium against losses due to inverse Compton collisions with photons and to synchrotron radiation in galactic magnetic fields. The experimental results diverge widely; the lack of agreement between the various measurements is due to a variety of experimental problems.

  6. Analytic Solutions of Ultra-High Energy Cosmic Ray Nuclei Revisited

    E-print Network

    Markus Ahlers; Andrew M. Taylor

    2010-10-14

    The chemical composition of ultra-high energy cosmic rays is a key question in particle astrophysics. The measured composition, inferred from the elongation rates of cosmic ray showers, looks in general very different from the initial source composition: resonant photo-disintegration in the cosmic radiation background proceeds rapidly at the highest energies and the initial composition quickly becomes lighter during propagation. For a statistical analysis of continuously improving cosmic ray data it is desirable to know the secondary spectra as precisely as possible. Here, we discuss exact analytic solutions of the evolution equation of ultra-high energy cosmic ray nuclei. We introduce a diagrammatic formalism that leads to a systematic analytic expansion of the exact solution in terms of second order effects of the propagation. We show how the first order corrections of this expansion can improve the predictions of secondary spectra in a semi-analytical treatment.

  7. Searching for Extra Dimensions in High Energy Cosmic Rays

    E-print Network

    Alessandro Cafarella; Claudio Coriano'; T. N. Tomaras

    2004-10-27

    We present a study of the decay of an intermediate mini black hole at the first impact of a cosmic ray particle with the atmosphere, in the context of D-brane world scenarios with TeV scale gravity and large extra dimensions. We model the decay of the black hole using the semiclassical approximation and include the corrections coming from energy loss into the bulk. Extensive simulations show that mini black hole events are characterized by essentially different multiplicities and wider lateral distributions of the air showers as a function of the energy of the incoming primary, as compared to standard events. Implications for their detection and some open issues on their possible discovery are also briefly addressed.

  8. Contribution from individual nearby sources to the spectrum of high-energy cosmic-ray electrons

    NASA Astrophysics Data System (ADS)

    Sedrati, R.; Attallah, R.

    2014-04-01

    In the last few years, very important data on high-energy cosmic-ray electrons and positrons from high-precision space-born and ground-based experiments have attracted a great deal of interest. These particles represent a unique probe for studying local comic-ray accelerators because they lose energy very rapidly. These energy losses reduce the lifetime so drastically that high-energy cosmic-ray electrons can attain the Earth only from rather local astrophysical sources. This work aims at calculating, by means of Monte Carlo simulation, the contribution from some known nearby astrophysical sources to the cosmic-ray electron/positron spectra at high energy (?10 GeV). The background to the electron energy spectrum from distant sources is determined with the help of the GALPROP code. The obtained numerical results are compared with a set of experimental data.

  9. Ultra-High Energy Cosmic Rays, Spiral galaxies and Magnetars

    E-print Network

    G. Ghisellini; G. Ghirlanda; F. Tavecchio; F. Fraternali; G. Pareschi

    2008-08-17

    We measure the correlation between the arrival directions of the highest energy cosmic rays detected by the Pierre Auger Observatory with the position of the galaxies in the HI Parkes All Sky Survey (HIPASS) catalogue, weighted for their HI flux and Auger exposure. The use of this absorption-free catalogue, complete also along the galactic plane, allows us to use all the Auger events. The correlation is significant, being 86.2% for the entire sample of HI galaxies, and becoming 99% when considering the richest galaxies in HI content, or 98% with those lying between 40-55. We interpret this result as the evidence that spiral galaxies are the hosts of the producers of UHECR and we briefly discuss classical (i.e energetic and distant) long Gamma Ray Burst (GRBs), short GRBs, as well as newly born or late flaring magnetars as possible sources of the Auger events. With the caveat that these events are still very few, and that the theoretical uncertainties are conspicuous, we found that newly born magnetars are the best candidates. If so, they could also be associated with sub-energetic, spectrally soft, nearby, long GRBs. We finally discuss why there is a clustering of Auger events in the direction on the radio-galaxy Cen A and an absence of events in the direction of the radio-galaxy M87.

  10. TUNKA-133: A new array for the study of ultra-high energy cosmic rays

    Microsoft Academic Search

    B. V. Antokhonov; S. F. Berezhnev; D. Besson; N. M. Budnev; R. Wischnevski; O. A. Gress; A. N. Diachok; A. V. Zablotsky; A. V. Zagorodnikov; N. N. Kalmykov; N. I. Karpov; V. A. Kozhin; E. E. Korosteleva; A. V. Korobchenko; L. A. Kuzmichev; A. Chiavassa; B. K. Lubsandorzhiev; R. R. Mirgazov; M. I. Panasyuk; L. V. Pankov; V. V. Prosin; V. S. Ptuskin; Yu. A. Semeney; A. A. Silaev; A. V. Skurikhin; M. Stokham; O. A. Chvalaiev; B. A. Shaibonov; J. Snyder; Ch. Spiering; I. V. Yashin

    2011-01-01

    A new array for studying ultra-high energy cosmic rays was inaugurated in 2009 in the Tunka Valley, about 50 km from Lake\\u000a Baikal. Having an area of 1 km2, the new facility allows us to study cosmic rays with energies of 1015–1018 eV via the a unified method for registering Cherenkov radiation from extensive air showers (EASes) and is making

  11. High-energy cosmic ray muons in the Earth's atmosphere

    SciTech Connect

    Kochanov, A. A., E-mail: kochanov@iszf.irk.ru [Russian Academy of Sciences, Siberian Branch, Institute of Solar-Terrestrial Physics (Russian Federation); Sinegovskaya, T. S. [Irkutsk State Railway University (Russian Federation)] [Irkutsk State Railway University (Russian Federation); Sinegovsky, S. I., E-mail: sinegovsky@api.isu.ru [Irkutsk State University (Russian Federation)

    2013-03-15

    We present the calculations of the atmospheric muon fluxes at energies 10-10{sup 7} GeV based on a numerical-analytical method for solving the hadron-nucleus cascade equations. It allows the non-power-law behavior of the primary cosmic ray (PCR) spectrum, the violation of Feynman scaling, and the growth of the total inelastic cross sections for hadron-nucleus collisions with increasing energy to be taken into account. The calculations have been performed for a wide class of hadron-nucleus interaction models using directly the PCR measurements made in the ATIC-2 and GAMMA experiments and the parameterizations of the primary spectrum based on a set of experiments. We study the dependence of atmospheric muon flux characteristics on the hadronic interaction model and the influence of uncertainties in the PCR spectrum and composition on the muon flux at sea level. Comparison of the calculated muon energy spectra at sea level with the data from a large number of experiments shows that the cross sections for hadron-nucleus interactions introduce the greatest uncertainty in the energy region that does not include the knee in the primary spectrum.

  12. 18. Supernova remnants and the origin of cosmic rays 18.1 High-energy emission from SNR

    E-print Network

    Pohl, Martin Karl Wilhelm

    18. Supernova remnants and the origin of cosmic rays 18.1 High-energy emission from SNR We have already mentioned supernova remnants as possible sources of cosmic rays, and indeed synchrotron emission rays, then the cosmic-ray density in and near the SNR should be very high, so one should be able to see

  13. Lookup tables to compute high energy cosmic ray induced atmospheric ionization and changes in atmospheric chemistry

    SciTech Connect

    Atri, Dimitra; Melott, Adrian L. [Department of Physics and Astronomy, University of Kansas, 1251 Wescoe Dr. 1082, Lawrence, KS 66045-7582 (United States); Thomas, Brian C., E-mail: dimitra@ku.edu, E-mail: melott@ku.edu, E-mail: brian.thomas@washburn.edu [Department of Physics and Astronomy, Washburn University, 1700 SW College Ave., Topeka, KS 66621 (United States)

    2010-05-01

    A variety of events such as gamma-ray bursts and supernovae may expose the Earth to an increased flux of high-energy cosmic rays, with potentially important effects on the biosphere. Existing atmospheric chemistry software does not have the capability of incorporating the effects of substantial cosmic ray flux above 10 GeV. An atmospheric code, the NASA-Goddard Space Flight Center two-dimensional (latitude, altitude) time-dependent atmospheric model (NGSFC), is used to study atmospheric chemistry changes. Using CORSIKA, we have created tables that can be used to compute high energy cosmic ray (10 GeV–1 PeV) induced atmospheric ionization and also, with the use of the NGSFC code, can be used to simulate the resulting atmospheric chemistry changes. We discuss the tables, their uses, weaknesses, and strengths.

  14. Constraining sources of ultra high energy cosmic rays using high energy observations with the Fermi satellite

    SciTech Connect

    Pe'er, Asaf; Loeb, Abraham, E-mail: apeer@cfa.harvard.edu, E-mail: aloeb@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, MS-51, 60 Garden Street, Cambridge, MA 02138 (United States)

    2012-03-01

    We analyze the conditions that enable acceleration of particles to ultra-high energies, ? 10{sup 20} eV (UHECRs). We show that broad band photon data recently provided by WMAP, ISOCAM, Swift and Fermi satellites, yield constraints on the ability of active galactic nuclei (AGN) to produce UHECRs. The high energy (MeV–GeV) photons are produced by Compton scattering of the emitted low energy photons and the cosmic microwave background or extra-galactic background light. The ratio of the luminosities at high and low photon energies can therefore be used as a probe of the physical conditions in the acceleration site. We find that existing data excludes core regions of nearby radio-loud AGN as possible acceleration sites of UHECR protons. However, we show that giant radio lobes are not excluded. We apply our method to Cen A, and show that acceleration of protons to ? 10{sup 20} eV can only occur at distances ?>100 kpc from the core.

  15. The Most Likely Sources of High-Energy Cosmic-Ray Electrons in Supernova Remnants

    Microsoft Academic Search

    T. Kobayashi; Y. Komori; K. Yoshida; J. Nishimura

    2004-01-01

    Evidence of nonthermal X-ray emission and TeV gamma rays from supernova remnants (SNRs) have strengthened the hypothesis that primary Galactic cosmic-ray electrons are accelerated in SNRs. High-energy electrons lose energy via synchrotron and inverse Compton processes during propagation in the Galaxy. Because of these radiative losses, TeV electrons liberated from SNRs at distances larger than ~1 kpc, or times older

  16. Ultra-high energy cosmic rays and the extragalactic gamma ray flux

    E-print Network

    Erlykin, A D

    2014-01-01

    Ultra-high energy cosmic rays interacting with the radiation fields in the universe cause electromagnetic cascades resulting in a flux of extragalactic gamma rays, detectable to some 100 GeV. Recent precise measurements of the extragalactic gamma ray flux by Fermi-LAT, coupled with estimates of the background from active galactic nuclei of various types, allows limits to be set on the cascade component. By comparison with prediction and, making various assumptions, ie taking a particular model, limits can be set on the maximum energy to which ultra-high energy particle can be accelerated. If our model is correct, it is unlikely that the maximum energy is above 100 EeV, in turn, the apparent 'GZK' cut-off in the measured ultra-high energy spectrum could instead be due to a fall-off in the intrinsic emergent particle spectrum. However, it is not plausible to be dogmatic at the present time because of uncertainty in many of the parameters involved. We have used recent estimates of the range of parameters and hav...

  17. Shock Acceleration of High-Energy Cosmic Rays: The Importance of the Magnetic-Field Angle

    E-print Network

    Shock Acceleration of High-Energy Cosmic Rays: The Importance of the Magnetic-Field Angle Joe-mail: giacalon@lpl.arizona.edu Abstract. The physics of particle acceleration by collisionless shocks of the angle between the shock normal and upstream mean magnetic field, Bn , in determining the energy spectrum

  18. Isotropization of ultra-high energy cosmic ray arrival directions by radio ghosts

    Microsoft Academic Search

    Gustavo Medina-Tanco; Torsten A. Enßlin

    2001-01-01

    The isotropy in the ultra-high energy cosmic ray (UHECR) flux observed by Yakutsk and AGASA experiments, is a very strong constraint to production and propagation models alike. Most of the scenarios proposed in the literature should produce a sizable anisotropy as either extragalactic luminous or dark matter is normally associated with the invoked particle sources. We explore the possibility that

  19. Relations Between High Energy Astroparticle Physics, Cosmic Ray Physics and Space Situational Awareness

    Microsoft Academic Search

    Frank Jansen; Jörg Behrens

    2010-01-01

    The paper overviews high energy galactic and solar cosmic ray data respectively models, which contributes to the physics behind space situational awareness (SSA) activities. The European SSA programme was signed during the ESA Ministerial Conference in November 2008. SSA activities related to Near Earth Objects (NEOs) and space weather (SW) will be explained in detail. Technological, societal economic impacts due

  20. A Search for Microwave Emission From Ultra-High Energy Cosmic Rays

    E-print Network

    Alvarez-Muñiz, J; Bogdan, M; Bohá?ová, M; Bonifazi, C; Carvalho, W R; Neto, J R T de Mello; Luis, P Facal San; Genat, J F; Hollon, N; Mills, E; Monasor, M; Privitera, P; Reyes, L C; d'Orfeuil, B Rouille; Santos, E M; Wayne, S; Williams, C; Zas, E; Zhou, J

    2012-01-01

    We present a search for microwave emission from air showers induced by ultra-high energy cosmic rays with the MIcrowave Detection of Air Showers (MIDAS) experiment. No events were found, ruling out a wide range of power flux and coherence of the putative emission, including those suggested by recent laboratory measurements.

  1. The MIDAS experiment: A prototype for the microwave emission of UltraHigh Energy Cosmic Rays

    Microsoft Academic Search

    M. Monasor; I. Alekotte; J. Alvarez-Muñiz; X. Bertou; M. Bodgan; M. Bohacova; C. Bonifazi; W. Carvalho; J. F. Genat; P. Facal San Luis; E. Mills; S. Wayne; L. C. Reyes; E. M. Santos; P. Privitera; C. Williams; E. Zas

    2011-01-01

    Recent measurements suggest that extensive air showers initiated by ultra-high energy cosmic rays (UHECR) emit signals in the microwave band of the electromagnetic spectrum caused by the collisions of the free-electrons with the atmospheric neutral molecules in the plasma produced by the passage of the shower. Such emission is isotropic and could allow the detection of air showers with 100%

  2. LAT Perspectives in Detection of High Energy Cosmic Ray Electrons

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander; Ormes, J. F.; Funk, Stefan

    2007-01-01

    The GLAST Large Area Telescope (LAT) science objectives and capabilities in the detection of high energy electrons in the energy range from 20 GeV to approx. 1 TeV are presented. LAT simulations are used to establish the event selections. It is found that maintaining the efficiency of electron detection at the level of 30% the residual hadron contamination does not exceed 2-3% of the electron flux. LAT should collect approx. ten million of electrons with the energy above 20 GeV for each year of observation. Precise spectral reconstruction with high statistics presents us with a unique opportunity to investigate several important problems such as studying galactic models of IC radiation, revealing the signatures of nearby sources such as high energy cutoff in the electron spectrum, testing the propagation model, and searching for KKDM particles decay through their contribution to the electron spectrum.

  3. Plasma Effects on Extragalactic Ultra-high-energy Cosmic Ray Hadron Beams in Cosmic Voids

    NASA Astrophysics Data System (ADS)

    Krakau, S.; Schlickeiser, R.

    2014-07-01

    The linear instability of an ultrarelativistic hadron beam (? b ? 106) in the unmagnetized intergalactic medium (IGM) is investigated with respect to the excitation of collective electrostatic and aperiodic electromagnetic fluctuations. This analysis is important for the propagation of extragalactic ultrarelativistic cosmic rays (E > 1015 eV) from their distant sources to Earth. We calculate minimum instability growth times that are orders of magnitude shorter than the cosmic ray propagation time in the IGM. Due to nonlinear effects, especially the modulation instability, the cosmic ray beam stabilizes and can propagate with nearly no energy loss through the IGM.

  4. High Energy Cosmic Neutrinos

    E-print Network

    Steven W. Barwick

    1999-03-31

    While the general principles of high-energy neutrino detection have been understood for many years, the deep, remote geographical locations of suitable detector sites have challenged the ingenuity of experimentalists, who have confronted unusual deployment, calibration, and robustness issues. Two high energy neutrino programs are now operating (Baikal and AMANDA), with the expectation of ushering in an era of multi-messenger astronomy, and two Mediterranean programs have made impressive progress. The detectors are optimized to detect neutrinos with energies of the order of 1-10 TeV, although they are capable of detecting neutrinos with energies of tens of MeV to greater than PeV. This paper outlines the interdisciplinary scientific agenda, which span the fields of astronomy, particle physics, and cosmic ray physics, and describes ongoing worldwide experimental programs to realize these goals.

  5. The Acceleration of Ultra--High-Energy Cosmic Rays in Gamma-Ray Bursts

    NASA Astrophysics Data System (ADS)

    Vietri, Mario

    1995-11-01

    Ultra-high-energy cosmic rays (UHECRs) are roughly isotropic and attain very large energies, E ? 3 × 1020 eV. Conventional models fail to explain both facts. I show here that acceleration of UHECRs in gamma-ray bursts (GRBs) satisfies both observational constraints. Using the Mészáros & Rees model (see their recent work) of GRBs as due to hyperrelativistic shocks, I show that the highest energies that can be attained thusly are E ? 1020 ?-5/3/ n15/6 eV, explaining the energy of the Bird et al. event (described in their recent work) even without beaming. The traditional photopion catastrophe affecting UHECR acceleration in active galactic nuclei is circumvented. An order of magnitude estimate shows that the total energy flux of UHECRs at Earth is also correctly reproduced. A test of the model based upon the UHECRs' distribution upon the plane of the sky is briefly discussed.

  6. Ultra-high-energy cosmic ray acceleration in engine-driven relativistic supernovae

    Microsoft Academic Search

    Sayan Chakraborti; Alak Ray; A. M. Soderberg; Abraham Loeb; Poonam Chandra

    2011-01-01

    The origin of ultra-high-energy cosmic rays (UHECRs) remains an enigma. They offer a window to new physics, including tests of physical laws at energies unattainable by terrestrial accelerators. They must be accelerated locally, otherwise, background radiations would severely suppress the flux of protons and nuclei, at energies above the Greisen-Zatsepin-Kuzmin (GZK) limit. Nearby, gamma ray bursts (GRBs), hypernovae, active galactic

  7. Angular correlation of ultra-high energy cosmic rays with compact radio-loud quasars

    NASA Astrophysics Data System (ADS)

    Virmani, Amitabh; Bhattacharya, Sibesh; Jain, Pankaj; Razzaque, Soebur; Ralston, John P.; Mckay, Douglas W.

    2002-07-01

    Angular correlations of ultra-high energy cosmic rays with cosmologically distant sources may provide clues to these mysterious events. We compare cosmic ray tracks with energies above 10 20 eV to a compilation of radio-loud compact QSO positions. The statistical method emphasizes invariant quantities and a test of statistical independence of track and source distributions. Statistical independence is ruled out by several independent statistics at confidence levels of orders 97-99%, indicating that track directions and QSO source positions are correlated at a significant level.

  8. Searching for signals of magnetic lensing in ultra-high energy cosmic rays

    NASA Astrophysics Data System (ADS)

    Golup, Geraldina; Harari, Diego; Mollerach, Silvia; Roulet, Esteban

    2011-07-01

    Ultra-high energy cosmic rays are mostly charged particles and they are therefore deflected by magnetic fields on their path from their sources to Earth. An interesting phenomenon arising from these deflections is the appearance of multiple images of a source, i.e. cosmic rays with the same energy coming from the same source that can arrive to the Earth from different directions. In this work we present a technique to identify secondary images, produced by the regular component of the galactic magnetic field, benefiting from the fact that near caustics the flux is significantly magnified.

  9. ASTROPHYSICS AND COSMOLOGY RELATED TO PARTICLES AND NUCLEI: Ultra-high energy cosmic rays threshold in Randers-Finsler space

    NASA Astrophysics Data System (ADS)

    Chang, Zhe; Li, Xin

    2009-08-01

    Kinematics in Finsler space is used to study the propagation of ultra high energy cosmic rays particles through the cosmic microwave background radiation. We find that the GZK threshold is lifted dramatically in Randers-Finsler space. A tiny deformation of spacetime from Minkowskian to Finslerian allows more ultra-high energy cosmic rays particles to arrive at the earth. It is suggested that the lower bound of particle mass is related with the negative second invariant speed in Randers-Finsler space.

  10. Modeling high-energy cosmic ray induced terrestrial muon flux: A lookup table

    E-print Network

    Dimitra Atri; Adrian L. Melott

    2011-05-09

    On geological timescales, the Earth is likely to be exposed to an increased flux of high energy cosmic rays (HECRs) from astrophysical sources such as nearby supernovae, gamma ray bursts or by galactic shocks. Typical cosmic ray energies may be much higher than the ~ 1 GeV flux which normally dominates. These high-energy particles strike the Earth's atmosphere initiating an extensive air shower. As the air shower propagates deeper, it ionizes the atmosphere by producing charged secondary particles. Secondary particles such as muons and thermal neutrons produced as a result of nuclear interactions are able to reach the ground, enhancing the radiation dose. Muons contribute 85% to the radiation dose from cosmic rays. This enhanced dose could be potentially harmful to the biosphere. This mechanism has been discussed extensively in literature but has never been quantified. Here, we have developed a lookup table that can be used to quantify this effect by modeling terrestrial muon flux from any arbitrary cosmic ray spectra with 10 GeV - 1 PeV primaries. This will enable us to compute the radiation dose on terrestrial planetary surfaces from a number of astrophysical sources.

  11. Anisotropies of ultra-high energy cosmic ray nuclei diffusing from extragalactic sources

    E-print Network

    Harari, Diego; Roulet, Esteban

    2015-01-01

    We obtain the dipolar anisotropies in the arrival directions of ultra-high energy cosmic ray nuclei diffusing from nearby extragalactic sources. We consider mixed-composition scenarios in which different cosmic ray nuclei are accelerated up to the same maximum rigidity, so that $Eenergy. We adopt $E_\\text{max}^p\\simeq 6$ EeV so as to account for an increasingly heavier composition above the ankle. We obtain the anisotropies through Monte Carlo simulations that implement the cosmic ray diffusion in extragalactic turbulent fields as well as the effects of photo-disintegrations and other energy losses. Dipolar anisotropies at the level of 5 to 10\\% at energies $\\sim 10$~EeV are predicted for plausible values of the source density and magnetic fields.

  12. Study of ultra high energy cosmic rays with the High Resolution Fly's Eye prototype detector

    NASA Astrophysics Data System (ADS)

    Song, Chihwa

    The High Resolution Fly's Eye (HiRes) detector is an air fluorescent light detector for the study of ultra high energy (>1017 eV) cosmic rays. HiRes comprises two detectors operated in a stereo mode in the dry air of the desert near Dugway, Utah. Between 1993 and 1996 one site was operated as a prototype to study the flux and average mass composition of cosmic rays between 1017 and 1019 eV. In this thesis, I study the energy spectrum and the composition of cosmic rays in this energy region. For this analysis, detector properties like the aperture and the resolution are investigated with an extensive detector simulation. In addition, I study the question whether cosmic rays at the highest energies are gamma rays, as predicted by theories explaining cosmic rays as decay products of topological defects. Several methods are proposed to discriminate gamma showers from protons and heavier nuclei. An application on HiRes monocular data shows no significant result due to lack of statistics, but in the future, the full stereo HiRes detector will unambiguously discriminate between the particle types.

  13. The Connection Between Ultra-High-Energy Cosmic Rays and Fermi Gamma-Ray Sources

    NASA Astrophysics Data System (ADS)

    Nemmen, Rodrigo; Storchi-Bergmann, T.; Bonnatto, C.

    2011-01-01

    We analyze the correlation of the positions of gamma-ray sources in the Fermi Large Area Telescope First Source Catalog (1FGL) and the First LAT Active Galactic Nuclei (AGN) Catalog (1LAC) with the arrival directions of ultra-high-energy cosmic rays (UHECRs) observed with the Pierre Auger Observatory, in order to investigate the origin of UHECRs. We find that Galactic sources and blazars identified in the 1FGL are not significantly correlated with UHECRs, while the 1LAC sources display a mild correlation (2.6sigma level) on an 2.4deg angular scale. When selecting only the 1LAC AGNs closer than 200 Mpc, we find a strong association (5.4sigma) between their positions and the directions of UHECRs on an 17deg angular scale; the probability of the observed configuration being due to an isotropic flux of cosmic rays is 5E-8. There is also a 5sigma correlation with nearby 1LAC sources on an 6.5deg scale. We identify 7 ``gamma-ray loud'' AGNs which are associated with UHECRs within 17deg and are likely candidates for the production sites of UHECRs: Centaurus A, NGC 4945, ESO 323-G77, 4C+04.77, NGC 1218, RX J0008.0+1450 and NGC 253. We interpret these results as providing additional support to the hypothesis of the origin of UHECRs in nearby extragalactic objects. As the angular scales of the correlations are large, we discuss the possibility that intervening magnetic fields might be considerably deflecting the trajectories of the particles on their way to Earth.

  14. The Need for Direct High-Energy Cosmic-Ray Measurements

    NASA Technical Reports Server (NTRS)

    Jones, Frank C.; Streitmatter, Robert

    2004-01-01

    Measuring the chemical composition of the cosmic rays in the energy region of greater than or equal to 10(exp 12)eV would be highly useful in settling several nagging questions concerning the propagation of cosmic rays in the galaxy. In particular an accurate measurement of secondary to primary ratios such as Boron to Carbon would gibe clear evidence as to whether the propagation of cosmic rays is determined by a diffusion coefficient that varies with the particle's energy as E(sup 0.5) or E(sup 0.3). This would go a long ways in helping us to understand the anistropy (or lack thereof) of the highest energy cosmic rays and the power requirements for producing those particles at approximately equal to 10(exp 18) eV which are believed to be highest energy particles produced in the Galaxy. This would be only one of the benefits of a mission such as ACCESS to perform direct particle measurements on very high energy cosmic rays.

  15. The AMY experiment to measure GHz radiation for Ultra-High Energy Cosmic Ray detection

    NASA Astrophysics Data System (ADS)

    Alvarez-Muniz, J.; Bohacova, M.; Cataldi, G.; Coluccia, M. R.; Creti, P.; De Mitri, I.; Di Giulio, C.; Engel, R.; Facal San Luis, P.; Iarlori, M.; Martello, D.; Monasor, M.; Perrone, L.; Petrera, S.; Privitera, P.; Riegel, M.; Rizi, V.; Rodriguez Fernandez, G.; Salamida, F.; Salina, G.; Settimo, M.; Smida, R.; Verzi, V.; Werner, F.; Williams, C.

    2013-02-01

    The Air Microwave Yield (AMY) project aims to measure the emission in the GHz regime from test-beam induced air-shower. The experiment is using the Beam Test Facility (BTF) of the Frascati INFN National Laboratories in Italy. The final purpose is to characterize a process to be used in a next generation of ultra-high energy cosmic rays (UHECRs) detectors. We describe the experimental apparatus and the first test performed in November 2011.

  16. The MIDAS experiment: A prototype for the microwave emission of UltraHigh Energy Cosmic Rays

    Microsoft Academic Search

    M. Monasor; I. Alekotte; J. Alvarez-Muniz; X. Bertou; M. Bodgan; M. Bohacova; C. Bonifazi; W. Carvalho; J. F. Genat; P. Facal San Luis; E. Mills; B. Rouille d'Orfeuil; S. Wayne; L. C. Reyes; E. M. Santos; P. Privitera; C. Williams; E. Zas

    2010-01-01

    Recent measurements suggest that extensive air showers initiated by\\u000aultra-high energy cosmic rays (UHECR) emit signals in the microwave band of the\\u000aelectromagnetic spectrum caused by the collisions of the free-electrons with\\u000athe atmospheric neutral molecules in the plasma produced by the passage of the\\u000ashower. Such emission is isotropic and could allow the detection of air showers\\u000awith 100%

  17. A combined cosmic ray muon spectrometer and high energy air shower array

    SciTech Connect

    Cherry, M.L.; Ayres, D.S.; Halzen, F.

    1986-01-01

    Cosmic rays have been detected at energies in excess of 10/sup 20/ eV, and individual sources have been conclusively identified as intense emitters of gamma rays at energies up to 10/sup 16/ eV. There is clearly a great deal of exciting astrophysics to be learned from such studies, but it has been suggested that there may be particle physics to be learned from the cosmic beam as well. Based in particular on the reports of surprisingly high fluxes of underground muons from the direction of Cygnus X-3 modulated by the known orbital period, there have been several suggestions recently invoking stable supersymmetric particles produced at Cygnus X-3, enhanced muon production from high energy photons, quark matter, and ''cygnets.'' Although the underground muon results have been questioned, it may still be worthwhile to consider the possibility of new physics beyond the standard model with energy scale (G/sub F/)/sup -1/2/ greater than or equal to 0.25 TeV. For example, there have been recent discussions on the experimental signatures to be observed from new high energy photon couplings to matter, exchanges between constituent quarks and leptons, and stable gluinos and photinos mixed in with the cosmic gamma ray flux. We describe here a possible detector to search for such effects. We utilize the possibility that point sources like Cygnus X-3 can be used to provide a directional time-modulated ''tagged'' high energy photon beam.

  18. Ultra High Energy Cosmic Rays from decays of Holeums in Galactic Halos

    E-print Network

    Abhijit L. Chavda; L. K. Chavda

    2008-06-03

    Stable, quantized gravitational bound states of primordial black holes called Holeums could have been produced in the early universe and could be a component of the Super Heavy Dark Matter (SHDM) present in galactic halos. We show that Holeums of masses of the order of 10**13 to 10**14 GeV and above are stable enough to survive in the present-day universe. We identify such Holeums as promising candidates for the SHDM "X-particle" and show that the decay of such Holeums by pressure ionization can give rise to cosmic rays of all observed energies, including Ultra High Energy Cosmic Rays (UHECR). The absence of the GZK cut-off is explained by the galactic halo origin of the UHECR. We predict that the cosmic rays are a manifestation of the end-stage Hawking radiation burst of the primordial black holes (PBH) liberated by the ionization of Holeums. Antimatter detected in cosmic rays could be a signature of their Holeum origin.

  19. Lunar detection of ultra-high-energy cosmic rays and neutrinos with the Square Kilometre Array

    NASA Astrophysics Data System (ADS)

    Bray, J.; Alvarez-Muniz, J.; Buitink, S.; Dagkesamanskii, R.; Ekers, R. D.; Falcke, H. D. E.; Gayley, K.; Huege, T.; James, C. W.; Mevius, M.; Mutel, R.; Protheroe, R. J.; Scholten, O.; Schroeder, F.; Spencer, R. E.; ter Veen, S.

    The origin of the most energetic particles in nature, the ultra-high-energy (UHE) cosmic rays, is still a mystery. Only the most energetic of these have sufficiently small angular deflections to be used for directional studies, and their flux is so low that even the 3,000 km^2 Pierre Auger detector registers only about 30 cosmic rays per year of these energies. A method to provide an even larger aperture is to use the lunar Askaryan technique, in which ground-based radio telescopes search for the nanosecond radio flashes produced when a cosmic ray interacts with the Moon's surface. The technique is also sensitive to UHE neutrinos, which may be produced in the decays of topological defects from the early universe. Observations with existing radio telescopes have shown that this technique is technically feasible, and established the required procedure: the radio signal should be searched for pulses in real time, compensating for ionospheric dispersion and filtering out local radio interference, and candidate events stored for later analysis. For the Square Kilometre Array (SKA), this requires the formation of multiple tied-array beams, with high time resolution, covering the Moon, with either SKA1-LOW or SKA1-MID. With its large collecting area and broad bandwidth, the SKA will be able to detect the known flux of UHE cosmic rays using the visible lunar surface - millions of square km - as the detector, providing sufficient detections of these extremely rare particles to address the mystery of their origin.

  20. The KLEM High-Energy Cosmic Ray Collector for the Nucleon Satellite Mission

    NASA Technical Reports Server (NTRS)

    Bashindzhagyan, G.; Adams, J. H., Jr.; Bashindzhagyan, P.; Chilingarian, A.; Donnelly, J.; Drury, L.; Egorov, N.; Golubkov, S.; Grebenyuk, V.; Kalinin, A.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    The basic objective of the KLEM (Kinematic Lightweight Energy Meter) Project is to directly measure the elemental energy spectra of very high-energy (10(exp 11) - 10(exp 16) eV) cosmic rays by determining the angular distribution of secondaries produced in a target layer. A small-scale version of a KLEM device has been designed for inclusion in the NUCLEON Russian satellite mission. Despite its 3 relatively small size of 36 x 36 x 30 cubic cm, this instrument has an aperture of about 0.12 square m sr and can thus make an important contribution to data concerning the elemental energy spectra of cosmic rays up to 10(exp 15) eV. Details of the experiment and the astrophysical significance of the mission will be presented.

  1. Telescope Array Radar (TARA) Observatory for Ultra-High Energy Cosmic Rays

    SciTech Connect

    Abbasi, R. [Univ. of Utah, Salt Lake City, UT (United States); Takai, H. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Allen, C. [Univ. of Kansas, Lawrence, KS (United States); Beard, L. [Purdue Univ., West Lafayette, IN (United States); Belz, J. [Univ. of Utah, Salt Lake City, UT (United States); Besson, D. [Univ. of Kansas, Lawrence, KS (United States). Moscow Engineering and Physics Inst. (Russian Federation); Byrne, M. [Univ. of Utah, Salt Lake City, UT (United States); Abou Bakr Othman, M. [Univ. of Utah, Salt Lake City, UT (United States); Farhang-Boroujeny, B. [Univ. of Utah, Salt Lake City, UT (United States); Gardner, A. [Univ. of Utah, Salt Lake City, UT (United States); Gillman, W.H. [Gillman and Associates, Salt Lake City, UT (United States); Hanlon, W. [Univ. of Utah, Salt Lake City, UT (United States); Hanson, J. [Univ. of Kansas, Lawrence, KS (United States); Jayanthmurthy, C. [Univ. of Utah, Salt Lake City, UT (United States); Kunwar, S. [Univ. of Kansas, Lawrence, KS (United States); Larson, S. L. [Utah State Univ., Logan, UT (United States); Myers, I. [Univ. of Utah, Salt Lake City, UT (United States); Prohira, S. [Univ. of Kansas, Lawrence, KS (United States); Ratzlaff, K. [Univ. of Kansas, Lawrence, KS (United States); Sokolsky, P. [Univ. of Utah, Salt Lake City, UT (United States); Thomson, G. B. [Univ. of Utah, Salt Lake City, UT (United States); Von Maluski, D. [Univ. of Utah, Salt Lake City, UT (United States)

    2014-12-01

    Construction was completed during summer 2013 on the Telescope Array RAdar (TARA) bi-static radar observatory for Ultra-High Energy Cosmic Rays (UHECR). TARA is co-located with the Telescope Array, the largest “conventional” cosmic ray detector in the Northern Hemisphere, in radio-quiet Western Utah. TARA employs an 8 MW Effective Radiated Power (ERP) VHF transmitter and smart receiver system based on a 250 MS/s data acquisition system in an effort to detect the scatter of sounding radiation by UHECR-induced atmospheric ionization. TARA seeks to demonstrate bi-static radar as a useful new remote sensing technique for UHECRs. In this report, we describe the design and performance of the TARA transmitter and receiver systems.

  2. Telescope Array Radar (TARA) Observatory for Ultra-High Energy Cosmic Rays

    DOE PAGESBeta

    Abbasi, R.; Takai, H.; Allen, C.; Beard, L.; Belz, J.; Besson, D.; Byrne, M.; Abou Bakr Othman, M.; Farhang-Boroujeny, B.; Gardner, A.; et al

    2014-12-01

    Construction was completed during summer 2013 on the Telescope Array RAdar (TARA) bi-static radar observatory for Ultra-High Energy Cosmic Rays (UHECR). TARA is co-located with the Telescope Array, the largest “conventional” cosmic ray detector in the Northern Hemisphere, in radio-quiet Western Utah. TARA employs an 8 MW Effective Radiated Power (ERP) VHF transmitter and smart receiver system based on a 250 MS/s data acquisition system in an effort to detect the scatter of sounding radiation by UHECR-induced atmospheric ionization. TARA seeks to demonstrate bi-static radar as a useful new remote sensing technique for UHECRs. In this report, we describe themore »design and performance of the TARA transmitter and receiver systems.« less

  3. PARSEC: A Parametrized Simulation Engine for Ultra-High Energy Cosmic Ray Protons

    E-print Network

    Bretz, Hans-Peter; Schiffer, Peter; Walz, David; Winchen, Tobias

    2013-01-01

    We present a new simulation engine for fast generation of ultra-high energy cosmic ray data based on parametrizations of common assumptions of UHECR origin and propagation. Implemented are deflections in unstructured turbulent extragalactic fields, energy losses for protons due to photo-pion production and electron-pair production, as well as effects from the expansion of the universe. Additionally, a simple model to estimate propagation effects from iron nuclei is included. Deflections in galactic magnetic fields are included using a matrix approach with precalculated lenses generated from backtracked cosmic rays. The PARSEC program is based on object oriented programming paradigms enabling users to extend the implemented models and is steerable with a graphical user interface.

  4. Monocular measurement of the ultra-high energy cosmic ray spectrum

    NASA Astrophysics Data System (ADS)

    Shah, Priti Dhanesh

    The Telescope Array Project was designed to observe cosmic rays with energies greater than 1018 eV. Its goals are to study the physics of cosmic rays by measuring their anisotropy, composition, and energy spectrum. This work makes a monocular measurement of the ultra high energy cosmic ray spectrum and analyzes the physics produced from that spectrum. The flux of cosmic rays observed on Earth follows a power law over 12 decades in energy and 32 decades in flux. At the highest energies, the spectrum has detailed structure. Studying these features can tell us about the astrophysics of the production and propagation of cosmic rays. First, it can tell us about the sources of cosmic rays such as they capable of producing a power law spectrum and the maximum energy of cosmic rays that they can produce. Second, the acceleration mechanisms that can boost cosmic rays to ultra high energies can be studied. Third, the spectral features themselves can tell us about their possible cause for formation. For example, the ankle feature in the ultra high energy regime can tell us if it is the galactic-extragalactic transition or if it is due to e+e- pair production. Fourth, the energy losses that cosmic rays incur can tell us about their physical interactions during propagation. Studying the physics of the cosmic ray spectrum in the ultra high energy regime with data from the Telescope Array Project is the goal of this analysis. The Telescope Array Project consists of three fluorescence detectors overlooking an array of 507 scintillation surface detectors. Due to their extremely low flux at these energies, cosmic rays can only be observed indirectly via an extensive air shower produced when they collide with the nucleus of an atom in the Earth's atmosphere. These charged secondary particles produce fluorescence light. The array of surface detectors observes the lateral footprint of the extensive air shower when it reaches the ground. The fluorescence detectors observe the longitudinal profile of this fluorescence light. This thesis analyzes the data from one of the fluorescence detectors, Middle Drum, using a different geometry reconstruction technique, the Time versus Angle geometry. The results of this analysis show an ultra high energy cosmic ray spectrum that is consistent with the results previously published by the High Resolution Fly's Eye (HiRes) experiment, the Telescope Array surface detectors, and other experiments in this energy region. Due to insufficient statistics at this date, the GZK cutoff cannot be confirmed in this analysis, but a fit shows the cutoff to be at log10 E (E/eV) = 19.56 ± 0.36, with a spectral index after the cutoff of - 3.86 ± 2.0. This is within the range determined previously by other measurements. This analysis shows that the feature known as the ankle occurs at log10 E (E/eV) = 18.63 ± 0.09, with a spectral index of - 3.27 ± 0.07 before the ankle and a spectral index of - 2.81 ± 0.10 after the ankle. The normalized log likelihood per degree of freedom is 0.90. The ankle is observed at the 4 — 5 ? confidence level. The fit to the ankle is also in excellent agreement with previous measurements, and even more remarkable given that some other measurements use different techniques. While this study cannot tell us information about the sources or the acceleration mechanisms of cosmic rays, it does show us a feature and tell us about energy losses during propagation. The dip at the ankle is clearly visible in the spectrum. The results of this study are consistent with the energy loss model of extragalactic protons interacting with the cosmic microwave background radiation and supports the idea that the ankle is excavated due to e+e- pair production. The location of the ankle at a threshold greater than for e+e- pair production supports that the ankle is a composite feature where the redshift energy losses begin to dominate the e+e- pair production losses. The location of the ankle also implies that sources at larger distances than the GZK cutoff contribute to its formation.

  5. Effects of Cosmic Infrared Background on High Energy Delayed Gamma-Rays From Gamma-Ray Bursts

    SciTech Connect

    Murase, Kohta; /Kyoto U., Yukawa Inst., Kyoto; Asano, Katsuaki; /Natl. Astron. Observ. of Japan; Nagataki, Shigehiro; /Kyoto U., Yukawa Inst., Kyoto /KIPAC, Menlo Park

    2007-04-06

    Regenerated high energy emissions from gamma-ray bursts (GRBs) are studied in detail. If the primary emission spectrum extends to TeV range, these very high energy photons will be absorbed by the cosmic infrared background (CIB). The created high energy electron-positron pairs up-scatter not only cosmic microwave background (CMB) photons but also CIB photons, and secondary photons are generated in the GeV-TeV range. These secondary delayed photons may be observed in the near future, and useful for a consistency check for the primary spectra and GRB physical parameters. The up-scattered CIB photons cannot be neglected for low redshift bursts and/or GRBs with a relatively low maximum photon energy. The secondary gamma-rays also give us additional information on the CIB, which is uncertain in observations so far.

  6. Susy QCD and High Energy Cosmic Rays 1. Fragmentation functions of Susy QCD

    E-print Network

    Claudio Coriano'; Alon E. Faraggi

    2002-01-07

    The supersymmetric evolution of the fragmentation functions (or timelike evolution) within N=1 $QCD$ is discussed and predictions for the fragmentation functions of the theory (into final protons) are given. We use a backward running of the supersymmetric DGLAP equations, using a method developed in previous works. We start from the usual QCD parameterizations at low energy and run the DGLAP back, up to an intermediate scale -assumed to be supersymmetric- where we switch-on supersymmetry. From there on we assume the applicability of an N=1 supersymmetric evolution (ESAP). We elaborate on possible application of these results to High Energy Cosmic Rays near the GZK cutoff.

  7. The UH-nuclei cosmic ray detector on the third High Energy Astronomy Observatory

    NASA Technical Reports Server (NTRS)

    Binns, W. R.; Israel, M. H.; Klarmann, J.; Scarlett, W. R.; Waddington, C. J.; Stone, E. C.

    1981-01-01

    The third High Energy Astronomy Observatory satellite (HEAO-3) carries a particle telescope for the detection of highly charged cosmic ray nuclei. These nuclei, which have Z equal to or greater than 28, are much rarer than the lower charged nuclei in the cosmic radiation. As a consequence, this particle telescope was required to have a large collecting area as well as an ability to resolve individual elements. This paper describes the telescope, composed of large area parallel plate ionization chambers, multiwire ion chamber hodoscopes and a Cherenkov radiation detector. The resulting telescope has a total geometry factor of 59,000 sq cm sr and is capable of measuring the charges of nuclei in the range Z = 14-120.

  8. Extragalactic ultra high energy cosmic rays, II. Comparison with experimental data

    E-print Network

    Joerg P. Rachen; Todor Stanev; Peter L. Biermann

    1993-02-04

    We compare the expected contribution of FR-II hot spots to the ultra-high energy cosmic ray spectrum (Rachen & Biermann 1993, A&A in press, BB paper astro-ph/9301010) to improved experimental results. We introduce a "world data set" of UHE cosmic rays by comparing the data of various experiments, extracting relative systematic errors in the energy derivation and averaging over energy bins. Since the contribution of FR-II hot spots is expected to be dominated by protons, we can also compare it to the recent experimental results for the proton component of cosmic rays between 0.1 and 1 EeV from both the Fly's Eye and the Akeno airshower detector (Gaisser et al. 1993, Phys Rev D in press, and Stanev et al. 1992, A&A submitted). The result is striking: Our prediction for energies below 1 EeV fits very well to the data for the proton component, while explaining the total flux at highest energies as well. The result is consistent with the expectation of a galactic component, consisting of heavy nuclei only, that has a slope of about -3.1 and cuts off at 5 EeV, as predicted by Biermann 1993 (A&A in press, BB paper astro-ph/9301008)

  9. Ultra-high-energy cosmic ray acceleration in engine-driven relativistic supernovae.

    PubMed

    Chakraborti, S; Ray, A; Soderberg, A M; Loeb, A; Chandra, P

    2011-01-01

    The origin of ultra-high-energy cosmic rays (UHECRs) remains an enigma. They offer a window to new physics, including tests of physical laws at energies unattainable by terrestrial accelerators. They must be accelerated locally, otherwise, background radiations would severely suppress the flux of protons and nuclei, at energies above the Greisen-Zatsepin-Kuzmin (GZK) limit. Nearby, gamma ray bursts (GRBs), hypernovae, active galactic nuclei and their flares have all been suggested and debated as possible sources. A local sub-population of type Ibc supernovae (SNe) with mildly relativistic outflows have been detected as sub-energetic GRBs, X-ray flashes and recently as radio afterglows without detected GRB counterparts. Here, we measure the size-magnetic field evolution, baryon loading and energetics, using the observed radio spectra of SN 2009bb. We place such engine-driven SNe above the Hillas line and establish that they can readily explain the post-GZK UHECRs. PMID:21285953

  10. Production of high-energy gamma rays by cosmic ray interactions in the atmosphere and lunar surface

    NASA Technical Reports Server (NTRS)

    Morris, D. J.

    1984-01-01

    The production of gamma rays above 10 MeV by the interaction of cosmic rays in the atmosphere and the lunar surface is simulated using Monte Carlo methods. The calculation incorporates a new model of high-energy nucleon-nucleus interactions based on empirical fits to inclusive cross sections for the production of pions and nucleons. The atmospheric gamma ray flux is calculated as a function of direction, energy, and atmospheric depth. These calculations are compared with observations from balloons and from the SAS 2 satellite. Estimates of the flux of earth albedo electrons produced by cosmic ray interactions are presented. The lunar gamma ray albedo is calculated and compared with an upper limit based on SAS 2 measurements.

  11. A high energy Space Station (HESS) array for studying extremely energetic cosmic rays

    NASA Technical Reports Server (NTRS)

    Ormes, J. F.; Streitmatter, R. E.

    1985-01-01

    The scientific aims and design concept of a High-Energy Space Station (HESS) cosmic-ray detector array are discussed. The current state of knowledge on cosmic-ray acceleration and high-energy interactions is briefly reviewed, and the need for observations yielding elemental composition and spectra in the 10-10,000-TeV/nucleon range is demonstrated. It is predicted that 2 yr of observations with a space-borne detector of geometry factor 30 sq m sr would provide adequate data to determine the acceleration mechanism (by comparing the energy level at which the spectra of He nuclei and protons break). A modular HESS array comprising W/scintillator/PM-tube calorimeter modules and Cerenkov charge-sensitive detector modules and weighing about 30 tonnes is described. The array could be assembled on orbit after transport in the Space Shuttle cargo bay, and data could be taken as soon as one or two layers of modules had been attached to the mounting-frame/support-electronics unit.

  12. Ultra high energy cosmic rays: implications of Auger data for source spectra and chemical composition

    NASA Astrophysics Data System (ADS)

    Aloisio, R.; Berezinsky, V.; Blasi, P.

    2014-10-01

    We use a kinetic-equation approach to describe the propagation of ultra high energy cosmic ray protons and nuclei and calculate the expected spectra and mass composition at the Earth for different assumptions on the source injection spectra and chemical abundances. When compared with the spectrum, the elongation rate Xmax(E) and dispersion ?(Xmax) as observed with the Pierre Auger Observatory, several important consequences can be drawn: a) the injection spectra of nuclei must be very hard, ~ E-? with ?~ 1- 1.6; b) the maximum energy of nuclei of charge Z in the sources must be ~ 5Z× 1018 eV, thereby not requiring acceleration to extremely high energies; c) the fit to the Auger spectrum can be obtained only at the price of adding an ad hoc light extragalactic component with a steep injection spectrum ~ E-2.7). In this sense, at the ankle EA? 5× 1018 eV) all the components are of extragalactic origin, thereby suggesting that the transition from Galactic to extragalactic cosmic rays occurs below the ankle. Interestingly, the additional light extragalactic component postulated above compares well, in terms of spectrum and normalization, with the one recently measured by KASCADE-Grande.

  13. Interactions of High Energy Cosmic Rays with Extragalactic Infrared Radiation Background

    E-print Network

    E. V. Bugaev; P. A. Klimai

    2005-09-14

    We consider the modification of extragalactic cosmic ray spectrum caused by cosmic ray interactions with infrared background photons which are present in the extragalactic space together with relic photons. It is assumed that cosmic ray spectrum at superhigh energies has extragalactic origin and is proton dominated.

  14. Fast Neutron - Mirror Neutron Oscillation and Ultra High Energy Cosmic Rays

    E-print Network

    Zurab Berezhiani; Luis Bento

    2006-02-24

    If there exists the mirror world, a parallel hidden sector of particles with exactly the same microphysics as that of the observable particles, then the primordial nucleosynthesis constraints require that the temperature of the cosmic background of mirror relic photons should be smaller than that of the ordinary relic photons, T'/T neutron - mirror neutron oscillation in vacuum, with an oscillation time $\\tau \\sim 1$ s, much smaller than the neutron lifetime. We show that this could provide a very efficient mechanism for transporting ultra high energy protons at large cosmological distances. The mechanism operates as follows: a super-GZK energy proton scatters a relic photon producing a neutron that oscillates into a mirror neutron which then decays into a mirror proton. The latter undergoes a symmetric process, scattering a mirror relic photon and producing back an ordinary nucleon, but only after traveling a distance $(T/T')^{3}$ times larger than ordinary protons. This may relax or completely remove the GZK-cutoff in the cosmic ray spectrum and also explain the correlation between the observed ultra high energy protons and far distant sources as are the BL Lacs.

  15. Study of high energy cosmic ray interactions and primary composition using mountain based detectors

    Microsoft Academic Search

    Y. Fujimoto; V. Kopenkin; A. Ohsawa; M. Tamada; C. E. Navia; C. R. A. Augusto; A. K. Managadze; T. M. Roganova; I. V. Rakobolskaya; L. G. Sveshnikova

    2001-01-01

    We report new experimental results obtained by MSU-Waseda collaboration. Our detector is 60 cm thick lead X-ray emulsion chamber exposed to cosmic rays at Pamirs. We show that this experiment can detect cosmic rays in the wide energy range 1013 - 1017 eV. Using experimental data we discuss the primary cosmic ray composition and the features of hadron interactions in

  16. Magnetic diffusion effects on the ultra-high energy cosmic ray spectrum and composition

    NASA Astrophysics Data System (ADS)

    Mollerach, Silvia; Roulet, Esteban

    2013-10-01

    We discuss the effects of diffusion of high energy cosmic rays in turbulent extra-galactic magnetic fields. We find an approximate expression for the low energy suppression of the spectrum of the different mass components (with charge Z) in the case in which this suppression happens at energies below ~ Z EeV, so that energy losses are dominated by the adiabatic ones. The low energy suppression appears when cosmic rays from the closest sources take a time comparable to the age of the Universe to reach the Earth. This occurs for energies E < Z EeV (B/nG)?(lc/Mpc)(ds/70Mpc) in terms of the magnetic field RMS strength B, its coherence length lc and the typical separation between sources ds. We apply this to scenarios in which the sources produce a mixed composition and have a relatively low maximum rigidity (Emax ~ (2-10)Z EeV), finding that diffusion has a significant effect on the resulting spectrum, the average mass and on its spread, in particular reducing this last one. For reasonable values of B and lc these effects can help to reproduce the composition trends observed by the Auger Collaboration for source spectra compatible with Fermi acceleration.

  17. Energy Spectrum of Ultra High Energy Cosmic Ray Showers Using Hybrid Analysis from Telescope Array

    NASA Astrophysics Data System (ADS)

    Allen, Monica; Abu-Zayyad, Tareq; Stokes, Benjamin

    2011-10-01

    The Telescope Array studies ultra high energy cosmic rays using a hybrid detector. Fluorescence telescopes measure the longitudinal development of the extensive air shower generated by a primary cosmic ray particle, while scintillator detectors measure the lateral distribution of secondary particles that hit the ground. The Middle Drum (MD) fluorescence telescope consists of 14 refurbished telescopes from the High Resolution Fly's Eye experiment (HiRes), providing a direct link back to the HiRes experiment and data. Using the scintillator detector data in conjunction with the MD data improves the geometrical reconstruction of the showers significantly, and hence, provides a more accurate reconstruction of the energy of the primary particle. The method for determining the spectrum will be described. The event selection and reconstruction process, along with the Monte Carlo simulation used for calculating the detector aperture and exposure will also be discussed. Detector resolutions and comparisons between Monte Carlo and data distributions of key variables that contribute to the aperture will be shown to validate the simulation. Finally, the resulting hybrid spectrum obtained from the Middle Drum fluorescence detector will be presented.

  18. Extensive air showers and ultra high-energy cosmic rays: a historical review

    NASA Astrophysics Data System (ADS)

    Kampert, Karl-Heinz; Watson, Alan A.

    2012-08-01

    The discovery of extensive air showers by Rossi, Schmeiser, Bothe, Kohlhörster and Auger at the end of the 1930s, facilitated by the coincidence technique of Bothe and Rossi, led to fundamental contributions in the field of cosmic ray physics and laid the foundation for high-energy particle physics. Soon after World War II a cosmic ray group at MIT in the USA pioneered detailed investigations of air shower phenomena and their experimental skill laid the foundation for many of the methods and much of the instrumentation used today. Soon interests focussed on the highest energies requiring much larger detectors to be operated. The first detection of air fluorescence light by Japanese and US groups in the early 1970s marked an important experimental breakthrough towards this end as it allowed huge volumes of atmosphere to be monitored by optical telescopes. Radio observations of air showers, pioneered in the 1960s, are presently experiencing a renaissance and may revolutionise the field again. In the last 7 decades the research has seen many ups but also a few downs. However, the example of the Cygnus X-3 story demonstrated that even non-confirmable observations can have a huge impact by boosting new instrumentation to make discoveries and shape an entire scientific community.

  19. Lorentz invariance violation and chemical composition of ultra high energy cosmic rays

    SciTech Connect

    Saveliev, Andrey; Sigl, Guenter [II. Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Maccione, Luca, E-mail: andrey.saveliev@desy.de, E-mail: luca.maccione@desy.de, E-mail: guenter.sigl@desy.de [DESY Theory Group, Notkestraße 85, 22607 Hamburg (Germany)

    2011-03-01

    Motivated by experimental indications of a significant presence of heavy nuclei in the cosmic ray flux at ultra high energies (?>10{sup 19} eV), we consider the effects of Planck scale suppressed Lorentz Invariance Violation (LIV) on the propagation of cosmic ray nuclei. In particular we focus on LIV effects on the photodisintegration of nuclei onto the background radiation fields. After a general discussion of the behavior of the relevant quantities, we apply our formalism to a simplified model where the LIV parameters of the various nuclei are assumed to kinematically result from a single LIV parameter for the constituent nucleons, ?, and we derive constraints on ?. Assuming a nucleus of a particular species to be actually present at 10{sup 20} eV the following constraints can be placed: ?3 × 10{sup ?2}?

  20. The mass composition of ultra-high energy cosmic rays with the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Martraire, D.

    2014-12-01

    Ultra-high energy cosmic rays are the most energetic particles known in nature. The Pierre Auger Observatory was built to study these amazing particles to determine their origin. The study of their mass composition can help to constrain the models concerning their origins and their production mechanisms in the astrophysical sources. To this aim, several methods have been developed to infer the composition using the Auger surface detector array data. The main difficulty is to isolate the muonic component in the signal measured by the surface detector. We present the results of the composition parameters derived from the ground level component and compare them to the predictions for different nuclear masses of the primary particles and hadronic interaction models.

  1. Ultra High Energy Cosmic Rays and Air Shower Simulations: a top-bottom view

    E-print Network

    Alessandro Cafarella; Claudio Coriano; Alon E. Faraggi

    2003-06-26

    Stable Superstring Relics (SSR) provide some of the candidates for the possible origin of the Ultra High Energy Cosmic Rays (UHECR). After a brief overview of the motivations for introducing such relics, we address the question whether statistical fluctuations in the formation of the air showers generated by the primary spectrum of protons can be separated from a possible signal of new physics hidden in the first impact with the atmosphere. Our results are generated by using minimal modifications in the cross section of the primaries, and using available simulation codes used by the experimental collaborations. The results indicate that substantial increases in the cross section of the first impact, possibly due to new interactions, are unlikely to be detected in geometrical and/or variations of multiplicities in the cascade.

  2. Mass composition of high-energy cosmic rays and scaling violation in their interactions

    NASA Astrophysics Data System (ADS)

    Wdowczyk, J.; Wolfendale, A. W.

    1983-11-01

    Published results of proton-antiproton-collider experiments at energies of about 200 TeV (Kafka et al., 1977; Vernov et al., 1977) and EAS observations (Hara et al., 1981; Danilova et al., 1981) are analyzed in terms of theoretical models of the mass composition of high-energy cosmic rays. The scaling model with an asymptotic condition at about 100 GeV requires a different mass composition at higher energies, but this is not confirmed by the experimental and observational data, which are summarized and presented graphically. Deviation from scaling is shown to increase with increasing energy from 1 to 100 TeV and to continue up to about 10 PeV, but to be less severe above 100 PeV, in general agreement with the changing-interactive-characteristic model of Olejniczak et al. (1977).

  3. Japanese-American Cooperative Emulsion Experiment /JACEE/. [high energy cosmic ray studies

    NASA Technical Reports Server (NTRS)

    Huggett, R. W.; Hunter, S. D.; Jones, W. V.; Takahashi, Y.; Ogata, T.; Saito, T.; Holynski, R.; Jurak, A.; Wolter, W.; Parnell, T. A.

    1981-01-01

    The instrumentation and results of long duration balloon flights carried out jointly by U.S. and Japan researchers to examine high energy cosmic rays are reported. Basic detector geometries are 2.5 sq m sr with operation at altitudes with 3-4 g/sq cm pressure, with observations thus far of over 100 hr. Energies from 2-100 TeV are recorded for nucleus-nucleus and hadron-nucleus interactions, and searches are made for new particle or interactions. The detector is an emulsion chamber which comprises doubly-coated nuclear emulsions on 800 micron thick methacryl substrates, X-ray films, etchable detectors, low density spacers, and lead sheets. Segmentation of the instrument into a primary charge module, a target section, a spacer section, and a lead-emulsion calorimeter allows accurate charge measurement for primary nuclei, reliable energy resolution, and a large geometrical factor for collecting high energy events. A primary Ca nucleus of 300 TeV has been observed.

  4. CREAM-Pushing the high energy frontier of directly measured cosmic rays

    Microsoft Academic Search

    O. Ganel; H. S. Ahn; P. Allison; M. G. Bagliesi; J. J. Beatty; G. Bigongiari; P. Boyle; J. T. Childers; N. B. Conklin; S. Coutu; M. A. Duvernois; J. H. Han; H. J. Hyun; J. A. Jeon; K. C. Kim; J. K. Lee; M. H. Lee; L. Lutz; P. Maestro; A. Malinin; P. S. Marrocchesi; S. Minnick; S. I. Mognet; S. W. Nam; S. Nutter; I. H. Park; N. H. Park; E. S. Seo; S. Swordy; R. Sina; S. Wakely; J. Wu; J. Yang; R. Zei; S. Y. Zinn

    2006-01-01

    After nearly a century since their discovery, much is still uncertain about cosmic rays, including their source, acceleration\\u000a mechanism, and propagation. Direct measurement of cosmic-ray elemental spectra in the critical energy range of 1012–1015 eV offers a promising avenue to answering these questions. The Cosmic Ray Energetics And Mass (CREAM) experiment was launched\\u000a from McMurdo Station, Antarctica, under a NASA

  5. High energy irradiations simulating cosmic-ray-induced planetary gamma ray production. I - Fe target

    NASA Technical Reports Server (NTRS)

    Metzger, A. E.; Parker, R. H.; Yellin, J.

    1986-01-01

    Two thick Fe targets were bombarded by a series of 6 GeV proton irradiations for the purpose of simulating the cosmic ray bombardment of planetary objects in space. Gamma ray energy spectra were obtained with a germanium solid state detector during the bombardment, and 46 of the gamma ray lines were ascribed to the Fe targets. A comparison between observed and predicted values showed good agreement for Fe lines from neutron inelastic scattering and spallation reactions, and less satisfactory agreement for neutron capture reactions, the latter attributed to the difference in composition between the Fe target and the mean lunar abundance used in the modeling. Through an analysis of the irradiation results together with continuum data obtained in lunar orbit, it was found that 100 hours of measurement with a current instrument should generate a spectrum containing approximately 20 lines due to Fe alone, with a 2-sigma sensitivity for detection of about 0.2 percent.

  6. Astrophysics of Ultra-High Energy Cosmic Rays, Photons, and Neutrinos

    NASA Astrophysics Data System (ADS)

    Mészáros, Peter; Watson, Alan; Waxman, Eli

    2005-05-01

    This miniworkshop concentrates on the astrophysics of GeV to ZeV cosmic rays, photons and neutrinos from active galaxies, gamma ray bursts and other compact or diffuse sources, as well as the transport processes and the physics of acceleration mechanisms that determine their observed fluxes and spectra. SCIENCE and MOTIVATION There are a number of major issues which this workshop is aimed at: * What is the origin of the ultra-high energy(PeV to ZeV) cosmic rays? Independently of whether there are super-GZK events or not, the CR flux levels near 1E20 eV from AGASA and HIRES are within 3 sigma of each other, and there is an intense debate about the possible astrophysical sources. What is the contribution to these from gamma-ray bursts, active galaxies, galactic core sources? Can we reconcile the AGASA and HIRES discrepancies? Can Fermi acceleration explain particles at the GZK limit, and can we test shock acceleration? How strong is the case for alternative astrophysical acceleration mechanisms? What are the implications of Auger's accumulating data, as the array progresses towards completion? What can be learned about intergalactic matter from cosmic ray propagation effects? * What is the origin of GeV-TeV photons from AGN, GRB, SNRs? Are the jets in AGN and GRB hadronic or leptonic? What constraints can be imposed on these from TeV and correlated lower energy spectra and variability? What is the origin of the GeV-TeV emission from pulsars and possibly magnetars(polar cap or outer gap emittors?) Are there smoking gun signatures of Fermi(diffusive) or other, e.g. linear(wakefield, etc) acceleration of leptons? For scattering off magnetic turbulence, reconnection, etc? Is there strong evidence for proton acceleration and hadronic cascades? How realistic is it to detect gamma-ray signatures of the quantum-gravity energy scale, vacuum dispersion, etc., with GLAST, SWIFT, etc? * What is the TeV to EeV neutrino emission of AGN, GRB, micro- quasars and other sources? How will it take for AMANDA to set limits on the diffuse neutrino flux from these? What can we learn about interactions at > TeV CM energies from atmospheric or point source neutrinos with Auger and ICECUBE? Can we detect UHE tau neutrinos, and what will we learn from them? How far can TeV-nu measurements constrain the neutrino masses, mixing angles, etc?

  7. Gamma-Ray Bursts and Magnetars as Possible Sources of Ultra High Energy Cosmic Rays: Correlation of Cosmic Ray Event Positions with IRAS Galaxies

    E-print Network

    Shwetabh Singh; Chung-Pei Ma; Jonathan Arons

    2004-02-05

    We use the two-dimensional Kolmogorov-Smirnov (KS) test to study the correlation between the 60 cosmic ray events above 4x10^19 eV from the AGASA experiment and the positions of infrared luminous galaxies from the IRAS PSCz catalog. These galaxies are expected to be hosts to gamma ray bursts (GRB) and magnetars, both of which are associated with core collapse supernovae and have been proposed as possible acceleration sites for ultra high energy cosmic rays. We find consistency between the models and the AGASA events to have been drawn from the same underlying distribution of positions on the sky with KS probabilities ~50%. Application of the same test to the 11 highest AGASA events above 10^20 eV, however, yields a KS probability of 99.5% significance level. Taken at face value, these highest energy results suggest that the existing cosmic ray events above 10^20 eV do not owe their origin to long burst GRBs, rapidly rotating magnetars, or any other events associated with core collapse supernovae. The larger data set expected from the AUGER experiment will test whether this conclusion is real or is a statistical fluke that we estimate to be at the 2 sigma level.

  8. Patterns in ultra-high energy cosmic ray arrival directions: a possible footprint of large scale cosmic structures

    SciTech Connect

    Serpico, Pasquale Dario; /Fermilab

    2007-07-01

    The public available data of cosmic ray arrival directions with energies above 4 x 10{sup 19} eV present a broad maximum in the cumulative two-point autocorrelation function around 25 degrees. This has been interpreted as the first imprint of the filamentary pattern of large scale structures (LSS) of matter in the near universe. We analyze this suggestion in light of the clustering properties expected from a catalogue of galaxies of the local universe (redshift z {approx}< 0:06). The data reproduce particularly well the clustering properties of the nearby universe within z {approx}< 0:02. There is no statistically significant cross-correlation between data and structures, although intriguingly the nominal cross-correlation chance probability for displacements within {approx}50 degree drops from O(50%) to O(10%) using the catalogue with a smaller horizon. Our results suggest a relevant role of magnetic fields (possibly extragalactic ones, too) and/or possibly some heavy nuclei fraction in the ultra-high energy cosmic rays.

  9. Perturbations to aquatic photosynthesis due to high-energy cosmic ray induced muon flux in the extragalactic shock model

    NASA Astrophysics Data System (ADS)

    Rodriguez, Lien; Cardenas, Rolando; Rodriguez, Oscar

    2013-10-01

    We modify a mathematical model of photosynthesis to quantify the perturbations that high energy muons could make on aquatic primary productivity. Then, we apply this in the context of the extragalactic shock model, according to which Earth receives an enhanced dose of high-energy cosmic rays when it is at the galactic north. We obtain considerable reduction in the photosynthesis rates, consistent with potential drops in biodiversity.

  10. Monitoring system for high energy cosmic ray observation in space environment using advanced electro-optic Pockels techniques

    Microsoft Academic Search

    Hiroko SAITO; Toshiaki URABE; Yasuhiro TANAKA; Tatsuo TAKADA; Y. Murooka; N. Tomita

    2000-01-01

    In order to monitor high-energy cosmic rays in a space environment, we succeeded initially in measuring the 2-dimensional birefringence produced due to space charges in dielectric material using a Pockels effect. If high-energy charged particles penetrate into the Pockels crystal and accumulate in it, 2-dimensional birefringence properties are formed in the crystal. In this paper, we introduce the experimental results

  11. Ultra-high-energy cosmic rays from black hole jets of radio galaxies

    NASA Astrophysics Data System (ADS)

    Dermer, C. D.; Razzaque, S.; Finke, J. D.; Atoyan, A.

    2009-06-01

    The Auger Collaboration reports (Auger Collaboration 2007 Science 318 939, The Pierre Auger Collaboration 2008 Astropart. Phys. 29 188) that the arrival directions of gsim60 EeV ultra-high-energy cosmic rays (UHECRs) cluster along the supergalactic plane and correlate with active galactic nuclei (AGN) within ? 100 Mpc. The association of several events with the nearby radio galaxy Centaurus A supports the paradigm that UHECRs are powered by supermassive black-hole engines and accelerated to ultra-high energies in the shocks formed by variable plasma winds in the inner jets of radio galaxies. The GZK horizon length of 75 EeV UHECR protons is ?100 Mpc, so that the Auger results are consistent with an assumed proton composition of the UHECRs. In this scenario, the sources of UHECRs are FR II radio galaxies and FR I galaxies like Cen A with scattered radiation fields that enhance UHECR neutral-beam production. Radio galaxies with jets pointed away from us can still be observed as UHECR sources due to deflection of UHECRs by magnetic fields in the radio lobes of these galaxies. A broadband ~1 MeV-10 EeV radiation component in the spectra of blazar AGN is formed by UHECR-induced cascade radiation in the extragalactic background light. This emission is too faint to be seen from Cen A, but could be detected from more luminous blazars.

  12. Energy reconstruction of hadron-initiated showers of ultra-high energy cosmic rays

    NASA Astrophysics Data System (ADS)

    Ros, G.; Medina-Tanco, G. A.; Supanitsky, A. D.; del Peral, L.; Rodríguez-Frías, M. D.

    2015-09-01

    The current methods to determine the primary energy of ultra-high energy cosmic rays (UHECRs) are different when dealing with hadron or photon primaries. The current experiments combine two different techniques, an array of surface detectors and fluorescence telescopes. The latter allow an almost calorimetric measurement of the primary energy. Thus, hadron-initiated showers detected by both type of detectors are used to calibrate the energy estimator from the surface array (usually the interpolated signal at a certain distance from the shower core S (r0)) with the primary energy. On the other hand, this calibration is not feasible when searching for photon primaries since no high energy photon has been unambiguously detected so far. Therefore, pure Monte Carlo parametrizations are used instead. In this work, we present a new method to determine the primary energy of hadron-induced showers in a hybrid experiment based on a technique previously developed for photon primaries. It consists on a set of calibration curves that relate the surface energy estimator, S (r0) , and the depth of maximum development of the shower, Xmax , obtained from the fluorescence telescopes. Then, the primary energy can be determined from pure surface information since S (r0) and the zenith angle of the incoming shower are only needed. Considering a mixed sample of ultra-high energy proton and iron primaries and taking into account the reconstruction uncertainties and shower to shower fluctuations, we demonstrate that the primary energy may be determined with a systematic uncertainty below 1% and resolution around 16% in the energy range from 1018.5 to 1019.6 eV. Several array geometries, the shape of the energy error distributions and the uncertainties due to the unknown composition of the primary flux have been analyzed as well.

  13. Future use of silicon photomultipliers for the fluorescence detection of ultra-high-energy cosmic rays

    NASA Astrophysics Data System (ADS)

    Stephan, Maurice; Hebbeker, Thomas; Lauscher, Markus; Meurer, Christine; Niggemann, Tim; Schumacher, Johannes

    2011-10-01

    A sophisticated technique to measure extensive air showers initiated by ultra-high-energy cosmic rays is by means of fluorescence telescopes. Secondary particles of the air shower excite nitrogen molecules of the atmosphere, which emit fluorescence light when they de-excite. Due to their high photon detection efficiency (PDE) silicon photomultipliers (SiPMs) promise to increase the sensitivity of todays fluorescence telescopes which use photomultiplier tubes - for example the fluorescence detector of the Pierre Auger Observatory. On the other hand drawbacks like a small sensitive area, a strong temperature dependency and a high noise rate have to be managed. We present plans for a prototype fluorescence telescope using SiPMs and a special light collecting optical system of Winston cones to increase the sensitive area. In this context we made measurements of the relative PDE of SiPMs depending on the incident angle of light. The results agree with calculations based on the Fresnel equations. Furthermore, measurements of the brightness of the night sky are presented since this photon flux is the main background to the fluorescence signals of the extensive air showers. To compensate the temperature dependency of the SiPM, frontend electronics make use of temperature sensors and microcontrollers to directly adjust the bias-voltage according to the thermal conditions. To reduce the noise rate we study the coincidence of several SiPMs signals triggered by cosmic ray events. By summing up these signals the SiPMs will constitute a single pixel of the fluorescence telescope.

  14. Engine-driven Relativistic Supernovae as Sources of Ultra High Energy Cosmic Rays

    Microsoft Academic Search

    Alak Ray; Sayan Chakraborti

    2011-01-01

    Understanding the origin of the highest energy cosmic rays is a crucial step in probing new physics at energies unattainable by terrestrial accelerators. Their sources remain an enigma half a century after their discovery. They must be accelerated in the local universe as otherwise interaction with cosmic background radiations would severely deplete the flux of protons and nuclei at energies

  15. Full sky harmonic analysis hints at large ultra-high energy cosmic ray deflections

    NASA Astrophysics Data System (ADS)

    Tinyakov, P. G.; Urban, F. R.

    2015-03-01

    The full-sky multipole coefficients of the ultra-high energy cosmic ray (UHECR) flux have been measured for the first time by the Pierre Auger and Telescope Array collaborations using a joint data set with E > 10 EeV. We calculate these harmonic coefficients in the model where UHECR are protons and sources trace the local matter distribution, and compare our results with observations. We find that the expected power for low multipoles (dipole and quadrupole, in particular) is sytematically higher than in the data: the observed flux is too isotropic. We then investigate to which degree our predictions are influenced by UHECR deflections in the regular Galactic magnetic field. It turns out that the UHECR power spectrum coefficients C l are quite insensitive to the effects of the Galactic magnetic field, so it is unlikely that the discordance can be reconciled by tuning the Galactic magnetic field model. On the contrary, a sizeable fraction of uniformly distributed flux (representing for instance an admixture of heavy nuclei with considerably larger deflections) can bring simulations and observations to an accord.

  16. The spectrum of high energy cosmic-ray electrons - Results and interpretation

    NASA Technical Reports Server (NTRS)

    Muller, D.; Tang, J.

    1983-01-01

    Results of a measurement of high energy cosmic-ray electrons that was performed with a balloon-borne transition radiation/shower detector telescope are presented. The data cover the energy range from 5 to 300 GeV. The interstellar spectrum below 10 GeV, which is affected by solar modulation, is derived through analysis of the nonthermal galactic radio emission, and extended to lower energies (about 300 MeV). The interstellar differential spectrum is described by a power law dependence on E with an index of -1.4 below 2 GeV, but attaining a slope of -2.6 at 2-10 GeV, and steepening further to almost -3.6 at 30-300 GeV. The features of this spectrum are interpreted in the context of galactic propagation models, assuming that the spectrum at the acceleration site has the form of a single power law. It is concluded that: (1) regions outside the galactic disk contribute to the confinement volume of electrons, (2) the containment time of electrons is of the order 10 to the 7th years and is independent of energy, (3) the spectrum at the acceleration site has a power law exponent equal to -2.65, and (4) a specific mechanism is responsible for the apparent flattening of the electron spectrum below 2 GeV.

  17. Isotropization of ultra-high energy cosmic ray arrival directions by radio ghosts

    NASA Astrophysics Data System (ADS)

    Medina-Tanco, G.; Enßlin, T. A.

    2001-10-01

    The isotropy in the ultra-high energy cosmic ray (UHECR) flux observed by Yakutsk and AGASA experiments, is a very strong constraint to production and propagation models alike. Most of the scenarios proposed in the literature should produce a sizable anisotropy as either extragalactic luminous or dark matter is normally associated with the invoked particle sources. We explore the possibility that the magnetic fields in fossil cocoons of former radio galaxies - so called radio ghosts [Enßlin, Ringberg Workshop on `Diffuse Thermal and Relativistic Plasma in Galaxy Clusters', vol. 271, MPE Report, 1999, p. 275] - are able to scatter UHECR in the intergalactic medium giving rise to the observed isotropy. We show, through numerical simulations, under which conditions this process can be operative and the magnitude of the effect. We further demonstrate, that if radio ghosts mix with the ambient medium, they might be able to produce the observed magnetic fields in clusters of galaxies. In the case of mixing, the UHECR isotropization would be even stronger than in our conservative estimates.

  18. Analysis of the mass composition of high-energy cosmic ray

    NASA Astrophysics Data System (ADS)

    Malinowski, Jan

    2013-02-01

    This paper analyses mass composition of high-energy cosmic ray, comparing simulation and experimental results. Using the nuclear interaction models QGSJET-II and Sibyll, we simulate EAS initiated by the primary nuclei representing all mass groups (p, He, O, Si, Fe). EAS is simulated for several energy levels between 1.1018 and 5.1019 eV. For such generated simulation data, we compute X-max distributions, mean X-max and RMS and compare these values with the experimental data from the Auger Experiment. The results show that for the 2-sigma confidence level, mass composition including nuclei from the CNO group and heavier can be fitted for Sibyll model only. For any combination of 3 and 4 primary particles, no model fits the experimental data at the 1-sigma confidence level. For the p + Fe bi-particle composition, or other combination of two particles, also no model fitting the experimental data can be found for the analysed energy interval.

  19. The Large Scale Structure of the Galactic Magnetic Field and High Energy Cosmic Ray Anisotropy

    NASA Astrophysics Data System (ADS)

    Alvarez-Muñiz, Jaime; Stanev, Todor

    2006-10-01

    Measurements of the magnetic field in our Galaxy are complex and usually difficult to interpret. A spiral regular field in the disk is favored by observations, however the number of field reversals is still under debate. Measurements of the parity of the field across the Galactic plane are also very difficult due to the presence of the disk field itself. In this work we demonstrate that cosmic ray protons in the energy range 1018 to 1019eV, if accelerated near the center of the Galaxy, are sensitive to the large scale structure of the Galactic Magnetic Field (GMF). In particular if the field is of even parity, and the spiral field is bi-symmetric (BSS), ultra high energy protons will predominantly come from the Southern Galactic hemisphere, and predominantly from the Northern Galactic hemisphere if the field is of even parity and axi-symmetric (ASS). There is no sensitivity to the BSS or ASS configurations if the field is of odd parity.

  20. Blazars as Ultra-high-energy Cosmic-ray Sources: Implications for TeV Gamma-Ray Observations

    NASA Astrophysics Data System (ADS)

    Murase, Kohta; Dermer, Charles D.; Takami, Hajime; Migliori, Giulia

    2012-04-01

    The spectra of BL Lac objects and Fanaroff-Riley I radio galaxies are commonly explained by the one-zone leptonic synchrotron self-Compton (SSC) model. Spectral modeling of correlated multiwavelength data gives the comoving magnetic field strength, the bulk outflow Lorentz factor, and the emission region size. Assuming the validity of the SSC model, the Hillas condition shows that only in rare cases such sources accelerate protons to much above 1019 eV, so >~ 1020 eV ultra-high-energy cosmic rays (UHECRs) are likely to be heavy ions if powered by this type of radio-loud active galactic nuclei (AGNs). Survival of nuclei is shown to be possible in TeV BL Lacs and misaligned counterparts with weak photohadronic emissions. Another signature of hadronic production is intergalactic UHECR-induced cascade emission, which is an alternative explanation of the TeV spectra of some extreme non-variable blazars such as 1ES 0229+200 or 1ES 1101-232. We study this kind of cascade signal, taking into account effects of the structured extragalactic magnetic fields in which the sources should be embedded. We demonstrate the importance of cosmic-ray deflections on the ?-ray flux, and show that required absolute cosmic-ray luminosities are larger than the average UHECR luminosity inferred from UHECR observations and can even be comparable to the Eddington luminosity of supermassive black holes. Future TeV ?-ray observations using the Cerenkov Telescope Array and the High Altitude Water Cerenkov detector array can test for UHECR acceleration by observing >25 TeV photons from relatively low redshift sources such as 1ES 0229+200, and gsimTeV photons from more distant radio-loud AGNs.

  1. BLAZARS AS ULTRA-HIGH-ENERGY COSMIC-RAY SOURCES: IMPLICATIONS FOR TeV GAMMA-RAY OBSERVATIONS

    SciTech Connect

    Murase, Kohta [Department of Physics, Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Dermer, Charles D. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Takami, Hajime [Max Planck Institute for Physics, Foehringer Ring 6, 80805 Munich (Germany); Migliori, Giulia [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2012-04-10

    The spectra of BL Lac objects and Fanaroff-Riley I radio galaxies are commonly explained by the one-zone leptonic synchrotron self-Compton (SSC) model. Spectral modeling of correlated multiwavelength data gives the comoving magnetic field strength, the bulk outflow Lorentz factor, and the emission region size. Assuming the validity of the SSC model, the Hillas condition shows that only in rare cases such sources accelerate protons to much above 10{sup 19} eV, so {approx}> 10{sup 20} eV ultra-high-energy cosmic rays (UHECRs) are likely to be heavy ions if powered by this type of radio-loud active galactic nuclei (AGNs). Survival of nuclei is shown to be possible in TeV BL Lacs and misaligned counterparts with weak photohadronic emissions. Another signature of hadronic production is intergalactic UHECR-induced cascade emission, which is an alternative explanation of the TeV spectra of some extreme non-variable blazars such as 1ES 0229+200 or 1ES 1101-232. We study this kind of cascade signal, taking into account effects of the structured extragalactic magnetic fields in which the sources should be embedded. We demonstrate the importance of cosmic-ray deflections on the {gamma}-ray flux, and show that required absolute cosmic-ray luminosities are larger than the average UHECR luminosity inferred from UHECR observations and can even be comparable to the Eddington luminosity of supermassive black holes. Future TeV {gamma}-ray observations using the Cerenkov Telescope Array and the High Altitude Water Cerenkov detector array can test for UHECR acceleration by observing >25 TeV photons from relatively low redshift sources such as 1ES 0229+200, and {approx}>TeV photons from more distant radio-loud AGNs.

  2. On the Possible Association of Ultra High Energy Cosmic Rays with Nearby Active Galaxies

    SciTech Connect

    Moskalenko, Igor V.; Stawarz, Lukasz; Porter, Troy A.; Cheung, Chi C.

    2008-05-14

    Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of cosmic rays (CRs) with energies >57 EeV that suggests a correlation with the positions of active galactic nuclei (AGN) located within {approx}75 Mpc. However, this analysis does not take into account AGN morphology. A detailed study of the sample of AGN whose positions correlate with the CR events shows that most of them are classified as Seyfert 2 and low-ionization nuclear emission-line region (LINER) galaxies which do not differ from other local AGN of the same types. Therefore, the claimed correlation between the CR events observed by the Pierre Auger Observatory and local active galaxies should be considered as resulting from a chance coincidence, if the production of the highest energy CRs is not episodic in nature, but operates in a single object on long ({ge} Myr) timescales. Additionally, most of the selected sources do not show significant jet activity, and hence--in the framework of the jet paradigm--there are no reasons for expecting them to accelerate CRs up to the highest energies, {approx}10{sup 20} eV, at all. If the extragalactic magnetic fields and the sources of these CRs are coupled with matter, it is possible that the deflection angle is larger than expected in the case of a uniform source distribution due to effectively larger fields. A future analysis has to take into account AGN morphology and may yield a correlation with a larger deflection angle and/or more distant sources. We further argue that Cen A alone could be associated with at least 4 events due to its large radio extent, and Cen B can be associated with more than 1 event due to its proximity to the Galactic plane and, correspondingly, the stronger Galactic magnetic field the ultra high energy CRs (UHECRs) encounter during propagation. If the UHECRs associated with these events are indeed accelerated by Cen A and Cen B, their deflection angles may provide information on the structure of the magnetic field in the direction of these putative sources. Future -ray observations (by, e.g., Gamma-Ray Large Area Space Telescope [GLAST], High Energy Stereoscopic System [HESS]) may provide additional clues to the nature of the accelerators of the UHECRs in the local Universe.

  3. Anisotropy expectations for ultra-high-energy cosmic rays with future high-statistics experiments

    NASA Astrophysics Data System (ADS)

    Rouillé d'Orfeuil, B.; Allard, D.; Lachaud, C.; Parizot, E.; Blaksley, C.; Nagataki, S.

    2014-07-01

    Context. Ultra-high-energy cosmic rays (UHECRs) have attracted a lot of attention in astroparticle physics and high-energy astrophysics, due to their challengingly high energies, and to their ability to constrain the physical processes and astrophysical parameters in the most energetic sources of the universe. Despite their very large acceptance, current detectors have failed to detect significant anisotropies in their arrival directions, which had been expected to lead to the long-sought identification of their sources. Some indications about the composition of the UHECRs, which may become heavier at the highest energies, have even called into question the possibility that such a goal could be achieved in the foreseeable future. Aims: We investigate the potential value of a new-generation detector, with an exposure increased by one order of magnitude, to overcome the current situation and make notable progress in detecting anisotropies and thus in the study of UHECRs. We take as an example the expected performances of the JEM-EUSO detector, assuming a uniform full-sky coverage with a total exposure of 300 000 km2 sr yr. Methods: We simulated realistic UHECR sky maps for a wide range of possible astrophysical scenarios allowed by the current constraints, taking the energy losses and photo-dissociation of the UHE protons and nuclei into account, as well as their deflections by intervening magnetic fields. These sky maps, built for both the expected statistics of JEM-EUSO and the current Pierre Auger Observatory statistics, as a reference, were analysed from the point of view of their intrinsic anisotropies, using the two-point correlation function. A statistical study of the resulting anisotropies was performed for each astrophysical scenario, varying the UHECR source composition and spectrum and the source density and exploring a set of five hundred independent realizations for each choice of a parameter set. Results: We find that significant anisotropies are expected to be detected by a next-generation UHECR detector, for essentially all the astrophysical scenarios studied, and give precise, quantitative meaning to this statement. Conclusions: Our results show that a gain of one order of magnitude in the total exposure of UHECR detectors would make a significant difference compared to the existing experiments, and would allow considerable progress in the study of these mysterious particles and their sources.

  4. Ultra High Energy Cosmic Ray Puzzle and the Plasma Wakefield Acceleration

    E-print Network

    Feng-Yin Chang; Pisin Chen; Guey-Lin Lin; Robert J. Noble; Kevin Reil; Richard Sydora

    2008-08-04

    Magnetowave induced plasma wakefield acceleration (MPWA) in a relativistic astrophysical outflow has been proposed as a viable mechanism for the acceleration of cosmic particles to ultra high energies. Here we present simulation results that demonstrate the viability of this mechanism. We invoke the high frequency and high speed whistler mode for the driving pulse. The plasma wakefield so induced validates precisely the theoretical prediction. This mechanism is shown capable of accelerating charged particles to ZeV energies in Active Galactic Nuclei (AGN).

  5. A new limit on the Ultra-High-Energy Cosmic-Ray flux with the Westerbork Synthesis Radio Telescope

    E-print Network

    S. ter Veen; S. Buitink; H. Falcke; C. W. James; M. Mevius; O. Scholten; K. Singh; B. Stappers; K. D. de Vries

    2010-10-28

    A particle cascade (shower) in a dielectric, for example as initiated by an ultra-high energy cosmic ray, will have an excess of electrons which will emit coherent \\v{C}erenkov radiation, known as the Askaryan effect. In this work we study the case in which such a particle shower occurs in a medium just below its surface. We show, for the first time, that the radiation transmitted through the surface is independent of the depth of the shower below the surface when observed from far away, apart from trivial absorption effects. As a direct application we use the recent results of the NuMoon project, where a limit on the neutrino flux for energies above $10^{22}$\\,eV was set using the Westerbork Synthesis Radio Telescope by measuring pulsed radio emission from the Moon, to set a limit on the flux of ultra-high-energy cosmic rays.

  6. Cosmic Physics: The High Energy Frontier

    E-print Network

    F. W. Stecker

    2003-09-09

    Cosmic rays have been observed up to energies $10^8$ times larger than those of the best particle accelerators. Studies of astrophysical particles (hadrons, neutrinos and photons) at their highest observed energies have implications for fundamental physics as well as astrophysics. Thus, the cosmic high energy frontier is the nexus to new particle physics. This overview discusses recent advances being made in the physics and astrophysics of cosmic rays and cosmic gamma-rays at the highest observed energies as well as the related physics and astrophysics of very high energy cosmic neutrinos. These topics touch on questions of grand unification, violation of Lorentz invariance, as well as Planck scale physics and quantum gravity.

  7. Workshop on Cosmic Ray and High Energy Gamma Ray Experiments for the Space Station Era, Louisiana State University, Baton Rouge, October 17-20, 1984, Proceedings

    NASA Technical Reports Server (NTRS)

    Jones, W. V. (editor); Wefel, J. P. (editor)

    1985-01-01

    The potential of the Space Station as a platform for cosmic-ray and high-energy gamma-ray astronomy is discussed in reviews, reports, and specific proposals. Topics examined include antiparticles and electrons, science facilities and new technology, high-energy nuclear interactions, nuclear composition and energy spectra, Space Shuttle experiments, Space Station facilities and detectors, high-energy gamma rays, and gamma-ray facilities and techniques. Consideration is given to universal-baryon-symmetry testing on the scale of galactic clusters, particle studies in a high-inclination orbit, balloon-borne emulsion-chamber results on ultrarelativistic nucleus-nucleus interactions, ionization states of low-energy cosmic rays, a large gamma-ray telescope for point-source studies above 1 GeV, and the possible existence of stable quark matter.

  8. A search for flaring very-high-energy cosmic gamma-ray sources with the L3+C muon spectrometer

    Microsoft Academic Search

    O. Adriani; M. Aguilar-Benitez; M. van den Akker; J. Alcaraz; G. Alemanni; J. Allaby; A. Aloisio; M. G. Alviggi; H. Anderhub; V. P. Andreev; F. Anselmo; A. Arefiev; T. Azemoon; T. Aziz; P. Bagnaia; A. Bajo; G. Baksay; L. Baksay; J. Bähr; S. V. Baldew; S. Banerjee; A. Barczyk; R. Barillère; P. Bartalini; M. Basile; N. Batalova; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; L. Bellucci; R. Berbeco; J. Berdugo; P. Berges; B. Bertucci; B. L. Betev; M. Biglietti; A. Biland; J. J. Blaising; S. C. Blyth; G. J. Bobbink; A. Böhm; L. Boldizsar; B. Borgia; S. Bottai; D. Bourilkov; M. Bourquin; S. Braccini; J. G. Branson; F. Brochu; J. D. Burger; W. J. Burger; X. D. Cai; M. Capell; G. Cara Romeo; G. Carlino; A. Cartacci; J. Casaus; F. Cavallari; N. Cavallo; C. Cecchi; M. Cerrada; M. Chamizo; Y. H. Chang; M. Chemarin; A. Chen; G. M. Chen; H. F. Chen; H. S. Chen; T. Chiarusi; G. Chiefari; L. Cifarelli; F. Cindolo; I. Clare; R. Clare; G. Coignet; N. Colino; S. Costantini; B. de La Cruz; S. Cucciarelli; R. de Asmundis; P. Déglon; J. Debreczeni; A. Degré; K. Dehmelt; K. Deiters; D. Della Volpe; E. Delmeire; P. Denes; F. Denotaristefani; A. de Salvo; M. Dierckxsens; L. K. Ding; C. Dionisi; M. Dittmar; A. Doria; M. T. Dova; D. Duchesneau; M. Duda; I. Duran; B. Echenard; A. Eline; A. El Hage; H. El Mamouni; A. Engler; F. J. Eppling; P. Extermann; G. Faber; M. A. Falagan; S. Falciano; A. Favara; J. Fay; O. Fedin; M. Felcini; T. Ferguson; H. Fesefeldt; E. Fiandrini; J. H. Field; F. Filthaut; P. H. Fisher; W. Fisher; I. Fisk; G. Forconi; K. Freudenreich; C. Furetta; Yu. Galaktionov; S. N. Ganguli; P. Garcia-Abia; M. Gataullin; S. Gentile; S. Giagu; Z. F. Gong; H. J. Grabosch; G. Grenier; O. Grimm; H. Groenstege; M. W. Gruenewald; M. Guida; Y. N. Guo; S. K. Gupta; V. K. Gupta; A. Gurtu; L. J. Gutay; D. Haas; Ch. Haller; D. Hatzifotiadou; Y. Hayashi; Z. X. He; T. Hebbeker; A. Hervé; J. Hirschfelder; H. Hofer; M. Hohlmann; G. Holzner; S. R. Hou; A. X. Huo; N. Ito; B. N. Jin; P. Jindal; C. L. Jing; L. W. Jones; P. de Jong; I. Josa-Mutuberría; V. Kantserov; M. Kaur; S. Kawakami; M. N. Kienzle-Focacci; J. Kirkby; W. Kittel; A. Klimentov; A. C. König; E. Kok; A. Korn; M. Kopal; V. Koutsenko; M. Kräber; H. H. Kuang; R. W. Kraemer; A. Krüger; J. Kuijpers; A. Kunin; P. Ladron de Guevara; I. Laktineh; G. Landi; M. Lebeau; A. Lebedev; P. Lecomte; P. Lecoq; P. Le Coultre; J. M. Le Goff; Y. Lei; H. Leich; R. Leiste; M. Levtchenko; P. Levtchenko; C. Li; L. Li; Z. C. Li; S. Likhoded; C. H. Lin; W. T. Lin; F. L. Linde; L. Lista; Z. A. Liu; W. Lohmann; E. Longo; Y. S. Lu; C. Luci; L. Luminari; W. Lustermann; W. G. Ma; X. H. Ma; Y. Q. Ma; L. Malgeri; A. Malinin; C. Maña; J. P. Martin; J. P. Martin; F. Marzano; K. Mazumdar; R. R. McNeil; S. Mele; X. W. Meng; L. Merola; M. Meschini; W. J. Metzger; A. van Mil; H. Milcent; G. Mirabelli; J. Mnich; G. B. Mohanty; B. Monteleoni; G. S. Muanza; A. J. M. Muijs; B. Musicar; M. Musy; S. Nagy; R. Nahnhauer; V. A. Naumov; S. Natale; M. Napolitano; F. Nessi-Tedaldi; H. Newman; A. Nisati; T. Novak; H. Nowak; R. Ofierzynski; G. Organtini; I. Pal; C. Palomares; P. Paolucci; R. Paramatti; J.-F. Parriaud; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; M. Pedace; S. Pensotti; D. Perret-Gallix; B. Petersen; D. Piccolo; F. Pierella; M. Pioppi; P. A. Piroué; E. Pistolesi; V. Plyaskin; M. Pohl; V. Pojidaev; J. Pothier; D. Prokofiev; J. Quartieri; C. R. Qing; G. Rahal-Callot; M. A. Rahaman; P. Raics; N. Raja; R. Ramelli; P. G. Rancoita; R. Ranieri; A. Raspereza; K. C. Ravindran; P. Razis; D. Ren; M. Rescigno; S. Reucroft; P. Rewiersma; S. Riemann; K. Riles; B. P. Roe; A. Rojkov; L. Romero; A. Rosca; C. Rosenbleck; S. Rosier-Lees; S. Roth; J. A. Rubio; G. Ruggiero; H. Rykaczewski; R. Saidi; A. Sakharov; S. Saremi; S. Sarkar; J. Salicio; E. Sanchez; C. Schäfer; V. Schegelsky; V. Schmitt; B. Schoeneich; H. Schopper; D. J. Schotanus; C. Sciacca; L. Servoli; C. Q. Shen; S. Shevchenko; N. Shivarov; V. Shoutko; E. Shumilov; A. Shvorob; D. Son; C. Souga; P. Spillantini; M. Steuer; D. P. Stickland; B. Stoyanov; A. Straessner; K. Sudhakar; H. Sulanke; G. Sultanov; L. Z. Sun; S. Sushkov; H. Suter; J. D. Swain; Z. Szillasi; X. W. Tang; P. Tarjan; L. Tauscher; L. Taylor; B. Tellili; D. Teyssier; C. Timmermans; Samuel C. C. Ting; S. C. Tonwar; J. Tóth; G. Trowitzsch; C. Tully; K. L. Tung; J. Ulbricht; M. Unger; E. Valente; H. Verkooijen; R. T. van de Walle; R. Vasquez; V. Veszpremi; G. Vesztergombi; I. Vetlitsky; D. Vicinanza; G. Viertel; S. Villa; M. Vivargent; S. Vlachos; I. Vodopianov; H. Vogel; H. Vogt; I. Vorobiev; A. A. Vorobyov; M. Wadhwa; R. G. Wang; Q. Wang; X. L. Wang; X. W. Wang; Z. M. Wang; M. Weber; R. van Wijk; T. A. M. Wijnen; H. Wilkens; S. Wynhoff; L. Xia; Y. P. Xu; J. S. Xu; Z. Z. Xu; B. Z. Yang; C. G. Yang; H. J. Yang; M. Yang; X. F. Yang

    2006-01-01

    The L3+C muon detector at the CERN electron positron collider, LEP, is used for the detection of very-high-energy cosmic gamma-ray sources through the observation of muons of energies above 20, 30, 50 and 100 GeV. Daily or monthly excesses in the rate of single-muon events pointing to some particular direction in the sky are searched for. The periods from mid

  9. A search for flaring very-high-energy cosmic ?-ray sources with the L3+C muon spectrometer

    Microsoft Academic Search

    P. Achard; O. Adriani; M. Aguilar-Benitez; M. van den Akker; J. Alcaraz; G. Alemanni; James V Allaby; A. Aloisio; M. G. Alviggi; H. Anderhub; V. P. Andreev; F. Anselmo; A. Arefiev; T. Azemoon; T. Aziz; P. Bagnaia; A. Bajo; G. Baksay; L. Baksay; J. Bähr; S. V. Baldew; S. Banerjee; A. Barczyk; R. Barillère; P. Bartalini; M. Basile; N. Batalova; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; L. Bellucci; R. Berbeco; J. Berdugo; P. Berges; B. Bertucci; B. L. Betev; M. Biasini; M. Biglietti; A. Biland; J. J. Blaising; S. C. Blyth; G. J. Bobbink; A. Böhm; L. Boldizsar; B. Borgia; S. Bottai; D. Bourilkov; M. Bourquin; S. Braccini; J. G. Branson; F. Brochu; J. D. Burger; W. J. Burger; X. D. Cai; M. Capell; G. Cara Romeo; G. Carlino; A. Cartacci; J. Casaus; F. Cavallari; N. Cavallo; C. Cecchi; M. Cerrada; M Chamizo-Llatas; Y. H. Chang; M. Chemarin; A. Chen; G. Chen; H. F. Chen; H. S. Chen; T. Chiarusi; G. Chiefari; L. Cifarelli; F. Cindolo; I. Clare; R. Clare; G. Coignet; N. Colino; S. Costantini; B. de la Cruz; S. Cucciarelli; R. de Asmundis; P. Déglon; J. Debreczeni; A. Degré; K. Dehmelt; K. Deiters; D. della Volpe; E. Delmeire; P. Denes; F. DeNotaristefani; A. De Salvo; M. Diemoz; M. Dierckxsens; L. K. Ding; C. Dionisi; M. Dittmar; A. Doria; M. T. Dova; D. Duchesneau; M. Duda; I. Duran; B. Echenard; A. Eline; A. El Hage; H. El Mamouni; A. Engler; F. J. Eppling; P. Extermann; G. Faber; M. A. Falagan; S. Falciano; A. Favara; J. Fay; O. Fedin; M. Felcini; T. Ferguson; H S Fesefeldt; E. Fiandrini; J. H. Field; F. Filthaut; P. H. Fisher; W. Fisher; I. Fisk; G. Forconi; K. Freudenreich; C. Furetta; Yu. Galaktionov; S. N. Ganguli; P. Garcia-Abia; M. Gataullin; S. Gentile; S. Giagu; Z. F. Gong; H. J. Grabosch; G Grabosch; O. Grimm; H. Groenstege; M. W. Gruenewald; M. Guida; Y. N. Guo; S. K. Gupta; V. K. Gupta; A. Gurtu; L. J. Gutay; D. Haas; Ch. Haller; D. Hatzifotiadou; Y. Hayashi; Z. X. He; T. Hebbeker; A. Hervé; J. Hirschfelder; H. Hofer; M. Hohlmann; G. Holzner; S. R. Hou; A. X. Huo; N. Ito; B. N. Jin; P. Jindal; C. L. Jing; L. W. Jones; P. de Jong; I. Josa-Mutuberría; V. Kantserov; M. Kaur; S. Kawakami; M. N. Kienzle-Focacci; J. K. Kim; J. Kirkby; W. Kittel; A. Klimentov; A. C. König; E. Kok; A. Korn; M. Kopal; V. Koutsenko; M. Kräber; H. H. Kuang; R. W. Kraemer; A. Krüger; J. Kuijpers; A. Kunin; P. Ladron de Guevara; I. Laktineh; G. Landi; M. Lebeau; A. Lebedev; P Lecomte; P. Lecoq; P. Le Coultre; J. M. Le Goff; Y. Lei; H. Leich; R. Leiste; M. Levtchenko; P. Levtchenko; C. Li; L. Li; Z. C. Li; S. Likhoded; C. H. Lin; W. T. Lin; F. L. Linde; L. Lista; Z. A. Liu; W. Lohmann; E. Longo; Y. S. Lu; C. Luci; L. Luminari; W. Lustermann; W. G. Ma; X. H. Ma; Y. Q. Ma; L. Malgeri; A. Malinin; C. Maña; J P Martin; J. P. Martin; F. Marzano; K. Mazumdar; R. R. McNeil; S. Mele; X. W. Meng; L. Merola; M. Meschini; W. J. Metzger; A van Mil; H. Milcent; G. Mirabelli; J. Mnich; G. B. Mohanty; B. Monteleoni; G. S. Muanza; A. J. M. Muijs; B. Musicar; M. Musy; S. Nagy; R. Nahnhauer; V. A. Naumov; S. Natale; M. Napolitano; F. Nessi-Tedaldi; H. Newman; A. Nisati; T. Novak; H. Nowak; R. Ofierzynski; G. Organtini; I. Pal; C. Palomares; P. Paolucci; R. Paramatti; J.-F. Parriaud; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; M. Pedace; S. Pensotti; D. Perret-Gallix; B. Petersen; D. Piccolo; F. Pierella; M Pioppi; P. A. Piroué; E. Pistolesi; V. Plyaskin; M. Pohl; V. Pojidaev; J. Pothier; D O Prokofiev; J. Quartieri; C. R. Qing; G. Rahal-Callot; M. A. Rahaman; P. Raics; N. Raja; R. Ramelli; P. G. Rancoita; R. Ranieri; A V Raspereza; K. C. Ravindran; P. Razis; D. Ren; M. Rescigno; S. Reucroft; P A M Rewiersma; S. Riemann; K. Riles; B. P. Roe; A. Rojkov; L. Romero; A. Rosca; C. Rosemann; C. Rosenbleck; S. Rosier-Lees; S. Roth; J. A. Rubio; G. Ruggiero; H. Rykaczewski; R. Saidi; A. Sakharov; S. Saremi; S. Sarkar; J. Salicio; E. Sanchez; C. Schäfer; V Shchegelskii; V. Schmitt; B. Schoeneich; Herwig Franz Schopper; D. J. Schotanus; C. Sciacca; L. Servoli; C. Q. Shen; S. Shevchenko; N. Shivarov; V. Shoutko; E. Shumilov; A. Shvorob; D. Son; C. Souga; P. Spillantini; M. Steuer; D. P. Stickland; B. Stoyanov; A. Straessner; K. Sudhakar; H. Sulanke; G G Sultanov; L. Z. Sun; S. Sushkov; H. Suter; J. D. Swain; Z. Szillasi; X. W. Tang; P. Tarjan; L. Tauscher; L. Taylor; B. Tellili; D. Teyssier; C. Timmermans; Samuel C. C. Ting; S. M. Ting; S. C. Tonwar; J. Tóth; G. Trowitzsch; C. Tully; K. L. Tung; J. Ulbricht; M. Unger; E. Valente; H. Verkooijen; R. T. Van de Walle; R. Vasquez; V. Veszpremi; G. Vesztergombi; I Vetlitskii; D. Vicinanza; G. Viertel; S. Villa; M. Vivargent; S. Vlachos; I. Vodopianov; H. Vogel; H. Vogt; I. Vorobiev; A. A. Vorobyov; M. Wadhwa; R. G. Wang; Q. Wang; X. L. Wang; X. W. Wang; Z. M. Wang; M. Weber; R F Van Wijk; T. A. M. Wijnen; H. Wilkens; S. Wynhoff

    2006-01-01

    The L3+C muon detector at the CERN electron–positron collider, LEP, is used for the detection of very-high-energy cosmic ?-ray sources through the observation of muons of energies above 20, 30, 50 and 100GeV. Daily or monthly excesses in the rate of single-muon events pointing to some particular direction in the sky are searched for. The periods from mid July to

  10. Detection of high energy cosmic rays with the resonant gravitational wave detector NAUTILUS and EXPLORER

    E-print Network

    P. Astone; D. Babusci; M. Bassan; P. Bonifazi; G. Cavallari; E. Coccia; S. D'Antonio; V. Fafone; G. Giordano; C. Ligi; A. Marini; G. Mazzitelli; Y. Minenkov; I. Modena; G. Modestino; A. Moleti; G. V. Pallottino; G. Pizzella; L. Quintieri; A. Rocchi; F. Ronga; R. Terenzi; M. Visco

    2008-06-14

    The cryogenic resonant gravitational wave detectors NAUTILUS and EXPLORER, made of an aluminum alloy bar, can detect cosmic ray showers. At temperatures above 1 K, when the material is in the normal conducting state, the measured signals are in good agreement with the values expected based on the cosmic rays data and on the thermo-acoustic model. When NAUTILUS was operated at the temperature of 0.14 K, in superconductive state, large signals produced by cosmic ray interactions, more energetic than expected, were recorded. The NAUTILUS data in this case are in agreement with the measurements done by a dedicated experiment on a particle beam. The biggest recorded event was in EXPLORER and excited the first longitudinal mode to a vibrational energy of about 670 K, corresponding to about 360 TeV absorbed in the bar. Cosmic rays can be an important background in future acoustic detectors of improved sensitivity. At present, they represent a useful tool to verify the gravitational wave antenna performance.

  11. Cosmic ray composition at high energies: Results from the TRACER project

    E-print Network

    P. J. Boyle; M. Ave; F. Gahbauer; C. Hoeppner; J. Hoerandel; M. Ichimura; D. Mueller; A. Romero-Wolf

    2007-03-28

    The TRACER instrument Transition Radiation Array for Cosmic Energetic Radiation is designed to measure the individual energy spectra of cosmic-ray nuclei in long-duration balloon flights The large geometric factor of TRACER 5 m 2 sr permits statistically significant measurements at particle energies well beyond 10 14 eV TRACER identifies individual cosmic-ray nuclei with single-element resolution and measures their energy over a very wide range from about 0 5 to 10 000 GeV nucleon This is accomplished with a gas detector system of 1600 single-wire proportional tubes and plastic fiber radiators that measure specific ionization and transition radiation signals combined with plastic scintillators and acrylic Cherenkov counters A two-week flight in Antarctica in December 2003 has led to a measurement of the nuclear species oxygen to iron O Ne Mg Si S Ar Ca and Fe up to about 3 000 GeV nucleon We shall present the energy spectra and relative abundances for these elements and discuss the implication of the results in the context of current models of acceleration and propagation of galactic cosmic rays The instrument has been refurbished for a second long-duration flight in the Northern hemisphere scheduled for summer 2006 For this flight the dynamic range of TRACER has been extended to permit inclusion of the lighter elements B C and N in the measurement.

  12. Model-dependent Estimate on the Connection between Fast Radio Bursts and Ultra High Energy Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Zhou, Bei; He, Hao-Ning; Fan, Yi-Zhong; Wei, Da-Ming

    2014-12-01

    The existence of fast radio bursts (FRBs), a new type of extragalatic transient, has recently been established, and quite a few models have been proposed. In this work, we discuss the possible connection between the FRB sources and ultra high energy (>1018 eV) cosmic rays. We show that in the blitzar model and the model of merging binary neutron stars, which includes the huge energy release of each FRB central engine together with the rather high rate of FRBs, the accelerated EeV cosmic rays may contribute significantly to the observed ones. In other FRB models, including, for example, the merger of double white dwarfs and the energetic magnetar radio flares, no significant EeV cosmic ray is expected. We also suggest that the mergers of double neutron stars, even if they are irrelevant to FRBs, may play a nonignorable role in producing EeV cosmic ray protons if supramassive neutron stars are formed in a sufficient fraction of mergers and the merger rate is >~ 103 yr-1 Gpc-3. Such a possibility will be unambiguously tested in the era of gravitational wave astronomy.

  13. Energy and Flux Measurements of Ultra-High Energy Cosmic Rays Observed During the First ANITA Flight

    E-print Network

    Schoorlemmer, H; Romero-Wolf, A; García-Fernández, D; Bugaev, V; Wissel, S A; Allison, P; Alvarez-Muñiz, J; Barwick, S W; Beatty, J J; Besson, D Z; Binns, W R; Carvalho, W R; Chen, C; Chen, P; Clem, J M; Connolly, A; Dowkontt, P F; DuVernois, M A; Field, R C; Goldstein, D; Gorham, P W; Hast, C; Heber, C L; Huege, T; Hoover, S; Israel, M H; Javaid, A; Kowalski, J; Lam, J; Learned, J G; Liewer, K M; Link, J T; Lusczek, E; Matsuno, S; Mercurio, B C; Miki, C; Mio?inovi?, P; Mulrey, K; Nam, J; Naudet, C J; Ng, J; Nichol, R J; Palladino, K; Rauch, B F; Roberts, J; Reil, K; Rotter, B; Rosen, M; Ruckman, L; Saltzberg, D; Seckel, D; Urdaneta, D; Varner, G S; Vieregg, A G; Walz, D; Wu, F; Zas, E

    2015-01-01

    The first flight of the Antarctic Impulsive Transient Antenna (ANITA) experiment recorded 16 radio signals that were emitted by cosmic-ray induced air showers. For 14 of these events, this radiation was reflected from the ice. The dominant contribution to the radiation from the deflection of positrons and electrons in the geomagnetic field, which is beamed in the direction of motion of the air shower. This radiation is reflected from the ice and subsequently detected by the ANITA experiment at a flight altitude of 36km. In this paper, we estimate the energy of the 14 individual events and find that the mean energy of the cosmic-ray sample is 2.9 EeV. By simulating the ANITA flight, we calculate its exposure for ultra-high energy cosmic rays. We estimate for the first time the cosmic-ray flux derived only from radio observations. In addition, we find that the Monte Carlo simulation of the ANITA data set is in agreement with the total number of observed events and with the properties of those events.

  14. Implementing the De-thinning Method for High Energy Cosmic Rays Extensive Air Shower Simulations

    E-print Network

    Estupiñán, A; Núñez, L A

    2015-01-01

    To simulate the interaction of cosmic rays with the Earth atmosphere requires highly complex computational resources and several statistical techniques have been developed to simplify those calculations. It is common to implement the thinning algorithms to reduce the number of secondary particles by assigning weights to representative particles in the evolution of the cascade. However, since this is a compression method with information loss, it is required to recover the original flux of secondary particles without introduce artificial biases. In this work we present the preliminary results of our version of the de-thinning algorithm for the reconstruction of thinned simulations of extensive air showers initiated by cosmic rays and photons in the energy range $10^{15} < E/\\mathrm{eV} < 10^{17}$.

  15. Gradients and anisotropies of high energy cosmic rays in the outer heliosphere

    NASA Technical Reports Server (NTRS)

    Fillius, W.; Roelof, E. C.; Smith, E. J.; Wood, D.; Ip, W. H.

    1985-01-01

    Two cosmic rays which pass through the same point going in opposite directions will, in the absence of scattering and inhomogeneities in the magnetic field, trace helices about adjacent flux tubes, whose centerlines are separated by one gyrodiameter. A directional anisotropy at the point suggests a difference in the number of cosmic rays loading the two flux tubes; that is, a density gradient over the baseline of a gyrodiameter. Previous studies at lower energies have shown that the cosmic ray density gradients vary in time and space. It is suggested that the radial gradient associated with solar cycle modulation is supported largely by narrow barriers which encircle the sun and propagate outward with the solar wind. If so, the anisotropy is a desirable way to detect spatial gradients, because it can be associated with the local solar wind and magnetic field conditions. Anisotropic measurements made by Cerenkov detectors on Pioneers 10 and 11 were studied. It was found that local anisotropy varies greatly, but that the long term average is consistent with the global radial gradient measured between two spacecraft over a baseline of many AU.

  16. A Study of the Composition of Ultra High Energy Cosmic Rays using the High Resolution Fly's Eye

    NASA Astrophysics Data System (ADS)

    Archbold, Greg

    2003-04-01

    The composition of Ultra High Energy Cosmic Rays (UHECR) was studied with the High Resolution Fly's Eye cosmic ray observatory (HiRes) located on the U.S. Army's Dugway Proving Ground in the West Desert of Utah. The QGSJet01 and SIBYLL 2.1 hadronic interaction models were used in versions 6.005 and 6.010 of the CORSIKA event generator to study predicted elongation rates and X_max distribution widths in the UHECR regime. The CORSIKA-generated EAS were incorporated directly into a detailed atmospheric and detector Monte Carlo. The data were reconstructed using measurements of the atmosphere, well-determined geometry, a global profile fit, and a detailed atmospheric and detector Monte Carlo. Elongation rate and X_max distribution results will be shown for data collected in stereo between November 1999 and September 2001.

  17. The energy spectrum of ultra high energy cosmic rays measured by the High Resolution Fly's Eye detectors

    NASA Astrophysics Data System (ADS)

    Reil, Kevin Alexander

    This dissertation will present the energy spectrum of Ultra High Energy Cosmic Rays (UHECR) above 1018eV (1 EeV). The measurement is made using data from the stereo High Resolution Fly's Eye Cosmic Ray Observatory (HiRes). Data using both an average atmospheric calibration and preliminary hourly atmospheric corrections are presented. To carry out this study, a full stereo Monte Carlo with direct CORSIKA input, the Dugway atmosphere and the HiRes optics and electronics has been developed. An intrinsic energy resolution of less than 10% over all energies discussed will be shown. The measured spectrum is significantly lower than both the Fly's Eye stereo and AGASA measurements [1, 2]. However, the measurement is within error of the Fly's Eye measurement when including systematic atmospheric uncertainty. A systematic shift in energy scale of 40% is required to bring this measurement into agreement with AGASA.

  18. Propagation of ultra-high-energy cosmic ray nuclei in cosmic magnetic fields and implications for anisotropy measurements

    NASA Astrophysics Data System (ADS)

    Takami, Hajime; Inoue, Susumu; Yamamoto, Tokonatsu

    2012-07-01

    Recent results from the Pierre Auger Observatory (PAO) indicate that the composition of ultra-high-energy cosmic rays (UHECRs) with energies above 1019 eV may be dominated by heavy nuclei. An important question is whether the distribution of arrival directions for such UHECR nuclei can exhibit observable anisotropy or positional correlations with their astrophysical source objects despite the expected strong deflections by intervening magnetic fields. For this purpose, we have simulated the propagation of UHECR nuclei including models for both the extragalactic magnetic field (EGMF) and the Galactic magnetic field (GMF). We find that the GMF is particularly crucial for suppressing the anisotropy as well as source correlations. Assuming that only iron nuclei are injected steadily from sources with equal luminosity and spatially distributed according to the observed large scale structure in the local Universe, at the number of events published by the PAO so far (69 events above 5.5 × 1019 eV), the arrival distribution of UHECRs would be consistent with no auto-correlation at 95% confidence if the mean number density of UHECR sources ns ? 10-6 Mpc-3, and consistent with no cross-correlation with sources within 95% errors for ns ? 10-5 Mpc-3. On the other hand, with 1000 events above 5.5 × 1019 eV in the whole sky, next generation experiments can reveal auto-correlation with more than 99% probability even for ns ? 10-3 Mpc-3, and cross-correlation with sources with more than 99% probability for ns ? 10-4 Mpc-3. In addition, we find that the contribution of Centaurus A is required to reproduce the currently observed UHECR excess in the Centaurus region. Secondary protons generated by photodisintegration of primary heavy nuclei during propagation play a crucial role in all cases, and the resulting anisotropy at small angular scales should provide a strong hint of the source location if the maximum energies of the heavy nuclei are sufficiently high.

  19. Cosmic Rays

    NSDL National Science Digital Library

    Mendez, J.

    This series of web pages, authored and curated by David P. Stern, gives an elementary discussion of cosmic rays, followed by sections on high energy particles in the universe and high-energy particles from the Sun. It describes the existence particles whose velocity approaches that of light, their probable sources, and their measurement. This is part of a large work, "The Exploration of the Earth's Magnetosphere", that gives a non-mathematical introduction to planetary and solar magnetic fields, space weather, aurora, and charged particle motion. A Spanish translation is available.

  20. Magnetowave Induced Plasma Wakefield Acceleration for Ultra High Energy Cosmic Rays

    SciTech Connect

    Chang, Feng-Yin; /Taiwan, Natl. Chiao Tung U. /Taiwan, Natl. Taiwan U.; Chen, Pisin; /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC; Lin, Guey-Lin; /Taiwan, Natl. Chiao Tung U. /Taiwan, Natl. Taiwan U.; Noble, Robert; /SLAC; Sydora, Richard; /Alberta U.

    2009-10-17

    Magnetowave induced plasma wakefield acceleration (MPWA) in a relativistic astrophysical outflow has been proposed as a viable mechanism for the acceleration of cosmic particles to ultrahigh energies. Here we present simulation results that clearly demonstrate the viability of this mechanism for the first time. We invoke the high frequency and high speed whistler mode for the driving pulse. The plasma wakefield obtained in the simulations compares favorably with our newly developed relativistic theory of the MPWA. We show that, under appropriate conditions, the plasma wakefield maintains very high coherence and can sustain high-gradient acceleration over hundreds of plasma skin depths. Invoking active galactic nuclei as the site, we show that MPWA production of ultrahigh energy cosmic rays beyond ZeV (10{sup 21} eV) is possible.

  1. Fermi LAT Results and Perspectives in Measurements of High Energy Galactic Cosmic Rays

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander

    2010-01-01

    Real breakthrough during last 1-1.5 years in cosmic ray electrons: ATIC, HESS, Pamela, and finally Fermi-LAT. New quality data have made it possible to start quantitative modeling. With the new data more puzzles than before on CR electrons origin. Need "multi-messenger" campaign: electrons, positrons, gammas, X-ray, radio, neutrino... It is viable that we are dealing with at least two distinct mechanisms of "primary" electron (both signs) production: a softer spectrum of negative electrons, and a harder spectrum of both e(+)+e(-). Exotic (e.g. DM) origin is not ruled out. Upper limits on CR electrons anisotropy are set. Good perspectives to have the Fermi LAT results on proton spectrum and positron fraction.

  2. Engine-driven Relativistic Supernovae as Sources of Ultra High Energy Cosmic Rays

    E-print Network

    Ray, Alak

    2011-01-01

    Understanding the origin of the highest energy cosmic rays is a crucial step in probing new physics at energies unattainable by terrestrial accelerators. Their sources remain an enigma half a century after their discovery. They must be accelerated in the local universe as otherwise interaction with cosmic background radiations would severely deplete the flux of protons and nuclei at energies above the Greisen-Zatsepin-Kuzmin (GZK) limit. Hypernovae, nearby GRBs, AGNs and their flares have all been suggested and debated in the literature as possible sources. Type Ibc supernovae have a local sub-population with mildly relativistic ejecta which are known to be sub-energetic GRBs or X-Ray Flashes for sometime and more recently as those with radio afterglows but without detected GRB counterparts, such as SN 2009bb. In this work we measure the size-magnetic field evolution, baryon loading and energetics of SN 2009bb using its radio spectra obtained with VLA and GMRT. We show that the engine-driven SNe lie above the...

  3. PeV neutrinos from the propagation of ultra-high energy cosmic rays

    NASA Astrophysics Data System (ADS)

    Roulet, Esteban; Sigl, Guenter; van Vliet, Arjen; Mollerach, Silvia

    2013-01-01

    We discuss the possibility that the PeV neutrinos recently observed by IceCube are produced by the interactions of extragalactic cosmic rays during their propagation through the radiation backgrounds. We show that the fluxes resulting from the decays of neutrons produced in the interactions of cosmic ray protons with the CMB background are suppressed (E?2d??/dE < 10-10 GeV/cm2 s sr), with those resulting from the decays of pions produced in the interactions with the UV/optical/IR backgrounds being the dominant ones at PeV energies. The anti-neutrino fluxes produced by the decay of neutrons resulting from the photodisintegration of heavy nuclei with CMB photons are also shown to be quite suppressed (E?2d??/dE < 10-11 GeV/cm2 s sr), while those produced by photo-pion processes with UV/optical/IR backgrounds may be larger, although they are not expected to be above those achievable in the pure proton case. Scenarios with mixed composition and low cutoff rigidities can lead to PeV neutrino fluxes enhanced with respect to those in the pure Fe scenarios. We also discuss the possible impact of the Glashow resonance for the detection of these scenarios, showing that it plays a moderate role.

  4. Probing the origin of cosmic rays with extremely high energy neutrinos using the IceCube Observatory

    NASA Astrophysics Data System (ADS)

    Aartsen, M. G.; Abbasi, R.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Altmann, D.; Arguelles, C.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Baum, V.; Bay, R.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; BenZvi, S.; Berghaus, P.; Berley, D.; Bernardini, E.; Bernhard, A.; Besson, D. Z.; Binder, G.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Bose, D.; Böser, S.; Botner, O.; Brayeur, L.; Bretz, H.-P.; Brown, A. M.; Bruijn, R.; Casey, J.; Casier, M.; Chirkin, D.; Christov, A.; Christy, B.; Clark, K.; Clevermann, F.; Coenders, S.; Cohen, S.; Cowen, D. F.; Cruz Silva, A. H.; Danninger, M.; Daughhetee, J.; Davis, J. C.; Day, M.; De Clercq, C.; De Ridder, S.; Desiati, P.; de Vries, K. D.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; Dunkman, M.; Eagan, R.; Eberhardt, B.; Eisch, J.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Fedynitch, A.; Feintzeig, J.; Feusels, T.; Filimonov, K.; Finley, C.; Fischer-Wasels, T.; Flis, S.; Franckowiak, A.; Frantzen, K.; Fuchs, T.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Gladstone, L.; Glüsenkamp, T.; Goldschmidt, A.; Golup, G.; Gonzalez, J. G.; Goodman, J. A.; Góra, D.; Grandmont, D. T.; Grant, D.; Gretskov, P.; Groh, J. C.; Groß, A.; Ha, C.; Haj Ismail, A.; Hallen, P.; Hallgren, A.; Halzen, F.; Hanson, K.; Heereman, D.; Heinen, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Homeier, A.; Hoshina, K.; Huelsnitz, W.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Ishihara, A.; Jacobi, E.; Jacobsen, J.; Jagielski, K.; Japaridze, G. S.; Jero, K.; Jlelati, O.; Kaminsky, B.; Kappes, A.; Karg, T.; Karle, A.; Kauer, M.; Kelley, J. L.; Kiryluk, J.; Kläs, J.; Klein, S. R.; Köhne, J.-H.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kopper, C.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Krasberg, M.; Kriesten, A.; Krings, K.; Kroll, G.; Kunnen, J.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Landsman, H.; Larson, M. J.; Lesiak-Bzdak, M.; Leuermann, M.; Leute, J.; Lünemann, J.; Macías, O.; Madsen, J.; Maggi, G.; Maruyama, R.; Mase, K.; Matis, H. S.; McNally, F.; Meagher, K.; Merck, M.; Meures, T.; Miarecki, S.; Middell, E.; Milke, N.; Miller, J.; Mohrmann, L.; Montaruli, T.; Morse, R.; Nahnhauer, R.; Naumann, U.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke, A.; Odrowski, S.; Olivas, A.; Omairat, A.; O'Murchadha, A.; Paul, L.; Pepper, J. A.; Pérez de los Heros, C.; Pfendner, C.; Pieloth, D.; Pinat, E.; Posselt, J.; Price, P. B.; Przybylski, G. T.; Rädel, L.; Rameez, M.; Rawlins, K.; Redl, P.; Reimann, R.; Resconi, E.; Rhode, W.; Ribordy, M.; Richman, M.; Riedel, B.; Rodrigues, J. P.; Rott, C.; Ruhe, T.; Ruzybayev, B.; Ryckbosch, D.; Saba, S. M.; Sander, H.-G.; Santander, M.; Sarkar, S.; Schatto, K.; Scheriau, F.; Schmidt, T.; Schmitz, M.; Schoenen, S.; Schöneberg, S.; Schönwald, A.; Schukraft, A.; Schulte, L.; Schulz, O.; Seckel, D.; Sestayo, Y.; Seunarine, S.; Shanidze, R.; Sheremata, C.; Smith, M. W. E.; Soldin, D.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stanisha, N. A.; Stasik, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strahler, E. A.; Ström, R.; Sullivan, G. W.; Taavola, H.; Taboada, I.; Tamburro, A.; Tepe, A.; Ter-Antonyan, S.; Teši?, G.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Toscano, S.; Unger, E.; Usner, M.; Vallecorsa, S.; van Eijndhoven, N.; Van Overloop, A.; van Santen, J.; Vehring, M.; Voge, M.; Vraeghe, M.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Weaver, Ch.; Wellons, M.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Williams, D. R.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; Ziemann, J.; Zierke, S.; Zoll, M.

    2013-12-01

    We have searched for extremely high energy neutrinos using data taken with the IceCube detector between May 2010 and May 2012. Two neutrino-induced particle shower events with energies around 1 PeV were observed, as reported previously. In this work, we investigate whether these events could originate from cosmogenic neutrinos produced in the interactions of ultrahigh energy cosmic rays with ambient photons while propagating through intergalactic space. Exploiting IceCube’s large exposure for extremely high energy neutrinos and the lack of observed events above 100 PeV, we can rule out the corresponding models at more than 90% confidence level. The model-independent quasidifferential 90% C.L. upper limit, which amounts to E2??e+??+??=1.2×10-7GeVcm-2s-1sr-1 at 1 EeV, provides the most stringent constraint in the energy range from 10 PeV to 10 EeV. Our observation disfavors strong cosmological evolution of the highest energy cosmic-ray sources such as the Fanaroff-Riley type II class of radio galaxies.

  5. A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahlers, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antici'c, T.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Badescu, A. M.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Bäuml, J.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Bohácová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brancus, I.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caccianiga, B.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Cheng, S. H.; Chiavassa, A.; Chinellato, J. A.; Chirinos Diaz, J.; Chudoba, J.; Cilmo, M.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; del Peral, L.; del Río, M.; Deligny, O.; Dembinski, H.; Dhital, N.; Di Giulio, C.; Díaz Castro, M. L.; Diep, P. N.; Diogo, F.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Facal San Luis, P.; Fajardo Tapia, I.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Fick, B.; Filevich, A.; Filipcic, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fratu, O.; Fröhlich, U.; Fuchs, B.; Gaior, R.; Gamarra, R. F.; Gambetta, S.; García, B.; Garcia Roca, S. T.; Garcia-Gamez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gómez Vitale, P. F.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Gorgi, A.; Gouffon, P.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Guzman, A.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harrison, T. A.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Hollon, N.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Horvath, P.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jarne, C.; Jiraskova, S.; Josebachuili, M.; Kadija, K.; Kampert, K. H.; Karhan, P.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lauer, R.; Lautridou, P.; Le Coz, S.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lu, L.; Lucero, A.; Ludwig, M.; Lyberis, H.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, J.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martinez, H.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurel, D.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mi'canovi'c, S.; Micheletti, M. I.; Minaya, I. A.; Miramonti, L.; Molina-Bueno, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Mostafá, M.; Moura, C. A.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Nhung, P. T.; Niechciol, M.; Niemietz, L.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Pastor, S.; Paul, T.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.

    2012-04-01

    Observations of cosmic ray arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Véron-Cetty Véron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three methods can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. Using data taken from January 1, 2004 to July 31, 2010 we examined the 20,30,...,110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays.

  6. A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory

    SciTech Connect

    Abreu, P.; ,

    2012-01-01

    Observations of cosmic ray arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three methods can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. Using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ..., 110 highest energy events with a corresponding minimum energy threshold of about 51 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays.

  7. A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory

    SciTech Connect

    Abreu, P.; Andringa, S. [LIP and Instituto Superior Técnico, Technical University of Lisbon (Portugal); Aglietta, M. [Istituto di Fisica dello Spazio Interplanetario (INAF), Università di Torino and Sezione INFN, Torino (Italy); Ahlers, M. [University of Wisconsin, Madison, WI (United States); Ahn, E.J. [Fermilab, Batavia, IL (United States); Albuquerque, I.F.M. [Universidade de São Paulo, Instituto de Física, São Paulo, SP (Brazil); Allard, D. [Laboratoire AstroParticule et Cosmologie (APC), Université Paris 7, CNRS-IN2P3, Paris (France); Allekotte, I. [Centro Atómico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), San Carlos de Bariloche (Argentina); Allen, J. [New York University, New York, NY (United States); Allison, P. [Ohio State University, Columbus, OH (United States); Almela, A. [Universidad Tecnológica Nacional - Facultad Regional Buenos Aires, Buenos Aires (Argentina); Castillo, J. Alvarez [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico); Alvarez-Muñiz, J. [Universidad de Santiago de Compostela (Spain); Ambrosio, M.; Aramo, C. [Università di Napoli 'Federico II' and Sezione INFN, Napoli (Italy); Aminaei, A. [IMAPP, Radboud University Nijmegen (Netherlands); Anchordoqui, L. [University of Wisconsin, Milwaukee, WI (United States); Antici'c, T. [Rudjer Boškovi'c Institute, 10000 Zagreb (Croatia); Arganda, E. [IFLP, Universidad Nacional de La Plata and CONICET, La Plata (Argentina); Arqueros, F., E-mail: auger_spokesperson@fnal.gov [Universidad Complutense de Madrid, Madrid (Spain); Collaboration: Pierre Auger Collaboration; and others

    2012-04-01

    Observations of cosmic ray arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Véron-Cetty Véron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt–L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three methods can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. Using data taken from January 1, 2004 to July 31, 2010 we examined the 20,30,...,110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays.

  8. Ultra High Energy Cosmic Ray Acceleration in Engine-driven Relativistic Supernovae

    E-print Network

    Chakraborti, Sayan; Soderberg, Alicia; Loeb, Abraham; Chandra, Poonam

    2010-01-01

    The origin of the highest energy cosmic rays remains an enigma. They offer a window to new physics, including tests of physical laws relevant to their propagation and interactions, at energies unattainable by terrestrial accelerators. They must be accelerated locally, as otherwise background radiations would severely suppress the flux of protons and nuclei, at energies above the Greisen-Zatsepin-Kuzmin (GZK) limit. Nearby Gamma Ray Bursts (GRBs), Hypernovae, Active Galactic Nuclei (AGNs) and their flares, have all been suggested and debated as possible sources. A local sub-population of type Ibc supernovae (SNe) with mildly relativistic outflows have been detected as sub-energetic GRBs or X-Ray Flashes (XRFs) and recently as radio afterglows without detected GRB counterparts. We measure the size-magnetic field evolution, baryon loading and energetics, using the observed radio spectra of SN 2009bb. We place such engine-driven SNe above the Hillas line and establish that they can readily explain the post-GZK UH...

  9. High-energy Cosmic Rays and Neutrinos from Semi-relativistic Hypernovae

    E-print Network

    Xiang-Yu Wang; Soebur Razzaque; Peter Meszaros; Zi-Gao Dai

    2007-09-12

    The origin of the ultrahigh-energy (UHE) cosmic rays (CRs) from the second knee ($\\sim6\\times10^{17}$eV) above in the CR spectrum is still unknown. Recently, there has been growing evidence that a peculiar type of supernovae, called hypernovae, are associated with sub-energetic gamma-ray bursts (GRBs), such as SN1998bw/GRB980425 and SN2003lw/GRB031203. Such hypernovae appear to have high (up to mildly relativistic) velocity ejecta, which may be linked to the sub-energetic GRBs. Assuming a continuous distribution of the kinetic energy of the hypernova ejecta as a function of its velocity $E_k\\propto (\\Gamma\\beta)^{-\\alpha}$ with $\\alpha\\sim 2$, we find that 1) the external shock wave produced by the high velocity ejecta of a hypernova can accelerate protons up to energies as high as $10^{19} {\\rm eV}$; 2) the cosmological hypernova rate is sufficient to account for the energy flux above the second knee; and 3) the steeper spectrum of CRs at these energies can arise in these sources. In addition, hypernovae would also give rise to a faint diffuse UHE neutrino flux, due to $p\\gamma$ interactions of the UHE CRs with hypernova optical-UV photons.

  10. Can multistate dark matter annihilation explain the high-energy cosmic ray lepton anomalies?

    NASA Astrophysics Data System (ADS)

    Cirelli, Marco; Cline, James M.

    2010-07-01

    Multistate dark matter (DM) models with small mass splittings and couplings to light hidden sector bosons have been proposed as an explanation for the PAMELA/Fermi/H.E.S.S. high-energy lepton excesses. We investigate this proposal over a wide range of DM density profiles, in the framework of concrete models with doublet or triplet dark matter and a hidden SU(2) gauge sector that mixes with standard model hypercharge. The gauge coupling is bounded from below by the DM relic density, and the Sommerfeld enhancement factor is explicitly computable for given values of the DM and gauge boson masses M, ? and the (largest) dark matter mass splitting ?M12. Sommerfeld enhancement is stronger at the galactic center than near the Sun because of the radial dependence of the DM velocity profile, which strengthens the inverse Compton (IC) gamma ray constraints relative to usual assumptions. We find that the PAMELA/Fermi/H.E.S.S. lepton excesses are marginally compatible with the model predictions, and with CMB and Fermi gamma ray constraints, for M?800GeV, ??200MeV, and a dark matter profile with noncuspy Einasto parameters ??0.20, rs˜30kpc. We also find that the annihilating DM must provide only a subdominant (?0.4) component of the total DM mass density, since otherwise the boost factor due to Sommerfeld enhancement is too large.

  11. Can multistate dark matter annihilation explain the high-energy cosmic ray lepton anomalies?

    E-print Network

    Marco Cirelli; James M. Cline

    2010-05-22

    Multistate dark matter (DM) models with small mass splittings and couplings to light hidden sector bosons have been proposed as an explanation for the PAMELA/Fermi/H.E.S.S. high-energy lepton excesses. We investigate this proposal over a wide range of DM density profiles, in the framework of concrete models with doublet or triplet dark matter and a hidden SU(2) gauge sector that mixes with standard model hypercharge. The gauge coupling is bounded from below by the DM relic density, and the Sommerfeld enhancement factor is explicitly computable for given values of the DM and gauge boson masses M, mu and the (largest) dark matter mass splitting delta M_{12}. Sommerfeld enhancement is stronger at the galactic center than near the Sun because of the radial dependence of the DM velocity profile, which strengthens the inverse Compton (IC) gamma ray constraints relative to usual assumptions. We find that the PAMELA/Fermi/H.E.S.S. lepton excesses are marginally compatible with the model predictions, and with CMB and Fermi gamma ray constraints, for M ~ 800 GeV, mu ~ 200 MeV, and a dark matter profile with noncuspy Einasto parameters alpha > 0.20, r_s ~ 30 kpc. We also find that the annihilating DM must provide only a subdominant (component of the total DM mass density, since otherwise the boost factor due to Sommerfeld enhancement is too large.

  12. High Energy Gamma Rays

    E-print Network

    R. Mukherjee

    2000-09-22

    This article reviews the present status of high energy gamma-ray astronomy at energies above 30 MeV. Observations in the past decade using both space- and ground-based experiments have been primarily responsible for giving a tremendous boost to our knowledge of the high energy Universe. High energy gamma-rays have been detected from a wide range of Galactic and extragalactic astrophysical sources, such as gamma-ray bursters, pulsars, and active galaxies. These observations have established high energy gamma-ray astronomy as a vital and exciting field, that has a bright future. This review summarizes the experimental techniques, observations and results obtained with recent experiments, and concludes with a short description of future prospects.

  13. Radio detection of high-energy cosmic rays at the Pierre Auger Observatory

    SciTech Connect

    Berg, A.M.van den; Collaboration, for the Pierre Auger

    2007-08-01

    The southern Auger Observatory provides an excellent test bed to study the radio detection of extensive air showers as an alternative, cost-effective, and accurate tool for cosmic-ray physics. The data from the radio setup can be correlated with those from the well-calibrated baseline detectors of the Pierre Auger Observatory. Furthermore, human-induced radio noise levels at the southern Auger site are relatively low. We have started an R&D program to test various radio-detection concepts. Our studies will reveal Radio Frequency Interferences (RFI) caused by natural effects such as day-night variations, thunderstorms, and by human-made disturbances. These RFI studies are conducted to optimize detection parameters such as antenna design, frequency interval, antenna spacing and signal processing. The data from our initial setups, which presently consist of typically 3 - 4 antennas, will be used to characterize the shower from radio signals and to optimize the initial concepts. Furthermore, the operation of a large detection array requires autonomous detector stations. The current design is aiming at stations with antennas for two polarizations, solar power, wireless communication, and local trigger logic. The results of this initial phase will provide an important stepping stone for the design of a few tens kilometers square engineering array.

  14. On Gamma Ray Burst and Blazar AGN Origins of the Ultra-High Energy Cosmic Rays in Light of First Results from Auger

    E-print Network

    Charles D. Dermer

    2007-12-14

    The discoveries of the GZK cutoff with the HiRes and Auger Observatories and the discovery by Auger of clustering of >~60 EeV ultra-high energy cosmic rays (UHECRs) towards nearby <~75 Mpc) AGNs along the supergalactic plane establishes the astrophysical origin of the UHECRs. The likely sources of the UHECRs are gamma-ray bursts and radio-loud AGNs because: (1) they are extragalactic; (2) they are sufficiently powerful; (3) acceleration to ultra-high energies can be achieved in their relativistic ejecta; (4) anomalous X-ray and gamma-ray features can be explained by nonthermal hadron acceleration in relativistic blast waves; and (5) sources reside within the GZK radius. Two arguments for acceleration to UHE are presented, and limits on UHECR ion acceleration are set. UHECR ions are shown to be able to survive without photodisintegrating while passing through the AGN scattered radiation field, even if launched deep in the broad line region. UHECR injection throughout cosmic time fits the measured energy spectrum of UHECRs, at least for protons. Local UHECR proton and ion interaction and energy-loss mean free paths are calculated using an empirical fit to the extragalactic background light (EBL) at IR and optical energies. Minimum intergalactic magnetic (IGM) fields ~1e-11 G are derived from clustering assuming specific source origins, e.g., Cen A, nearby AGNs, or GRBs for the super-GZK CRs seen with Auger. Besides distinct cosmic-ray induced gamma-ray signatures that should be observed with the Gamma ray Large Area Space Telescope (GLAST), source and GZK neutrino detections and the arrival distribution of UHECR in direction and time can finally decide the sources of cosmic rays at the highest energies.

  15. Germ cell mutagenesis in medaka fish after exposures to high-energy cosmic ray nuclei: A human model

    NASA Astrophysics Data System (ADS)

    Shimada, Atsuko; Shima, Akihiro; Nojima, Kumie; Seino, Yo; Setlow, Richard B.

    2005-04-01

    Astronauts beyond the Earth's orbit are exposed to high-energy cosmic-ray nuclei with high values of linear energy transfer (LET), resulting in much more biological damage than from x-rays or -rays and may result in mutations and cancer induction. The relative biological effectiveness of these nuclei depends on the LET, rising to as high as 50 at LET values of 100-200 keV/µm. An endpoint of concern is germ cell mutations passed on to offspring, arising from exposure to these nuclei. A vertebrate model for germ cell mutation is Medaka fish (Oryzias latipes). We exposed wild type males to doses of 1 GeV per nucleon Fe nuclei or to 290 MeV per nucleon C nuclei. They were mated to females with recessive mutations at five-color loci. The transparent embryos from >100 days of mating (representing exposed sperm, spermatids, or spermatogonia) were observed so as to detect dominant lethal mutations and total color mutations, even though the embryos might not hatch. The relative number of mutant embryos as a function of dose were compared with those induced by -rays. The relative biological effectiveness values for dominant lethal mutations and total color mutations for exposed sperm and spermatids were 1.3-2.1 for exposure to C nuclei and 1.5-3.0 for exposure to Fe nuclei. (The spermatogonial data were uncertain.) These low values, and the negligible number of viable mutations, compared with those for mutations in somatic cells and for neoplastic transformation, indicate that germ cell mutations arising from exposures to cosmic ray nuclei are not a significant hazard to astronauts. astronaut hazards | linear energy transfer | relative biological effect

  16. The Dynamics of High-energy Cosmic Rays In Near Earth Space and Earthquake Prediction

    Microsoft Academic Search

    S. Alexandrin; A. Galper; L. Grishantseva; S. Koldashov; L. Maslennikov; A. Murashov; P. Picozza; S. Voronov

    2002-01-01

    The existence of correlation between short-term variations of high energy charged par- ticle fluxes in the near Earth space and seismic activity was discovered at the end of 1980s in MARIA experiment on board SALYUT-7 orbital station. Basing on 15 years investigations of high energy charged particles fluxes dynamics in magnetosphere by means of instruments installed on spacecraft it was

  17. Origin of the high energy cosmic neutrino background.

    PubMed

    Dado, Shlomo; Dar, Arnon

    2014-11-01

    The diffuse background of very high energy extraterrestrial neutrinos recently discovered with IceCube is compatible with that expected from cosmic ray interactions in the Galactic interstellar medium plus that expected from hadronic interactions near the source and in the intergalactic medium of the cosmic rays which have been accelerated by the jets that produce gamma ray bursts. PMID:25415894

  18. On the generation of delta-rays in detectors for high-energy cosmic-ray nuclei

    NASA Technical Reports Server (NTRS)

    Swordy, S. P.; Muller, D.; Have, A. T.

    1983-01-01

    A common problem in detectors for cosmic-ray nuclei is the generation of energetic knock-on electrons by an incident nucleus. These electrons may produce additional signals which can obscure the true nature of the signal from the nucleus itself. In this paper, Monte Carlo simulations of these effects are discussed in the University of Chicago CRNE instrument for Spacelab-2, and show that they do not impair the performance of the transition radiation detector as designed. Some qualitative properties of delta-ray effects are identified, which are of use to other experimenters in this field.

  19. Fermi LAT Observation of Diffuse Gamma-Rays Produced through Interactions Between Local Interstellar Matter and High Energy Cosmic Rays

    SciTech Connect

    Abdo, A.A.; /Naval Research Lab, Wash., D.C. /Federal City Coll.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ajello, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Atwood, W.B.; /UC, Santa Cruz; Axelsson, M.; /Stockholm U. /Stockholm U., OKC; Baldini, L.; /INFN, Pisa; Ballet, J.; /DAPNIA, Saclay; Barbiellini, G.; /INFN, Trieste /Trieste U.; Bastieri, D.; /INFN, Padua /Padua U.; Baughman, B.M.; /Ohio State U.; Bechtol, K.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bellazzini, R.; /INFN, Pisa; Berenji, B.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bloom, E.D.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bregeon, J.; /INFN, Pisa; Brez, A.; /INFN, Pisa; Brigida, M.; /Bari U. /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Burnett, T.H.; /Washington U., Seattle /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /IASF, Milan /Milan Polytechnic /Royal Inst. Tech., Stockholm /Stockholm U., OKC /DAPNIA, Saclay /INFN, Perugia /Perugia U. /NASA, Goddard /Naval Research Lab, Wash., D.C. /George Mason U. /NASA, Goddard /INFN, Perugia /Perugia U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Montpellier U. /Stockholm U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm /ASDC, Frascati /Naval Research Lab, Wash., D.C. /INFN, Trieste /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /CENBG, Gradignan /CENBG, Gradignan /Montpellier U. /Bari U. /INFN, Bari /Ecole Polytechnique /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Trieste /Hiroshima U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Bari U. /INFN, Bari /INFN, Bari; /more authors..

    2012-03-30

    Observations by the Large Area Telescope (LAT) on the Fermi mission of diffuse {gamma}-rays in a mid-latitude region in the third quadrant (Galactic longitude l from 200{sup o} to 260{sup o} and latitude |b| from 22{sup o} to 60{sup o}) are reported. The region contains no known large molecular cloud and most of the atomic hydrogen is within 1 kpc of the solar system. The contributions of {gamma}-ray point sources and inverse Compton scattering are estimated and subtracted. The residual {gamma}-ray intensity exhibits a linear correlation with the atomic gas column density in energy from 100 MeV to 10 GeV. The measured integrated {gamma}-ray emissivity is (1.63 {+-} 0.05) x 10{sup -26} photons s{sup -1}sr{sup -1} H-atom{sup -1} and (0.66 {+-} 0.02) x 10{sup -26} photons s{sup -1}sr{sup -1} H-atom{sup -1} above 100 MeV and above 300 MeV, respectively, with an additional systematic error of {approx}10%. The differential emissivity from 100 MeV to 10 GeV agrees with calculations based on cosmic ray spectra consistent with those directly measured, at the 10% level. The results obtained indicate that cosmic ray nuclei spectra within 1 kpc from the solar system in regions studied are close to the local interstellar spectra inferred from direct measurements at the Earth within {approx}10%.

  20. A study of the composition of ultra-high-energy cosmic rays using the High-Resolution Fly's Eye

    NASA Astrophysics Data System (ADS)

    Archbold, Gregory Clark

    2002-11-01

    The composition of Ultra High Energy Cosmic Rays (UHECR) was studied with the High Resolution Fly's Eye cosmic ray observatory (HiRes). HiRes is an air fluorescence detector comprised of two sites separated by 12.6 km on the U.S. Army's Dugway Proving Ground in the West Desert of Utah. Utilizing the atmosphere as a calorimeter, the longitudinal development of Extensive Air Showers (EAS) is measured and the energies, composition, flux, and anisotropy in arrival direction of the highest energy particles are determined. The QGSJet01 and SIBYLL 2.1 hadronic interaction models were used in versions 6.005 and 6.010 of the CORSIKA event generator to determine which measurable EAS parameters were correlated with UHECR compositon and to study predicted elongation rates and Xmax distribution widths in the UHECR regime. The CORSIKA-generated EAS were incorporated directly into a detailed atmospheric and detector Monte Carlo. Data were collected in stereo between November 1999 and September 2001. The data were reconstructed using measurements of the atmosphere, well-determined geometry, a global profile fit, and a detailed Monte Carlo. Monte Carlo resolution is 30 gm/cm2 in Xmax and 13% in Energy. The Elongation Rate between 1017.7 eV and 1020 eV is 55.2 ± 5.0 (stat) ± 3.6 (sys). Xmax distribution widths are consistent with a slowly changing and predominantly light composition. A simple composition model containing only protons and iron nuclei was compared to QGSJet and SIBYLL. The best agreement between the model and the data is at 77% protons for QGSJet and 57% protons for SIBYLL.

  1. Nuclear interactions of super high energy cosmic-rays observed in mountain emulsion chambers

    Microsoft Academic Search

    S. G. Bayburina; A. S. Borisov; K. V. Cherdyntseva; Z. M. Guseva; V. G. Denisova; A. M. Dunaevskii; E. A. Kanevskaya; V. M. Maximenko; S. V. Pashkov; V. S. Puchkov; S. B. Shaulov; S. A. Slavatinsky; M. D. Smirnova; Yu. A. Smorodin; A. V. Urysson; N. G. Zelevinskaya; G. B. Zhdanov; L. G. Afanasjeva; L. T. Baradzei; E. I. Gorochova; I. P. Ivanenko; N. P. Iljina; G. B. Khristiansen; T. V. Lazareva; A. K. Managadze; E. A. Murzina; I. V. Rakobolskaya; T. M. Roganova; N. G. Ryabova; G. T. Zatsepin; R. A. Mukhamedshin; S. D. Cananov; L. A. Khisanishvili; N. N. Roinishvili; M. S. Svanidge; J. A. Tecliashvili; T. V. Varsimashvili; Z. A. Azimov; I. B. Bodojanov; N. E. Gubar; Yu. A. Gulov; F. Normuradov; Kh. Shobaronov; N. A. Dobrotin; Yu. A. Emeljanov; Yu. T. Lukin; B. F. Shorin; E. G. Zaitseva; S. A. Azimov; A. R. Dzhuraev; E. G. Mulladjanov; Kh. Nutritdinov; D. A. Talipov; I. Shamansurov; T. S. Juldashbaev; Z. Buja; E. Gladysz; J. Mazurkiewicz; S. Mikocki; M. Szarska; L. Zawiejski; H. Bielawska; R. Juskiewicz; J. L. Kacperski; A. Krys; J. Malinowski; K. Milczarek; J. Sroka; A. Tomaszewski; J. A. Wrotniak; K. Maluszynska; Z. Wlodarczyk; M. Akashi; M. Amenomori; E. Konishi; H. Nanjo; Z. Watanabe; K. Mizutani; K. Kasahara; S. Torii; T. Yuda; T. Shirai; N. Tateyama; T. Taira; I. Mito; M. Shibata; H. Sugimoto; K. Taira; N. Hotta; M. Ballester; C. Santos; J. Bellandi Filho; J. A. Chinellato; C. Dobrigkeit; C. M. G. Lattes; A. Marques; M. J. Menon; C. E. Navia O; K. Sawayanagi; E. Silva; E. H. Shibuya; A. Turtelli; N. M. Amato; F. M. Oliveira Castro; R. H. C. Maldonado; H. Aoki; Y. Fuyimoto; S. Hasegawa; H. Kumano; H. Semba; T. Tabuki; M. Tamada; K. Tanaka; S. Yamashita; N. Arata; T. Shibata; K. Yokoi; A. Ohsawa

    1981-01-01

    Here we present a summary of joint discussions on the results of three mountain experiments with large-scale emulsion chambers, at Pamir, Mt. Fuji and Chacaltaya. Observations cover gamma quanta, hadrons and their clusters (called ``families''). The following topics are covered, concerning the characteristics of nuclear interactions the energy region 1014-1016 eV: (i) rapid dissipation seen in atmospheric diffusion of high-energy

  2. Solar panels as air Cherenkov detectors for extremely high energy cosmic rays

    E-print Network

    Cecchini, S; Esposti, L D; Giacomelli, G; Guerra, M; Lax, I; Mandrioli, G; Parretta, A; Sarno, A; Schioppo, R; Sorel, M; Spurio, M

    2000-01-01

    Increasing interest towards the observation of the highest energy cosmic rayshas motivated the development of new detection techniques. The properties ofthe Cherenkov photon pulse emitted in the atmosphere by these very rareparticles indicate low-cost semiconductor detectors as good candidates fortheir optical read-out. The aim of this paper is to evaluate the viability of solar panels for thispurpose. The experimental framework resulting from measurements performed withsuitably-designed solar cells and large conventional photovoltaic areas ispresented. A discussion on the obtained and achievable sensitivities follows.

  3. Multi-channel analog processor with 5×10 5 : 1 dynamic range for registration of interaction at super-high energies in the cosmic rays

    NASA Astrophysics Data System (ADS)

    Eremenko, Yu. A.; Kalinin, Yu. G.; Mart?anov, I. S.; Sadykov, T. Kh.; Zastrozhnova, N. N.

    2001-02-01

    This paper describes a wide dynamic range, multi-channel analog processor for registration and data processing of interactions at super-high energies from an ionization calorimeter of 44 m 2 area for experiments with cosmic rays at the altitude of 3340 m. It will enable one to calibrate the data of X-ray films under lead even in the cases of so called "halo" formation (Yu.A. Eremenko, Thesis, Tashkent 1989).

  4. Ultra High Energy Cosmic Rays, Z-Shower and Neutrino Astronomy by Horizontal-Upward Tau Air-Showers

    E-print Network

    D. Fargion

    2003-06-24

    Ultra High Cosmic Rays (UHECR) Astronomy may be correlated to a primary parental Neutrino Astronomy: indeed any far BL Lac Jet or GRB, sources of UHECR, located at cosmic edges, may send its signal, overcoming the severe GZK cut-off, by help of UHE ZeV energetic neutrino primary. These UHE neutrino scattering on relic light ones (spread on wide Hot Local Groups Halos) maybe fine-tuned : E_(nu) =(M_Z)^2/m_(nu) = 4 10^(22) eV *((0.1eV)/m_(nu)), to combine at once the observed light neutrino masses and the UHECR spectra, leading to a relativistic Z-Shower in Hot Dark Halos (e few tens Mpc wide) whose final nuclear component traces the UHECR event on Earth. Therefore UHECR (with no longer volme GZK constrains) may point to far BL Lac sources. This Z-Burst (Z-Shower) model calls for large neutrino fluxes. Even if Nature do not follow the present Z-model, UHECR while being cut-off by Big Bang Radiation, must produce a minimal UHE neutrino flux, the GZK neutrino secondaries. For both reasons such UHE Neutrino Astronomy must be tested on Earth. Lowest High Energy Astronomy is searched by AMANDA, ANTARES underground deterctors by muons tracks. We suggest a complementary higher energy Neutrino Tau Astronomy inducing Horizontal and Upward Tau AirShowers. Possible early evidence of such a New Neutrino UPTAUs (Upward Tau Showers at PeVs energies) Astronomy may be in BATSE records of Upward Terrestrial Gamma Flashes. Future signals must be found in detectors as EUSO, seeking Upward-Horizontal events: indeed even minimal, guaranteed, GZK neutrino fluxes may be better observed if EUSO threshold reaches 10^(19) eV by enlarging its telescope size.

  5. Measurement of the high energy cosmic ray electron spectrum with the Fermi Large Area Telescope

    Microsoft Academic Search

    F. Loparco

    2010-01-01

    The Large Area Telescope (LAT) onboard the Fermi satellite is composed by 16 identical tower modules, each consisting of a silicon strip tracker (TKR) interleaved with tungsten foils and followed by a CsI crystal hodoscopic calorimeter (CAL), surrounded by a segmented anticoincidence scintillator detector (ACD). Even though it was designed to be a high sensitivity gamma-ray telescope, the Fermi LAT

  6. Observation of very high energy cosmic-ray families in emulsion chambers at high mountain altitudes (I)

    Microsoft Academic Search

    L. T. Baradzei; A. S. Borisov; K. V. Cherdyntseva; Z. M. Guseva; V. G. Denisova; N. A. Dobrotin; A. M. Dunaevsky; E. A. Kanevskaya; S. A. Karpova; V. M. Maximenko; R. A. Nam; V. S. Puchkov; S. A. Slavatinsky; M. D. Smirnova; Yu. A. Smorodin; A. V. Uryson; N. G. Zelevinskaya; M. V. Zimin; G. B. Zhdanov; I. A. Mikhailova; R. A. Mukhamedshin; O. E. Doroshenko; L. P. Nikolaeva; L. V. Sukhov; G. T. Zatsepin; T. P. Amineva; G. F. Fedorova; I. P. Ivanenko; N. P. Iljina; V. V. Kopenkin; A. K. Managadze; E. G. Popova; I. V. Rakobolskaya; T. M. Roganova; O. P. Strogova; L. G. Sveshnikova; L. Kh. Chadranyan; L. A. Khisanishvili; N. N. Roinishvili; M. S. Svanidze; Z. A. Azimov; I. B. Bobodjanov; N. E. Gubar; Yu. A. Gulov; F. Normuradov; D. A. Khalilov; Sh. Myrtojieva; E. G. Mullajanov; A. N. Nosov; Kh. Nuritdinov; T. S. Yuldashbaev; Yu. A. Emelyanov; H. Bielawska; J. Malinowski; J. Maciaszczyk; A. Krys; M. Pluta; A. Tomaszewski; Z. Wlodarczyk; J. A. Chinellato; C. Dobrigkeit; J. Bellandi Filho; A. C. Fauth; C. M. G. Lattes; M. J. Menon; C. E. Navia O; K. Sawayanagi; E. H. Shibuya; A. Turtelli; N. M. Amato; N. Arata; F. M. Oliveira Castro; R. H. C. Maldonado; H. Aoki; Y. Fujimoto; Y. Funayama; S. Hasegawa; H. Kumano; H. Semba; M. Tamada; S. Yamashita; T. Shibata; K. Yokoi; A. Ohsawa

    1992-01-01

    Characteristics of cosmic-ray hadronic interactions in the 1015 - 1017 eV range are studied by observing a total of 429 cosmic-ray families of visible energy greater than 100 TeV found in emulsion chamber experiments at high mountain altitudes, Chacaltaya (5200 m above sea level) and the Pamirs (4300 m above sea level). Extensive comparisons were made with simulated families based

  7. THE ROLE OF STRUCTURED MAGNETIC FIELDS ON CONSTRAINING PROPERTIES OF TRANSIENT SOURCES OF ULTRA-HIGH-ENERGY COSMIC RAYS

    SciTech Connect

    Takami, Hajime [Max Planck Institute for Physics, Foehringer Ring 6, 80805 Munich (Germany); Murase, Kohta, E-mail: takami@mpp.mpg.de [Center for Cosmology and AstroParticle Physics, The Ohio State University, 191 W. Woodruff Ave., Columbus, OH 43210 (United States)

    2012-03-20

    We study how the properties of transient sources of ultra-high-energy cosmic rays (UHECRs) can be accessed by exploiting UHECR experiments, taking into account the propagation of UHECRs in magnetic structures which the sources are embedded in, i.e., clusters of galaxies and filamentary structures. Adopting simplified analytical models, we demonstrate that the structured extragalactic magnetic fields (EGMFs) play crucial roles in unveiling the properties of the transient sources. These EGMFs unavoidably cause significant delay in the arrival time of UHECRs as well as the Galactic magnetic field, even if the strength of magnetic fields in voids is zero. Then, we show that, given good knowledge on the structured EGMFs, UHECR observations with high statistics above 10{sup 20} eV allow us to constrain the generation rate of transient UHECR sources and their energy input per burst, which can be compared with the rates and energy release of known astrophysical phenomena. We also demonstrate that identifying the energy dependence of the apparent number density of UHECR sources at the highest energies is crucial to such transient sources. Future UHECR experiments with extremely large exposure are required to reveal the nature of transient UHECR sources.

  8. The Lateral Trigger Probability function for the ultra-high energy cosmic ray showers detected by the Pierre Auger Observatory

    SciTech Connect

    Abreu, P.; /Lisbon, IST /Lisbon, LIFEP; Aglietta, M.; /INFN, Turin /Turin Observ. /Turin U.; Ahn, E.J.; /Fermilab; Albuquerque, I.F.M.; /Sao Paulo U.; Allard, D.; /APC, Paris; Allekotte, I.; /Centro Atomico Bariloche /Balseiro Inst., San Carlos de Bariloche; Allen, J.; /New York U.; Allison, P.; /Ohio State U.; Alvarez Castillo, J.; /Mexico U.; Alvarez-Muniz, J.; /Santiago de Compostela U.; Ambrosio, M.; /INFN, Naples /Naples U. /Nijmegen U., IMAPP

    2011-01-01

    In this paper we introduce the concept of Lateral Trigger Probability (LTP) function, i.e., the probability for an Extensive Air Shower (EAS) to trigger an individual detector of a ground based array as a function of distance to the shower axis, taking into account energy, mass and direction of the primary cosmic ray. We apply this concept to the surface array of the Pierre Auger Observatory consisting of a 1.5 km spaced grid of about 1600 water Cherenkov stations. Using Monte Carlo simulations of ultra-high energy showers the LTP functions are derived for energies in the range between 10{sup 17} and 10{sup 19} eV and zenith angles up to 65{sup o}. A parametrization combining a step function with an exponential is found to reproduce them very well in the considered range of energies and zenith angles. The LTP functions can also be obtained from data using events simultaneously observed by the fluorescence and the surface detector of the Pierre Auger Observatory (hybrid events). We validate the Monte Carlo results showing how LTP functions from data are in good agreement with simulations.

  9. The Lateral Trigger Probability function for the Ultra-High Energy Cosmic Ray Showers detected by the Pierre Auger Observatory

    E-print Network

    The Pierre Auger Collaboration; P. Abreu; M. Aglietta; E. J. Ahn; I. F. M. Albuquerque; D. Allard; I. Allekotte; J. Allen; P. Allison; J. Alvarez Castillo; J. Alvarez-Muñiz; M. Ambrosio; A. Aminaei; L. Anchordoqui; S. Andringa; T. Anti?i?; A. Anzalone; C. Aramo; E. Arganda; F. Arqueros; H. Asorey; P. Assis; J. Aublin; M. Ave; M. Avenier; G. Avila; T. Bäcker; M. Balzer; K. B. Barber; A. F. Barbosa; R. Bardenet; S. L. C. Barroso; B. Baughman; J. Bäuml; J. J. Beatty; B. R. Becker; K. H. Becker; A. Bellétoile; J. A. Bellido; S. BenZvi; C. Berat; X. Bertou; P. L. Biermann; P. Billoir; F. Blanco; M. Blanco; C. Bleve; H. Blümer; M. Bohá?ová; D. Boncioli; C. Bonifazi; R. Bonino; N. Borodai; J. Brack; P. Brogueira; W. C. Brown; R. Bruijn; P. Buchholz; A. Bueno; R. E. Burton; K. S. Caballero-Mora; L. Caramete; R. Caruso; A. Castellina; O. Catalano; G. Cataldi; L. Cazon; R. Cester; J. Chauvin; S. H. Cheng; A. Chiavassa; J. A. Chinellato; A. Chou; J. Chudoba; R. W. Clay; M. R. Coluccia; R. Conceição; F. Contreras; H. Cook; M. J. Cooper; J. Coppens; A. Cordier; S. Coutu; C. E. Covault; A. Creusot; A. Criss; J. Cronin; A. Curutiu; S. Dagoret-Campagne; R. Dallier; S. Dasso; K. Daumiller; B. R. Dawson; R. M. de Almeida; M. De Domenico; C. De Donato; S. J. de Jong; G. De La Vega; W. J. M. de Mello Junior; J. R. T. de Mello Neto; I. De Mitri; V. de Souza; K. D. de Vries; G. Decerprit; L. del Peral; M. del Río; O. Deligny; H. Dembinski; N. Dhital; C. Di Giulio; J. C. Diaz; M. L. Díaz Castro; P. N. Diep; C. Dobrigkeit; W. Docters; J. C. D'Olivo; P. N. Dong; A. Dorofeev; J. C. dos Anjos; M. T. Dova; D. D'Urso; I. Dutan; J. Ebr; R. Engel; M. Erdmann; C. O. Escobar; J. Espadanal; A. Etchegoyen; P. Facal San Luis; I. Fajardo Tapia; H. Falcke; G. Farrar; A. C. Fauth; N. Fazzini; A. P. Ferguson; A. Ferrero; B. Fick; A. Filevich; A. Filip?i?; S. Fliescher; C. E. Fracchiolla; E. D. Fraenkel; U. Fröhlich; B. Fuchs; R. Gaior; R. F. Gamarra; S. Gambetta; B. García; D. García Gámez; D. Garcia-Pinto; A. Gascon; H. Gemmeke; K. Gesterling; P. L. Ghia; U. Giaccari; M. Giller; H. Glass; M. S. Gold; G. Golup; F. Gomez Albarracin; M. Gómez Berisso; P. Gonçalves; D. Gonzalez; J. G. Gonzalez; B. Gookin; D. Góra; A. Gorgi; P. Gouffon; S. R. Gozzini; E. Grashorn; S. Grebe; N. Griffith; M. Grigat; A. F. Grillo; Y. Guardincerri; F. Guarino; G. P. Guedes; A. Guzman; J. D. Hague; P. Hansen; D. Harari; S. Harmsma; J. L. Harton; A. Haungs; T. Hebbeker; D. Heck; A. E. Herve; C. Hojvat; N. Hollon; V. C. Holmes; P. Homola; J. R. Hörandel; A. Horneffer; M. Hrabovský; T. Huege; A. Insolia; F. Ionita; A. Italiano; C. Jarne; S. Jiraskova; M. Josebachuili; K. Kadija; K. H. Kampert; P. Karhan; P. Kasper; B. Kégl; B. Keilhauer; A. Keivani; J. L. Kelley; E. Kemp; R. M. Kieckhafer; H. O. Klages; M. Kleifges; J. Kleinfeller; J. Knapp; D. -H. Koang; K. Kotera; N. Krohm; O. Krömer; D. Kruppke-Hansen; F. Kuehn; D. Kuempel; J. K. Kulbartz; N. Kunka; G. La Rosa; C. Lachaud; P. Lautridou; M. S. A. B. Leão; D. Lebrun; P. Lebrun; M. A. Leigui de Oliveira; A. Lemiere; A. Letessier-Selvon; I. Lhenry-Yvon; K. Link; R. López; A. Lopez Agüera; K. Louedec; J. Lozano Bahilo; L. Lu; A. Lucero; M. Ludwig; H. Lyberis; M. C. Maccarone; C. Macolino; S. Maldera; D. Mandat; P. Mantsch; A. G. Mariazzi; J. Marin; V. Marin; I. C. Maris; H. R. Marquez Falcon; G. Marsella; D. Martello; L. Martin; H. Martinez; O. Martínez Bravo; H. J. Mathes; J. Matthews; J. A. J. Matthews; G. Matthiae; D. Maurizio; P. O. Mazur; G. Medina-Tanco; M. Melissas; D. Melo; E. Menichetti; A. Menshikov; P. Mertsch; C. Meurer; S. Mi?anovi?; M. I. Micheletti; W. Miller; L. Miramonti; L. Molina-Bueno; S. Mollerach; M. Monasor; D. Monnier Ragaigne; F. Montanet; B. Morales; C. Morello; E. Moreno; J. C. Moreno; C. Morris; M. Mostafá; C. A. Moura; S. Mueller; M. A. Muller; G. Müller; M. Münchmeyer; R. Mussa; G. Navarra ‡; J. L. Navarro; S. Navas; P. Necesal; L. Nellen; A. Nelles; J. Neuser; P. T. Nhung; L. Niemietz; N. Nierstenhoefer; D. Nitz; D. Nosek; L. Nožka; M. Nyklicek; J. Oehlschläger; A. Olinto; P. Oliva; V. M. Olmos-Gilbaja; M. Ortiz; N. Pacheco; D. Pakk Selmi-Dei; M. Palatka; J. Pallotta; N. Palmieri; G. Parente; E. Parizot; A. Parra; R. D. Parsons; S. Pastor; T. Paul; M. Pech; J. P?kala; R. Pelayo; I. M. Pepe; L. Perrone; R. Pesce; E. Petermann; S. Petrera; P. Petrinca; A. Petrolini; Y. Petrov; J. Petrovic; C. Pfendner; N. Phan; R. Piegaia; T. Pierog; P. Pieroni; M. Pimenta; V. Pirronello; M. Platino; V. H. Ponce; M. Pontz; P. Privitera; M. Prouza; E. J. Quel; S. Querchfeld; J. Rautenberg; O. Ravel; D. Ravignani; B. Revenu; J. Ridky; S. Riggi; M. Risse; P. Ristori; H. Rivera; V. Rizi; J. Roberts; C. Robledo; W. Rodrigues de Carvalho; G. Rodriguez; J. Rodriguez Martino; J. Rodriguez Rojo

    2011-11-28

    In this paper we introduce the concept of Lateral Trigger Probability (LTP) function, i.e., the probability for an extensive air shower (EAS) to trigger an individual detector of a ground based array as a function of distance to the shower axis, taking into account energy, mass and direction of the primary cosmic ray. We apply this concept to the surface array of the Pierre Auger Observatory consisting of a 1.5 km spaced grid of about 1600 water Cherenkov stations. Using Monte Carlo simulations of ultra-high energy showers the LTP functions are derived for energies in the range between 10^{17} and 10^{19} eV and zenith angles up to 65 degs. A parametrization combining a step function with an exponential is found to reproduce them very well in the considered range of energies and zenith angles. The LTP functions can also be obtained from data using events simultaneously observed by the fluorescence and the surface detector of the Pierre Auger Observatory (hybrid events). We validate the Monte-Carlo results showing how LTP functions from data are in good agreement with simulations.

  10. An extended universality of electron distributions in cosmic ray showers of high energies and its application

    NASA Astrophysics Data System (ADS)

    Giller, Maria; ?mia?kowski, Andrzej; Wieczorek, Grzegorz

    2015-01-01

    It is shown that the shape of any electron distribution in a high energy air shower is the same in all such showers, if taken at the same age, independently of the primary energy, mass and thus, of the interaction model. A universal behaviour has been also found within a single shower, such that the lateral distributions of electrons with fixed energies, at various shower ages, can be described by a single function of only one variable. The angular distributions of electrons with a fixed energy can be represented, at a given lateral distance, by a function of the product ?·E? only, which is explained by a model of small angle electron scattering with simplified energy losses. These results have been obtained by Monte Carlo simulations of the extensive air showers. The electron universality can be used as a method for determining the longitudinal profile of any single shower from its optical images measured by the fluorescence light technique, which is particularly useful with showers observed with large fraction of the Cherenkov light.

  11. Magnetars in the Metagalaxy: An Origin for Ultra-High-Energy Cosmic Rays in the Nearby Universe

    NASA Astrophysics Data System (ADS)

    Arons, Jonathan

    2003-06-01

    I show that the relativistic winds of newly born magnetars (neutron stars with petagauss surface magnetic fields) with initial spin rates close to the centrifugal breakup limit, occurring in all normal galaxies with massive star formation, can provide a source of ultrarelativistic light ions with an E-1 injection spectrum, steepening to E-2 at higher energies, with an upper cutoff at 1021-1022 eV. Interactions with the cosmic microwave background yield a spectrum at the Earth that compares favorably with the spectrum of ultra-high-energy cosmic rays (UHECRs) observed at energies up to a few times 1020 eV. The fit to the observations suggests that ~5%-10% of the magnetars are born with rotation rates and voltages sufficiently high to allow the acceleration of the UHECR. The form the spectrum incident on the Earth takes depends sensitively on the mechanism and the magnitude of gravitational wave losses during the early spin-down of these neutron stars: pure electromagnetic spin-down (the E-1 injection spectrum) yields a GZK feature [a flattening of the E3J(E) spectrum] below 1020 eV, rather than a cutoff, while a moderate GZK cutoff appears if gravitational wave losses are strong enough to steepen the injection spectrum above 1020 eV. The flux above 1020 eV comes from magnetars in relatively nearby galaxies (D<50 Mpc). I outline the probable physics of acceleration of such particles in a magnetar's wind: it is a form of ``surf-riding'' in the approximately force-free fields of the wind. I also show how the high-energy particles can escape with small energy losses from the magnetars' natal supernovae. In particular, I show that the electromagnetic energy emitted by the magnetar ``shreds'' the supernova envelope in times short enough to allow most of the relativistic energy to escape largely unimpeded into the surrounding interstellar medium, where it drives a relativistic blast wave that expands to parsec scale before slowing down to nonrelativistic speeds. I also show that since the ions are accelerated in a region where the magnetic field has the structure of a strong electromagnetic wave but propagate at larger radii through a region of weaker magnetic field near the rotational equator of the outflow, the ultra-high-energy particles escape with negligible adiabatic and radiation losses. The requirement that the magnetars' relativistic winds not overproduce interstellar supershells and unusually large supernova remnants suggests that most of the initial spin-down energy is radiated in kilohertz gravitational waves for several hours after each supernova. For typical distances to events that contribute to E>100 EeV air showers, the model predicts gravitational wave strains ~3×10-21. Such bursts of gravitational radiation should correlate with bursts of ultra-high-energy particles. The Auger experiment should see bursts of particles with energy above 100 EeV every few years.

  12. High energy gamma ray astronomy

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.

    1974-01-01

    The SAS-2 gamma ray experiment and its detection of celestial gamma rays are described. Data also cover intensity of high energy gamma rays, gamma ray distribution, gamma ray origin, and diffuse radiation.

  13. Measurement of the shadowing of high-energy cosmic rays by the Moon: A search for TeV-energy antiprotons

    Microsoft Academic Search

    P. Achard; O. Adriani; M. Aguilar-Benitez; J. Alcaraz; G. Alemanni; J. Allaby; A. Aloisio; M. G. Alviggi; H. Anderhub; V. P. Andreev; F. Anselmo; A. Arefiev; T. Azemoon; P. Bagnaia; A. Bajo; G. Baksay; L. Baksay; J. Bähr; S. V. Baldew; S. Banerjee; Sw. Banerjee; A. Barczyk; R. Barillère; P. Bartalini; M. Basile; N. Batalova; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; L. Bellucci; R. Berbeco; J. Berdugo; P. Berges; B. Bertucci; M. Biasini; M. Biglietti; A. Biland; J. J. Blaising; S. C. Blyth; G. J. Bobbink; A. Böhm; L. Boldizsar; B. Borgia; S. Bottai; D. Bourilkov; M. Bourquin; S. Braccini; J. G. Branson; F. Brochu; J. D. Burger; W. J. Burger; X. D. Cai; M. Capell; G. Cara Romeo; G. Carlino; A. Cartacci; J. Casaus; F. Cavallari; N. Cavallo; C. Cecchi; M. Cerrada; T. Chiarusi; Y. H. Chang; M. Chemarin; A. Chen; G. Chen; H. F. Chen; H. S. Chen; G. Chiefari; L. Cifarelli; F. Cindolo; I. Clare; G. Coignet; N. Colino; S. Costantini; B. de la Cruz; S. Cucciarelli; R. de Asmundis; P. Déglon; J. Debreczeni; A. Degré; K. Dehmelt; D. della Volpe; E. Delmeire; P. Denes; F. DeNotaristefani; A. De Salvo; M. Diemoz; M. Dierckxsens; L. K. Ding; C. Dionisi; M. Dittmar; A. Doria; M. T. Dova; D. Duchesneau; M. Duda; I. Duran; B. Echenard; A. Eline; A. El Hage; H. El Mamouni; A. Engler; F. J. Eppling; P. Extermann; G. Faber; M. A. Falagan; S. Falciano; A. Favara; J. Fay; O. Fedin; M. Felcini; T. Ferguson; H. Fesefeldt; E. Fiandrini; J. H. Field; F. Filthaut; P. H. Fisher; W. Fisher; I. Fisk; G. Forconi; K. Freudenreich; C. Furetta; Yu. Galaktionov; S. N. Ganguli; P. Garcia-Abia; M. Gataullin; S. Gentile; Z. F. Gong; H. J. Grabosch; G. Grenier; O. Grimm; H. Groenstege; M. W. Gruenewald; M. Guida; Y. N. Guo; V. K. Gupta; A. Gurtu; L. J. Gutay; D. Haas; Ch. Haller; D. Hatzifotiadou; Y. Hayashi; Z. X. He; T. Hebbeker; A. Hervé; J. Hirschfelder; H. Hofer; M. Hohlmann; G. Holzner; S. R. Hou; A. X. Huo; N. Ito; B. N. Jin; P. Jindal; C. L. Jing; L. W. Jones; P. de Jong; I. Josa-Mutuberría; V. Kantserov; M. Kaur; S. Kawakami; M. N. Kienzle-Focacci; J. K. Kim; J. Kirkby; W. Kittel; A. Klimentov; E. Kok; A. Korn; M. Kopal; V. Koutsenko; M. Kräber; H. H. Kuang; R. W. Kraemer; A. Krüger; J. Kuijpers; A. Kunin; P. Ladron de Guevara; I. Laktineh; G. Landi; M. Lebeau; A. Lebedev; P. Lebrun; P. Lecomte; P. Le Coultre; J. M. Le Goff; Y. Lei; H. Leich; R. Leiste; M. Levtchenko; P. Levtchenko; C. Li; L. Li; Z. C. Li; S. Likhoded; C. H. Lin; W. T. Lin; F. L. Linde; Z. A. Liu; W. Lohmann; E. Longo; Y. S. Lu; C. Luci; L. Luminari; W. Lustermann; W. G. Ma; X. H. Ma; Y. Q. Ma; L. Malgeri; A. Malinin; C. Maña; J. Mans; J. P. Martin; F. Marzano; K. Mazumdar; R. R. McNeil; S. Mele; X. W. Meng; L. Merola; M. Meschini; W. J. Metzger; A. Mihul; A. van Mil; H. Milcent; G. Mirabelli; J. Mnich; G. B. Mohanty; B. Monteleoni; G. S. Muanza; A. J. M. Muijs; B. Musicar; M. Musy; S. Nagy; R. Nahnhauer; V. A. Naumov; S. Natale; M. Napolitano; F. Nessi-Tedaldi; H. Newman; A. Nisati; T. Novak; H. Nowak; R. Ofierzynski; G. Organtini; I. Pal; C. Palomares; P. Paolucci; R. Paramatti; J.-F. Parriaud; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; M. Pedace; S. Pensotti; D. Perret-Gallix; B. Petersen; D. Piccolo; F. Pierella; M. Pieri; M. Pioppi; P. A. Piroué; E. Pistolesi; V. Plyaskin; M. Pohl; V. Pojidaev; J. Pothier; D. Prokofiev; J. Quartieri; C. R. Qing; G. Rahal-Callot; M. A. Rahaman; P. Raics; N. Raja; R. Ramelli; P. G. Rancoita; R. Ranieri; A. Raspereza; K. C. Ravindran; P. Razis; D. Ren; M. Rescigno; S. Reucroft; P. Rewiersma; S. Riemann; K. Riles; B. P. Roe; A. Rojkov; L. Romero; A. Rosca; C. Rosemann; S. Rosier-Lees; C. Rosenbleck; S. Roth; J. A. Rubio; G. Ruggiero; H. Rykaczewski; R. Saidi; A. Sakharov; S. Saremi; J. Salicio; E. Sanchez; C. Schäfer; V. Schegelsky; V. Schmitt; B. Schoeneich; H. Schopper; D. J. Schotanus; C. Sciacca; L. Servoli; C. Q. Shen; S. Shevchenko; N. Shivarov; V. Shoutko; E. Shumilov; A. Shvorob; D. Son; C. Souga; P. Spillantini; M. Steuer; D. P. Stickland; B. Stoyanov; A. Straessner; K. Sudhakar; H. Sulanke; G. Sultanov; L. Z. Sun; S. Sushkov; H. Suter; J. D. Swain; Z. Szillasi; X. W. Tang; P. Tarjan; L. Tauscher; B. Tellili; D. Teyssier; C. Timmermans; Samuel C. C. Ting; S. M. Ting; S. C. Tonwar; J. Tóth; G. Trowitzsch; C. Tully; K. L. Tung; J. Ulbricht; M. Unger; E. Valente; H. Verkooijen; R. T. Van de Walle; R. Vasquez; V. Veszpremi; G. Vesztergombi; I. Vetlitsky; D. Vicinanza; G. Viertel; S. Villa; M. Vivargent; S. Vlachos; I. Vodopianov; H. Vogel; H. Vogel; I. Vorobiev; A. A. Vorobyov; M. Wadhwa; R. G. Wang; Q. Wang; X. L. Wang; X. W. Wang; Z. M. Wang; Z. M. Wang; R. van Wijk; T. A. M. Wijnen; H. Wilkens; S. Wynhoff; L. Xia; Y. P. Xu; J. S. Xu; Z. Z. Xu; J. Yamamoto; B. Z. Yang; C. G. Yang; H. J. Yang; M. Yang; X. F. Yang; Z. G. Yao; S. C. Yeh; Z. Q. Yu

    2005-01-01

    The shadowing of high-energy cosmic rays by the Moon has been observed with a significance of 9.4 standard deviations with the L3+C muon spectrometer at CERN. A significant effect of the Earth magnetic field is observed. Since no event deficit on the east side of the Moon has been observed, an upper limit at 90% confidence level on the antiproton

  14. Photodetection Aspects of JEM-EUSO and Studies of the Ultra-High Energy Cosmic Ray Sky

    E-print Network

    Carl Blaksley

    2014-06-23

    In this thesis, an introduction to the Ultra-High Energy Cosmic Ray (UHECR) field is given, including air shower physics, UHECR astrophysics, and experimental techniques. The current questions in UHECR physics are mentioned, along with the experimental challenges encountered in the field. The physics of air fluorescence is also presented, and the JEM-EUSO experiment is introduced in detail. The original contributions in this thesis are divided into experimental work on photodetection aspects of JEM-EUSO and phenomenological studies of UHECR composition and source statistics. A comprehensive introduction to photomultiplier tubes (PMTs) and single photoelectron counting are given, and the measurement of PMT efficiency with an uncertainty of a few percent is discussed in detail. An experimental setup for measuring the air fluorescence yield is also introduced, and tests of the EUSO-Balloon high voltage power supply prototype are presented. A setup for sorting the JEM-EUSO PMTs is developed, including the assembly and calibration of data acquisition hardware and the development of acquisition and analysis software. This system is used to perform an absolute calibration of the EUSO-Balloon focal surface, along with measurements of the PMT pixel width and dead-space. In the phenomenological part of this work, it is shown that a distribution of source maximum energies must be considered in order to understand the energy spectrum and the composition of UHECRs. The number of sources which can be expected to contribute to the UHECR sky is also studied, finding that on the order of 1 source(s) contributes more than 50% of the flux at 100 EeV.

  15. Research on nucleon decay neutrino oscillations and super high energy particles. [Homestake Large Underground Scintillation Hodoscope and Cosmic Ray Telescope

    SciTech Connect

    Lande, K.

    1992-03-01

    In this final report of the Homestake Large Underground Scintillation Hodoscope and Cosmic Ray Telescope, are given a summary of the results obtained while construction and operation of this detector were supported by the Department of Energy, the activities of this detector since cessation of DOE support, and future plans for this instrument.

  16. Frontiers in Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Anchordoqui, Luis A.; Dermer, Charles D.; Ringwald, Andreas

    2006-02-01

    This rapporteur review covers selected results presented in the Parallel Session HEA2 (High Energy Astrophysics 2) of the 10th Marcel Grossmann Meeting on General Relativity, held in Rio de Janeiro, Brazil, July 2003. The subtopics are: ultra high energy cosmic ray anisotropies, the possible connection of these energetic particles with powerful gamma ray bursts, and new exciting scenarios with a strong neutrino-nucleon interaction in the atmosphere.

  17. Frontiers in Cosmic Rays

    E-print Network

    Luis A. Anchordoqui; Charles D. Dermer; Andreas Ringwald

    2004-02-27

    This rapporteur review covers selected results presented in the Parallel Session HEA2 (High Energy Astrophysics 2) of the 10th Marcel Grossmann Meeting on General Relativity, held in Rio de Janeiro, Brazil, July 2003. The subtopics are: ultra high energy cosmic ray anisotropies, the possible connection of these energetic particles with powerful gamma ray bursts, and new exciting scenarios with a strong neutrino-nucleon interaction in the atmosphere.

  18. Data Analysis for the Measurement of High Energy Cosmic Ray Electron\\/Positron Spectrum with Fermi-LAT

    Microsoft Academic Search

    M. N. Mazziotta

    2009-01-01

    The Large Area Telescope (LAT) instrument on board the Fermi satellite consists of a multi-layer silicon-strip tracker interleaved with tungsten converters (TKR), followed by a CsI crystal hodoscopic calorimeter (CAL). Sixteen TKR and CAL modules are assembled in a 4$\\\\times$4 array. A segmented anticoincidence plastic scintillator (ACD) surrounds the TKRs. The primary cosmic-ray electron\\/positron energy spectrum has been measured from

  19. Fermi LAT Observation of Diffuse Gamma Rays Produced Through Interactions Between Local Interstellar Matter and High-energy Cosmic Rays

    Microsoft Academic Search

    A. A. Abdo; M. Ackermann; M. Ajello; W. B. Atwood; M. Axelsson; L. Baldini; J. Ballet; G. Barbiellini; D. Bastieri; B. M. Baughman; K. Bechtol; R. Bellazzini; B. Berenji; E. D. Bloom; E. Bonamente; A. W. Borgland; J. Bregeon; A. Brez; M. Brigida; P. Bruel; T. H. Burnett; G. A. Caliandro; R. A. Cameron; P. A. Caraveo; P. Carlson; J. M. Casandjian; C. Cecchi; Ö. Çelik; A. Chekhtman; C. C. Cheung; S. Ciprini; R. Claus; J. Cohen-Tanugi; J. Conrad; S. Cutini; C. D. Dermer; A. de Angelis; F. de Palma; S. W. Digel; E. do Couto e. Silva; P. S. Drell; R. Dubois; D. Dumora; C. Farnier; C. Favuzzi; S. J. Fegan; W. B. Focke; M. Frailis; Y. Fukazawa; S. Funk; P. Fusco; F. Gargano; D. Gasparrini; N. Gehrels; S. Germani; B. Giebels; N. Giglietto; F. Giordano; T. Glanzman; G. Godfrey; I. A. Grenier; M.-H. Grondin; J. E. Grove; L. Guillemot; S. Guiriec; Y. Hanabata; A. K. Harding; M. Hayashida; E. Hays; R. E. Hughes; G. Jóhannesson; A. S. Johnson; R. P. Johnson; W. N. Johnson; T. Kamae; H. Katagiri; N. Kawai; M. Kerr; J. Knödlseder; M. L. Kocian; F. Kuehn; M. Kuss; J. Lande; L. Latronico; M. Lemoine-Goumard; F. Longo; F. Loparco; B. Lott; M. N. Lovellette; P. Lubrano; A. Makeev; M. N. Mazziotta; J. E. McEnery; C. Meurer; P. F. Michelson; W. Mitthumsiri; T. Mizuno; A. A. Moiseev; C. Monte; M. E. Monzani; A. Morselli; I. V. Moskalenko; S. Murgia; P. L. Nolan; J. P. Norris; E. Nuss; T. Ohsugi; A. Okumura; N. Omodei; E. Orlando; J. F. Ormes; M. Ozaki; D. Paneque; J. H. Panetta; D. Parent; M. Pepe; M. Pesce-Rollins; F. Piron; M. Pohl; T. A. Porter; S. Rainò; R. Rando; M. Razzano; A. Reimer; O. Reimer; T. Reposeur; S. Ritz; L. S. Rochester; A. Y. Rodriguez; F. Ryde; H. F.-W. Sadrozinski; D. Sanchez; A. Sander; P. M. Saz Parkinson; T. L. Schalk; A. Sellerholm; C. Sgrò; D. A. Smith; P. D. Smith; G. Spandre; P. Spinelli; J.-L. Starck; F. W. Stecker; M. S. Strickman; A. W. Strong; D. J. Suson; H. Tajima; H. Takahashi; T. Takahashi; T. Tanaka; J. B. Thayer; J. G. Thayer; D. J. Thompson; L. Tibaldo; D. F. Torres; G. Tosti; A. Tramacere; Y. Uchiyama; T. L. Usher; V. Vasileiou; N. Vilchez; V. Vitale; A. P. Waite; P. Wang; B. L. Winer; K. S. Wood; T. Ylinen; M. Ziegler

    2009-01-01

    Observations by the Large Area Telescope (LAT) on the Fermi mission of diffuse gamma-rays in a mid-latitude region in the third quadrant (Galactic longitude l from 200° to 260° and latitude |b| from 22° to 60°) are reported. The region contains no known large molecular cloud and most of the atomic hydrogen is within 1 kpc of the solar system.

  20. Method to extract the primary cosmic ray spectrum from very high energy gamma-ray data and its application to SNR RX J1713.7-3946

    E-print Network

    F. L. Villante; F. Vissani

    2008-01-04

    Supernova remnants are likely to be the accelerators of the galactic cosmic rays. Assuming the correctness of this hypothesis, we develop a method to extract the parent cosmic ray spectrum from the VHE gamma ray flux emitted by supernova remnants (and other gamma transparent sources). Namely, we calculate semi-analytically the (inverse) operator which relates an arbitrary gamma ray flux to the parent cosmic ray spectrum, without relying on any theoretical assumption about the shape of the cosmic ray and/or photon spectrum. We illustrate the use of this technique by applying it to the young SNR RX J1713.7-3946 which has been observed by H.E.S.S. experiment during the last three years. Specific implementations of the method permit to use as an input either the parameterized VHE gamma ray flux or directly the raw data. The possibility to detect features in the cosmic rays spectrum and the error in the determination of the parent cosmic ray spectrum are also discussed.

  1. Ultra-High Energy Cosmic Neutrinos

    NASA Astrophysics Data System (ADS)

    Saltzberg, David

    2006-04-01

    Astrophysical processes appear to produce particles with energies of at least 10^19-20 eV. Yet extra-galactic astronomy appears to be limited for photons with energies above 10^14 eV due to absorption. Neutrino astronomy offers the possibility to perform extra-galactic astronomy to these energies and beyond without an absorption cutoff. In addition, the interactions of ultra-high energy (UHE) neutrinos of cosmic origin with local matter may reveal exotic new physics processes that are unavailable to modern accelerators. UHE neutrino telescopes based on optical detection techniques that are currently operating and under construction will soon have apertures on the scale of 10 km^3-sr with excellent thresholds. Radio and acoustic detection techniques have been demonstrated in laboratory experiments and are being used to instrument apertures from 10 to to 10,000 km^3-sr for neutrinos with energies above 10^16 eV. Neutrino telescopes based on radio detection include the RICE detectors placed on the Amanda strings at the South Pole. The GLUE antennas pointed at the Moon have set limits on the neutrino intensity at higher energies. The best sensitivity at the highest energies comes from the FORTE satellite which looked for interactions in Greenland ice. The upcoming ANITA long-duration balloon flights over Antarctica will be sensitive to neutrinos produced by the interactions of cosmic rays with the cosmic microwave background radiation. Using the acoustic technique, the SAUND collaboration recently performed a UHE neutrino search using hydrophones in the deep sea near the Bahamas. Investigations for even larger apertures include several other detection possibilities, including placing radio and acoustic sensors in large underground salt formations. The acoustic technique may find promise in solid media currently under investigation. The neutrino sensitivity of current and proposed telescopes based on optical, radio, acoustic techniques will be compared for both specific models and in a model-independent fashion.

  2. Study of ultra-high energy cosmic rays from the radio signal at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Maller, J.

    2013-11-01

    Deployed at the end of 2010 at the Pierre Auger Observatory, the first stage of the Auger Engineering Radio Array, AERA24, consists of 24 radio stations covering an area of 0.5 km^2. AERA measures the radio emission from cosmic-ray induced air showers. The amplitude of this radio emission is used to constrain the characteristics of the primary particle: arrival direction, energy and nature. These studies are possible thanks to an instrumentation development allowing self-triggered and externally-triggered measurements in the MHz domain and an improved understanding of radio emission processes. In May 2013, 100 new stations were installed to cover an area of ˜eq 6 km^2, for a total of 124 stations. This stage 2 will provide higher statistics and will enhance both the estimate of the nature of the primary cosmic ray and the energy resolution above 10^{17} eV as an addition to detectors such as the Auger fluorescence telescopes and particle detectors. We will present the main results obtained with the stage 1 of AERA and the current status of the experiment. We will end with a brief overview of the GHz-experiments installed at the Pierre Auger Observatory.

  3. Gamma Ray Bursts as Possible High Energy Sources

    E-print Network

    Charles D. Dermer

    2005-12-06

    Gamma-ray bursts are known to be sources of high-energy gamma rays, and are likely to be sources of high-energy cosmic rays and neutrinos. Following a short review of observations of GRBs at multi-MeV energies and above, the physics of leptonic and hadronic models of GRBs is summarized. Evidence for two components in BATSE and EGRET/TASC data suggest that GRBs are sources of high-energy cosmic rays. GLAST observations will reveal the high-energy gamma-ray power and energy releases from GRBs, and will provide detailed knowledge of anomalous high-energy emission components, but confirmation of cosmic ray acceleration must await 100 TeV -- PeV neutrino detection from GRBs.

  4. Diffuse fluxes of cosmic high-energy neutrinos

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.

    1979-01-01

    Production spectra of high-energy neutrinos from galactic cosmic-ray interactions with interstellar gas and extragalactic ultrahigh-energy cosmic-ray interactions with microwave blackbody photons are presented and discussed. These production processes involve the decay of charged pions and are thus related to the production of cosmic gamma rays from the decay of neutral pions. Estimates of the neutrino fluxes from various diffuse cosmic sources are then made, and the reasons for significant differences with previous estimates are discussed. Small predicted event rates for a DUMAND (deep underwater muon and neutrino detector) type detection system, combined with a possible significant flux of prompt neutrinos from the atmosphere above 50 TeV, may make the study of diffuse extraterrestrial neutrinos more difficult than previously thought.

  5. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Anti?i?, T.; Anzalone, A.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Bäuml, J.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Bohá?ová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Cheng, S. H.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; del Peral, L.; Deligny, O.; Dembinski, H.; Dhital, N.; Di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Fajardo Tapia, I.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filip?i?, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gaior, R.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Guzman, A.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Hollon, N.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jarne, C.; Jiraskova, S.; Kadija, K.; Kampert, K. H.; Karhan, P.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Aüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Maccarone, M. C.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, J.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martinez, H.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mi?anovi?, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Nhung, P. T.; Niemietz, L.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; P?kala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.

    2011-06-01

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 × 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

  6. North-south asymmetry for high-energy cosmic-ray electrons measured with the PAMELA experiment

    SciTech Connect

    Karelin, A. V., E-mail: karelin@hotbox.ru ['MEPhI' National Research Nuclear University (Russian Federation); Adriani, O. [Structure of Florence and Physics Department of University of Florence, INFN (Italy)] [Structure of Florence and Physics Department of University of Florence, INFN (Italy); Barbarino, G. C. [Structure of Naples and Physics Department of University of Naples, INFN (Italy)] [Structure of Naples and Physics Department of University of Naples, INFN (Italy); Bazilevskaya, G. A. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)] [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Bellotti, R. [Structure of Bari and Physics Department of University of Bari, INFN (Italy)] [Structure of Bari and Physics Department of University of Bari, INFN (Italy); Boezio, M. [Structure of Trieste and Physics Department of University of Trieste, INFN (Italy)] [Structure of Trieste and Physics Department of University of Trieste, INFN (Italy); Bogomolov, E. A. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)] [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Bonechi, L.; Bongi, M. [Structure of Florence and Physics Department of University of Florence, INFN (Italy)] [Structure of Florence and Physics Department of University of Florence, INFN (Italy); Bonvicini, V. [Structure of Trieste and Physics Department of University of Trieste, INFN (Italy)] [Structure of Trieste and Physics Department of University of Trieste, INFN (Italy); Bottai, S. [Structure of Florence and Physics Department of University of Florence, INFN (Italy)] [Structure of Florence and Physics Department of University of Florence, INFN (Italy); Bruno, A. [Structure of Bari and Physics Department of University of Bari, INFN (Italy)] [Structure of Bari and Physics Department of University of Bari, INFN (Italy); Vacchi, A. [Structure of Trieste and Physics Department of University of Trieste, INFN (Italy)] [Structure of Trieste and Physics Department of University of Trieste, INFN (Italy); Vannuccini, E. [Structure of Florence and Physics Department of University of Florence, INFN (Italy)] [Structure of Florence and Physics Department of University of Florence, INFN (Italy); Vasilyev, G. I. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)] [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Voronov, S. A.; Galper, A. M.; Danilchenko, I. A. ['MEPhI' National Research Nuclear University (Russian Federation)] ['MEPhI' National Research Nuclear University (Russian Federation); Donato, C. De; Santis, C. De [Structure of Rome Tor Vergata and Physics Department of University of Rome Tor Vergata, INFN (Italy)] [Structure of Rome Tor Vergata and Physics Department of University of Rome Tor Vergata, INFN (Italy); and others

    2013-08-15

    The north-south asymmetry for cosmic-ray particles was measured with one instrument of the PAMELA satellite-borne experiment in the period June 2006-May 2009. The analysis has been performed by two independent methods: by comparing the count rates in regions with identical geomagnetic conditions and by comparing the experimental distribution of particle directions with the simulated distribution that would be in the case of an isotropic particle flux. The dependences of the asymmetry on energy release in the PAMELA calorimeter and on time have been constructed. The asymmetry (N{sub n} - N{sub s})/(N{sub n} + N{sub s}) is 0.06 {+-} 0.004 at the threshold energy release in the calorimeter and gradually decreases with increasing energy release. The observed effect is shown to be produced by electrons in the energy range 10-100 GeV.

  7. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

    DOE PAGESBeta

    Abreu, P; Aglietta, M; Ahn, E J; Albuquerque, I F.M.; Allard, D; Allekotte, I; Allen, J; Allison, P; Alvarez Castillo, J; Alvarez-Muniz, J; et al

    2011-06-17

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrativemore »values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.« less

  8. Constraints on dark matter models from a Fermi LAT search for high-energy cosmic-ray electrons from the Sun

    NASA Astrophysics Data System (ADS)

    Ajello, M.; Atwood, W. B.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bottacini, E.; Bouvier, A.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Cecchi, C.; Charles, E.; Chekhtman, A.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Cutini, S.; de Angelis, A.; de Palma, F.; Dermer, C. D.; Digel, S. W.; Do Couto E Silva, E.; Drell, P. S.; Favuzzi, C.; Fegan, S. J.; Focke, W. B.; Fukazawa, Y.; Fusco, P.; Gargano, F.; Gehrels, N.; Germani, S.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I. A.; Guiriec, S.; Gustafsson, M.; Hadasch, D.; Iafrate, G.; Jóhannesson, G.; Johnson, A. S.; Kamae, T.; Katagiri, H.; Kataoka, J.; Kuss, M.; Latronico, L.; Lionetto, A. M.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mizuno, T.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Naumann-Godo, M.; Norris, J. P.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orlando, E.; Ormes, J. F.; Ozaki, M.; Paneque, D.; Panetta, J. H.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Ritz, S.; Schalk, T. L.; Sgrò, C.; Siegal-Gaskins, J.; Siskind, E. J.; Smith, P. D.; Spandre, G.; Spinelli, P.; Suson, D. J.; Takahashi, H.; Tanaka, T.; Thayer, J. G.; Thayer, J. B.; Tibaldo, L.; Tosti, G.; Troja, E.; Usher, T. L.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vilchez, N.; Waite, A. P.; Wang, P.; Winer, B. L.; Wood, K. S.; Yang, Z.; Zimmer, S.

    2011-08-01

    During its first year of data taking, the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope has collected a large sample of high-energy cosmic-ray electrons and positrons (CREs). We present the results of a directional analysis of the CRE events, in which we searched for a flux excess correlated with the direction of the Sun. Two different and complementary analysis approaches were implemented, and neither yielded evidence of a significant CRE flux excess from the Sun. We derive upper limits on the CRE flux from the Sun’s direction, and use these bounds to constrain two classes of dark matter models which predict a solar CRE flux: (1) models in which dark matter annihilates to CREs via a light intermediate state, and (2) inelastic dark matter models in which dark matter annihilates to CREs.

  9. Proc. 11th Int. Conf. on Cosmic Rays, Budapest 1969 ZENITH-ANGLE DISTRIBUTION OF ULTRA-HIGH ENERGY

    E-print Network

    -HIGH ENERGY MUONS* J. W. KEUFFEL, J. L. OSBORNE, G. L. BOLINGBROKE, G. W. MASON. M. O. LARSON, G. H. LOWE, J-angle distribution of ultra-high energy muons is of great importance because, in the conventional picture of high-energy, for muon energies E > B - a condition which is well satisfied at our depths for muons of pion parentage (B

  10. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

    SciTech Connect

    Abreu, P [Lisbon, IST; Aglietta, M [IFSI, Turin; Ahn, E J [Fermilab; Albuquerque, I F.M. [Sao Paulo U.; Allard, D [APC, Paris; Allekotte, I [Centro Atomico Bariloche; Allen, J [New York U.; Allison, P [Ohio State U.; Alvarez Castillo, J [Mexico U., ICN; Alvarez-Muniz, J [Santiago de Compostela U.; Ambrosio, M [Napoli Seconda U.; INFN, Naples; Nijmegen U., IMAPP

    2011-06-17

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

  11. A search for anisotropy in the arrival directions of ultra-high-energy cosmic rays observed by the High Resolution Fly's Eye detector

    NASA Astrophysics Data System (ADS)

    Stokes, Benjamin Taylor

    2006-06-01

    Although the existence of cosmic rays with energies extending well above 10^19 eV has been confirmed, their origin remains one of the most important questions in astro-particle physics today. The High Resolution Fly's Eye Detector (HiRes) detects Ultra High Energy Cosmic Rays (UHECRs) by employing the air- fluorescence technique to observe Extensive Air Showers (EAS) in the atmosphere over Dugway, Utah. It has been collecting data since May 1997 during which time over 1500 events with energies greater than 10 18.5 eV have been observed in monocular mode. These events are characterized by arrival directions with asymmetric uncertainties, which are explored in detail for this study. Multiple methods are developed and utilized to search for anisotropies in the arrival directions. A primary emphasis is placed upon previous reported observations that suggested small-scale clustering and global dipole biases. Additionally a new method for searching for anisotropies is explored. While all conclusions are statistically limited in their applicability, the sensitivities are shown to be compatible with prior experiments. However, all evidence to date on the arrival directions of the UHECRs observed by HiRes in monocular mode is consistent with an isotropic distribution.

  12. Study of Ultra-High Energy Cosmic Ray Composition Using Telescope Array's Middle Drum Detector and Surface Array in Hybrid Mode

    E-print Network

    Abbasi, R U; Abu-Zayyad, T; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A; Cady, R; Chae, M J; Cheon, B G; Chiba, J; Chikawa, M; Cho, W R; Fujii, T; Fukushima, M; Goto, T; Hanlon, W; Hayashi, Y; Hayashida, N; Hibino, K; Honda, K; Ikeda, D; Inoue, N; Ishii, T; Ishimori, R; Ito, H; Ivanov, D; Jui, C C H; Kadota, K; Kakimoto, F; Kalashev, O; Kasahara, K; Kawai, H; Kawakami, S; Kawana, S; Kawata, K; Kido, E; Kim, H B; Kim, J H; Kitamura, S; Kitamura, Y; Kuzmin, V; Kwon, Y J; Lan, J; Lim, S I; Lundquist, J P; Machida, K; Martens, K; Matsuda, T; Matsuyama, T; Matthews, J N; Minamino, M; Mukai, Y; Myers, I; Nagasawa, K; Nagataki, S; Nakamura, T; Nonaka, T; Nozato, A; Ogio, S; Ogura, J; Ohnishi, M; Ohoka, H; Oki, K; Okuda, T; Ono, M; Oshima, A; Ozawa, S; Park, I H; Pshirkov, M S; Rodriguez, D C; Rubtsov, G; Ryu, D; Sagawa, H; Sakurai, N; Sampson, A L; Scott, L M; Shah, P D; Shibata, F; Shibata, T; Shimodaira, H; Shin, B K; Shin, H S; Smith, J D; Sokolsky, P; Springer, R W; Stokes, B T; Stratton, S R; Stroman, T; Suzawa, T; Takamura, M; Takeda, M; Takeishi, R; Taketa, A; Takita, M; Tameda, Y; Tanaka, H; Tanaka, K; Tanaka, M; Thomas, S B; Thomson, G B; Tinyakov, P; Tkachev, I; Tokuno, H; Tomida, T; Troitsky, S; Tsunesada, Y; Tsutsumi, K; Uchihori, Y; Udo, S; Urban, F; Vasiloff, G; Wong, T; Yamane, R; Yamaoka, H; Yamazaki, K; Yang, J; Yashiro, K; Yoneda, Y; Yoshida, S; Yoshiia, H; Zollinger, R; Zundel, Z

    2014-01-01

    Previous measurements of the composition of Ultra-High energy Cosmic Rays (UHECRs) made by the High Resolution Fly's Eye (HiRes) and Pierre Auger Observatory (PAO) are seemingly contradictory but utilize different detection methods, as HiRes was a stereo detector and PAO is a hybrid detector. The five year Telescope Array (TA) Middle Drum hybrid composition measurement is similar in methodology to PAO, and good agreement is evident between data and a light, largely protonic composition using simulations from a variety of hadronic models for the comparison of both elongation rate and shower fluctuations. This is in good agreement with the HiRes results. This analysis is presented using two methods: data cuts using simple geometrical variables and a new pattern recognition technique.

  13. A 100,000 pulse height analyzer for use in High Energy Cosmic Ray Experiments (HECRE) on high altitude balloon flights

    NASA Technical Reports Server (NTRS)

    Cancro, C. A.; Garrahan, N. M.; Mcgowan, R. G.

    1971-01-01

    A description is given of a wide dynamic range pulse height analyzer system developed for use on High Energy Cosmic Ray Experiment (HECRE) Balloon Flights. A wide dynamic range of 100,000 is obtained by extending the range of a basic 1024 channel analyzer through the use of multiple ranges and range selection. The system described here contains four 100,000 pulse height analyzers. Each 100,000 pulse height analyzer consists of a group of cordwood welded modules mounted and interconnected on a printed circuit card. Four of these card assemblies, the required clock drive circuitry (discrete components mounted and interconnected on a separate card) and three input-output connectors are interconnected and mounted on the system board.

  14. Science with the new generation high energy gamma- ray experiments

    Microsoft Academic Search

    M. Alvarez; D. D'Armiento; G. Agnetta; A. Alberdi; A. Antonelli; A. Argan; P. Assis; E. A. Baltz; C. Bambi; G. Barbiellini; H. Bartko; M. Basset; D. Bastieri; P. Belli; G. Benford; L. Bergstrom; R. Bernabei; G. Bertone; A. Biland; B. Biondo; F. Bocchino; E. Branchini; M. Brigida; T. Bringmann; P. Brogueira; A. Bulgarelli; J. A. Caballero; G. A. Caliandro; P. Camarri; F. Cappella; P. Caraveo; R. Carbone; M. Carvajal; S. Casanova; A. J. Castro-Tirado; O. Catalano; R. Catena; F. Celi; A. Celotti; R. Cerulli; A. Chen; R. Clay; V. Cocco; J. Conrad; E. Costa; A. Cuoco; G. Cusumano; C. J. Dai; B. Dawson; B. De Lotto; G. De Paris; A. de Ugarte Postigo; E. Del Monte; C. Delgado; A. Di Ciaccio; G. Di Cocco; S. Di Falco; G. Di Persio; B. L. Dingus; A. Dominguez; F. Donato; I. Donnarumma; M. Doro; J. Edsjo; J. M. Espino Navas; M. C. Espirito Santo; Y. Evangelista; C. Evoli; D. Fargion; C. Favuzzi; M. Feroci; M. Fiorini; L. Foggetta; N. Fornengo; T. Froysland; M. Frutti; F. Fuschino; J. L. Gomez; M. Gomez; D. Gaggero; N. Galante; M. I. Gallardo; M. Galli; J. E. Garcia; M. Garczarczyk; F. Gargano; M. Gaug; F. Gianotti; S. Giarrusso; B. Giebels; N. Giglietto; P. Giommi; F. Giordano; A. Giuliani; J. Glicenstein; P. Goncalves; D. Grasso; M. Guerriero; H. L. He; A. Incicchitti; J. Kirk; H. H. Kuang; A. La Barbera; G. La Rosa; C. Labanti; G. Lamanna; I. Lapshov; F. Lazzarotto; S. Liberati; F. Liello; P. Lipari; F. Longo; F. Loparco; M. Lozano; P. G. Lucentini De Sanctis; J. M. Ma; M. C. Maccarone; L. Maccione; V. Malvezzi; A. Mangano; M. Mariotti; M. Marisaldi; I. Martel; A. Masiero; E. Massaro; M. Mastropietro; E. Mattaini; F. Mauri; M. N. Mazziotta; S. Mereghetti; T. Mineo; S. Mizobuchi; A. Moiseev; M. Moles; C. Monte; F. Montecchia; E. Morelli; A. Morselli; I. Moskalenko; F. Nozzoli; J. F. Ormes; M. A. Peres-Torres; L. Pacciani; A. Pellizzoni; F. Perez-Bernal; F. Perotti; P. Picozza; L. Pieri; M. Pietroni; M. Pimenta; A. Pina; C. Pittori; C. Pontoni; G. Porrovecchio; F. Prada; M. Prest; D. Prosperi; R. Protheroe; G. Pucella; J. M. Quesada; J. M. Quintana; J. R. Quintero; S. Raino; M. Rapisarda; M. Rissi; J. Rodriguez; E. Rossi; G. Rowell; A. Rubini; F. Russo; M. Sanchez-Conde; B. Sacco; V. Scapin; M. Schelke; A. Segreto; A. Sellerholm; X. D. Sheng; A. Smith; P. Soffitta; R. Sparvoli; P. Spinelli; V. Stamatescu; L. S. Stark; M. Tavani; G. Thornton; L. G. Titarchuk; B. Tome; A. Traci; M. Trifoglio; A. Trois; P. Vallania; E. Vallazza; S. Vercellone; S. Vernetto; V. Vitale; N. Wild; Z. P. Ye; A. Zambra; F. Zandanel; D. Zanello

    2007-01-01

    This Conference is the fifth of a series of Workshops on High Energy Gamma- ray Experiments, following the Conferences held in Perugia 2003, Bari 2004, Cividale del Friuli 2005, Elba Island 2006. This year the focus was on the use of gamma-ray to study the Dark Matter component of the Universe, the origin and propagation of Cosmic Rays, Extra Large

  15. The Origin of Cosmic Rays

    ScienceCinema

    Pasquale Blasi

    2010-01-08

    Cosmic Rays reach the Earth from space with energies of up to more than 1020 eV, carrying information on the most powerful particle accelerators that Nature has been able to assemble. Understanding where and how cosmic rays originate has required almost one century of investigations, and, although the last word is not written yet, recent observations and theory seem now to fit together to provide us with a global picture of the origin of cosmic rays of unprecedented clarity. Here we will describe what we learned from recent observations of astrophysical sources (such as supernova remnants and active galaxies) and we will illustrate what these observations tell us about the physics of particle acceleration and transport. We will also discuss the ?end? of the Galactic cosmic ray spectrum, which bridges out attention towards the so called ultra high energy cosmic rays (UHECRs). At ~1020 eV the gyration scale of cosmic rays in cosmic magnetic fields becomes large enough to allow us to point back to their sources, thereby allowing us to perform ?cosmic ray astronomy?, as confirmed by the recent results obtained with the Pierre Auger Observatory. We will discuss the implications of these observations for the understanding of UHECRs, as well as some questions which will likely remain unanswered and will be the target of the next generation of cosmic ray experiments.

  16. Ultrahigh Energy Cosmic Rays Detection

    E-print Network

    Carla Aramo

    2005-09-06

    The paper describes methods used for the detection of cosmic rays with energies above 10^18 eV (UHECR, UltraHigh Energy Cosmic Rays). It had been anticipated there would be a cutoff in the energy spectrum of primary cosmic rays around 3 10^19 eV induced by their interaction with the 2.7 K primordial photons. This has become known as the GZK cutoff. However, several showers have been detected with estimated primary energy exceeding this limit.

  17. Reference Radiation for Cosmic Rays in RBE Research 

    E-print Network

    Feng, Shaoyong

    2011-10-21

    When astronauts travel in space, they are exposed to high energy cosmic radiations. The cosmic ray spectrum contains very high energy particles, generally up to several GeV per nucleon. Currently NASA is funding research on the effects...

  18. Reference Radiation for Cosmic Rays in RBE Research

    E-print Network

    Feng, Shaoyong

    2011-10-21

    When astronauts travel in space, they are exposed to high energy cosmic radiations. The cosmic ray spectrum contains very high energy particles, generally up to several GeV per nucleon. Currently NASA is funding research on the effects...

  19. X-Rays from NGC 3256: High-Energy Emission in Starburst Galaxies and Their Contribution to the Cosmic X-Ray Background

    NASA Astrophysics Data System (ADS)

    Moran, Edward C.; Lehnert, Matthew D.; Helfand, David J.

    1999-12-01

    The infrared-luminous galaxy NGC 3256 is a classic example of a merger-induced nuclear starburst system. We find here that it is the most X-ray-luminous star-forming galaxy yet detected (L0.5-10keV=1.6×1042 ergs s-1). Long-slit optical spectroscopy and a deep, high-resolution ROSAT X-ray image show that the starburst is driving a ``superwind'' which accounts for ~20% of the observed soft X-ray emission. Analysis of X-ray spectral data from ASCA indicates this gas has a characteristic temperature of kT~0.3 keV. Our model for the broadband X-ray emission of NGC 3256 contains two additional components: a warm thermal plasma (kT~0.8 keV) associated with the central starburst, and a hard power-law component with an energy index of ?X~0.7. We discuss the energy budget for the two thermal plasmas and find that the input of mechanical energy from the starburst is more than sufficient to sustain the observed level of emission. We also examine possible origins for the power-law component, concluding that neither a buried AGN nor the expected population of high-mass X-ray binaries can account for this emission. Inverse Compton scattering, involving the galaxy's copious flux of infrared photons and the relativistic electrons produced by supernovae, is likely to make a substantial contribution to the hard X-ray flux. Such a model is consistent with the observed radio and IR fluxes and the radio and X-ray spectral indices. We explore the role of X-ray-luminous starbursts in the production of the cosmic X-ray background radiation. The number counts and spectral index distribution of the faint radio source population, thought to be dominated by star-forming galaxies, suggest that a significant fraction of the hard X-ray background could arise from starbursts at moderate redshift.

  20. A Simplified Model for the Acceleration of Cosmic Ray Particles

    ERIC Educational Resources Information Center

    Gron, Oyvind

    2010-01-01

    Two important questions concerning cosmic rays are: Why are electrons in the cosmic rays less efficiently accelerated than nuclei? How are particles accelerated to great energies in ultra-high energy cosmic rays? In order to answer these questions we construct a simple model of the acceleration of a charged particle in the cosmic ray. It is not…

  1. Cosmic rays: the highest-energy messengers.

    PubMed

    Olinto, Angela V

    2007-01-01

    The origin of the most energetic particles ever observed, cosmic rays, will begin to be revealed in the next few years. Newly constructed ultrahigh-energy cosmic ray observatories together with high-energy gamma-ray and neutrino observatories are well positioned to unveil this mystery before the centenary of their discovery in 2012. Cosmic ray sources are likely to involve the most energetic phenomena ever witnessed in the universe. PMID:17204641

  2. A Search for Correlation of Ultra-High Energy Cosmic Rays with IRAS-PSCz and 2MASS-6dF Galaxies

    E-print Network

    Foteini Oikonomou; Amy Connolly; Filipe B. Abdalla; Ofer Lahav; Shaun A. Thomas; David Waters; Eli Waxman

    2013-05-18

    We study the arrival directions of 69 ultra-high energy cosmic rays (UHECRs) observed at the Pierre Auger Observatory (PAO) with energies exceeding 55 EeV. We investigate whether the UHECRs exhibit the anisotropy signal expected if the primary particles are protons that originate in galaxies in the local universe, or in sources correlated with these galaxies. We cross-correlate the UHECR arrival directions with the positions of IRAS-PSCz and 2MASS-6dF galaxies taking into account particle energy losses during propagation. This is the first time that the 6dF survey is used in a search for the sources of UHECRs and the first time that the PSCz survey is used with the full 69 PAO events. The observed cross-correlation signal is larger for the PAO UHECRs than for 94% (98%) of realisations from an isotropic distribution when cross-correlated with the PSCz (6dF). On the other hand the observed cross-correlation signal is lower than that expected from 85% of realisations, had the UHECRs originated in galaxies in either survey. The observed cross-correlation signal does exceed that expected by 50% of the realisations if the UHECRs are randomly deflected by intervening magnetic fields by 5 degrees or more. We propose a new method of analysing the expected anisotropy signal, by dividing the predicted UHECR source distribution into equal predicted flux radial shells, which can help localise and constrain the properties of UHECR sources. We find that the 69 PAO events are consistent with isotropy in the nearest of three shells we define, whereas there is weak evidence for correlation with the predicted source distribution in the two more distant shells in which the galaxy distribution is less anisotropic.

  3. A search for correlation of ultra-high energy cosmic rays with IRAS-PSCz and 2MASS-6dF galaxies

    SciTech Connect

    Oikonomou, Foteini; Abdalla, Filipe B.; Lahav, Ofer; Thomas, Shaun A. [Astrophysics Group, Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Connolly, Amy [Department of Physics and CCAPP, The Ohio State University, 191 West Woodruff Avenue, Colombus, Ohio 43210 (United States); Waters, David [High Energy Physics Group, Department of Physics and Astronomy, University College London (United Kingdom); Waxman, Eli, E-mail: fotini@star.ucl.ac.uk, E-mail: connolly@physics.osu.edu, E-mail: fba@star.ucl.ac.uk, E-mail: o.lahav@ucl.ac.uk, E-mail: sat@star.ucl.ac.uk, E-mail: d.waters@ucl.ac.uk, E-mail: eli.waxman@weizmann.ac.il [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100 (Israel)

    2013-05-01

    We study the arrival directions of 69 ultra-high energy cosmic rays (UHECRs) observed at the Pierre Auger Observatory (PAO) with energies exceeding 55 EeV. We investigate whether the UHECRs exhibit the anisotropy signal expected if the primary particles are protons that originate in galaxies in the local universe, or in sources correlated with these galaxies. We cross-correlate the UHECR arrival directions with the positions of IRAS-PSCz and 2MASS-6dF galaxies taking into account particle energy losses during propagation. This is the first time that the 6dF survey is used in a search for the sources of UHECRs and the first time that the PSCz survey is used with the full 69 PAO events. The observed cross-correlation signal is larger for the PAO UHECRs than for 94% (98%) of realisations from an isotropic distribution when cross-correlated with the PSCz (6dF). On the other hand the observed cross-correlation signal is lower than that expected from ?>85% of realisations, had the UHECRs originated in galaxies in either survey. The observed cross-correlation signal does exceed that expected by 50% of the realisations if the UHECRs are randomly deflected by intervening magnetic fields by 5° or more. We propose a new method of analysing the expected anisotropy signal, by dividing the predicted UHECR source distribution into equal predicted flux radial shells, which can help localise and constrain the properties of UHECR sources. We find that the 69 PAO events are consistent with isotropy in the nearest of three shells we define, whereas there is weak evidence for correlation with the predicted source distribution in the two more distant shells in which the galaxy distribution is less anisotropic.

  4. The Heliosphere and Galactic Cosmic Rays - Duration: 39 seconds.

    NASA Video Gallery

    The heliosphere deflects galactic cosmic rays from entering the system. Galactic cosmic rays are a very high energy form of particle radiation that are extremely difficult to shield against and are...

  5. Science with the new generation high energy gamma- ray experiments

    E-print Network

    M. Alvarez; D. D'Armiento; G. Agnetta; A. Alberdi; A. Antonelli; A. Argan; P. Assis; E. A. Baltz; C. Bambi; G. Barbiellini; H. Bartko; M. Basset; D. Bastieri; P. Belli; G. Benford; L. Bergstrom; R. Bernabei; G. Bertone; A. Biland; B. Biondo; F. Bocchino; E. Branchini; M. Brigida; T. Bringmann; P. Brogueira; A. Bulgarelli; J. A. Caballero; G. A. Caliandro; P. Camarri; F. Cappella; P. Caraveo; R. Carbone; M. Carvajal; S. Casanova; A. J. Castro-Tirado; O. Catalano; R. Catena; F. Celi; A. Celotti; R. Cerulli; A. Chen; R. Clay; V. Cocco; J. Conrad; E. Costa; A. Cuoco; G. Cusumano; C. J. Dai; B. Dawson; B. De Lotto; G. De Paris; A. de Ugarte Postigo; E. Del Monte; C. Delgado; A. Di Ciaccio; G. Di Cocco; S. Di Falco; G. Di Persio; B. L. Dingus; A. Dominguez; F. Donato; I. Donnarumma; M. Doro; J. Edsjo; J. M. Espino Navas; M. C. Espirito Santo; Y. Evangelista; C. Evoli; D. Fargion; C. Favuzzi; M. Feroci; M. Fiorini; L. Foggetta; N. Fornengo; T. Froysland; M. Frutti; F. Fuschino; J. L. Gomez; M. Gomez; D. Gaggero; N. Galante; M. I. Gallardo; M. Galli; J. E. Garcia; M. Garczarczyk; F. Gargano; M. Gaug; F. Gianotti; S. Giarrusso; B. Giebels; N. Giglietto; P. Giommi; F. Giordano; A. Giuliani; J. Glicenstein; P. Goncalves; D. Grasso; M. Guerriero; H. L. He; A. Incicchitti; J. Kirk; H. H. Kuang; A. La Barbera; G. La Rosa; C. Labanti; G. Lamanna; I. Lapshov; F. Lazzarotto; S. Liberati; F. Liello; P. Lipari; F. Longo; F. Loparco; M. Lozano; P. G. Lucentini De Sanctis; J. M. Ma; M. C. Maccarone; L. Maccione; V. Malvezzi; A. Mangano; M. Mariotti; M. Marisaldi; I. Martel; A. Masiero; E. Massaro; M. Mastropietro; E. Mattaini; F. Mauri; M. N. Mazziotta; S. Mereghetti; T. Mineo; S. Mizobuchi; A. Moiseev; M. Moles; C. Monte; F. Montecchia; E. Morelli; A. Morselli; I. Moskalenko; F. Nozzoli; J. F. Ormes; M. A. Peres-Torres; L. Pacciani; A. Pellizzoni; F. Perez-Bernal; F. Perotti; P. Picozza; L. Pieri; M. Pietroni; M. Pimenta; A. Pina; C. Pittori; C. Pontoni; G. Porrovecchio; F. Prada; M. Prest; D. Prosperi; R. Protheroe; G. Pucella; J. M. Quesada; J. M. Quintana; J. R. Quintero; S. Raino; M. Rapisarda; M. Rissi; J. Rodriguez; E. Rossi; G. Rowell; A. Rubini; F. Russo; M. Sanchez-Conde; B. Sacco; V. Scapin; M. Schelke; A. Segreto; A. Sellerholm; X. D. Sheng; A. Smith; P. Soffitta; R. Sparvoli; P. Spinelli; V. Stamatescu; L. S. Stark; M. Tavani; G. Thornton; L. G. Titarchuk; B. Tome; A. Traci; M. Trifoglio; A. Trois; P. Vallania; E. Vallazza; S. Vercellone; S. Vernetto; V. Vitale; N. Wild; Z. P. Ye; A. Zambra; F. Zandanel; D. Zanello

    2007-12-04

    This Conference is the fifth of a series of Workshops on High Energy Gamma- ray Experiments, following the Conferences held in Perugia 2003, Bari 2004, Cividale del Friuli 2005, Elba Island 2006. This year the focus was on the use of gamma-ray to study the Dark Matter component of the Universe, the origin and propagation of Cosmic Rays, Extra Large Spatial Dimensions and Tests of Lorentz Invariance.

  6. Science with the new generation high energy gamma- ray experiments

    E-print Network

    Alvarez, M; Agnetta, G; Alberdi, A; Antonelli, A; Argan, A; Assis, P; Baltz, E A; Bambi, C; Barbiellini, G; Bartko, H; Basset, M; Bastieri, D; Belli, P; Benford, G; Bergström, L; Bernabei, R; Bertone, G; Biland, A; Biondo, B; Bocchino, F; Branchini, E; Brigida, M; Bringmann, T; Brogueira, P; Bulgarelli, A; Caballero, J A; Caliandro, G A; Camarri, P; Cappella, F; Caraveo, P; Carbone, R; Carvajal, M; Casanova, S; Castro-Tirado, A J; Catalano, O; Catena, R; Celi, F; Celotti, A; Cerulli, R; Chen, A; Clay, R; Cocco, V; Conrad, J; Costa, E; Cuoco, A; Cusumano, G; Dai, C J; Dawson, B; De Lotto, B; De Paris, G; Postigo, A de Ugarte; Del Monte, E; Delgado, C; Di Ciaccio, A; Di Cocco, G; Di Falco, S; Di Persio, G; Dingus, B L; Dominguez, A; Donato, F; Donnarumma, I; Doro, M; Edsjö, J; Navas, J M Espino; Santo, M C Espirito; Evangelista, Y; Evoli, C; Fargion, D; Favuzzi, C; Feroci, M; Fiorini, M; Foggetta, L; Fornengo, N; Froysland, T; Frutti, M; Fuschino, F; Gómez, J L; Gómez, M; Gaggero, D; Galante, N; Gallardo, M I; Galli, M; García, J E; Garczarczyk, M; Gargano, F; Gaug, M; Gianotti, F; Giarrusso, S; Giebels, B; Giglietto, N; Giommi, P; Giordano, F; Giuliani, A; Glicenstein, J; Gonçalves, P; Grasso, D; Guerriero, M; He, H L; Incicchitti, A; Kirk, J; Kuang, H H; La Barbera, A; La Rosa, G; Labanti, C; Lamanna, G; Lapshov, I; Lazzarotto, F; Liberati, S; Liello, F; Lipari, P; Longo, F; Loparco, F; Lozano, M; De Sanctis, P G Lucentini; Ma, J M; Maccarone, M C; Maccione, L; Malvezzi, V; Mangano, A; Mariotti, M; Marisaldi, M; Martel, I; Masiero, A; Massaro, E; Mastropietro, M; Mattaini, E; Mauri, F; Mazziotta, M N; Mereghetti, S; Mineo, T; Mizobuchi, S; Moiseev, A; Moles, M; Monte, C; Montecchia, F; Morelli, E; Morselli, A; Moskalenko, I; Nozzoli, F; Ormes, J F; Peres-Torres, M A; Pacciani, L; Pellizzoni, A; Pérez-Bernal, F; Perotti, F; Picozza, P; Pieri, L; Pietroni, M; Pimenta, M; Pina, A; Pittori, C; Pontoni, C; Porrovecchio, G; Prada, F; Prest, M; Prosperi, D; Protheroe, R; Pucella, G; Quesada, J M; Quintana, J M; Quintero, J R; Rainó, S; Rapisarda, M; Rissi, M; Rodríguez, J; Rossi, E; Rowell, G; Rubini, A; Russo, F; Sanchez-Conde, M; Sacco, B; Scapin, V; Schelke, M; Segreto, A; Sellerholm, A; Sheng, X D; Smith, A; Soffitta, P; Sparvoli, R; Spinelli, P; Stamatescu, V; Stark, L S; Tavani, M; Thornton, G; Titarchuk, L G; Tomé, B; Traci, A; Trifoglio, M; Trois, A; Vallania, P; Vallazza, E; Vercellone, S; Vernetto, S; Vitale, V; Wild, N; Ye, Z P; Zambra, A; Zandanel, F; Zanello, D

    2007-01-01

    This Conference is the fifth of a series of Workshops on High Energy Gamma- ray Experiments, following the Conferences held in Perugia 2003, Bari 2004, Cividale del Friuli 2005, Elba Island 2006. This year the focus was on the use of gamma-ray to study the Dark Matter component of the Universe, the origin and propagation of Cosmic Rays, Extra Large Spatial Dimensions and Tests of Lorentz Invariance.

  7. Cosmic ray modulation by interplanetary disturbances

    Microsoft Academic Search

    Carlos Roberto Braga; Alisson Dal Lago; Nelson Jorge Schuch; Marlos da Silva; Ezequiel Echer; Walter Demítrio Gonzalez Alarcon; Kazuoki Munakata; Takao Kuwabara; Chihiro Kato; John W. Bieber

    2010-01-01

    Interplanetary disturbances such as ICMEs (Interplanetary Coronal Mass Ejections) and CIRs (Corotating Interaction Regions), modulate high-energy cosmic rays reaching the Earth. Prior to the arrival of the disturbances at the Earth, ground based high-energy muon detectors can detect precursory effects in cosmic-ray anisotropy, such as precursory deficit and\\/or excess of intensity along the sunward IMF (Interplanetary Magnetic Field) direction. With

  8. The NuSTAR Extragalactic Survey: A First Sensitive Look at the High-Energy Cosmic X-Ray Background Population

    NASA Technical Reports Server (NTRS)

    Alexander, D. M.; Stern, D.; DelMoro, A.; Lansbury, G. B.; Assef, R. J.; Aird, J.; Ajello, M.; Ballantyne, D. R.; Bauer, F. E.; Boggs, S. E.; Brandt, W. N.; Christensen, F. E.; Civano, F.; Cosmastri, A.; Craig, W. W.; Elvis, M.; Grefenstette, B. W.; Hailey, C. J.; Harrison, F. A.; Hickox, R. C.; Luo, B.; Madsen, K. K.; Alexander, D. M.; Zhang, W. W.; Eisenhardt, P. R. M.

    2013-01-01

    We report on the first 10 identifications of sources serendipitously detected by the Nuclear Spectroscopic Telescope Array (NuSTAR) to provide the first sensitive census of the cosmic X-ray background source population at approximately greater than 10 keV. We find that these NuSTAR-detected sources are approximately 100 times fainter than those previously detected at approximately greater than 10 keV and have a broad range in redshift and luminosity (z = 0.020-2.923 and L(sub 10-40 keV) approximately equals 4 × 10(exp 41) - 5 × 10(exp 45) erg per second; the median redshift and luminosity are z approximately equal to 0.7 and L(sub 10-40 keV) approximately equal to 3 × 10(exp 44) erg per second, respectively. We characterize these sources on the basis of broad-band approximately equal to 0.5 - 32 keV spectroscopy, optical spectroscopy, and broad-band ultraviolet-to-mid-infrared spectral energy distribution analyses. We find that the dominant source population is quasars with L(sub 10-40 keV) greater than 10(exp 44) erg per second, of which approximately 50% are obscured with N(sub H) approximately greater than 10(exp 22) per square centimeters. However, none of the 10 NuSTAR sources are Compton thick (N(sub H) approximately greater than 10(exp 24) per square centimeters) and we place a 90% confidence upper limit on the fraction of Compton-thick quasars (L(sub 10-40 keV) greater than 10(exp 44) erg per second) selected at approximately greater than 10 keV of approximately less than 33% over the redshift range z = 0.5 - 1.1. We jointly fitted the rest-frame approximately equal to 10-40 keV data for all of the non-beamed sources with L(sub 10-40 keV) greater than 10(exp 43) erg per second to constrain the average strength of reflection; we find R less than 1.4 for gamma = 1.8, broadly consistent with that found for local active galactic nuclei (AGNs) observed at approximately greater than 10 keV. We also constrain the host-galaxy masses and find a median stellar mass of approximately 10(exp 11) solar mass, a factor approximately 5 times higher than the median stellar mass of nearby high-energy selected AGNs, which may be at least partially driven by the order of magnitude higher X-ray luminosities of the NuSTAR sources. Within the low source-statistic limitations of our study, our results suggest that the overall properties of the NuSTAR sources are broadly similar to those of nearby high-energy selected AGNs but scaled up in luminosity and mass.

  9. THE NuSTAR EXTRAGALACTIC SURVEY: A FIRST SENSITIVE LOOK AT THE HIGH-ENERGY COSMIC X-RAY BACKGROUND POPULATION

    SciTech Connect

    Alexander, D. M.; Del Moro, A.; Lansbury, G. B.; Aird, J. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Stern, D.; Assef, R. J. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Mail Stop 169-221, Pasadena, CA 91109 (United States); Ajello, M.; Boggs, S. E. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Ballantyne, D. R. [Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Bauer, F. E. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Brandt, W. N. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Christensen, F. E.; Craig, W. W. [DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Civano, F.; Hickox, R. C. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Comastri, A. [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Elvis, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Grefenstette, B. W.; Harrison, F. A. [Cahill Center for Astrophysics, 1216 East California Boulevard, California Institute of Technology, Pasadena, CA 91125 (United States); Hailey, C. J. [Columbia Astrophysics Laboratory, 550 W 120th Street, Columbia University, NY 10027 (United States); and others

    2013-08-20

    We report on the first 10 identifications of sources serendipitously detected by the Nuclear Spectroscopic Telescope Array (NuSTAR) to provide the first sensitive census of the cosmic X-ray background source population at {approx}> 10 keV. We find that these NuSTAR-detected sources are Almost-Equal-To 100 times fainter than those previously detected at {approx}> 10 keV and have a broad range in redshift and luminosity (z = 0.020-2.923 and L{sub 10-40{sub keV}} Almost-Equal-To 4 Multiplication-Sign 10{sup 41}-5 Multiplication-Sign 10{sup 45} erg s{sup -1}); the median redshift and luminosity are z Almost-Equal-To 0.7 and L{sub 10-40{sub keV}} Almost-Equal-To 3 Multiplication-Sign 10{sup 44} erg s{sup -1}, respectively. We characterize these sources on the basis of broad-band Almost-Equal-To 0.5-32 keV spectroscopy, optical spectroscopy, and broad-band ultraviolet-to-mid-infrared spectral energy distribution analyses. We find that the dominant source population is quasars with L{sub 10-40{sub keV}} > 10{sup 44} erg s{sup -1}, of which Almost-Equal-To 50% are obscured with N{sub H} {approx}> 10{sup 22} cm{sup -2}. However, none of the 10 NuSTAR sources are Compton thick (N{sub H} {approx}> 10{sup 24} cm{sup -2}) and we place a 90% confidence upper limit on the fraction of Compton-thick quasars (L{sub 10-40{sub keV}} > 10{sup 44} erg s{sup -1}) selected at {approx}> 10 keV of {approx}< 33% over the redshift range z = 0.5-1.1. We jointly fitted the rest-frame Almost-Equal-To 10-40 keV data for all of the non-beamed sources with L{sub 10-40{sub keV}} > 10{sup 43} erg s{sup -1} to constrain the average strength of reflection; we find R < 1.4 for {Gamma} = 1.8, broadly consistent with that found for local active galactic nuclei (AGNs) observed at {approx}> 10 keV. We also constrain the host-galaxy masses and find a median stellar mass of Almost-Equal-To 10{sup 11} M{sub Sun }, a factor Almost-Equal-To 5 times higher than the median stellar mass of nearby high-energy selected AGNs, which may be at least partially driven by the order of magnitude higher X-ray luminosities of the NuSTAR sources. Within the low source-statistic limitations of our study, our results suggest that the overall properties of the NuSTAR sources are broadly similar to those of nearby high-energy selected AGNs but scaled up in luminosity and mass.

  10. Cosmic x ray physics

    NASA Technical Reports Server (NTRS)

    Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

    1991-01-01

    The annual progress report on Cosmic X Ray Physics for the period 1 Jan. to 31 Dec. 1990 is presented. Topics studied include: soft x ray background, new sounding rocket payload: x ray calorimeter, and theoretical studies.

  11. Cosmic x ray physics

    NASA Technical Reports Server (NTRS)

    Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

    1990-01-01

    The annual progress report on Cosmic X Ray Physics is presented. Topics studied include: the soft x ray background, proportional counter and filter calibrations, the new sounding rocket payload: X Ray Calorimeter, and theoretical studies.

  12. Search for correlations of GRB and cosmic rays

    NASA Astrophysics Data System (ADS)

    J?drzejczak, K.; Kasztelan, M.; Mankiewicz, L.; Molak, M.; Nawrocki, K.; Piotrowski, L. W.; Soko?owski, M.; Szabelska, B.; Szabelski, J.; Wibig, T.; Wolfendale, A. W.; Wrochna, G.

    2007-06-01

    It is possible that violent processes resulting in Gamma Ray Bursts produce also high energy photons and cosmic rays. The possible correlations of very short GRB with, e.g., CMB, cosmic rays is briefly discussed. We have also begun preparation of the experiment correlating in real time data from Maze cosmic ray detector and Pi of the Sky robotic telescope.

  13. Cosmic Ray Astronomy

    E-print Network

    Paul Sommers; Stefan Westerhoff

    2008-02-09

    Cosmic ray astronomy attempts to identify and study the sources of ultrahigh energy cosmic rays. It is unique in its reliance on charged particles as the information carriers. While no discrete source of ultrahigh energy cosmic rays has been identified so far, a new generation of detectors is acquiring the huge exposure that is needed at the highest energies, where deflection by magnetic fields is minimized and the background from distant sources is eliminated by pion photoproduction. In this paper, we summarize the status of cosmic ray astronomy, describing the detectors and the analysis techniques.

  14. Observation of a high-energy cosmic-ray family caused by a Centauro-type nuclear interaction in the joint emulsion chamber experiment at the Pamirs

    Microsoft Academic Search

    A. S. Borisov; K. V. Cherdyntseva; Z. M. Guseva; V. G. Denisova; A. M. Dunaevsky; E. A. Kanevskaya; V. M. Maximenko; R. A. Nam; V. S. Puchkov; S. A. Slavatinsky; M. D. Smirnova; Yu. A. Smorodin; A. V. Uryson; N. G. Zelevinskaya; M. V. Zimin; G. B. Zhdanov; I. A. Mikhailova; R. A. Mukhamedshin; O. E. Nedel'Ko; L. P. Nikolaeva; G. T. Zatsepin; T. P. Amineva; L. T. Baradzei; I. P. Ivanenko; N. P. Iljina; T. V. Lazareva; A. K. Managadze; E. A. Murzina; E. I. Pomelova; E. G. Popova; I. V. Rakobolskaya; T. M. Roganova; N. G. Ryabova; L. G. Sveshnikova; S. D. Cananov; L. Kh. Chadranyan; L. A. Khisanishvilli; M. K. Ladarija; G. G. Leptukh; N. N. Roinishvili; M. S. Svanidze; Z. A. Azimov; I. B. Bobodjanov; N. E. Gubar; Yu. A. Gulov; F. Normuradov; Kh. Shoboronov; S. A. Azimov; D. A. Khalilov; Sh. Myrtojieva; E. G. Mullajanov; A. N. Nosov; Kh. Nuritdinov; T. S. Yuldashbaev; S. E. Bakhtigereev; N. A. Dobrotin; Yu. A. Emelyanov; E. G. Zaitseva; H. Bielawska; H. Bialobrzeska; M. Linke; J. Malinowski; J. Maciaszszyk; A. Krys; A. Tomaszewski; J. Nowicka; Z. Wlodarczyk; J. A. Chinellato; C. Dobrigkeit; J. Bellandi Filho; A. C. Fauth; C. M. G. Lattes; M. J. Menon; C. E. Navia O; K. Sawayanagi; E. H. Shibuya; A. Turtelli; N. M. Amato; N. Arata; F. M. Oliveira Castro; R. H. C. Maldonado; H. Aoki; Y. Fujimoto; Y. Funayama; S. Hasegawa; H. Kumano; H. Semba; M. Tamada; S. Yamashita; T. Shibata; K. Yokoi; A. Ohsawa

    1987-01-01

    An exotic cosmic-ray family event is observed in the large emulsion chamber exposed by the joint at the Pamirs (4360 m above sea level). The family is composed of 120gamma-ray-induced showers and 37 hadron-induced showers with individual visible energy exceeding 1 TeV. The decisive feature of the event is the hadron dominance: SigmaEgamma, SigmaE(gamma)h, , and being

  15. Ultra High Energy Cosmic Radiation: Experimental and Theoretical Status

    E-print Network

    Guenter Sigl

    2006-09-09

    We give a brief overview of the current experimental and theoretical status of cosmic rays above ~10**17 eV. We focus on the role of large scale magnetic fields and on multi-messenger aspects linking charged cosmic ray with secondary gamma-ray and neutrino fluxes.

  16. How Cosmic Rays Affect Humans

    NSDL National Science Digital Library

    2012-08-03

    In this lesson about cosmic rays, students will describe why cosmic rays are dangerous to astronauts. Includes information about student preconceptions. This is activity 3 of 4 from "The Cosmic Ray Telescope for the Effects of Radiation (CRaTER)."

  17. Research Concerning Detection of Cosmic Rays

    Microsoft Academic Search

    Maxwell Grady; John Cunningham; Steve Kuhlmann; Hal Spinka; Dave Underwood; Mark Hammergren

    2010-01-01

    Throughout my academic career at Loyola I have carried out research with the Loyola University Cosmic Event Detection System concerning the possibility of detection of ultra high energy cosmic rays (UHECRs) based on radio meteor scattering methods. This research was furthered through summer internships and research fellowships at Adler Planetarium Chicago and Stony Brook University in New York. At Adler

  18. Pion-to-proton ratio for unaccompanied high-energy cosmic-ray hadrons at mountain altitude using transition-radiation detector

    SciTech Connect

    Ellsworth, R.W.; Ito, A.S.; MacFall, J.R.; Siohan, F.; Streitmatter, R.E.; Tonwar, S.C.; Viswanath, P.R.; Yodh, G.B.

    1983-05-01

    A transition-radiation (TR) detector, consisting of 24 modules of styrofoam radiators and multiwire proportional chambers, and an ionization calorimeter have been used to measure the pion-to-proton ratio among the unaccompanied cosmic-ray hadrons at a mountain altitude of 730 g cm/sup -2/. Using the characteristics of the TR detector obtained from calibrations with particle beams at accelerators, the ..pi../p ratio has been determined for cosmic-ray hadrons as ..pi../p = 0.96 +- 0.15 for hadron energy = 400--800 GeV, and ..pi../p = 0.45 +- 0.25 for energy >800 GeV. Monte Carlo simulations of hadron cascades in the atmosphere using the approximate criterion of unaccompaniment suggest that the observed ..pi../p ratio as well as the previously reported neutral-to-charge ratio can be understood by assuming a value of about (1/3) for the charge exchange in nucleon--air-nucleus inelastic interactions at energies above 400 GeV.

  19. On the determination of the cosmic infrared background radiation from the high-energy spectrum of extragalactic gamma-ray sources

    NASA Technical Reports Server (NTRS)

    Dwek, Eli; Slavin, Jonathan

    1994-01-01

    In a recent paper Stecker, De Jager, & Salamon have suggested using the observed approximately MeV to TeV spectra of extragalactic gamma-ray sources as probes of the local density of the cosmic infrared background radiation (CIBR) and have subsequently claimed a first possible measurement of the CIBR from the analysis of the gamma-ray spectrum of Mrk 421 (De Jager, Stecker, & Salamon). The CIBR from normal galaxies consists of two components: a stellar emission component (CIBRs), and a thermal dust emission component (CIBRd). Photons with energies in the approximately 0.1-2 TeV range interact primarily with the CIBRs, whereas interactions with CIBRd dominate the absorption of photons in the approximately 2-100 TeV energy range. SDS 92 and DSS94 considered only the interaction of the gamma-rays with the dust emission component of the CIBR. We present here an improved analysis of the absorption of extragalactic TeV gamma rays by the CIBR, taking the dual nature of its origin into account. Applying the analysis to the observed gamma-ray spectrum of Mrk 421, a BL Lac object at z = 0.031, we find agreement with DSS94 tentative evidence for absorption by the CINRs. Our analysis therefore limits the detection of the CIBR to the approximately 15-40 micron wavelength regime which, considering the uncertainties in the highest energy (greater than 4 TeV) data and ion the possibility of absorption inside the source, many turn out to be an upper limit on its energy density. At shorter wavelengths (lambda approximately = 1-15 microns), where the gamma-ray interactions are dominated by the CIBRs, our analysis definitely yields only an upper limit on the energy density of the CIBR. In contrast, DSS94 have claimed a possible first measurement of the CIBR over the entire 1-120 micron wavelength region. The upper limit on the CIBRs and tentative detection of the CIBRd are consistent with normal galaxies contributing most of the energy to the CIBR, and constrain the contribution of some exotic sources. With careful modeling of infrared foreground emissions, these constraints on the CIBR are above the values measurable by the DIRBE experiment on board the Cosmic Background Explorer (COBE) satellite.

  20. Cosmic rays and hadronic interactions

    SciTech Connect

    Lipari, Paolo [INFN sez. Roma, and Dipartimento di Fisica, Universita di Roma Sapienza (Italy)

    2013-03-25

    The cosmic ray spectrum extends to particles with energy E{approx} 10{sup 20} eV, that corresponds (assuming that the primary particle is a proton) to a nucleon-nucleon c.m. energy {radical}(s) Asymptotically-Equal-To 430TeV, 50 times higher than the current LHC energy. These very high energy particles can be studied via the observation of the showers they generate in the atmosphere. The interpretation of the data requires therefore the modeling of hadronic interactions in an energy range beyond what can be studied in accelerator experiments. The theoretical problem of estimating the relevant properties of hadronic interactions in this energy range is therefore of central importance for the interpretation of the cosmic ray data. Viceversa, it is in principle possible to obtain information about hadronic interactions from the cosmic ray observations, but this program has to confront the fact that the (freely available) cosmic ray beam has an unknown energy spectrum and an unknown mass composition.

  1. Performance of the SciBar cosmic ray telescope (SciCRT) toward the detection of high-energy solar neutrons in solar cycle 24

    NASA Astrophysics Data System (ADS)

    Sasai, Yoshinori; Nagai, Yuya; Itow, Yoshitaka; Matsubara, Yutaka; Sako, Takashi; Lopez, Diego; Itow, Tsukasa; Munakata, Kazuoki; Kato, Chihiro; Kozai, Masayoshi; Miyazaki, Takahiro; Shibata, Shoichi; Oshima, Akitoshi; Kojima, Hiroshi; Tsuchiya, Harufumi; Watanabe, Kyoko; Koi, Tatsumi; Valdés-Galicia, Jose Francisco; González, Luis Xavier; Ortiz, Ernesto; Musalem, Octavio; Hurtado, Alejandro; Garcia, Rocio; Anzorena, Marcos

    2014-12-01

    We plan to observe solar neutrons at Mt. Sierra Negra (4,600 m above sea level) in Mexico using the SciBar detector. This project is named the SciBar Cosmic Ray Telescope (SciCRT). The main aims of the SciCRT project are to observe solar neutrons to study the mechanism of ion acceleration on the surface of the sun and to monitor the anisotropy of galactic cosmic-ray muons. The SciBar detector, a fully active tracker, is composed of 14,848 scintillator bars, whose dimension is 300 cm × 2.5 cm × 1.3 cm. The structure of the detector enables us to obtain the particle trajectory and its total deposited energy. This information is useful for the energy reconstruction of primary neutrons and particle identification. The total volume of the detector is 3.0 m × 3.0 m × 1.7 m. Since this volume is much larger than the solar neutron telescope (SNT) in Mexico, the detection efficiency of the SciCRT for neutrons is highly enhanced. We performed the calibration of the SciCRT at Instituto Nacional de Astrofisica, Optica y Electronica (INAOE) located at 2,150 m above sea level in Mexico in 2012. We installed the SciCRT at Mt. Sierra Negra in April 2013 and calibrated this detector in May and August 2013. We started continuous observation in March 2014. In this paper, we report the detector performance as a solar neutron telescope and the current status of the SciCRT.

  2. Cosmic ray propagation in the local superbubble

    NASA Technical Reports Server (NTRS)

    Steitmatter, R. E.; Balasubrahmanyan, V. K.; Protheroe, R. J.; Ormes, J. F.

    1984-01-01

    It is suggested that a ring of HI gas lying in the galactic plane is part of a supershell which formed some 3 x to the 7th power years ago. The consequences of a closed magnetic supershell for cosmic ray propagation are examined and it is concluded that there is no evidence which precludes the production and trapping of cosmic rays in such a region. A consequence of superbubble confinement is that the mean age of cosmic rays would be independent of energy. This can be tested by high energy observations of the isotopic composition of Be.

  3. Secondary Antiprotons in Cosmic Rays

    E-print Network

    I. V. Moskalenko; A. W. Strong; J. F. Ormes; M. S. Potgieter; U. W. Langner

    2001-06-27

    High energy collisions of cosmic ray (CR) nuclei with interstellar gas are believed to be the mechanism producing the majority of CR antiprotons. The distinguishing spectral shape with a maximum at 2 GeV and a sharp decrease towards lower energies makes antiprotons a unique probe of the models of particle propagation in the Galaxy and modulation in the heliosphere. Besides, accurate calculation of the secondary antiproton flux provides a ``background'' for searches for exotic signals from the annihilation of supersymmetric particles and primordial black hole evaporation. Recently new data with large statistics on the antiproton flux have become available which allow for such tests to be performed. We use our 3D Galactic cosmic ray propagation code GALPROP to calculate interstellar propagation in several models. For our best model we make predictions of proton and antiproton fluxes near the Earth for different modulation levels and polarity using a steady-state drift model for heliospheric modulation.

  4. Research in particles and fields. [cosmic rays, gamma rays, and cosmic plasma

    NASA Technical Reports Server (NTRS)

    Stone, E. C.; Buffington, A.; Davis, L., Jr.; Prince, T. A.; Vogt, R. E.

    1984-01-01

    Research activities in cosmic rays, gamma rays, and astrophysical plasmas are reviewed. Energetic particle and photon detector systems flown on spacecraft and balloons were used to carry out the investigations. Specific instruments mentioned are: the high energy isotope spectrometer telescope, the electron/isotope spectrometer, the heavy isotope spectrometer telescope, and magnetometers. Solar flares, planetary magnetospheres, element abundance, the isotopic composition of low energy cosmic rays, and heavy nuclei are among the topics receiving research attention.

  5. A Cerenkov-delta E-Cerenkov detector for high energy cosmic ray isotopes and an accelerator study of Ar-40 and Fe-56 fragmentation. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Lau, K. H.

    1985-01-01

    A high energy cosmic ray detector--the High Energy Isotope Spectrometer Telescope (HEIST) is described. It is a large area (0.25 m(swp 2) SR) balloon borne isotope spectrometer designed to make high resolution measurements of isotopes in the element range from neon to nickel (10 Z 28) at energies of about 2 GeV/nucleon. HEIST determines the mass of individual nuclei by measuring both the change in the Lorentz factor (delta gamma) that results from traversing the NaI stack, and the energy loss (delta E) in the stack. Since the total energy of an isotope is given by E = (gamma M), the mass M can be determined by M = delta E/delta, gamma. The instrument is designed to achieve a typical mass resolution of 0.2 amu. The isotopic composition of the fragments from the breakup of high energy An-40 and Fe-56 nuclei are measured experimentally. Isotope yields are compared with calculated yields based on semi-empirical cross-section formulae.

  6. Study of Celestial Objects with Very High Energy Gamma Rays CANGAROO III

    E-print Network

    Enomoto, Ryoji

    Study of Celestial Objects with Very High Energy Gamma Rays CANGAROO III Project Description Collaboration between Australia and Nippon for a GAmma Ray Observatory in the Outback Institute for Cosmic Ray Energy Universe'' Gamma () rays are the highest energy band of electromagnetic radiation; located

  7. INTERACTING COSMIC RAYS WITH MOLECULAR CLOUDS: A BREMSSTRAHLUNG ORIGIN OF DIFFUSE HIGH-ENERGY EMISSION FROM THE INNER 2 Degree-Sign Multiplication-Sign 1 Degree-Sign OF THE GALACTIC CENTER

    SciTech Connect

    Yusef-Zadeh, F.; Roberts, D. A.; Royster, M. [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States)] [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Hewitt, J. W. [Code 662, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [Code 662, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Wardle, M. [Department of Physics and Astronomy, and Research Center for Astronomy, Astrophysics and Astrophotonics, Macquarie University, Sydney, NSW 2109 (Australia)] [Department of Physics and Astronomy, and Research Center for Astronomy, Astrophysics and Astrophotonics, Macquarie University, Sydney, NSW 2109 (Australia); Tatischeff, V. [Center de Spectrometrie Nucleaire et de Spectrometrie de Massse, IN2P3/CNRS and Univ. Paris-Sud, F-91405 Orsay Campus (France)] [Center de Spectrometrie Nucleaire et de Spectrometrie de Massse, IN2P3/CNRS and Univ. Paris-Sud, F-91405 Orsay Campus (France); Cotton, W. [NRAO, 520 Edgemont Road, Charlottesville, VA 22903 (United States)] [NRAO, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Uchiyama, H.; Nobukawa, M.; Tsuru, T. G. [Cosmic Ray Group, Physics, Kyoto University, Kitashirakawa-Oiwake-Cho, Sakyo, Kyoto 606-8502 (Japan)] [Cosmic Ray Group, Physics, Kyoto University, Kitashirakawa-Oiwake-Cho, Sakyo, Kyoto 606-8502 (Japan); Heinke, C. [Department of Physics, Room 238 CEB, University of Alberta, Edmonton, AB T6G 2G7 (Canada)] [Department of Physics, Room 238 CEB, University of Alberta, Edmonton, AB T6G 2G7 (Canada)

    2013-01-01

    The high-energy activity in the inner few degrees of the Galactic center is traced by diffuse radio, X-ray, and {gamma}-ray emission. The physical relationship between different components of diffuse gas emitting at multiple wavelengths is a focus of this work. We first present radio continuum observations using the Green Bank Telescope and model the nonthermal spectrum in terms of a broken power-law distribution of {approx}GeV electrons emitting synchrotron radiation. We show that the emission detected by Fermi is primarily due to nonthermal bremsstrahlung produced by the population of synchrotron emitting electrons in the GeV energy range interacting with neutral gas. The extrapolation of the electron population measured from radio data to low and high energies can also explain the origin of Fe I 6.4 keV line and diffuse TeV emission, as observed with Suzaku, XMM-Newton, Chandra, and the H.E.S.S. observatories. The inferred physical quantities from modeling multiwavelength emission in the context of bremsstrahlung emission from the inner {approx}300 Multiplication-Sign 120 pc of the Galactic center are constrained to have the cosmic-ray ionization rate {approx}1-10 Multiplication-Sign 10{sup -15} s{sup -1}, molecular gas heating rate elevating the gas temperature to 75-200 K, fractional ionization of molecular gas 10{sup -6}-10{sup -5}, large-scale magnetic field 10-20 {mu}G, the density of diffuse and dense molecular gas {approx}100 and {approx}10{sup 3} cm{sup -3} over 300 pc and 50 pc path lengths, and the variability of Fe I K{alpha} 6.4 keV line emission on yearly timescales. Important implications of our study are that GeV electrons emitting in radio can explain the GeV {gamma}-rays detected by Fermi and that the cosmic-ray irradiation model, like the model of the X-ray irradiation triggered by past activity of Sgr A*, can also explain the origin of the variable 6.4 keV emission from Galactic center molecular clouds.

  8. PAMELA Cosmic Ray Observations

    NASA Astrophysics Data System (ADS)

    Boezio, Mirko

    2012-07-01

    On the 15th of June 2006, the PAMELA satellite-borne experiment was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. The combination of a permanent magnet silicon strip spectrometer and a silicon-tungsten imaging calorimeter allows precision studies of the charged cosmic radiation to be conducted over a wide energy range with high statistics. The primary scientific goal is the measurement of the antiproton and positron energy spectrum from few tens of MeV up to hundreds of GeV in order to search for exotic sources, such as dark matter particle annihilations, and testing models of cosmic-ray propagation in the galaxy and in the heliosphere. PAMELA is also searching for primordial antinuclei (anti-helium) and testing cosmic-ray propagation models through precise measurements of light nuclei and their isotopes. We will present the status and main results of the PAMELA experiment after six years in orbit.

  9. Catching Cosmic Rays with a DSLR

    ERIC Educational Resources Information Center

    Sibbernsen, Kendra

    2010-01-01

    Cosmic rays are high-energy particles from outer space that continually strike the Earth's atmosphere and produce cascades of secondary particles, which reach the surface of the Earth, mainly in the form of muons. These particles can be detected with scintillator detectors, Geiger counters, cloud chambers, and also can be recorded with commonly…

  10. In Search of Cosmic Rays

    NSDL National Science Digital Library

    Derek Streich

    2001-11-01

    The authors discuss the Cosmic Ray Observatory Project (CROP), focusing on their high school's participation in the project. Students build and monitor cosmic ray detectors to count and study cosmic rays and to determine whether or not the time of day inf

  11. Title of dissertation: A SEARCH FOR BURSTS OF VERY HIGH ENERGY GAMMA RAYS

    E-print Network

    California at Santa Cruz, University of

    ABSTRACT Title of dissertation: A SEARCH FOR BURSTS OF VERY HIGH ENERGY GAMMA RAYS WITH MILAGRO by cosmic gamma rays of energies E 100 GeV . The effective area of Milagro peaks at energies E 10 Te though the search was optimized primarily for detecting the emission from Gamma-Ray Bursts (GRBs

  12. Galactic Cosmic Rays: From Earth to Sources

    NASA Technical Reports Server (NTRS)

    Brandt, Theresa J.

    2012-01-01

    For nearly 100 years we have known that cosmic rays come from outer space, yet proof of their origin, as well as a comprehensive understanding of their acceleration, remains elusive. Direct detection of high energy (up to 10(exp 15)eV), charged nuclei with experiments such as the balloon-born, antarctic Trans-Iron Galactic Element Recorder (TIGER) have provided insight into these mysteries through measurements of cosmic ray abundances. The abundance of these rare elements with respect to certain intrinsic properties suggests that cosmic rays include a component of massive star ejecta. Supernovae and their remnants (SNe & SNRs), often occurring at the end of a massive star's life or in an environment including massive star material, are one of the most likely candidates for sources accelerating galactic comic ray nuclei up to the requisite high energies. The Fermi Gamma-ray Space Telescope Large Area Detector (Fermi LAT) has improved our understanding of such sources by widening the window of observable energies and thus into potential sources' energetic processes. In combination with multiwavelength observations, we are now better able to constrain particle populations (often hadron-dominated at GeV energies) and environmental conditions, such as the magnetic field strength. The SNR CTB 37A is one such source which could contribute to the observed galactic cosmic rays. By assembling populations of SNRs, we will be able to more definitively define their contribution to the observed galactic cosmic rays, as well as better understand SNRs themselves. Such multimessenger studies will thus illuminate the long-standing cosmic ray mysteries, shedding light on potential sources, acceleration mechanisms, and cosmic ray propagation.

  13. Interactions of Cosmic Ray Nuclei

    E-print Network

    K. Mannheim; R. Schlickeiser

    1994-02-16

    We present convenient formulae for the energy losses of energetic atomic nuclei over the entire energy range relevant to the physics of cosmic rays. Results are applied to a leaky-box equation with a complete loss term. Thereby we derive the equilibrium spectrum of cosmic rays in various types of galaxies. We emphasize a spectral break energy at 450 MeV independent of the matter density, resulting from the transition from Coulomb and ionization losses to pion production losses as the relevant cooling process for the cosmic ray nuclei . We comment on the possible cosmic ray origin of the cosmic gamma ray background.

  14. The high energy cosmic-radiation detection (HERD) facility onboard China's Space Station

    NASA Astrophysics Data System (ADS)

    Zhang, S. N.; Adriani, O.; Albergo, S.; Ambrosi, G.; An, Q.; Bao, T. W.; Battiston, R.; Bi, X. J.; Cao, Z.; Chai, J. Y.; Chang, J.; Chen, G. M.; Chen, Y.; Cui, X. H.; Dai, Z. G.; D'Alessandro, R.; Dong, Y. W.; Fan, Y. Z.; Feng, C. Q.; Feng, H.; Feng, Z. Y.; Gao, X. H.; Gargano, F.; Giglietto, N.; Gou, Q. B.; Guo, Y. Q.; Hu, B. L.; Hu, H. B.; He, H. H.; Huang, G. S.; Huang, J.; Huang, Y. F.; Li, H.; Li, L.; Li, Y. G.; Li, Z.; Liang, E. W.; Liu, H.; Liu, J. B.; Liu, J. T.; Liu, S. B.; Liu, S. M.; Liu, X.; Lu, J. G.; Mazziotta, M. N.; Mori, N.; Orsi, S.; Pearce, M.; Pohl, M.; Quan, Z.; Ryde, F.; Shi, H. L.; Spillantini, P.; Su, M.; Sun, J. C.; Sun, X. L.; Tang, Z. C.; Walter, R.; Wang, J. C.; Wang, J. M.; Wang, L.; Wang, R. J.; Wang, X. L.; Wang, X. Y.; Wang, Z. G.; Wei, D. M.; Wu, B. B.; Wu, J.; Wu, X.; Wu, X. F.; Xia, J. Q.; Xiao, H. L.; Xu, H. H.; Xu, M.; Xu, Z. Z.; Yan, H. R.; Yin, P. F.; Yu, Y. W.; Yuan, Q.; Zha, M.; Zhang, L.; Zhang, L.; Zhang, L. Y.; Zhang, Y.; Zhang, Y. J.; Zhang, Y. L.; Zhao, Z. G.

    2014-07-01

    The High Energy cosmic-Radiation Detection (HERD) facility is one of several space astronomy payloads of the cosmic lighthouse program onboard China's Space Station, which is planned for operation starting around 2020 for about 10 years. The main scientific objectives of HERD are indirect dark matter search, precise cosmic ray spectrum and composition measurements up to the knee energy, and high energy gamma-ray monitoring and survey. HERD is composed of a 3-D cubic calorimeter (CALO) surrounded by microstrip silicon trackers (STKs) from five sides except the bottom. CALO is made of about 104 cubes of LYSO crystals, corresponding to about 55 radiation lengths and 3 nuclear interaction lengths, respectively. The top STK microstrips of seven X-Y layers are sandwiched with tungsten converters to make precise directional measurements of incoming electrons and gamma-rays. In the baseline design, each of the four side SKTs is made of only three layers microstrips. All STKs will also be used for measuring the charge and incoming directions of cosmic rays, as well as identifying back scattered tracks. With this design, HERD can achieve the following performance: energy resolution of 1% for electrons and gamma-rays beyond 100 GeV, 20% for protons from 100 GeV to 1 PeV; electron/proton separation power better than 10-5; effective geometrical factors of >3 m2sr for electron and diffuse gamma-rays, >2 m2sr for cosmic ray nuclei. R and D is under way for reading out the LYSO signals with optical fiber coupled to image intensified CCD and the prototype of one layer of CALO.

  15. Research Paper Cosmic Ray Impact on Extrasolar Earth-Like Planets in Close-in Habitable Zones

    Microsoft Academic Search

    J.-M. GRIEßMEIER; A. STADELMANN; U. MOTSCHMANN; N. K. BELISHEVA; H. LAMMER; H. K. BIERNAT

    Because of their different origins, cosmic rays can be subdivided into galactic cosmic rays and solar\\/stellar cosmic rays. The flux of cosmic rays to planetary surfaces is mainly determined by two planetary parameters: the atmospheric density and the strength of the internal mag- netic moment. If a planet exhibits an extended magnetosphere, its surface will be protected from high-energy cosmic

  16. EXTRAGALACTIC VERY HIGH ENERGY GAMMA-RAY BACKGROUND

    SciTech Connect

    Neronov, A. [ISDC Data Center for Astrophysics, Chemin d'Ecogia 16, CH-1290 Versoix (Switzerland); Semikoz, D. V. [APC, 10 rue Alice Domon et Leonie Duquet, F-75205 Paris Cedex 13 (France)

    2012-09-20

    We study the origin of the extragalactic diffuse gamma-ray background using the data from the Fermi telescope. To estimate the background level, we count photons at high Galactic latitudes |b| > 60 Degree-Sign . Subtracting photons associated with known sources and the residual cosmic-ray and Galactic diffuse backgrounds, we estimate the extragalactic gamma-ray background (EGB) flux. We find that the spectrum of EGB in the very high energy band above 30 GeV follows the stacked spectrum of BL Lac objects. Large Area Telescope data reveal the positive (1 + z) {sup k}, 1 < k < 4 cosmological evolution of the BL Lac source population consistent with that of their parent population, Fanaroff-Riley type I radio galaxies. We show that EGB at E > 30 GeV could be completely explained by emission from unresolved BL Lac objects if k {approx_equal} 3.

  17. Very High Energy Gamma Ray Astronomy.

    NASA Astrophysics Data System (ADS)

    Goodman, Jordan

    2008-04-01

    In the last decade the number of detected TeV gamma ray sources has gone up by more than an order of magnitude. This is due to the increased sensitivity of the current generation of telescopes. Imaging Atmospheric Cherenkov Telescopes such as HESS, Magic and VERITAS have exploited their high sensitivity and excellent angular resolution to discovered and map new classes of galactic gamma ray sources while continuing to discover and monitor extra-galactic AGN. In addition, Milagro, using water Cherenkov technology, has used its large field of view and continuous exposure to observe large scale diffuse emission from the Galactic plane and extended sources. In addition it has detected galactic sources with flat spectra extending beyond 100 TeV. The combination of these techniques are giving us a new view of the TeV sky and providing tantalizing evidence of the sources of Galactic cosmic rays. This talk will review recent results and discuss prospects for future detectors.

  18. Discovery of Very-High-Energy Gamma-Rays from the Galactic Centre Ridge

    E-print Network

    The H. E. S. S. Collaboration; :; F. A. Aharonian

    2006-03-01

    The origin of Galactic cosmic rays (with energies up to 10^15 eV) remains unclear, though it is widely believed that they originate in the shock waves of expanding supernova remnants. Currently the best way to investigate their acceleration and propagation is by observing the gamma-rays produced when cosmic rays interact with interstellar gas. Here we report observations of an extended region of very high energy (VHE, >100 GeV) gamma-ray emission correlated spatially with a complex of giant molecular clouds in the central 200 pc of the Milky Way. The hardness of the gamma-ray spectrum and the conditions in those molecular clouds indicate that the cosmic rays giving rise to the gamma-rays are likely to be protons and nuclei rather than electrons. The energy associated with the cosmic rays could have come from a single supernova explosion around 10,000 years ago.

  19. Cosmic Rays: "A Thin Rain of Charged Particles."

    ERIC Educational Resources Information Center

    Friedlander, Michael

    1990-01-01

    Discussed are balloons and electroscopes, understanding cosmic rays, cosmic ray paths, isotopes and cosmic-ray travel, sources of cosmic rays, and accelerating cosmic rays. Some of the history of the discovery and study of cosmic rays is presented. (CW)

  20. Cosmic Rays in Thunderstorms

    NASA Astrophysics Data System (ADS)

    Buitink, Stijn; Scholten, Olaf; van den Berg, Ad; Ebert, Ute

    2013-04-01

    Cosmic Rays in Thunderstorms Cosmic rays are protons and heavier nuclei that constantly bombard the Earth's atmosphere with energies spanning a vast range from 109 to 1021 eV. At typical altitudes up to 10-20 km they initiate large particle cascades, called extensive air showers, that contain millions to billions of secondary particles depending on their initial energy. These particles include electrons, positrons, hadrons and muons, and are concentrated in a compact particle front that propagates at relativistic speed. In addition, the shower leaves behind a trail of lower energy electrons from ionization of air molecules. Under thunderstorm conditions these electrons contribute to the electrical and ionization processes in the cloud. When the local electric field is strong enough the secondary electrons can create relativistic electron run-away avalanches [1] or even non-relativistic avalanches. Cosmic rays could even trigger lightning inception. Conversely, strong electric fields also influence the development of the air shower [2]. Extensive air showers emit a short (tens of nanoseconds) radio pulse due to deflection of the shower particles in the Earth's magnetic field [3]. Antenna arrays, such as AERA, LOFAR and LOPES detect these pulses in a frequency window of roughly 10-100 MHz. These systems are also sensitive to the radiation from discharges associated to thunderstorms, and provide a means to study the interaction of cosmic ray air showers and the electrical processes in thunderstorms [4]. In this presentation we discuss the involved radiation mechanisms and present analyses of thunderstorm data from air shower arrays [1] A. Gurevich et al., Phys. Lett. A 165, 463 (1992) [2] S. Buitink et al., Astropart. Phys. 33, 1 (2010) [3] H. Falcke et al., Nature 435, 313 (2005) [4] S. Buitink et al., Astron. & Astrophys. 467, 385 (2007)

  1. Relativistic heavy cosmic rays

    NASA Technical Reports Server (NTRS)

    Mewaldt, R. A.; Fernandez, J. I.; Israel, M. H.; Klarmann, J.; Binns, W. R.

    1972-01-01

    During three balloon flights of a 1 sq m sr ionization chamber/Cerenkov counter detector system, measurements were made of the atmospheric attenuation, flux, and charge composition of cosmic ray nuclei with 16 is less than or = Z is less than or = 30 and rigidity greater than 4.5 GV. The attenuation mean free path in air of VH (20 less than or = Z less than or = 30) nuclei is found to be 19.7 + or - 1.6 g/sq cm, a value somewhat greater than the best previous measurement. The attenuation mean free path of iron is found to be 15.6 + or - 2.2 g/sq cm, consistent with predictions of geometric cross-section formulae. An absolute flux of VH nuclei 10 to 20% higher than earlier experiments at similar geomagnetic cutoff and level of solar activity was measured. The relative abundances of even-charged nuclei are found to be in good agreement with results of other recent high resolution counter experiments. The observed cosmic ray chemical composition implies relative abundances at the cosmic ray source of Ca/Fe = 0.12 + or - 0.04 and S/Fe = 0.14 + or - 0.05.

  2. High-energy cosmic neutrinos from spine-sheath BL Lac jets

    E-print Network

    Tavecchio, F

    2014-01-01

    We recently proposed that structured (spine-sheath) jets associated to BL Lac objects offer a suitable environment for the production of the extragalactic high-energy ($E>100$ TeV) neutrino recently revealed by IceCube. Our previous analysis was limited to low-power BL Lac objects. We extend our preliminary study to the entire BL Lac population. We assume that the power of cosmic rays as well as the radiative luminosity of the sheath depend linearly on the the jet power. In turn, we assume that the latter is well traced by the $\\gamma$-ray luminosity. We exploit the BL Lac $\\gamma$-ray luminosity function and its cosmic evolution as recently inferred from Fermi-LAT data to derive the expected neutrino cumulative intensity from the entire BL Lac population. When considering only the low-power BL Lacs, a large cosmic ray power for each source is required to account for the neutrino flux. Instead, if BL Lacs of all powers produce neutrinos, the power demand decreases, and the required cosmic ray power becomes of...

  3. High-Energy Transmission Grating Spectrometer for the Advanced X-ray Astrophysics Facility (AXAF)

    Microsoft Academic Search

    Thomas H. Markert; Claude R. Canizares; Daniel Dewey; Michael McGuirk; Chris S. Pak; Mark L. Schattenburg

    1994-01-01

    The High Energy Transmission Grating Spectrometer (HETGS) is one of the scientific instruments being developed for NASA's Advanced X-ray Astrophysics Facility (AXAF), scheduled for launch in 1998. The HETGS will be capable of measuring spectra with high resolution and sensitivity from a variety of compact and slightly extended cosmic X-ray sources. In this paper we describe the overall design of

  4. Research Concerning Detection of Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Grady, Maxwell; Cunningham, John; Kuhlmann, Steve; Spinka, Hal; Underwood, Dave; Hammergren, Mark

    2010-02-01

    Throughout my academic career at Loyola I have carried out research with the Loyola University Cosmic Event Detection System concerning the possibility of detection of ultra high energy cosmic rays (UHECRs) based on radio meteor scattering methods. This research was furthered through summer internships and research fellowships at Adler Planetarium Chicago and Stony Brook University in New York. At Adler Planetarium we used a helium balloon carrying a Geiger counter and other equipment to record the cosmic ray flux at various points in the atmosphere. The results clearly show the flux depends on the atmospheric density. At Stony Brook University I studied their advanced system for detecting cosmic rays in similar manner to radio meteor scattering principles. Research there focused on detection algorithms and also on the possibility of utilizing Digital Tv (DTv) signals for further research. Through the research a solid understanding of cosmic rays was formed including topics such as origins and energy scales of cosmic rays, both of which pose unanswered questions. )

  5. How to Detect Cosmic Rays

    NSDL National Science Digital Library

    In this lesson on cosmic rays, students will explain two examples of a cosmic ray detector. Includes information about student preconceptions and a demonstration that requires a geiger counter and optional access to a small radioactive source that emits energetic helium nuclei (alpha particles), e.g., the mineral the mineral autunite, which contains uranium. This is activity two of four from The Cosmic Ray Telescope for the Effects of Radiation (CRaTER).

  6. Cosmic Rays and Space Weather

    Microsoft Academic Search

    Lev I. Dorman

    2010-01-01

    \\u000a This lecture is an example how fundamental research in Cosmic Ray Astrophysics and Geophysics can be applied to very important\\u000a modern practical problem: monitoring by cosmic rays space weather and prediction by using on-line cosmic ray data space phenomena\\u000a dangerous for satellites electronics and astronauts health in the space, for crew and passengers health on commercial jets\\u000a in atmosphere, and

  7. Cosmic Rays and Climate Change

    NASA Astrophysics Data System (ADS)

    Erlykin, A. D.; Laken, B. A.; Sloan, T.; Wolfendale, A. W.

    2010-09-01

    A survey is made of the evidence for and against the hypothesis that cosmic rays affect cloud cover and thereby surface temperature. The analysis is made for the troposphere in the main and it includes correlations of cloud cover with cosmic ray intensity, Forbush decreases, cosmic ray short period increases and eleven year changes; also included are the electrical effects associated with cosmic rays. A complementary study comprises a search for extra cloud cover associated with terrestrial radon emissions, the Chernobyl accident and nuclear bomb tests. It is concluded that the best estimate of the fraction of (low) cloud cover attributable to a 2% change in cosmic ray intensity is about 0.02%. Insofar as the maximum change in average cosmic ray intensity over the last 50 years is about 0.2%, no more than 0.01% of cloud cover change in this period can have been caused by cosmic rays; their contribution to Global Warming is thus considered to be negligible. Not surprisingly, we find that the effect of cosmic rays on stratospheric cloud is bigger, by a factor of at least ten. In both the troposphere and the stratosphere the cosmic ray effects at the Poles are bigger than average.

  8. The LDEF ultra heavy cosmic ray experiment

    NASA Technical Reports Server (NTRS)

    Osullivan, D.; Thompson, A.; Bosch, J.; Keegan, R.; Wenzel, K.-P.; Smit, A.; Domingo, C.

    1991-01-01

    The Long Duration Exposure Facility (LDEF) Ultra Heavy Cosmic Ray Experiment (UHCRE) used 16 side viewing LDEF trays giving a total geometry factor for high energy cosmic rays of 30 sq m sr. The total exposure factor was 170 sq m sr y. The experiment is based on a modular array of 192 solid state nuclear track detector stacks, mounted in sets of 4 pressure vessels (3 experiment tray). The extended duration of the LDEF mission has resulted in a greatly enhanced potential scientific yield from the UHCRE. Initial scanning results indicate that at least 2000 cosmic ray nuclei with Z greater than 65 were collected, including the world's first statistically significant sample of actinides. Postflight work to date and the current status of the experiment are reviewed. Provisional results from analysis of preflight and postflight calibrations are presented.

  9. The LDEF ultra heavy cosmic ray experiment

    NASA Technical Reports Server (NTRS)

    Osullivan, D.; Thompson, A.; Bosch, J.; Keegan, R.; Wenzel, K.-P.; Smit, A.; Domingo, C.

    1992-01-01

    The LDEF Ultra Heavy Cosmic Ray Experiment (UHCRE) used 16 side viewing LDEF trays giving a total geometry factor for high energy cosmic rays of 30 sq m sr. The total exposure factor was 170 sq m sr y. The experiment is based on a modular array of 192 solid state nuclear track detector stacks, mounted in sets of four in 48 pressure vessels. The extended duration of the LDEF mission has resulted in a greatly enhanced potential scientific yield from the UHCRE. Initial scanning results indicate that at least 1800 cosmic ray nuclei with Z greater than 65 were collected, including the world's first statistically significant sample of actinides. Post flight work to date and the current status of the experiment are reviewed.

  10. Muon acceleration in cosmic-ray sources

    SciTech Connect

    Klein, Spencer R.; Mikkelsen, Rune E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Becker Tjus, Julia [Fakultät für Physik and Astronomie, Theoretische Physik I, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2013-12-20

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in gamma-ray bursts, magnetars, or other sources. These transient sources have short lifetimes, which necessitate very high accelerating gradients, up to 10{sup 13} keV cm{sup –1}. At gradients above 1.6 keV cm{sup –1}, muons produced by hadronic interactions undergo significant acceleration before they decay. This muon acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. Using the IceCube high-energy diffuse neutrino flux limits, we set two-dimensional limits on the source opacity and matter density, as a function of accelerating gradient. These limits put strong constraints on different models of particle acceleration, particularly those based on plasma wake-field acceleration, and limit models for sources like gamma-ray bursts and magnetars.

  11. Muon Acceleration in Cosmic-Ray Sources

    NASA Astrophysics Data System (ADS)

    Klein, Spencer R.; Mikkelsen, Rune E.; Becker Tjus, Julia

    2013-12-01

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in gamma-ray bursts, magnetars, or other sources. These transient sources have short lifetimes, which necessitate very high accelerating gradients, up to 1013 keV cm-1. At gradients above 1.6 keV cm-1, muons produced by hadronic interactions undergo significant acceleration before they decay. This muon acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. Using the IceCube high-energy diffuse neutrino flux limits, we set two-dimensional limits on the source opacity and matter density, as a function of accelerating gradient. These limits put strong constraints on different models of particle acceleration, particularly those based on plasma wake-field acceleration, and limit models for sources like gamma-ray bursts and magnetars.

  12. Very high energy gamma ray astrophysics

    SciTech Connect

    Lamb, R.C.; Lewis, D.A.

    1992-02-01

    The second reflector (project GRANITE) is on schedule. At present (January 1992) it and the 10 m reflector are obtaining stereoscopic views of gamma-ray air showers from the Crab Nebula which verify the expected performance of the twin reflector telescopes. With the additional improvements of the upgrade (a pending DOE proposal) the twin reflectors should reach a limiting intensity of 1% that of the Crab. The astonishing early results from the EGRET detector aboard the Compton Gamma Ray Observatory indicate that distant quasars (powered by supermassive black holes) are active at GeV energies. The Whipple instruments are poised to see if such behavior continues above 100 GeV, as well as perform sensitive observations of previously reported GeV (Geminga) and TeV (Hercules X-1, etc.) sources. In addition to observing sources and identifying their location in the sky to one arcminute, experiments are planned to search for WIMPS in the mass range 0.1 to 1 TeV, and to determine the abundance of anti-protons in the cosmic rays. The successful performance of the stereoscopic reflectors demonstrates the feasibility of the concept of arrays of Cherenkov receivers. Design studies for a much larger array (CASITA) are just beginning.

  13. Antiprotons in cosmic rays

    NASA Technical Reports Server (NTRS)

    Balasubrahmanyan, V. K.; Ormes, J. F.; Streitmatter, R. E.

    1987-01-01

    Recent experimental observations and results are discussed. It was found that the approximately 50 antiprotons collected in balloon experiments to date have generated considerable theoretical interest. Clearly, confirmatory experiments and measurements over an extended energy range are required before definite conclusions are drawn. Antiproton measurements have a bearing on astrophysical problems ranging from cosmic ray propagation to issues of cosmological import. The next generation of balloon experiments and the Particle Astrophysics Magnet Facility being discussed for operation on NASA's space station should provide data and insights of highest interest.

  14. Ultra heavy cosmic ray experiment (A0178)

    NASA Technical Reports Server (NTRS)

    Thompson, A.; Osullivan, D.; Bosch, J.; Keegan, R.; Wenzel, K. P.; Jansen, F.; Domingo, C.

    1992-01-01

    The Ultra Heavy Cosmic Ray Experiment (UHCRE) is based on a modular array of 192 side viewing solid state nuclear track detector stacks. These stacks were mounted in sets of four in 48 pressure vessels using 16 peripheral LDEF trays. The geometry factor for high energy cosmic ray nuclei, allowing for Earth shadowing, was 30 sq m sr, giving a total exposure factor of 170 sq m sr y at an orbital inclination of 28.4 degs. Scanning results indicate that about 3000 cosmic ray nuclei in the charge region with Z greater than 65 were collected. This sample is more than ten times the current world data in the field (taken to be the data set from the HEAO-3 mission plus that from the Ariel-6 mission) and is sufficient to provide the world's first statistically significant sample of actinide cosmic rays. Results are presented including a sample of ultra heavy cosmic ray nuclei, analysis of pre-flight and post-flight calibration events and details of track response in the context of detector temperature history. The integrated effect of all temperature and age related latent track variations cause a maximum charge shift of + or - 0.8e for uranium and + or - 0.6e for the platinum-lead group. Astrophysical implications of the UHCRE charge spectrum are discussed.

  15. Spiral arms as cosmic ray source distributions

    NASA Astrophysics Data System (ADS)

    Werner, M.; Kissmann, R.; Strong, A. W.; Reimer, O.

    2015-04-01

    The Milky Way is a spiral galaxy with (or without) a bar-like central structure. There is evidence that the distribution of suspected cosmic ray sources, such as supernova remnants, are associated with the spiral arm structure of galaxies. It is yet not clearly understood what effect such a cosmic ray source distribution has on the particle transport in our Galaxy. We investigate and measure how the propagation of Galactic cosmic rays is affected by a cosmic ray source distribution associated with spiral arm structures. We use the PICARD code to perform high-resolution 3D simulations of electrons and protons in galactic propagation scenarios that include four-arm and two-arm logarithmic spiral cosmic ray source distributions with and without a central bar structure as well as the spiral arm configuration of the NE2001 model for the distribution of free electrons in the Milky Way. Results of these simulation are compared to an axisymmetric radial source distribution. Also, effects on the cosmic ray flux and spectra due to different positions of the Earth relative to the spiral structure are studied. We find that high energy electrons are strongly confined to their sources and the obtained spectra largely depend on the Earth's position relative to the spiral arms. Similar finding have been obtained for low energy protons and electrons albeit at smaller magnitude. We find that even fractional contributions of a spiral arm component to the total cosmic ray source distribution influences the spectra on the Earth. This is apparent when compared to an axisymmetric radial source distribution as well as with respect to the Earth's position relative to the spiral arm structure. We demonstrate that the presence of a Galactic bar manifests itself as an overall excess of low energy electrons at the Earth. Using a spiral arm geometry as a cosmic ray source distributions offers a genuine new quality of modeling and is used to explain features in cosmic ray spectra at the Earth that are else-wise attributed to other propagation effects. We show that realistic cosmic ray propagation scenarios have to acknowledge non-axisymmetric source distributions.

  16. Cosmic Rays and Experiment CZELTA

    SciTech Connect

    Smolek, Karel; Nyklicek, Michal [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Kovacikova, Petra [Faculty of Philosophy and Science, Silesian University in Opava, Bezrucovo namesti 13, 746 01 Opava (Czech Republic)

    2007-11-26

    This paper gives a review of the physics of cosmic rays with emphasis on the methods of detection and study. A summary is given of the Czech project CZELTA which is part of a multinational program to study cosmic rays with energies above 10{sup 14} eV.

  17. Cosmic Ray Neutron Flux Measurements

    NASA Astrophysics Data System (ADS)

    Dayananda, Mathes

    2009-11-01

    Cosmic rays are high-energetic particles originating from outer space that bombard the upper atmosphere of the Earth. Almost 90% of cosmic ray particles consist of protons, electrons and heavy ions. When these particles hit the Earth's atmosphere, cascade of secondary particles are formed. The most abundant particles reach to the surface of the Earth are muons, electrons and neutrons. In recent years many research groups are looking into potential applications of the effects of cosmic ray radiation at the surface of the Earth [1, 2]. At Georgia State University we are working on a long-term measurement of cosmic ray flux distribution. This study includes the simultaneous measurement of cosmic ray muons, neutrons and gamma particles at the Earth surface in downtown Atlanta. The initial effort is focusing on the correlation studies of the cosmic ray particle flux distribution and the atmospheric weather conditions. In this presentation, I will talk about the development of a cosmic ray detector using liquid scintillator and the preliminary results. [4pt] [1] K.Borozdin, G.Hogan, C.Morris, W.Priedhorsky, A.Saunders, L.Shultz, M.Teasdale, ``Radiographic imaging with cosmic-ray muons'', Nature, Vol.422, p.277, Mar.2003[0pt] [2] Svensmark Henrik, Physical Review 81, 3, (1998)

  18. Single particle effects, Biostack, and risk evaluation - Studies on the radiation risk from Galactic cosmic rays

    NASA Technical Reports Server (NTRS)

    Curtis, Stanley B.

    1993-01-01

    The possible health risks posed by Galactic cosmic rays, especially the possible heightened cancer risk, are examined. The results of the Biostack studies of the biological effects of high-energy cosmic rays are discussed. The biological mechanisms involved in possible harm due to cosmic rays are considered.

  19. Cosmic-ray acceleration in supernova shocks

    E-print Network

    Vincent Tatischeff

    2008-07-25

    Galactic cosmic rays are widely believed to be accelerated in expanding shock waves initiated by supernova explosions. The theory of diffusive shock acceleration of cosmic rays is now well established, but two fundamental questions remain partly unanswered: what is the acceleration efficiency, i.e. the fraction of the total supernova energy converted to cosmic-ray energy, and what is the maximum kinetic energy achieved by particles accelerated in supernova explosions? Recent observations of supernova remnants, in X-rays with the Chandra and XMM-Newton satellites and in very-high-energy gamma rays with several ground-based atmospheric Cerenkov telescopes, have provided new pieces of information concerning these two questions. After a review of these observations and their current interpretations, I show that complementary information on the diffusive shock acceleration process can be obtained by studying the radio emission from extragalactic supernovae. As an illustration, a nonlinear model of diffusive shock acceleration is applied to the radio light curves of the supernova SN 1993J, which exploded in the nearby galaxy M81. The results of the model suggest that most of the Galactic cosmic rays may be accelerated during the early phase of interaction between the supernova ejecta and the wind lost from the progenitor star.

  20. Gamma rays from grazing incidence cosmic rays in the earth's atmosphere

    NASA Technical Reports Server (NTRS)

    Ulmer, Andrew

    1994-01-01

    Interactions of grazing incidence, ultra high-energy cosmic rays with the earth's atmosphere may provide a new method of studying energetic cosmic rays with gamma-ray satellites. It is found that these cosmic ray interactions may produce gamma-rays on millisecond timescales which may be detectable by satellites. An extremely low gamma-ray background for transient gamma-ray events and a large area of interaction, the earth's surface, make the scheme plausible. The effective cross section of detection of interactions for cosmic rays above 10(exp 20) eV is found to be more than two orders of magnitude higher than Earth-based detection techniques. This method may eventually offer an efficient way of probing this region of the cosmic-ray energy spectrum where events are scarce. In this paper, a conceptual model is presented for the production of short bursts of gamma-rays based on these grazing incidence encounters with the Earth's atmosphere.

  1. Muon Acceleration in Cosmic-ray Sources

    E-print Network

    Klein, Spencer R; Tjus, Julia K Becker

    2012-01-01

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in Gamma-Ray Bursts magnetars, or other sources. These source models require very high accelerating gradients, $10^{13}$ keV/cm, with the minimum gradient set by the length of the source. At gradients above 1.6 keV/cm, muons produced by hadronic interactions undergo significant acceleration before they decay. This acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. We rule out many models of linear acceleration, setting strong constraints on plasma wakefield accelerators and on models for sources like Gamma Ray Bursts and magnetars.

  2. Muon Acceleration in Cosmic-ray Sources

    E-print Network

    Spencer R. Klein; Rune Mikkelsen; Julia K. Becker Tjus

    2012-08-09

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in Gamma-Ray Bursts magnetars, or other sources. These source models require very high accelerating gradients, $10^{13}$ keV/cm, with the minimum gradient set by the length of the source. At gradients above 1.6 keV/cm, muons produced by hadronic interactions undergo significant acceleration before they decay. This acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. We rule out many models of linear acceleration, setting strong constraints on plasma wakefield accelerators and on models for sources like Gamma Ray Bursts and magnetars.

  3. The H.E.S.S. measurement of the cosmic-ray electron spectrum

    Microsoft Academic Search

    Kathrin Egberts; A. Abramowski; F. Acero; F. Aharonian; A. G. Akhperjanian; G. Anton; U. Barres de Almeida; A. R. Bazer-Bachi; Y. Becherini; B. Behera; K. Bernlühr; A. Bochow; C. Boisson; J. Bolmont; V. Borrel; J. Brucker; F. Brun; P. Brun; R. Bühler; T. Bulik; I. Büsching; T. Boutelier; P. M. Chadwick; A. Charbonnier; R. C. G. Chaves; A. Cheesebrough; J. Conrad; L.-M. Chounet; A. C. Clapson; G. Coignet; M. Dalton; M. K. Daniel; I. D. Davids; B. Degrange; C. Deil; H. J. Dickinson; A. Djannati-Ataü W. Domainko; L. O'c. Drury; F. Dubois; G. Dubus; J. Dyks; M. Dyrda; P. Eger; P. Espigat; L. Fallon; C. Farnier; S. Fegan; F. Feinstein; M. V. Fernandes; A. Fiasson; A. Fürster; G. Fontaine; M. Füssling; S. Gabici; Y. A. Gallant; L. Gérard; D. Gerbig; B. Giebels; J. F. Glicenstein; B. Glück; P. Goret; D. Güring; D. Hampf; M. Hauser; S. Heinz; G. Heinzelmann; G. Henri; G. Hermann; J. A. Hinton; A. Hoffmann; W. Hofmann; P. Hofverberg; M. Holleran; S. Hoppe; D. Horns; A. Jacholkowska; O. C. de Jager; C. Jahn; I. Jung; K. Katarzynski; U. Katz; S. Kaufmann; M. Kerschhaggl; D. Khangulyan; B. Khálifi; D. Keogh; D. Klochkov; W. Kluzniak; T. Kneiske; Nu. Komin; K. Kosack; R. Kossakowski; G. Lamanna; J.-P. Lenain; T. Lohse; C.-C. Lu; V. Marandon; A. Marcowith; J. Masbou; D. Maurin; T. J. L. McComb; M. C. Medina; J. Méhault; R. Moderski; E. Moulin; M. Naumann-Godo; M. de Naurois; D. Nedbal; D. Nekrassov; N. Nguyen; B. Nicholas; J. Niemiec; S. J. Nolan; S. Ohm; J.-F. Olive; E. de Ona Wilhelmi; B. Opitz; K. J. Orford; M. Ostrowski; M. Panter; M. Paz Arribas; G. Pedaletti; G. Pelletier; P.-O. Petrucci; S. Pita; G. Pühlhofer; M. Punch; A. Quirrenbach; B. C. Raubenheimer; M. Raue; S. M. Rayner; O. Reimer; M. Renaud; R. de Los Reyes; F. Rieger; J. Ripken; L. Rob; S. Rosier-Lees; G. Rowell; B. Rudak; C. B. Rulten; J. Ruppel; F. Ryde; V. Sahakian; A. Santangelo; R. Schlickeiser; F. M. Schück; A. Schünwald; U. Schwanke; S. Schwarzburg; S. Schwemmer; A. Shalchi; I. Sushch; M. Sikora; J. L. Skilton; H. Sol; L. Stawarz; R. Steenkamp; C. Stegmann; F. Stinzing; A. Szostek; P. H. Tam; J.-P. Tavernet; R. Terrier; O. Tibolla; M. Tluczykont; K. Valerius; C. van Eldik; G. Vasileiadis; C. Venter; L. Venter; J. P. Vialle; A. Viana; P. Vincent; M. Vivier; H. J. Vülk; F. Volpe; S. Vorobiov; S. J. Wagner; M. Ward; A. A. Zdziarski; A. Zech; H.-S. Zechlin

    2010-01-01

    The measurement of very-high-energy cosmic-ray electrons is intrinsically difficult due to their very steep spectrum with low fluxes and an enormous background of hadronic cosmic rays. The large collection areas needed for such a measurement can be provided by ground-based imaging atmospheric Cherenkov telescopes. The High Energy Stereoscopic System (H.E.S.S.) has performed the first ground-based cosmic-ray electron measurement and thereby

  4. Cosmic-Ray Positron Measurements

    NASA Astrophysics Data System (ADS)

    Schubnell, Michael

    Direct measurements of cosmic-ray electrons and positrons were first made in the early 1960s and since then a number of instruments were built to study this component of the cosmic radiation. The precise measurement of the intensities of CR electrons and positrons are key to our understanding of cosmic-ray origin and propagation. In addition the locally observed abundance of cosmic ray electrons and/or positrons may exhibit interesting spectral features. Observations confirm the almost exclusive secondary nature of positrons up to a few GeV but measurements by the HEAT-e instrument suggested as early as 1995 a possible primary positron component. More recent reports by the PAMELA team of a continued rise in the cosmic-ray positron fraction above about 10 GeV and of an excess of cosmic-ray electrons around a few hundred GeV by the ATIC collaboration have resulted in a flurry of publications interpreting these observations either as a possible dark matter signature or as a contribution from isolated astrophysical sources. While those interpretations are scientically exciting, the possibility that measurements are contaminated by misidentied cosmic-ray protons cannot be ignored. I will present a new analysis of low energy positron data taking into account modulation effects due to the solar cycle and I will take a critical look at current positron measurements and discuss theoretical interpretations from an experimentalist's point of view.

  5. ASPIRE - Cloud Chambers as an Introduction to Cosmic Ray Observation

    NASA Astrophysics Data System (ADS)

    Callahan, Julie; Matthews, John; Jui, Charles

    2012-03-01

    ASPIRE is the K12 - Education & Public Outreach program for the Telescope Array ultra-high energy cosmic ray research project in Utah. The Telescope Array experiment studies ultra-high energy cosmic rays with an array of ˜500 surface scintillator detectors and three fluorescence telescope stations observing over 300 square miles in the West Desert of Utah. Telescope Array is a collaboration of international institutions from the United States, Japan, Korea, Russia and Belgium. Cloud chambers are an inexpensive and easy demonstration to visually observe evidence of charged particles and cosmic ray activity both for informal events as well as for K12 classroom activities. Join us in building a cloud chamber and observe cosmic rays with these table-top demonstrations. A brief overview of the Telescope Array project in Millard County, Utah will also be presented.

  6. Pulsars, supernovae, and ultrahigh energy cosmic rays

    NASA Astrophysics Data System (ADS)

    Kotera, K.; Fang, K.; Olinto, A. V.; Phinney, E. S.

    2012-12-01

    The acceleration of ultrahigh energy nuclei in fast spinning newborn pulsars can explain the observed spectrum of ultrahigh energy cosmic rays and the trend towards heavier nuclei for energies above 10^{19} eV as indicated by air shower studies reported by the Auger Observatory. By assuming a normal distribution of pulsar birth periods centered at 300 ms, we show that the contribution of extragalactic pulsar births to the ultrahigh energy cosmic ray spectrum naturally gives rise to a contribution to very high energy cosmic rays (VHECRs, between 10^{16} and 10^{18} eV) by Galactic pulsar births. The required injected composition to fit the observed spectrum depends on the absolute energy scale, differing considerably between the energy scale used by Auger and that used by the Telescope Array. Depending on the composition of the cosmic rays that escape the supernova remnant and the diffusion behavior of VHECRs in the Galaxy, the contribution of Galactic pulsar births can also bridge the gap between predictions for cosmic ray acceleration in supernova remnants and the observed spectrum below the ankle. Fast spinning newborn pulsars that could produce UHECRs would be born in supernovae that could present interesting specific radiative features, due to the interaction of the pulsar wind with the surrounding ejecta. The resulting supernova lightcurves could present a high luminosity plateau over a few years, and a bright X-ray and gamma-ray peak around one or two years after the onset of the explosion. If such signatures were observed, they could have important implications both for UHECR astrophysics and for the understanding of core-collapse supernovae.

  7. Search for steady cosmic sources of high energy neutrinos in ANTARES

    NASA Astrophysics Data System (ADS)

    Gómez-González, J. P.

    2013-02-01

    ANTARES is the largest Neutrino Telescope operating in the Northern Hemisphere. Placed at the bottom of the Mediterranean Sea, about 40 km off the coast of Toulon (France), it is composed by 885 photomultiplier-tubes (PMTs) which detect the Cherenkov light emitted in the interaction of high energy neutrinos close or inside the detector. One of the main goals of the experiment is the identification of a source of cosmic neutrinos, which are likely to be produced in the interaction of high energy hadrons in several astrophysical scenarios. The discovery of a source of neutrinos will be, thus, a clear indication for hadronic acceleration mechanisms and shed light on the problem of the origin of cosmic rays (CRs). This works present such a search using 813 days of data collected in ANTARES between years 2007 and 2010. Not having found any significance excess of events upper limits to the E?--2 are given for sources in the Southern sky. Additionally, results using specific emission models for two well known gamma-ray TeV sources are discussed.

  8. Cosmic ray modulation by interplanetary disturbances

    NASA Astrophysics Data System (ADS)

    Braga, Carlos Roberto; Dal Lago, Alisson; Schuch, Nelson Jorge; da Silva, Marlos; Echer, Ezequiel; Demítrio Gonzalez Alarcon, Walter; Munakata, Kazuoki; Kuwabara, Takao; Kato, Chihiro; Bieber, John W.

    Interplanetary disturbances such as ICMEs (Interplanetary Coronal Mass Ejections) and CIRs (Corotating Interaction Regions), modulate high-energy cosmic rays reaching the Earth. Prior to the arrival of the disturbances at the Earth, ground based high-energy muon detectors can detect precursory effects in cosmic-ray anisotropy, such as precursory deficit and/or excess of intensity along the sunward IMF (Interplanetary Magnetic Field) direction. With suitable analyses, these precursors are found typically around 8 hours prior to the disturbance arrival at the Earth. The objective of this work is to analyze these precursors by using the Global Muon Detector Network (GMDN), an international network formed by four multidirectional muon detectors viewing a full range of the pitch angle measured from the sunward IMF direction. By analyzing the variation of the count rate global distribution of the observed intensity (instead of analyzing the count rate) precursory signatures can be enhanced when compared with analyses of count rates. For some events, it is possible to make almost a global distribution map of cosmic ray density using all the directional channels of the detectors. Precursory signature is generally accompanied by the interplanetary shock, but there are also some signatures not associated with the shock.

  9. Cosmic Rays and Global Warming

    E-print Network

    T. Sloan; A W Wolfendale

    2007-06-28

    It has been claimed by others that observed temporal correlations of terrestrial cloud cover with `the cosmic ray intensity' are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim to look for evidence to corroborate it. So far we have not found any and so our tentative conclusions are to doubt it. Such correlations as appear are more likely to be due to the small variations in solar irradiance, which, of course, correlate with cosmic rays. We estimate that less than 15% of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 35 years is due to this cause.

  10. Quantum Black Holes from Cosmic Rays

    E-print Network

    Xavier Calmet; Lauretiu Ioan Caramete; Octavian Micu

    2012-11-19

    We investigate the possibility for cosmic ray experiments to discover non-thermal small black holes with masses in the TeV range. Such black holes would result due to the impact between ultra high energy cosmic rays or neutrinos with nuclei from the upper atmosphere and decay instantaneously. They could be produced copiously if the Planck scale is in the few TeV region. As their masses are close to the Planck scale, these holes would typically decay into two particles emitted back-to-back. Depending on the angles between the emitted particles with respect to the center of mass direction of motion, it is possible for the simultaneous showers to be measured by the detectors.

  11. Gamma Ray Signatures from Ordinary Cosmic Strings

    E-print Network

    Jane H. MacGibbon; Robert H. Brandenberger

    1992-06-19

    We calculate the flux of ultra high energy photons from individual ordinary (i.e. non-superconducting) cosmic strings and compare the results with the sensitivity of current and proposed TeV and EeV telescopes. Our calculations give only upper limits for the gamma ray flux, since the source of the photons, jets from particle production at cusps, may be weakened by back reaction effects. For the usual cosmic distribution of strings, the predicted bursts from strings with the value of mass per unit length associated with galaxy formation or light strings may just be detectable. A diffuse gamma ray background from light strings may also be seen by the Fly's Eye detector at above $7 \\times 10^{10}$ GeV.

  12. Cosmic Ray Electron Science with GLAST

    NASA Technical Reports Server (NTRS)

    Ormes, J. F.; Moiseev, Alexander

    2007-01-01

    Cosmic ray electrons at high energy carry information about their sources, their definition in local magnetic fields and their interactions with the photon fields through which they travel. The spectrum of the particles is affected by inverse Compton losses and synchrotron losses, the rates of which are proportional to the square of the particle's energy making the spectra very steep. However, GLAST will be able to make unique and very high statistics measurements of electrons from approx. 20 to approx. 700 GeV that will allow us to search for anisotropies in anival direction and spectral features associated with some dark matter candidates. Complementary information on electrons of still higher energy will be required to see effects of possible individual cosmic ray sources.

  13. Cosmic ray propagation with CRPropa 3

    NASA Astrophysics Data System (ADS)

    Alves Batista, R.; Erdmann, M.; Evoli, C.; Kampert, K.-H.; Kuempel, D.; Mueller, G.; Sigl, G.; Van Vliet, A.; Walz, D.; Winchen, T.

    2015-05-01

    Solving the question of the origin of ultra-high energy cosmic rays (UHECRs) requires the development of detailed simulation tools in order to interpret the experimental data and draw conclusions on the UHECR universe. CRPropa is a public Monte Carlo code for the galactic and extragalactic propagation of cosmic ray nuclei above ? 1017 eV, as well as their photon and neutrino secondaries. In this contribution the new algorithms and features of CRPropa 3, the next major release, are presented. CRPropa 3 introduces time-dependent scenarios to include cosmic evolution in the presence of cosmic ray deflections in magnetic fields. The usage of high resolution magnetic fields is facilitated by shared memory parallelism, modulated fields and fields with heterogeneous resolution. Galactic propagation is enabled through the implementation of galactic magnetic field models, as well as an efficient forward propagation technique through transformation matrices. To make use of the large Python ecosystem in astrophysics CRPropa 3 can be steered and extended in Python.

  14. Significance of medium energy gamma ray astronomy in the study of cosmic rays

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.; Kniffen, D. A.; Thompson, D. J.; Bignami, G. F.; Cheung, C. Y.

    1975-01-01

    Medium energy (about 10 to 30 MeV) gamma ray astronomy provides information on the product of the galactic electron cosmic ray intensity and the galactic matter to which the electrons are dynamically coupled by the magnetic field. Because high energy (greater than 100 MeV) gamma ray astronomy provides analogous information for the nucleonic cosmic rays and the relevant matter, a comparison between high energy and medium energy gamma ray intensities provides a direct ratio of the cosmic ray electrons and nucleons throughout the galaxy. A calculation of gamma ray production by electron bremsstrahlung shows that: bremsstrahlung energy loss is probably not negligible over the lifetime of the electrons in the galaxy; and the approximate bremsstrahlung calculation often used previously overestimates the gamma ray intensity by about a factor of two. As a specific example, expected medium energy gamma ray intensities are calculated for the speral arm model.

  15. Solidification sensing using high-energy X-ray diffraction

    Microsoft Academic Search

    T. A. Siewert; W. P. Dube; D. W. Fitting

    1996-01-01

    A high-energy transmission X-ray diffraction technique that combines the capabilities of conventional high- and low-energy X-ray systems has been developed at the National Institute of Standards and Technology as a noncontact sensor for locating the liquid\\/solid boundary in metal castings. The high-energy (160 to 320 kV) X-rays can penetrate the thickness of most castings, as well as the mold and

  16. Diffusion of Cosmic-Rays and Gamma-Ray Sources

    NASA Astrophysics Data System (ADS)

    de Cea del Pozo, E.; Torres, D. F.; Marrero, A. Y. Rodríguez

    It is commonly accepted that supernova remnants (SNR) are one of the most probable scenarios of leptonic and hadronic cosmic-ray (CR) acceleration. Such energetic CR can interact with interstellar gas to produce high-energy gamma rays, which can be detected through ground-based air Cherenkov detectors and space telescopes. Here we present a theoretical model that explains the high energy phenomenology of the neighborhood SNR IC 443, as observed with the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescope and the Energetic Gamma-ray Experiment Telescope (EGRET). We interpret MAGIC J0616 + 225 as delayed TeV emission of CR diffusing from IC 443, what naturally explains the displacement between EGRET and MAGIC sources.

  17. Status and future of high energy diffuse gamma-ray astronomy

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.

    1983-01-01

    There are two distinctly different high energy diffuse gamma-ray components, one well correlated with broad galactic features and the other apparently isotropic and presumably extragalactic. The observed diffuse galactic high energy gamma radiation is generally thought to be produced in interactions between the cosmic rays and the interstellar matter and photons. It should then ultimately be possible to obtain from the diffuse galactic emission a detailed picture of the galactic cosmic-ray distribution, a high contrast view of the general structure of the galaxy, and further insight into molecular clouds. Two of the candidates for the explanation of the extragalactic diffuse radiation are the sum of emission from active galaxies and matter-antimatter annihilation. A major advancement in the study of the properties of both galactic and extragalactic gamma radiation should occur over the next decade.

  18. Underground cosmic-ray experiment EMMA

    NASA Astrophysics Data System (ADS)

    Kuusiniemi, P.; Bezrukov, L.; Enqvist, T.; Fynbo, H.; Inzhechik, L.; Joutsenvaara, J.; Kalliokoski, T.; Loo, K.; Lubsandorzhiev, B.; Monto, T.; Petkov, V.; Räihä, T.; Sarkamo, J.; Slupecki, M.; Trzaska, W. H.; Virkajärvi, A.

    2013-02-01

    EMMA (Experiment with MultiMuon Array) is a new approach to study the composition of cosmic rays at the knee region (1 - 10 PeV). The array will measure the multiplicity and lateral distribution of the high-energy muon component of an air shower and its arrival direction on an event-by-event basis. The array operates in the Pyhäsalmi Mine, Finland, at a depth of 75 metres (or 210 m.w.e) corresponding to the cut-off energy of approximately 50 GeV for vertical muons. The data recording with a partial array has started and preliminary results of the first test runs are presented.

  19. High Energy Emission from Gamma Ray Bursts

    SciTech Connect

    Meszaros, P.; Razzaque, S.; Wang, X. Y. [Dept. of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Dept. of Physics, Pennsylvania State University, University Park, PA 16802 (United States)

    2006-07-11

    Gamma-Ray Bursts (GRB) are powerful sources of MeV gamma-rays, whose prompt emission has been detected in some case up to tens of GeV. Leptonic emission mechanisms could produce also TeV gamma-rays, and if proton acceleration takes place, hadronic and photopion processes are expected to produce TeV neutrino emission as well. Current models for the production of GeV-TeV photons and neutrinos are discussed.

  20. Ultrahigh Energy Cosmic Rays from Topological Defects --- Cosmic Strings, Monopoles, Necklaces, and All That

    E-print Network

    Pijushpani Bhattacharjee

    1998-03-03

    The topological defect scenario of origin of the observed highest energy cosmic rays is reviewed. Under a variety of circumstances, topological defects formed in the early Universe can be sources of very massive particles in the Universe today. The decay products of these massive particles may be responsible for the observed highest energy cosmic ray particles above $10^{20}$ eV. Some massive particle production processes involving cosmic strings and magnetic monopoles are discussed. We also discuss the implications of results of certain recent numerical simulations of evolution of cosmic strings. These results (which remain to be confirmed by independent simulations) seem to show that massive particle production may be a generic feature of cosmic strings, which would make cosmic strings an inevitable source of extremely high energy cosmic rays with potentially detectable flux. At the same time, cosmic strings are severely constrained by the observed cosmic ray flux above $10^{20}$ eV, if massive particle radiation is the dominant energy loss mechanism for cosmic strings.

  1. Cosmic Rays from Cygnus X-3

    Microsoft Academic Search

    P. Kevin MacKeown; Trevor C. Weekes

    1985-01-01

    Today many investigators adhere to the idea that cosmic rays receive all their energy from discrete sources with interstellar space acting only as a diffusive medium. An object that accelerates particles to cosmic-ray velocities will almost inevitably produce gamma rays as well. Hence, gamma rays are therefore an effective probe of the source of cosmic radiation even though they account

  2. A study of M31, M87, NGC 253, and M82 in high-energy gamma rays

    NASA Technical Reports Server (NTRS)

    Sreekumar, P.; Bertsch, D. L.; Dingus, B. L.; Esposito, J. A.; Fichtel, C. E.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.; Kniffen, D. A.; Lin, Y. C.

    1994-01-01

    The data from the Energetic Gamma Ray Experiment Telescope (EGRET) all-sky survey are examined for emission from the nearby galaxies M31, M87, NGC 253, and M82 in the high-energy (E greater than MeV) gamma-ray range. No significant emission is observed from any of these galaxies. The derived upper limits for all four galaxies are consistent with that expected from cosmic-ray interactions. For M87, the combination of the high-energy gamma-ray and radio data point to a lower limit of 7 microG for the magnetic field in the disk and 4 microG for the magnetic field in the halo, consistent with equipartition arguments. A study of NGC 253 and M82 show that EGRET observations do not sufficiently constrain the mean cosmic-ray energy density to provide more details on the cosmic-ray distribution in starburst galaxies.

  3. Cosmic Rays and Sunspot Numbers

    NSDL National Science Digital Library

    Susan Higley

    In this activity students analyze and compare two or more graphs to determine if there is a correlation between sunspot number and the variation of cosmic ray flux. They discover that cosmic rays are very energetic particles, mostly protons and electrons, that enter the solar system from the depths of interstellar space and that although the Earth's magnetic field partially shields us from these particles, so too does the much more extended solar wind with its own magnetic field. This is a three-part lesson in which students will construct line graphs displaying the cosmic ray flux and sunspot numbers for a period of time, and then determine if there is a correlation. In order to compare these two sets of data, students will need to scale the data in order to visualize the results. Teacher and student notes for the graphing calculator are included.

  4. Cosmic Rays and Global Warming

    SciTech Connect

    Sloan, T. [Physics Department, University of Lancaster, Lancaster, UK (United Kingdom); Wolfendale, A. W. [Physics Department, Durham University, Durham (United Kingdom)

    2008-01-24

    Some workers have claimed that the observed temporal correlations of (low level) terrestrial cloud cover with the cosmic ray intensity changes, due to solar modulation, are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim in some detail. So far, we have not found any evidence in support and so our conclusions are to doubt it. From the absence of corroborative evidence we estimate that less than 15% at the 95% confidence level, of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 43 years is due to this cause. The origin of the correlation itself is probably the cycle of solar irradiance although there is, as yet, no certainty.

  5. Pionic photons and neutrinos from cosmic ray accelerators

    NASA Astrophysics Data System (ADS)

    Halzen, Francis

    2013-03-01

    Identifying the accelerators that produce the Galactic and extragalactic cosmic rays has been a priority mission of several generations of high energy gamma ray and neutrino telescopes; success has been elusive so far. Detecting the gamma-ray and neutrino fluxes associated with cosmic rays reaches a new watershed with the completion of IceCube, the first neutrino detector with sensitivity to the anticipated fluxes, and the construction of CTA, a ground-based gamma ray detector that will map and study candidate sources with unprecedented precision. In this paper, we revisit the prospects for revealing the sources of the cosmic rays by a multiwavelength approach; after reviewing the methods, we discuss supernova remnants, gamma ray bursts, active galaxies and GZK neutrinos in some detail.

  6. Solar Two High Energy Gamma Ray Observatory

    Microsoft Academic Search

    T. O. Tumer; D. Bhattacharya; M. Chantell; Z. Conner; P. Coppi; C. E. Covault; M. Dragovan; D. T. Gregorich; D. S. Hanna; U. Mohideen; R. A. Ong; S. Oser; K. Ragan; H. Tom; D. A. Williams

    1997-01-01

    The Solar Two Gamma-Ray Telescope is planned as an extension to the STACEE Sandia experiment that is being developed for ground-based gamma-ray astronomy using the atmospheric Cherenkov detection technique in the energy range of 20 to 250 GeV. Because of its large effective light collection area, the STACEE and Solar Two Observatory will be able to reach low energy thresholds

  7. People Interview: Cosmic rays uncover universe theories

    NASA Astrophysics Data System (ADS)

    2012-07-01

    INTERVIEW Cosmic rays uncover universe theories David Smith talks to Paula Chadwick about why she is fascinated by cosmic and gamma rays, and how this is the year that their profile is going to be raised

  8. How Cosmic Rays Affect Learning Objectives

    E-print Network

    Christian, Eric

    1 CRaTER: How Cosmic Rays Affect Humans Learning Objectives: · Students will be able to describe.Ontheground,scientistsfoundthatwhenanastronautsawaflash,acosmicrayhadpassedthroughhiseyeball! Background: more recently, the Italian Space Agency created a similar cosmic ray detector

  9. A New View of the High Energy Gamma-Ray Sky with the Ferrni Gamma-Ray Space Telescope

    NASA Technical Reports Server (NTRS)

    McEnery, Julie

    2009-01-01

    Following its launch in June 2008, high energy gamma-ray observations by the Fermi Gamma-ray Space Telescope have opened a new and important window on a wide variety of phenomena, including pulsars, black holes and active galactic nuclei, gamma-ray bursts, supernova remnants and the origin of cosmic rays, and searches for hypothetical new phenomena such as super symmetric dark matter annihilations. In this talk I will describe the current status of the Fermi observatory and review the science highlights from the first year of observations.

  10. Measuring Cosmic Rays at 1 PeV and Above

    NASA Astrophysics Data System (ADS)

    Rawlins, Katherine

    2012-05-01

    High energy cosmic rays arrive at Earth's upper atmosphere from all directions with a remarkably smooth power-law spectrum. Structures in this otherwise smooth spectrum (such as changes in slope or in chemical composition) give clues as to the sources, acceleration, and propagation of these particles. At energies beyond 1 PeV, as cosmic rays become too rare for direct measurements to be practical, large ground-based experiments make indirect measurements of cosmic ray air showers. They employ a wide range of detection technologies and techniques, exploring known features in the spectrum such as the "knee" and the "ankle", as well as searching for new clues in the energy spectrum, chemical composition, and anisotropy in arrival directions of these particles. This talk will overview the broad landscape of ground-based cosmic ray detector arrays, and will focus on the IceCube Observatory at the South Pole.

  11. Cosmic ray acceleration at modified shocks

    E-print Network

    A. Meli; P. L. Biermann; S. Dimitrakoudis

    2007-08-10

    The non-linear back reaction of accelerated cosmic rays at the shock fronts, leads to the formation of a smooth precursor with a length scale corresponding to the diffusive scale of the energetic particles. Past works claimed that shocklets could be created in the precursor region of a specific shock width, which might energize few thermal particles to sufficient acceleration and furthermore this precursor region may act as confining large angle scatterer for very high energy cosmic rays. On the other hand, it has been shown that the smoothing of the shock front could lower the acceleration efficiency. These controversies motivated us to investigate numerically by Monte Carlo simulations the particle acceleration efficiency in oblique modified shocks. The results show flatter spectra compared to the spectra of the pressumed sharp discontinuity shock fronts. The findings are in accordance with theoretical predictions, since the scattering inside the precursor confines high energy particles to further scattering, resulting in higher energies making the whole acceleration process more efficient.

  12. Nineteenth International Cosmic Ray Conference. HE Sessions, Volume 8

    NASA Technical Reports Server (NTRS)

    Jones, F. C. (compiler)

    1985-01-01

    Papers submitted for presentation at the 19th International Cosmic Ray Conference are compiled. The present volume contains papers addressing high energy interactions and related phenomena. Specific topic areas include muons, neutrinos, magnetic monopoles, nucleon decay, searches for new particles, and acoustic and thermoluminescence detection techniques.

  13. Jodrell Bank and the pursuit of cosmic rays

    NASA Astrophysics Data System (ADS)

    Gunn, A. G.

    Radio astronomy is a subject full of serendipity and coincidence. This paper recounts the strange sequence of incidental events and oversights that led to the establishment of Jodrell Bank as one of radio astronomy's founding institutions. Particular emphasis is given to the purpose for which it was originally intended; the study of high-energy cosmic rays.

  14. Research in cosmic and gamma ray astrophysics

    NASA Technical Reports Server (NTRS)

    Stone, Edward C.; Mewaldt, Richard A.; Prince, Thomas A.

    1992-01-01

    Discussed here is research in cosmic ray and gamma ray astrophysics at the Space Radiation Laboratory (SRL) of the California Institute of Technology. The primary activities discussed involve the development of new instrumentation and techniques for future space flight. In many cases these instrumentation developments were tested in balloon flight instruments designed to conduct new investigations in cosmic ray and gamma ray astrophysics. The results of these investigations are briefly summarized. Specific topics include a quantitative investigation of the solar modulation of cosmic ray protons and helium nuclei, a study of cosmic ray positron and electron spectra in interplanetary and interstellar space, the solar modulation of cosmic rays, an investigation of techniques for the measurement and interpretation of cosmic ray isotopic abundances, and a balloon measurement of the isotopic composition of galactic cosmic ray boron, carbon, and nitrogen.

  15. High energy particle astronomy.

    NASA Technical Reports Server (NTRS)

    Buffington, A.; Muller, R. A.; Smith, L. H.; Smoot, G. F.

    1972-01-01

    Discussion of techniques currently used in high energy particle astronomy for measuring charged and neutral cosmic rays and their isotope and momentum distribution. Derived from methods developed for accelerator experiments in particle physics, these techniques help perform important particle astronomy experiments pertaining to nuclear cosmic ray and gamma ray research, electron and position probes, and antimatter searches.

  16. The impact of networks of robotic telescopes in continuous monitoring of high energy cosmic sources

    NASA Astrophysics Data System (ADS)

    Giovannelli, Franco; Sabau-Graziati, Lola

    High energy (HE) cosmic sources are characterized by emissions in a wide range of the electromagnetic spectrum. In order to clarify their behavior and understand the involved physics it is necessary to perform simultaneous measurements in a range of energy as wide as possible. This makes it necessary to use different techniques and instrumentation both space- and ground-based. Simultaneous observations are in general very difficult to be performed because they need the involvement of many instruments that belong to many experiments under the control of many groups and countries. However, since the importance of multifrequency measurements is now universally recognized, many efforts are made in order to obtain such measurements. Our group has been a pioneer in such a kind of measurements since middle of 1970s. We will briefly discuss the impact of such measurements in different class of HE cosmic sources, such as T Tauri stars (TTSs), active galactic nuclei (AGNs), gamma-ray bursts (GRBs), X-ray binary systems (XRBs), and cataclysmic variables (CVs). This discussion is mainly based on the review paper "The impact of the space experiments on our knowledge of the physics of the universe" tep{GiovannelliSabauGraziati2004} and subsequent revisions. We will also discuss the importance of having a network of robotic telescopes that can provide long term optical monitoring of the classes of HE sources already discussed. Such measurements will provide fundamental data for understanding many problems that are still open, such as the physics of the outbursts in flaring systems, the search of rotational periods of white dwarfs in CVs and orbital periods of those systems, rotational periods and periodicities of flare-like events of TTSs, correlations between optical and X-ray flares in X-ray/Be systems, fluctuations in the light curves of AGNs and their correlations with the HE emission in order to test the validity of current models, etc.

  17. The Cosmic Ray Electron Excess

    NASA Technical Reports Server (NTRS)

    Chang, J.; Adams, J. H.; Ahn, H. S.; Bashindzhagyan, G. L.; Christl, M.; Ganel, O.; Guzik, T. G.; Isbert, J.; Kim, K. C.; Kuznetsov, E. N.; Panasyuk, M. I.; Panov, A. D.; Schmidt, W. K. H.; Seo, E. S.; Sokolskaya, N. V.; Watts, J. W.; Wefel, J. P.; Wu, J.; Zatsepin, V. I.

    2008-01-01

    This slide presentation reviews the possible sources for the apparent excess of Cosmic Ray Electrons. The presentation reviews the Advanced Thin Ionization Calorimeter (ATIC) instrument, the various parts, how cosmic ray electrons are measured, and shows graphs that review the results of the ATIC instrument measurement. A review of Cosmic Ray Electrons models is explored, along with the source candidates. Scenarios for the excess are reviewed: Supernova remnants (SNR) Pulsar Wind nebulae, or Microquasars. Each of these has some problem that mitigates the argument. The last possibility discussed is Dark Matter. The Anti-Matter Exploration and Light-nuclei Astrophysics (PAMELA) mission is to search for evidence of annihilations of dark matter particles, to search for anti-nuclei, to test cosmic-ray propagation models, and to measure electron and positron spectra. There are slides explaining the results of Pamela and how to compare these with those of the ATIC experiment. Dark matter annihilation is then reviewed, which represent two types of dark matter: Neutralinos, and kaluza-Kline (KK) particles, which are next explained. The future astrophysical measurements, those from GLAST LAT, the Alpha Magnetic Spectrometer (AMS), and HEPCAT are reviewed, in light of assisting in finding an explanation for the observed excess. Also the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) could help by revealing if there are extra dimensions.

  18. Cosmic-ray sum rules

    SciTech Connect

    Frandsen, Mads T. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Masina, Isabella [Dip. di Fisica dell'Universita di Ferrara and INFN Sez. di Ferrara, Via Saragat 1, I-44100 Ferrara (Italy); CP3-Origins, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark); Sannino, Francesco [CP3-Origins, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark)

    2011-06-15

    We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays; we show how they can be used to predict the positron fraction at energies not yet explored by current experiments, and to constrain specific models.

  19. The future of high energy gamma ray astronomy and its potential astrophysical implications

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.

    1982-01-01

    Future satellites should carry instruments having over an order of magnitude greater sensitivity than those flown thus far as well as improved energy and angular resolution. The information to be obtained from these experiments should greatly enhance knowledge of: the very energetic and nuclear processes associated with compact objects; the structure of our galaxy; the origin and dynamic pressure effects of the cosmic rays; the high energy particles and energetic processes in other galaxies; and the degree of matter-antimatter symmetry of the universe. The relevant aspects of extragalactic gamma ray phenomena are emphasized along with the instruments planned. The high energy gamma ray results of forthcoming programs such as GAMMA-1 and the Gamma Ray Observatory should justify even more sophisticated telescopes. These advanced instruments might be placed on the space station currently being considered by NASA.

  20. A cosmic ray hodoscope system

    E-print Network

    Cantrell, Wallace Gene

    1965-01-01

    A COSMIC EAY HODOSCOPE SYSTEM A Thesis By Wallace Gene Cantrell Submitted to the Graduate College of the Texas A&M University in Partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1965 Major Sub)ect: Physics A... COSMIC RAY HODOSCOPE SYSTEM A Thesis By Wa11ace Gene Cantrell Approved as to style and content by: , V ( Chairman of Committee H, ad of Depar men Zaire Member of Committee ~m i1558 Table of Contents Page Introduction Geometry of the Detector...

  1. Very-High Energy Gamma-Ray Astronomy: A 23-Year Success Story in Astroparticle Physics

    NASA Astrophysics Data System (ADS)

    Lorenz, Eckart; Wagner, Robert

    Very high energy (VHE) gamma quanta contribute only to a minuscule fraction - below one per million - to the flux of cosmic rays. Nevertheless, being neutral particles they are currently the best "messengers" of processes from the relativistic/ultra-relativistic Universe because they can be extrapolated back to their origin. The window of VHE gamma rays was opened only in 1989 by the Whipple collaboration, reporting the observation of TeV gamma rays from the Crab nebula. After a slow start, this new field of research is now rapidly expanding with the discovery of more than 150 VHE gamma-ray emitting sources. Progress is intimately related with the steady improvement of detectors and rapidly increasing computing power. We give an overview of the early attempts before and around 1989 and the progress after the pioneering work of the Whipple collaboration. Before describing the important experiments that paved the way towards the current observations, a short review of gamma rays as cosmic messengers and the general concept of detecting and filtering them from the vast majority of charged cosmic rays will be given in the introduction. The main part of the chapter on VHE gamma-ray astronomy highlights the various experiments that have pushed the field to the current success. At the end, a short overview of the challenging physics questions will be given summarizing the goals of the experiments in order to give a coherent picture of the underlying reasons behind the experiments. In coherence with the energy range of cosmic rays observable from Earth, we will set the lower energy limit to about 30 GeV above which ground-based observations with the most powerful instruments are now possible. Below this energy range observations can only be performed with balloon or satellite-borne detectors. Their detection range is below the classical cosmic-ray energy range.

  2. An absence of neutrinos associated with cosmic-ray acceleration in ?-ray bursts.

    PubMed

    2012-04-19

    Very energetic astrophysical events are required to accelerate cosmic rays to above 10(18)?electronvolts. GRBs (?-ray bursts) have been proposed as possible candidate sources. In the GRB 'fireball' model, cosmic-ray acceleration should be accompanied by neutrinos produced in the decay of charged pions created in interactions between the high-energy cosmic-ray protons and ?-rays. Previous searches for such neutrinos found none, but the constraints were weak because the sensitivity was at best approximately equal to the predicted flux. Here we report an upper limit on the flux of energetic neutrinos associated with GRBs that is at least a factor of 3.7 below the predictions. This implies either that GRBs are not the only sources of cosmic rays with energies exceeding 10(18)?electronvolts or that the efficiency of neutrino production is much lower than has been predicted. PMID:22517161

  3. An absence of neutrinos associated with cosmic-ray acceleration in ?-ray bursts

    NASA Astrophysics Data System (ADS)

    Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Altmann, D.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K.-H.; Bell, M.; Benabderrahmane, M. L.; Benzvi, S.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Bose, D.; Böser, S.; Botner, O.; Brayeur, L.; Brown, A. M.; Buitink, S.; Caballero-Mora, K. S.; Carson, M.; Casier, M.; Chirkin, D.; Christy, B.; Clevermann, F.; Cohen, S.; Colnard, C.; Cowen, D. F.; Cruz Silva, A. H.; D'Agostino, M. V.; Danninger, M.; Daughhetee, J.; Davis, J. C.; de Clercq, C.; Degner, T.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; Deyoung, T.; Díaz-Vélez, J. C.; Dierckxsens, M.; Dreyer, J.; Dumm, J. P.; Dunkman, M.; Eisch, J.; Ellsworth, R. W.; Engdegård, O.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Fedynitch, A.; Feintzeig, J.; Feusels, T.; Filimonov, K.; Finley, C.; Fischer-Wasels, T.; Flis, S.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Gladstone, L.; Glüsenkamp, T.; Goldschmidt, A.; Goodman, J. A.; Góra, D.; Grant, D.; Griesel, T.; Groß, A.; Grullon, S.; Gurtner, M.; Ha, C.; Haj Ismail, A.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Heereman, D.; Heinen, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Hoffmann, B.; Homeier, A.; Hoshina, K.; Huelsnitz, W.; Hül?, J.-P.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Ishihara, A.; Jacobi, E.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Kappes, A.; Karg, T.; Karle, A.; Kiryluk, J.; Kislat, F.; Klein, S. R.; Köhne, J.-H.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Kroll, G.; Kunnen, J.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Laihem, K.; Landsman, H.; Larson, M. J.; Lauer, R.; Lünemann, J.; Madsen, J.; Marotta, A.; Maruyama, R.; Mase, K.; Matis, H. S.; Meagher, K.; Merck, M.; Mészáros, P.; Meures, T.; Miarecki, S.; Middell, E.; Milke, N.; Miller, J.; Montaruli, T.; Morse, R.; Movit, S. M.; Nahnhauer, R.; Nam, J. W.; Naumann, U.; Nowicki, S. C.; Nygren, D. R.; Odrowski, S.; Olivas, A.; Olivo, M.; O'Murchadha, A.; Panknin, S.; Paul, L.; Pérez de Los Heros, C.; Piegsa, A.; Pieloth, D.; Posselt, J.; Price, P. B.; Przybylski, G. T.; Rawlins, K.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Richman, M.; Riedel, B.; Rizzo, A.; Rodrigues, J. P.; Rothmaier, F.; Rott, C.; Ruhe, T.; Rutledge, D.; Ruzybayev, B.; Ryckbosch, D.; Sander, H.-G.; Santander, M.; Sarkar, S.; Schatto, K.; Schmidt, T.; Schöneberg, S.; Schönwald, A.; Schukraft, A.; Schulte, L.; Schultes, A.; Schulz, O.; Schunck, M.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Smith, M. W. E.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strahler, E. A.; Ström, R.; Stüer, M.; Sullivan, G. W.; Taavola, H.; Taboada, I.; Tamburro, A.; Ter-Antonyan, S.; Tilav, S.; Toale, P. A.; Toscano, S.; Tosi, D.; van Eijndhoven, N.; van Overloop, A.; van Santen, J.; Vehring, M.; Voge, M.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Walter, M.; Wasserman, R.; Weaver, Ch.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, C.; Xu, D. L.; Xu, X. W.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; Zoll, M.; IceCube Collaboration

    2012-04-01

    Very energetic astrophysical events are required to accelerate cosmic rays to above 1018electronvolts. GRBs (?-ray bursts) have been proposed as possible candidate sources. In the GRB `fireball' model, cosmic-ray acceleration should be accompanied by neutrinos produced in the decay of charged pions created in interactions between the high-energy cosmic-ray protons and ?-rays. Previous searches for such neutrinos found none, but the constraints were weak because the sensitivity was at best approximately equal to the predicted flux. Here we report an upper limit on the flux of energetic neutrinos associated with GRBs that is at least a factor of 3.7 below the predictions. This implies either that GRBs are not the only sources of cosmic rays with energies exceeding 1018electronvolts or that the efficiency of neutrino production is much lower than has been predicted.

  4. Geometry of an interplanetary CME on October 29, 2003 deduced from cosmic rays

    Microsoft Academic Search

    T. Kuwabara; K. Munakata; S. Yasue; C. Kato; S. Akahane; M. Koyama; J. W. Bieber; P. Evenson; R. Pyle; Z. Fujii; M. Tokumaru; M. Kojima; K. Marubashi; M. L. Duldig; J. E. Humble; M. R. Silva; N. B. Trivedi; W. D. Gonzalez; N. J. Schuch

    2004-01-01

    A coronal mass ejection (CME) associated with an X17 solar flare reached Earth on October 29, 2003, causing an ~11% decrease in the intensity of high-energy Galactic cosmic rays recorded by muon detectors. The CME also produced a strong enhancement of the cosmic ray directional anisotropy. Based upon a simple inclined cylinder model, we use the anisotropy data to derive

  5. Isotopic composition of primary cosmic rays H-Fe for ISEE-C

    NASA Technical Reports Server (NTRS)

    Heckman, H. H.

    1984-01-01

    The high energy cosmic ray instrument built for the International Sun-Earth Explorer is described. Some aspects of that system are critically renewed so that the experience gained in the design, construction and operation of this experiment can serve as a guide in designing future cosmic ray particle identification systems.

  6. Energy Estimation of UHE Cosmic Rays using the Atmospheric Fluorescence Technique

    E-print Network

    C. Song; Z. Cao; B. R. Dawson; B. E. Fick; P. Sokolsky; X. Zhang

    1999-12-22

    We use the CORSIKA air shower simulation program to review the method for assigning energies to ultra-high energy (UHE) cosmic rays viewed with the air fluorescence technique. This technique uses the atmosphere as a calorimeter, and we determine the corrections that must be made to the calorimetric energy to yield the primary cosmic ray energy.

  7. Cosmic ray acceleration in supernova remnants and the FERMI\\/PAMELA data

    Microsoft Academic Search

    Markus Ahlers; Philipp Mertsch; Subir Sarkar

    2009-01-01

    We discuss recent observations of high energy cosmic ray positrons and electrons in the context of hadronic interactions in supernova remnants (SNRs), the suspected accelerators of galactic cosmic rays. Diffusive shock acceleration can harden the energy spectrum of secondary positrons relative to that of the primary protons and electrons and thus explain the rise in the positron fraction observed by

  8. Cosmic Ray "Knee": A Herald of New Physics?

    E-print Network

    D. Kazanas; A. Nicolaidis

    2001-09-26

    We propose that the knee in the cosmic ray spectrum at energies E ~ 10^{15.5} eV is due to "new physics", namely to a channel in the high energy (~ TeV in the CM) proton interactions hitherto unaccounted for in estimating the energies of the air shower cosmic rays. The new interaction transfers part of the primary particle's energy to modes which do not trigger the experimental arragement (neutrinos, lightest supersymmetric particle, gravitons) thus underestimating its true energy. We show that this underestimate leads naturally to the observed break (the "knee") in the inferred cosmic ray spectrum. The suggestion we advance fits nicely to current theoretical extensions of the Standard Model (supersymmetry, technicolor, low scale gravity) where new physics at the TeV scale manifests with the distinct signature of missing energy. We present a simple model where the new physics proceeds via gluon fusion and assuming a single power law for the galactic (E ~ 10^{18.5} eV) cosmic ray spectrum, we produce a good fit to the data in the 10^{14}-10^{18.5} eV range. Our proposal should be testable in laboratory experiments (LHC) in the near future and, should it be proven correct, it would signal besides the presence of new physics in high energy interactions, a drastically different interpretation of the sources and acceleration of cosmic rays.

  9. Discovery of High-energy and Very High Energy ?-Ray Emission from the Blazar RBS 0413

    NASA Astrophysics Data System (ADS)

    Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Beilicke, M.; Benbow, W.; Böttcher, M.; Bouvier, A.; Bradbury, S. M.; Buckley, J. H.; Bugaev, V.; Byrum, K.; Cannon, A.; Cesarini, A.; Ciupik, L.; Collins-Hughes, E.; Connolly, M. P.; Coppi, P.; Cui, W.; Decerprit, G.; Dickherber, R.; Dumm, J.; Errando, M.; Falcone, A.; Feng, Q.; Finley, J. P.; Finnegan, G.; Fortson, L.; Furniss, A.; Galante, N.; Gall, D.; Godambe, S.; Griffin, S.; Grube, J.; Gyuk, G.; Hanna, D.; Hawkins, K.; Holder, J.; Huan, H.; Hughes, G.; Humensky, T. B.; Kaaret, P.; Karlsson, N.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krawczynski, H.; Krennrich, F.; Lang, M. J.; Lee, K.; Madhavan, A. S.; Maier, G.; Majumdar, P.; McArthur, S.; McCann, A.; Moriarty, P.; Mukherjee, R.; Ong, R. A.; Orr, M.; Otte, A. N.; Palma, N.; Park, N.; Perkins, J. S.; Pichel, A.; Pohl, M.; Prokoph, H.; Quinn, J.; Ragan, K.; Reyes, L. C.; Reynolds, P. T.; Roache, E.; Rose, H. J.; Ruppel, J.; Saxon, D. B.; Schroedter, M.; Sembroski, G. H.; ?entürk, G. D.; Smith, A. W.; Staszak, D.; Telezhinsky, I.; Teši?, G.; Theiling, M.; Thibadeau, S.; Tsurusaki, K.; Varlotta, A.; Vivier, M.; Wakely, S. P.; Ward, J. E.; Weekes, T. C.; Weinstein, A.; Weisgarber, T.; Williams, D. A.; Zitzer, B.; Fortin, P.; Horan, D.

    2012-05-01

    We report on the discovery of high-energy (HE; E > 0.1 GeV) and very high energy (VHE; E > 100 GeV) ?-ray emission from the high-frequency-peaked BL Lac object RBS 0413. VERITAS, a ground-based ?-ray observatory, detected VHE ? rays from RBS 0413 with a statistical significance of 5.5 standard deviations (?) and a ?-ray flux of (1.5 ± 0.6stat ± 0.7syst) × 10-8 photons m-2 s-1 (~1% of the Crab Nebula flux) above 250 GeV. The observed spectrum can be described by a power law with a photon index of 3.18 ± 0.68stat ± 0.30syst. Contemporaneous observations with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope detected HE ? rays from RBS 0413 with a statistical significance of more than 9?, a power-law photon index of 1.57 ± 0.12stat +0.11 - 0.12sys, and a ?-ray flux between 300 MeV and 300 GeV of (1.64 ± 0.43stat +0.31 - 0.22sys) × 10-5 photons m-2 s-1. We present the results from Fermi-LAT and VERITAS, including a spectral energy distribution modeling of the ?-ray, quasi-simultaneous X-ray (Swift-XRT), ultraviolet (Swift-UVOT), and R-band optical (MDM) data. We find that, if conditions close to equipartition are required, both the combined synchrotron self-Compton/external-Compton and the lepto-hadronic models are preferred over a pure synchrotron self-Compton model.

  10. Fractional diffusion of cosmic rays

    E-print Network

    A. A. Lagutin; V. V. Uchaikin

    2001-07-13

    We consider the propagation of galactic cosmic rays under assumption that the interstellar medium is a fractal one. An anomalous diffusion equation in terms of fractional derivatives is used to describe of cosmic ray propagation. The anomaly in used model results from large free paths ("Levy flights") of particles between galactic inhomogeneities and long time a particle stays in a trap. An asymptotical solution of the anomalous diffusion equation for point instantaneous and impulse sources with inverse power spectrum relating to supernova bursts is found. It covers both subdiffusive and superdiffusive regimes and is expressed in terms of the stable distributions. The energy dependence of spectral exponent of observed particles in different regimes is discussed.

  11. Cosmic-Ray Anisotropy with the HAWC Observatory

    NASA Astrophysics Data System (ADS)

    Fiorino, Daniel

    2014-03-01

    The High-Altitude Water Cherenkov (HAWC) Observatory is a TeV gamma-ray and cosmic-ray detector operating at an altitude of 4100 meters in Mexico. HAWC is an extensive air-shower array. Upon completion in 2014, it will comprise 300 optically-isolated water-Cherenkov detectors. While the observatory is only partially deployed, with ~ 100 Cherenkov detectors in data acquisition since summer 2013, statistics are sufficient to perform studies of cosmic-ray anisotropy. We discuss the status and performance of the detector, including the pointing accuracy and angular resolution as inferred from the observation of the moon shadow and simulations, and present new results on small-scale cosmic-ray anisotropy from our ever-growing detector and dataset. We acknowledge the support of US NSF; US DOE Office of High-Energy Physics; The Laboratory Directed Research and Development (LDRD) program of Los Alamos National Lab; The Wisconsin Alumni Research Foundation.

  12. Nineteenth International Cosmic Ray Conference. Conference Papers: Invited Rapporteur, Highlight, Miscellaneous, Volume 9

    NASA Technical Reports Server (NTRS)

    Jones, F. C. (compiler)

    1986-01-01

    Invited talks, rapporteur talks, and highlight talks are included. Topics of the invited and highlight talks include astrophysical jets, gamma-ray line astronomy, cosmic rays and gamma rays in astrophysics, the early universe, elementary particle physics, solar flares and acceleration of energetic particles, cosmogenic nuclei, extragalactic astronomy, composition of solar flare particles, very high energy gamma ray sources, gamma-ray bursts, shock acceleration in the solar wind, cosmic rays in deep underground detectors, spectrum of cosmic rays at 10 to the 19th power eV, and nucleus-nucleus interactions.

  13. Cosmic ray penetration in diffuse clouds

    NASA Astrophysics Data System (ADS)

    Morlino, G.; Gabici, S.

    2015-07-01

    Cosmic rays are a fundamental source of ionization for molecular and diffuse clouds, influencing their chemical, thermal, and dynamical evolution. The amount of cosmic rays inside a cloud also determines the gamma-ray flux produced by hadronic collisions between cosmic rays and cloud material. We study the spectrum of cosmic rays inside and outside of a diffuse cloud by solving the stationary transport equation for cosmic rays including diffusion, advection, and energy losses due to ionization of neutral hydrogen atoms. We found that the cosmic ray spectrum inside a diffuse cloud differs from the one in the interstellar medium (ISM) for energies smaller than Ebr ? 100 MeV, irrespective of the model details. Below Ebr, the spectrum is harder (softer) than that in the ISM if the latter is a power law ?p-s with s larger (smaller) than ˜0.42.

  14. Cosmic ray penetration in diffuse clouds

    E-print Network

    Morlino, G

    2015-01-01

    Cosmic rays are a fundamental source of ionization for molecular and diffuse clouds, influencing their chemical, thermal, and dynamical evolution. The amount of cosmic rays inside a cloud also determines the $\\gamma$-ray flux produced by hadronic collisions between cosmic rays and cloud material. We study the spectrum of cosmic rays inside and outside of a diffuse cloud, by solving the stationary transport equation for cosmic rays including diffusion, advection and energy losses due to ionization of neutral hydrogen atoms. We found that the cosmic ray spectrum inside a diffuse cloud differs from the one in the interstellar medium for energies smaller than $E_{br}\\approx 100$ MeV, irrespective of the model details. Below $E_{br}$, the spectrum is harder (softer) than that in the interstellar medium if the latter is a power law $\\propto p^{-s}$ with $s$ larger (smaller) than $\\sim0.42$.

  15. High-Energy Cosmology: gamma rays and neutrinos from beyond the galaxy

    E-print Network

    Charles D. Dermer

    2006-11-06

    Our knowledge of the high-energy universe is undergoing a period of rapid change as new astronomical detectors of high-energy radiation start to operate at their design sensitivities. Now is a boomtime for high-energy astrophysics, with new discoveries from Swift and HESS, results from MAGIC and VERITAS starting to be reported, the upcoming launches of the gamma-ray space telescopes GLAST and AGILE, and anticipated data releases from IceCube and Auger. A formalism for calculating statistical properties of cosmological gamma-ray sources is presented. Application is made to model calculations of the statistical distributions of gamma-ray and neutrino emission from (i) beamed sources, specifically, long-duration GRBs, blazars, and extagalactic microquasars, and (ii) unbeamed sources, including normal galaxies, starburst galaxies and clusters. Expressions for the integrated intensities of faint beamed and unbeamed high-energy radiation sources are also derived. A toy model for the background intensity of radiation from dark-matter annihilation taking place in the early universe is constructed. Estimates for the gamma-ray fluxes of local group galaxies, starburst, and infrared luminous galaxies are briefly reviewed. Because the brightest extragalactic gamma-ray sources are flaring sources, and these are the best targets for sources of PeV -- EeV neutrinos and ultra-high energy cosmic rays, rapidly slewing all-sky telescopes like MAGIC and an all-sky gamma-ray observatory beyond Milagro will be crucial for optimal science return in the multi-messenger age.

  16. The isotopic composition of cosmic-ray beryllium and its implication for the cosmic ray's age

    NASA Technical Reports Server (NTRS)

    Lukasiak, A.; Ferrando, P.; Mcdonald, F. B.; Webber, W. R.

    1994-01-01

    We report a new measurement of the cosmic-ray isotopic composition of beryllium in the low-energy range from 35 to 113 MeV per nucleon. This measurement was made using the High Energy Telescope of the CRS experiment on the Voyager 1 and 2 spacecraft during the time period from 1977 to 1991. In this overall time period of 14 years the average solar modulation level was about 500 MV. The cosmic-ray beryllium isotopes were completely separated with an average mass resolution sigma of 0.185 amu. The isotope fractions of Be-7, Be-9, and Be-10 obtained are 52.4 +/- 2.9%, 43.3 +/- 3.7%, and 4.3 +/- 1.5%, respectively. The measured cosmic-ray abundances of Be-7 and Be-9 are found to be in agreement with calculations based on standard Leaky-Box model for the interstellar propagation of cosmic-ray nuclei using the recent cross sections of the New Mexico-Saclay collaboration. From our observed ratio Be-10/Be = 4.3 +/- 1.5% we deduce an average interstellar density of about 0.28 (+0.14, -0.11) atoms/cu cm, and acosmic-ray lifetime for escape of 27 (+19, -9) x 10(exp 6) years. The surviving fraction of Be-10 is found to be 0.19 +/- 0.07. Modifications to the conclusions of the Leaky-Box model when a diffusion + convection halo model for propagation is used are also considered.

  17. Relativistic cosmic rays and corotating interaction regions

    SciTech Connect

    Duggal, S.P.; Tsurutani, B.T.; Pomerantz, M.A.; Tsao, C.H.; Smith, E.J.

    1981-09-01

    Analyses of relativistic galactic cosmic ray intensity variations have been conducted to determine the nature of the modulations that are related to the presence of corotating interaction regions (CIR) in interplanetary space. The corotating interaction regions have been identified from the plasma and field observations recorded by Pioneer 10 and 11 spacecrafts during the period 1972--1974. This investigation has established that the nucleonic intensity recorded at the polar stations Thule and McMurdo decreases as the streams associated with the CIR overtake the earth. However, this modulation occurs only for those CIR-associated streams in which a neutral sheet is imbedded. In contrast, geomagnetic storms are related to CIR streams with or without neutral sheets. Taken together, these results suggest that the ostensible effect of CIR'S on the intensity of high-energy particles is primarily a consequence of drifts related to neutral sheets, although diffusion effects cannot be ruled out at this stage.

  18. A New View of the High Energy Gamma-Ray Sky with the Fermi Gamma-Ray Space Telescope

    NASA Astrophysics Data System (ADS)

    McEnery, Julie E.

    2011-01-01

    Following its launch in June 2008, high-energy gamma-ray observations by the Fermi Gamma-ray Space Telescope have unveiled over 1000 new sources and opened an important and previously unexplored window on a wide variety of phenomena. These have included the discovery of an population of pulsars pulsing only in gamma rays; the detection of photons up to 10s of GeV from gamma-ray bursts, enhancing our understanding of the astrophysics of these powerful explosions; the detection of hundreds of active galaxies; a measurement of the high energy cosmic-ray electron spectrum which may imply the presence of nearby astrophysical particle accelerators; the determination of the diffuse gamma-ray emission with unprecedented accuracy and the constraints on phenomena such as supersymmetric dark-matter annihilations and exotic relics from the Big Bang. Continuous monitoring of the high-energy gamma-ray sky has uncovered numerous outbursts from active galaxies and the discovery of transient sources in our galaxy. In this talk I will describe the current status of the Fermi observatory and review the science highlights from Fermi.

  19. Solidification sensing using high-energy X-ray diffraction

    SciTech Connect

    Siewert, T.A.; Dube, W.P.; Fitting, D.W. [National Inst. of Standards and Technology, Boulder, CO (United States)

    1996-07-01

    A high-energy transmission X-ray diffraction technique that combines the capabilities of conventional high- and low-energy X-ray systems has been developed at the National Institute of Standards and Technology as a noncontact sensor for locating the liquid/solid boundary in metal castings. The high-energy (160 to 320 kV) X-rays can penetrate the thickness of most castings, as well as the mold and furnace walls. One practical goal for this new method is to collect data on the position, velocity, and possibly the shape of the solidification front of directionally solidified castings. Such information is vital for development and verification of improved solidification models, but it has been difficult to gather because of high temperatures, strong magnetic fields, and vacuum casting furnaces.

  20. The photodisintegration of cosmic ray nuclei by solar photons: the Gerasimova-Zatsepin effect revisted

    E-print Network

    Gustavo Medina Tanco; Alan A. Watson

    1998-10-14

    The interesting possibility of measuring the masses of high energy cosmic ray particles by observing pairs of extensive air showers arriving at the earth nearly simultaneously was proposed some years ago by Gerasimova and Zatsepin (1960). Such showers would be created by the nuclear fragments originating as a result of the photodisintegration of massive nuclei interacting with the solar radiation field. In this paper we re-visit this possibility in the context of existing and proposed detectors of high and ultra-high energy cosmic rays considering a simple, yet realistic, model of the interplanetary magnetic field. The possibilty of observing the mass fragmentation of cosmic rays directly, however, remains challenging.

  1. Measurement of C-12, O-16, and Fe-56 charge changing cross sections in helium at high energy, comparison with cross sections in hydrogen, and application to cosmic-ray propagation

    NASA Technical Reports Server (NTRS)

    Ferrando, P.; Webber, W. R.; Goret, P.; Kish, J. C.; Schrier, D. A.; Soutoul, A.; Testard, O.

    1988-01-01

    We present measurements of the spallation cross sections of carbon, oxygen, and iron in helium and hydrogen, at beam energies from 540 to 1600 MeV/nucleon, performed by exposing liquid helium, CH2, and C targets. Charge changing cross sections are reported for fragments down to Ne for Fe + alpha and Fe + p reactions, and down to B for O + alpha, O + p, C + alpha, and C + p reactions. Alpha- to p-induced cross section ratios (sigma(sub alpha)/sigma(sub p)) are determined at the same energy per nucleon. From these measurements an empirical formula for the (sigma(sub alpha)/sigma(sub p)) ratios is derived and is found in good agreement with available isotopic cross sections data from radioactivity and radiochemical techniques. These results are applied to the propagation of heavy charged cosmic rays in an interstellar medium with a helium to hydrogen abundance ratio of 0.10. It is shown that the Sc-Mn/Fe ratio prediction is decreased relative to the B/C ratio when compared to propagation calculations in a pure hydrogen interstellar medium.

  2. Imaging large vessels using cosmic-ray muon energy-loss techniques

    Microsoft Academic Search

    P. M. Jenneson; W. B. Gilboy; S. J. R. Simons; S. J. Stanley; D. Rhodes

    2007-01-01

    Imaging the internal structure of large vessels (2–20m in diameter) is not possible with most traditional imaging methods. The sheer size renders gamma-ray and other high-energy photon, neutron, electrical and acoustic techniques useless, whilst the use of high-energy accelerators required to produce charged-particles of sufficient energy are impractical in most industrial situations. The use of naturally occurring high-energy (?GeV) cosmic-ray

  3. Light Element Evolution and Cosmic Ray Energetics

    E-print Network

    R. Ramaty; S. T. Scully; R. E. Lingenfelter; B. Kozlovsky

    1999-09-01

    Using cosmic-ray energetics as a discriminator, we investigate evolutionary models of LiBeB. We employ a Monte Carlo code which incorporates the delayed mixing into the ISM both of the synthesized Fe, due to its incorporation into high velocity dust grains, and of the cosmic-ray produced LiBeB, due to the transport of the cosmic rays. We normalize the LiBeB production to the integral energy imparted to cosmic rays per supernova. Models in which the cosmic rays are accelerated mainly out of the average ISM significantly under predict the measured Be abundance of the early Galaxy, the increase in [O/Fe] with decreasing [Fe/H] notwithstanding. We suggest that this increase could be due to the delayed mixing of the Fe. But, if the cosmic-ray metals are accelerated out of supernova ejecta enriched superbubbles, the measured Be abundances are consistent with a cosmic-ray acceleration efficiency that is in very good agreement with the current epoch data. We also find that neither the above cosmic-ray origin models nor a model employing low energy cosmic rays originating from the supernovae of only very massive progenitors can account for the $^6$Li data at values of [Fe/H] below $-$2.

  4. A hysteresis effect in cosmic ray modulation

    NASA Technical Reports Server (NTRS)

    Verschell, H. J.; Mendell, R. B.; Korff, S. A.

    1974-01-01

    The rigidity dependence is investigated in the modulation of cosmic ray protons and alphas at intermediate (2-13 Gv) rigidities during the declines and recoveries of the cosmic ray flux near cosmic ray minimum. The results include the finding that sudden changes in the modulation of the primary cosmic rays are initiated by large solar particle outflow and begin as type I Forbush decreases. Typically, the modulation spectrum becomes flatter at intermediate rigidity below 13 Gv and steeper at rigidities above 13 Gv during early recovery.

  5. Propagation of cosmic rays in the galaxy

    NASA Technical Reports Server (NTRS)

    Daniel, R. R.; Stephens, S. A.

    1974-01-01

    The characteristics of a model for analyzing the propagation of cosmic rays are discussed. The requirements for analyzing the relevant observational data on cosmic rays are defines as: (1) the chemical and isotopic composition of cosmic rays as a function of energy, (2) the flux and energy spectrum of the individual nucleonic components, (3) the flux and energy spectrum of the electronic component, (4) the cosmic ray prehistory, and (5) the degree of isotropy in their arrival directions as a function of energy. It is stated that the model which has been able to bring to pass the greatest measure of success is the galactic confinement model.

  6. Origin and propagation of the highest energy cosmic rays

    E-print Network

    R. J. Protheroe

    1996-12-22

    In this lecture I give an overview of shock acceleration, interactions of high energy cosmic rays with, and propagation through, the background radiation, and the resulting electron-photon cascade. I argue that while the origin of the highest energy cosmic rays is still uncertain, it is not necessary to invoke exotic models such as emission by topological defects to explain the existing data. It seems likely that shock acceleration at Fanaroff-Riley Class II radio galaxies can account for the existing data. However, new cosmic ray data, as well as better estimates of the extragalactic radiation fields and magnetic fields will be necessary before we will be certain of the origin of the highest energy particles occurring in nature.

  7. Very-high energy gamma-ray astronomy. A 23-year success story in high-energy astroparticle physics

    NASA Astrophysics Data System (ADS)

    Lorenz, E.; Wagner, R.

    2012-08-01

    Very-high energy (VHE) gamma quanta contribute only a minuscule fraction - below one per million - to the flux of cosmic rays. Nevertheless, being neutral particles they are currently the best "messengers" of processes from the relativistic/ultra-relativistic Universe because they can be extrapolated back to their origin. The window of VHE gamma rays was opened only in 1989 by the Whipple collaboration, reporting the observation of TeV gamma rays from the Crab nebula. After a slow start, this new field of research is now rapidly expanding with the discovery of more than 150 VHE gamma-ray emitting sources. Progress is intimately related with the steady improvement of detectors and rapidly increasing computing power. We give an overview of the early attempts before and around 1989 and the progress after the pioneering work of the Whipple collaboration. The main focus of this article is on the development of experimental techniques for Earth-bound gamma-ray detectors; consequently, more emphasis is given to those experiments that made an initial breakthrough rather than to the successors which often had and have a similar (sometimes even higher) scientific output as the pioneering experiments. The considered energy threshold is about 30 GeV. At lower energies, observations can presently only be performed with balloon or satellite-borne detectors. Irrespective of the stormy experimental progress, the success story could not have been called a success story without a broad scientific output. Therefore we conclude this article with a summary of the scientific rationales and main results achieved over the last two decades.

  8. Radiation processing with high-energy X-rays

    NASA Astrophysics Data System (ADS)

    Cleland, Marshall R.; Stichelbaut, Frédéric

    2013-03-01

    The radiation processing of materials and commercial products with high-energy X-rays, which are also identified by the German term bremsstrahlung, can produce beneficial changes that are similar to those obtained by irradiation with nuclear gamma rays emitted by cobalt-60 sources. Both X-rays and gamma rays are electromagnetic radiations with short wavelengths and high photon energies that can stimulate chemical reactions by creating ions and free radicals in irradiated materials. Nevertheless, there are some physical differences in these energy sources that can influence the choice for practical applications. The English translation of bremsstrahlung is braking radiatiorn or deceleration radiation. It is produced when energetic electrons are deflected by the strong electric field near an atomic nucleus. The efficiency for producing this kind of electromagnetic energy increases with the kinetic energy of the electrons and the atomic number of the target material. The energy spectrum of the emitted X-ray photons is very broad and extends up to the maximum energy of the incident electrons. In contrast, a cobalt-60 nucleus emits two gamma rays simultaneously, which have well-defined energies. Another significant difference is the angular distribution of the radiation. Nuclear gamma rays are emitted in all directions, but high-energy bremsstrahlung photons are concentrated in the direction of the incident electrons when they strike the target material. This property enables an X-ray processing facility to be more compact than a gamma-ray processing facility with similar throughput capacity, and it increases the penetration and the efficiency for absorbing the emitted X-ray energy in the irradiated material. Recent increases in the electron energy and the electron beam power from modern industrial accelerators have increased the throughput rates in X-ray processing facilities, so that this irradiation method is now economically competitive with large cobalt-60 facilities. Several industrial facilities are now equipped to provide radiation processing with X-rays. This paper describes the characteristics of high-energy, high-power X-rays, and some practical applications in curing polymeric materials with this kind of radiation.

  9. The Milky Way in Very High Energy Gamma-Ray Light

    E-print Network

    Adelaide, University of

    The Milky Way in Very High Energy Gamma-Ray Light 2511 Gamma-Ray Light: What is it? Detecting Very High Energy Gamma-Rays with the H.E.S.S. Gamma-Ray Telescopes The Milky Way in Very High Energy Gamma-Ray Light Weaver etal 1977 (also Swift src 5) 2 prob. 7.0x10-1 Note size of car! Very High Energy Gamma-Rays

  10. Cosmic-ray neutron simulations and measurements in Taiwan.

    PubMed

    Chen, Wei-Lin; Jiang, Shiang-Huei; Sheu, Rong-Jiun

    2014-10-01

    This study used simulations of galactic cosmic ray in the atmosphere to investigate the neutron background environment in Taiwan, emphasising its altitude dependence and spectrum variation near interfaces. The calculated results were analysed and compared with two measurements. The first measurement was a mobile neutron survey from sea level up to 3275 m in altitude conducted using a car-mounted high-sensitivity neutron detector. The second was a previous measured result focusing on the changes in neutron spectra near air/ground and air/water interfaces. The attenuation length of cosmic-ray neutrons in the lower atmosphere was estimated to be 163 g cm(-2) in Taiwan. Cosmic-ray neutron spectra vary with altitude and especially near interfaces. The determined spectra near the air/ground and air/water interfaces agree well with measurements for neutrons below 10 MeV. However, the high-energy portion of spectra was observed to be much higher than our previous estimation. Because high-energy neutrons contribute substantially to a dose evaluation, revising the annual sea-level effective dose from cosmic-ray neutrons at ground level in Taiwan to 35 ?Sv, which corresponds to a neutron flux of 5.30 × 10(-3) n cm(-2) s(-1), was suggested. PMID:24573968

  11. Cosmic-ray acceleration in supernova remnants

    NASA Astrophysics Data System (ADS)

    Helder, E. A.

    2010-09-01

    Supernovae are among the most energetic events in the Universe. During the event, they expel their material with enormous speeds into the surroundings. In addition, supernovae are thought to transfer a sizable fraction of their energy into just a few particles: cosmic rays. These cosmic rays acquire so much energy that they escape the supernova material with almost the speed of light. Some of these cosmic rays arrive on Earth, where in an unfortunate case, they can do damage to the electronics onboard satellites. This thesis describes several studies on the observational imprints of cosmic-ray acceleration in supernova remnants. We use optical and X-ray data to study how much energy is lost from the remnants to cosmic rays and how this energy is transferred to the particles.

  12. High energy neutrino absorption and its effects on stars in close X-ray binaries

    NASA Technical Reports Server (NTRS)

    Gaisser, T. K.; Stecker, F. W.

    1986-01-01

    The physics and astrophysics of high energy neutrino production and interactions in close X-ray binary systems are studied. These studies were stimulated by recent observations of ultrahigh energy gamma-rays and possibly other ultrahigh energy particles coming from the directions of Cygnus X-3 and other binary systems and possessing the periodicity characteristics of these systems. Systems in which a compact object, such as a neutron star, is a strong source of high energy particles which, in turn, produce photons, neutronos and other secondary particles by interactions in the atmosphere of the companion star were considered. The highest energy neutrinos are absorbed deep in the companion and the associated energy deposition may be large enough to effect its structure or lead to its ultimate disruption. This neutrino heating was evaluated, starting with a detailed numerical calculation of the hadronic cascade induced in the atmosphere of the companion star. For some theoretical models, the resulting energy deposition from neutrino absorption may be so great as to disrupt the companion star over an astronomically small timescale of the order of 10,000 years. Even if the energy deposition is smaller, it may still be high enough to alter the system substantially, perhaps leading to quenching of high energy signals from the source. Given the cosmic ray luminosities required to produce the observed gamma rays from cygnus X-3 and LMX X-4, such a situation may occur in these sources.

  13. Extragalactic Absorption of High Energy Gamma-Rays

    E-print Network

    F. W. Stecker

    1999-04-29

    The pair-production absorption of high-energy gamma-rays by intergalactic low-energy photons is expected to produce a high-energy cutoff in the spectra of extragalactic sources which is a sensitive function of redshift. We first discuss the expected absorption coefficient as a function of energy and redshift derived by Stecker and De Jager by making use of a new empirically based calculation of the spectral energy distribution of the intergalactic infrared radiation field as given by Malkan and Stecker. We then discuss the fact that new data on the high energy gamma-ray source Mrk 501 appear to show the amount of intergalactic absorption predicted. The implications of this new HEGRA data, should they be confirmed, are significant for the astrophysics of this source, implying that (1) there is no significant intrinsic absorption inside the source, and (2) the physics of the emission produces a power-law spectrum to energies above 20 TeV. As a further test for intergalactic absorption, we give a predicted spectrum, with absorption included, for PKS 2155-304. This XBL lies at a redshift of 0.12, the highest redshift source yet observed at an energy above 0.3 TeV. We also discuss the determination of the gamma-ray opacity of the universe at higher redshifts (out to $z=3$), following the treatment of Salamon and Stecker.

  14. High-energy gamma-ray and neutrino backgrounds from clusters of galaxies and radio constraints

    NASA Astrophysics Data System (ADS)

    Zandanel, Fabio; Tamborra, Irene; Gabici, Stefano; Ando, Shin'ichiro

    2015-06-01

    Cosmic-ray protons accumulate for cosmological times in clusters of galaxies because their typical radiative and diffusive escape times are longer than the Hubble time. Their hadronic interactions with protons of the intra-cluster medium generate secondary electrons, gamma rays, and neutrinos. In light of the high-energy neutrino events recently discovered by the IceCube neutrino observatory, for which galaxy clusters have been suggested as possible sources, and the forthcoming results from the Fermi gamma-ray survey, we here estimate the contribution from galaxy clusters to the diffuse gamma-ray and neutrino backgrounds. We modelled the cluster population by means of their mass function, using a phenomenological luminosity-mass relation applied to all clusters, as well as a detailed semi-analytical model. In the latter model, we divide clusters into cool-core/non-cool-core, and loud/quiet subsamples, as suggested by observations, and model the cosmic-ray proton population according to state-of-the-art hydrodynamic numerical simulations. Additionally, we consider observationally-motivated values for the cluster magnetic field. This is a crucial parameter since the observed radio counts of clusters need to be respected owing to synchrotron emission by secondary electrons. For a choice of parameters respecting current constraints from radio to gamma rays, and assuming a proton spectral index of -2, we find that hadronic interactions in clusters contribute less than 10% to the IceCube flux and much less to the total extragalactic gamma-ray background observed by Fermi. They account for less than 1% for spectral indices ?-2. The high-energy neutrino flux observed by IceCube can be reproduced without violating radio constraints only if a very hard (and speculative) spectral index >-2 is adopted. However, this scenario is in tension with the high-energy IceCube data, which seems to suggest a spectral energy distribution of the neutrino flux that decreases with the particle energy. We prove that IceCube should be able to test our most optimistic scenarios for spectral indices ?-2.2 by stacking a few nearby massive galaxy clusters. In the case of proton-photon interactions in clusters, we find that very likely protons do not reach sufficiently high energies to produce neutrinos in these environments. We argue that our results are optimistic because of our assumptions and that clusters of galaxies cannot make any relevant contribution to the extragalactic gamma-ray and neutrino backgrounds in any realistic scenario. Finally, we find that the cluster contribution to the angular fluctuations in the gamma-ray background is subdominant, less than 10% on sub-degree scales.

  15. Research in cosmic and gamma ray astrophysics

    NASA Technical Reports Server (NTRS)

    Stone, E. C.; Davis, L., Jr.; Mewaldt, R. A.; Prince, T. A.

    1989-01-01

    Research activities in cosmic rays, gamma rays, and astrophysical plasmas are covered. The activities are divided into sections and described, followed by a bibliography. The astrophysical aspects of cosmic rays, gamma rays, and of the radiation and electromagnetic field environment of the Earth and other planets are investigated. These investigations are performed by means of energetic particle and photon detector systems flown on spacecraft and balloons.

  16. The Discovery and Nature of Cosmic Rays

    NSDL National Science Digital Library

    2012-08-03

    In this lesson, students will learn how cosmic rays were discovered and what they are - including their size and speed. Includes background information for the teacher, questions, activities and information about student preconceptions. This is lesson 1 of 4 from "The Cosmic Ray Telescope for the Effects of Radiation (CRaTER)."

  17. Tracks of Cosmic Rays in Plastics

    Microsoft Academic Search

    R. L. Fleischer; P. B. Price; R. M. Walker; R. C. Filz; K. Fukui; M. W. Friedlander; E. Holeman; R. S. Rajan; A. S. Tamhane

    1967-01-01

    Cosmic ray nuclei have been observed with the use of plastic track-detecting solids in satellites and high-altitude balloon flights. Nuclear emulsions in the stacks of plastic sheets allowed the positive identification of cosmic ray nuclei as light as nitrogen. The most striking new information was the failure to observe relativistic iron nuclei, a result which has led to an advance

  18. Cosmic Rays on the Pacific Ocean

    Microsoft Academic Search

    A. H. Compton; R. N. Turner

    1937-01-01

    Records of cosmic-ray intensity obtained on the R. M. S. Aorangi during 12 voyages between Vancouver, Canada and Sydney, Australia, from March 17, 1936, to January 18, 1937, using a Carnegie model C cosmic-ray meter, are described and discussed. Typical records exhibiting the latitude effect are shown. A summary of the data taken at sea is given in the form

  19. Diagnostic Spectrometers for High Energy Density X-Ray Sources

    SciTech Connect

    Hudson, L. T.; Henins, A. [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Seely, J. F.; Holland, G. E. [Naval Research Laboratory, Space Science Division, Washington DC 20375 (United States)

    2007-08-02

    A new generation of advanced laser, accelerator, and plasma confinement devices are emerging that are producing extreme states of light and matter that are unprecedented for laboratory study. Examples of such sources that will produce laboratory x-ray emissions with unprecedented characteristics include megajoule-class and ultrafast, ultraintense petawatt laser-produced plasmas; tabletop high-harmonic-generation x-ray sources; high-brightness zeta-pinch and magnetically confined plasma sources; and coherent x-ray free electron lasers and compact inverse-Compton x-ray sources. Characterizing the spectra, time structure, and intensity of x rays emitted by these and other novel sources is critical to assessing system performance and progress as well as pursuing the new and unpredictable physical interactions of interest to basic and applied high-energy-density (HED) science. As these technologies mature, increased emphasis will need to be placed on advanced diagnostic instrumentation and metrology, standard reference data, absolute calibrations and traceability of results.We are actively designing, fabricating, and fielding wavelength-calibrated x-ray spectrometers that have been employed to register spectra from a variety of exotic x-ray sources (electron beam ion trap, electron cyclotron resonance ion source, terawatt pulsed-power-driven accelerator, laser-produced plasmas). These instruments employ a variety of curved-crystal optics, detector technologies, and data acquisition strategies. In anticipation of the trends mentioned above, this paper will focus primarily on optical designs that can accommodate the high background signals produced in HED experiments while also registering their high-energy spectral emissions. In particular, we review the results of recent laboratory testing that explores off-Rowland circle imaging in an effort to reclaim the instrumental resolving power that is increasingly elusive at higher energies when using wavelength-dispersive techniques. These efforts inform the optimization of diagnostic designs that will permit acquisition of high-resolution, hard x-ray spectra in the HED environment.

  20. Cosmic ray composition investigations using ICE/ISEE-3

    NASA Technical Reports Server (NTRS)

    Wiedenbeck, Mark E.

    1992-01-01

    The analysis of data from the high energy cosmic experiment on ISEE-3 and associated modeling and interpretation activities are discussed. The ISEE-3 payload included two instruments capable of measuring the composition of heavy cosmic rays. The designs of these two instruments incorporated innovations which made it possible, for the first time, to measure isotopic as well as the chemical composition for a wide range of elements. As the result of the demonstrations by these two instruments of the capability to resolve individual cosmic ray isotopes, a new generation of detectors was developed using very similar designs, but having improved reliability and increased sensitive area. The composition measurements which were obtained from the ISEE-3 experiment are summarized.

  1. The AMS tracking detector for cosmic-ray physics in space

    Microsoft Academic Search

    Maurice Bourquin

    2005-01-01

    AMS-02 is a general-purpose spectrometer designed to measure cosmic rays and gamma rays in near-Earth orbit. The main scientific motivations are the search for cosmic anti-matter, the search for dark matter, precision measurements on the relative abundance of different nuclei and isotopes, as well as the measurement of very high-energy gamma rays. Constructed by a large international collaboration of institutes

  2. Large-area transition radiation detectors for cosmic-ray observations in space

    Microsoft Academic Search

    Dietrich Mueller; Edward Diehl; Florian Gahbauer; Peter Meyer; Simon Swordy

    1996-01-01

    The characteristic dependence of x-ray transition radiation on the Lorentz factor of the parent particle can be utilized in cosmic-ray observations on balloons or in space in order to discriminate between relativistic electrons and hadrons, or to determine the energy spectra of heavy cosmic-ray nuclei at very high energies. To obtain statistically meaningful results, exposure factors of the instruments of

  3. Cosmic-Ray Modulation Equations

    NASA Astrophysics Data System (ADS)

    Moraal, H.

    2013-06-01

    The temporal variation of the cosmic-ray intensity in the heliosphere is called cosmic-ray modulation. The main periodicity is the response to the 11-year solar activity cycle. Other variations include a 27-day solar rotation variation, a diurnal variation, and irregular variations such as Forbush decreases. General awareness of the importance of this cosmic-ray modulation has greatly increased in the last two decades, mainly in communities studying cosmogenic nuclides, upper atmospheric physics and climate, helio-climatology, and space weather, where corrections need to be made for these modulation effects. Parameterized descriptions of the modulation are even used in archeology and in planning the flight paths of commercial passenger jets. The qualitative, physical part of the modulation is generally well-understood in these communities. The mathematical formalism that is most often used to quantify it is the so-called Force-Field approach, but the origins of this approach are somewhat obscure and it is not always used correct. This is mainly because the theory was developed over more than 40 years, and all its aspects are not collated in a single document. This paper contains a formal mathematical description intended for these wider communities. It consists of four parts: (1) a description of the relations between four indicators of "energy", namely energy, speed, momentum and rigidity, (2) the various ways of how to count particles, (3) the description of particle motion with transport equations, and (4) the solution of such equations, and what these solutions mean. Part (4) was previously described in Caballero-Lopez and Moraal (J. Geophys. Res, 109: A05105, doi: 10.1029/2003JA010358, 2004). Therefore, the details are not all repeated here. The style of this paper is not to be rigorous. It rather tries to capture the relevant tools to do modulation studies, to show how seemingly unrelated results are, in fact, related to one another, and to point out the historical context of some of the results. The paper adds no new knowledge. The summary contains advice on how to use the theory most effectively.

  4. High Energy Gamma-Ray Emission From Blazars: EGRET Observations

    E-print Network

    R. Mukherjee

    1999-01-17

    We will present a summary of the observations of blazars by the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO). EGRET has detected high energy gamma-ray emission at energies greater than 100 MeV from more that 50 blazars. These sources show inferred isotropic luminosities as large as $3\\times 10^{49}$ ergs s$^{-1}$. One of the most remarkable characteristics of the EGRET observations is that the gamma-ray luminosity often dominates the bolometric power of the blazar. A few of the blazars are seen to exhibit variability on very short time-scales of one day or less. The combination of high luminosities and time variations seen in the gamma-ray data indicate that gamma-rays are an important component of the relativistic jet thought to characterize blazars. Currently most models for blazars involve a beaming scenario. In leptonic models, where electrons are the primary accelerated particles, gamma-ray emission is believed to be due to inverse Compton scattering of low energy photons, although opinions differ as to the source of the soft photons. Hardronic models involve secondary production or photomeson production followed by pair cascades, and predict associated neutrino production.

  5. High-Energy Diffraction-Enhanced X-ray Imaging

    SciTech Connect

    Yoneyama, Akio; Ueda, Kazuhiro [Advanced Research Laboratory, Hitachi Ltd., 2520, Akanuma, Hatoyama, Saitama, 350-0395 (Japan); Takeda, Tohoru [Allied Health Sciences, Kitasato University, Sagamihara, Kanagawa 228-8555 (Japan); Yamazaki, Takanori [Research and Development Laboratory, Hitachi Cable, Ltd., 5-1-1, Hidakacho, Hitachi, Ibaraki, 319-1414 (Japan); Hyodo, Kazuyuki [Institute of Materials Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki, 305-0801 (Japan)

    2010-06-23

    In order to apply the diffraction-enhanced X-ray imaging (DEI) method for much wider variety of samples, we have developed the high-energy DEI system. The energy of X-ray was increased up to 70 keV to achieve high permeability for heavy elements. The diffraction of Si(440) was used to keep large field of view. Demonstrative observation of an electrical cable was performed using the X-ray emitted from the vertical wiggler. The obtained images visualized not only the core and ground wire made of copper but also the isolator and outer jacket made of polymer clearly. The comparison of images obtained by the DEI and the absorption-contrast imaging showed that the sensitivity of DEI is about 10 times higher than that of the absorption method for light elements, and 3 times for heavy elements.

  6. Models for Galactic cosmic-ray propagation

    E-print Network

    A. W. Strong; I. V. Moskalenko

    2001-01-04

    A new numerical model of particle propagation in the Galaxy has been developed, which allows the study of cosmic-ray and gamma-ray production and propagation in 2D or 3D, including a full reaction network. This is a further development of the code which has been used for studies of cosmic ray reacceleration, Galactic halo size, antiprotons and positrons in cosmic rays, the interpretation of diffuse continuum gamma rays, and dark matter. In this paper we illustrate recent results focussing on B/C, sub-Fe/Fe, ACE radioactive isotope data, source abundances and antiprotons. From the radioactive nuclei we derive a range of 3-7 kpc for the height of the cosmic-ray halo.

  7. On the spectrum of Ultrahigh Energy Cosmic Rays and the Gamma Ray Burst Origin Hypothesis

    E-print Network

    S. T. Scully; F. W. Stecker

    2001-03-21

    It has been suggested that cosmological gamma-ray bursts (GRBs) can produce the observed flux of cosmic rays at the highest energies. However, recent studies of GRBs indicate that their redshift distribution likely follows that of the average star formation rate and that GRBs were more numerous at high redshifts. As a consequence, we show that photomeson production energy losses suffered by ultrahigh energy cosmic rays coming from GRBs would produce too sharp a spectral high energy cutoff to be consistent with the air shower data. Furthermore, we show that cosmological GRBs fail to supply the energy input required to account for the cosmic ray flux above 10 EeV by a factor of 100-1000.

  8. Pointlike gamma ray sources as signatures of distant accelerators of ultrahigh energy cosmic rays.

    PubMed

    Gabici, Stefano; Aharonian, Felix A

    2005-12-16

    We discuss the possibility of observing distant accelerators of ultrahigh energy cosmic rays in synchrotron gamma rays. Protons propagating away from their acceleration sites produce extremely energetic electrons during photopion interactions with cosmic microwave background photons. If the accelerator is embedded in a magnetized region, these electrons will emit high energy synchrotron radiation. The resulting synchrotron source is expected to be pointlike, steady, and detectable in the GeV-TeV energy range if the magnetic field is at the nanoGauss level. PMID:16384444

  9. Maximum Particle Energies by Fermi Acceleration and the Origin of Cosmic Rays above the Knee

    E-print Network

    Charles D. Dermer

    2001-07-11

    We derive the maximum accelerated particle energy from first-order and second-order Fermi acceleration at nonrelativistic and relativistic shocks for explosions taking place in a uniform surrounding medium. Second-order stochastic processes in relativistic flows are shown to be capable of accelerating cosmic rays to ultra-high energies. Cosmic rays above the knee of the cosmic ray spectrum can be accelerated by the second-order Fermi mechanism in relativistic flows, such as those occuring in gamma-ray bursts and unusual supernovae like SN 1998bw.

  10. Multiwavelength observations of unidentified high energy gamma ray sources

    NASA Technical Reports Server (NTRS)

    Halpern, Jules P.

    1993-01-01

    As was the case for COS B, the majority of high-energy (greater than 100 MeV) gamma-ray sources detected by the EGRET instrument on GRO are not immediately identifiable with cataloged objects at other wavelengths. These persistent gamma-ray sources are, next to the gamma-ray bursts, the least understood objects in the universe. Even a rudimentary understanding of their nature awaits identifications and follow-up work at other wavelengths to tell us what they are. The as yet unidentified sources are potentially the most interesting, since they may represent unrecognized new classes of astronomical objects, such as radio-quiet pulsars or new types of active galactic nuclei (AGN's). This two-year investigation is intended to support the analysis, correlation, and theoretical interpretation of data that we are obtaining at x ray, optical, and radio wavelengths in order to render the gamma-ray data interpretable. According to plan, in the first year concentration was on the identification and study of Geminga. The second year will be devoted to studies of similar unidentified gamma-ray sources which will become available in the first EGRET catalogs. The results obtained so far are presented in the two papers which are reproduced in the Appendix. In these papers, we discuss the pulse profiles of Geminga, the geometry and efficiency of the magnetospheric accelerator, the distance to Geminga, the implications for theories of polar cap heating, the effect of the magnetic field on the surface emission and environment of the neutron star, and possible interpretations of a radio-quiet Geminga. The implications of the other gamma-ray pulsars which were discovered to have high gamma-ray efficiency are also discussed, and the remaining unidentified COS B sources are attributed to a population of efficient gamma-ray sources, some of which may be radio quiet.

  11. Discovery of the candidate pulsar wind nebula HESS J1718-385 in very-high-energy gamma-rays

    E-print Network

    H. E. S. S Collaboration; :; S. Carrigan; Y. A. Gallant; J. A. Hinton; Nu. Komin; K. Kosack; C. Stegmann

    2007-09-27

    Motivated by recent detections of pulsar wind nebulae in very-high-energy (VHE) gamma rays, a systematic search for VHE gamma-ray sources associated with energetic pulsars was performed, using data obtained with the H.E.S.S. (High Energy Stereoscopic System) instrument. The search for VHE gamma-ray sources near the pulsar PSR J1718-3825 revealed the new VHE gamma-ray source HESS J1718-385. We report on the results from the HESS data analysis of this source and on possible associations with the pulsar and at other wavelengths. We investigate the energy spectrum of HESS J1718-385 that shows a clear peak. This is only the second time a VHE gamma-ray spectral maximum from a cosmic source was observed, the first being the Vela X pulsar wind nebula.

  12. Cosmic Rays Variations and Human Physiological State

    NASA Astrophysics Data System (ADS)

    Dimitrova, S.

    2009-12-01

    It was obtained in our previous investigations that geomagnetic activity as an indirect indicator of solar activity correlates with some human physiological and psycho-physiological parameters. A lot of studies indicate that other parameters of space weather like cosmic rays Forbush decreases affect myocardial infarction, brain stroke, car accidents, etc. The purpose of that work was to study the effect of cosmic rays variations on human physiological status. It was established that the decrease in cosmic rays intensity was related to an increase in systolic and diastolic blood pressure and reported subjective psycho-physiological complaints in healthy volunteers.

  13. The soft ?-ray pulsar population: a high-energy overview

    NASA Astrophysics Data System (ADS)

    Kuiper, L.; Hermsen, W.

    2015-06-01

    At high-energy ?-rays (>100 MeV), the Large Area Telescope (LAT) on the Fermi satellite already detected more than 145 rotation-powered pulsars (RPPs), while the number of pulsars seen at soft ?-rays (20 keV-30 MeV) remained small. We present a catalogue of 18 non-recycled RPPs from which presently non-thermal pulsed emission has been securely detected at soft ?-rays above 20 keV, and characterize their pulse profiles and energy spectra. For 14 of them, we report new results, (re)analysing mainly data from RXTE, INTEGRAL, XMM-Newton and Chandra. The soft ?-pulsars are all fast rotators and on average ˜9.3 times younger and ˜43 times more energetic than the Fermi LAT sample. The majority (11 members) exhibits broad, structured single pulse profiles, and only six have double (or even multiple, Vela) pulses. 15 soft ?-ray pulsar show hard power-law spectra in the hard X-ray band and reach maximum luminosities typically in the MeV range. For only 7 of the 18 soft ?-ray pulsars, pulsed emission has also been detected by the LAT, but 12 have a pulsar wind nebula (PWN) detected at TeV energies. For six pulsars with PWNe, we present also the spectra of the total emissions at hard X-rays, and for IGR J18490-0000, associated with HESS J1849-000 and PSR J1849-0001, we used our Chandra data to resolve and characterize the contributions from the point source and PWN. Finally, we also discuss a sample of 15 pulsars which are candidates for future detection of pulsed soft ?-rays, given their characteristics at other wavelengths.

  14. AGILE: The Next High-Energy Gamma-Ray Mission

    NASA Astrophysics Data System (ADS)

    Tavani, M.; Argan, A.; Auricchio, N.; Barbiellini, G.; Caraveo, P.; Celesti, E.; Chen, A.; Cocco, V.; Conti, M.; Costa, E.; Di Cocco, G.; Fedel, G.; Feroci, M.; Fiorini, M.; Froysland, T.; Ghirlanda, G.; Galli, M.; Gianotti, F.; Giuliani, A.; Labanti, C.; Lapshov, I.; Lipari, P.; Longo, F.; Mauri, A.; Mereghetti, S.; Morelli, E.; Morselli, A.; Pacciani, L.; Pellizzoni, A.; Perotti, F.; Picozza, P.; Pittori, C.; Pontoni, C.; Porrovecchio, J.; Preger, B.; Prest, M.; Rapisarda, M.; Rossi, E.; Rubini, A.; Soffitta, P.; Soldi, S.; Traci, A.; Trifoglio, M.; Vallazza, E.; Vercellone, S.; Zanello, D.

    2003-03-01

    In this presentation we review the current status of the AGILE Mission. AGILE, a Small Scientific Mission of the Italian Space Agency (ASI) will study celestial sources emitting in the gamma-ray energy band 30 MeV - 50 GeV, combined - for the first time in high-energy gamma-ray astronomy - with monitoring capabilities in the hard X-ray band 10 - 40 keV. Because of its large field of view ( ˜ 3 sr), the small deadtime (lower than 200 microsec), and broad-band detection capabilities, AGILE is ideal to perform a large number of tasks: monitoring active galactic nuclei (AGNs),detecting gamma-ray bursts (GRBs) with high efficiency, mapping the diffuse Galactic and extragalactic emission, studying pulsed gamma-ray emission from radiopulsars, and monitoring the many unidentified sources contributing to their unveiling. The AGILE Mission is planned to operate during the years 2004-2006 and its Science Program emphasizes the quick reaction to transients and rapid communication of science data for fast follow-up multiwavelength observations.

  15. High-energy gamma-ray absorption in relativistic magnetospheres

    NASA Technical Reports Server (NTRS)

    Riffert, H.; Meszaros, P.; Bagoly, Z.

    1989-01-01

    Calculations are made of the propagation of gamma-rays around neutron stars with a dipole magnetic field, including the effects of general relativity and the absorption by the one-photon magnetic pair production process, as a model for the high-energy transport in gamma-ray burst sources and pulsars. The paper discusses the escaping photon beam characteristics as seen by distant observers at different angles with respect to the magnetic axis, for radiation arising from the polar caps of neutron stars of varying degrees of compactness and surface field strengths. The observed beaming depends strongly on the surface field only up to B of about 0.05 times the critical field value, being essentially constant above the value 0.1. The gravitational light bending contributes significantly to broaden the beam profiles especially at low energies above threshold, being sensitive to the stellar radius to mass ratio.

  16. High-energy gamma-ray absorption in relativistic magnetospheres

    SciTech Connect

    Riffert, H.; Meszaros, P.; Bagoly, Z.

    1989-05-01

    Calculations are made of the propagation of gamma-rays around neutron stars with a dipole magnetic field, including the effects of general relativity and the absorption by the one-photon magnetic pair production process, as a model for the high-energy transport in gamma-ray burst sources and pulsars. The paper discusses the escaping photon beam characteristics as seen by distant observers at different angles with respect to the magnetic axis, for radiation arising from the polar caps of neutron stars of varying degrees of compactness and surface field strengths. The observed beaming depends strongly on the surface field only up to B of about 0.05 times the critical field value, being essentially constant above the value 0.1. The gravitational light bending contributes significantly to broaden the beam profiles especially at low energies above threshold, being sensitive to the stellar radius to mass ratio. 18 refs.

  17. High energy transmission annular beam X-ray diffraction.

    PubMed

    Dicken, Anthony; Shevchuk, Alex; Rogers, Keith; Godber, Simon; Evans, Paul

    2015-03-01

    We demonstrate material phase retrieval by linearly translating extended polycrystalline samples along the symmetry axis of an annular beam of high-energy X-rays. A series of pseudo-monochromatic diffraction images are recorded from the dark region encompassed by the beam. We measure Bragg maxima from different annular gauge volumes in the form of bright spots in the X-ray diffraction intensity. We present the experiment data from three materials with different crystallographic structural properties i.e. near ideal, large grain size and preferred orientation. This technique shows great promise for analytical inspection tasks requiring highly penetrating radiation such as security screening, medicine and non-destructive testing. PMID:25836851

  18. Very-High-Energy Observations of X-Ray Binaries

    SciTech Connect

    Ribo, Marc [Departament d'Astronomia i Meteorologia, Universitat de Barcelona, Marti i Franques 1, E-08028 Barcelona (Spain)

    2008-05-23

    The new generation of imaging atmospheric Cherenkov telescopes (HESS, MAGIC, VERITAS) has allowed us to conduct sensitive observations in the TeV regime. Several X-ray binaries have been detected, among them PSR B1259-63, LS 5039, LS I +61 303 and, very recently, Cygnus X-1. All of them contain high-mass donors. While in the case of PSR B1259-63 the compact object is a confirmed young non-accreting pulsar, and in the case of Cygnus X-1 it is a dynamically confirmed stellar-mass black hole and microquasar jet source, the situation is not yet clear in the cases of LS 5039 and LS I +61 303. I summarize here the current status of Very-High-Energy observations of X-ray binaries and discuss possible scenarios that have been put forward to explain the TeV emission of these systems.

  19. Consistency of cosmic-ray source abudances with explosive nucleosynthesis

    NASA Technical Reports Server (NTRS)

    Kozlovsky, B.; Ramaty, R.

    1973-01-01

    A model was examined in which the cosmic ray abundances of elements from C to Fe are consistent with explosive nucleosynthesis. The observed abundance of cosmic rays near the earth, cosmic ray source abundance, and solar system abundance are discussed along with the ratios of cosmic ray sources to the solar system abundances.

  20. Superdiffusion of cosmic rays: Implications for cosmic ray acceleration

    SciTech Connect

    Lazarian, A. [Department of Astronomy, University of Wisconsin, 475 North Charter Street, Madison, WI 53706 (United States); Yan, Huirong [KIAA, Peking University, 5 Yi He Yuan Rd, Beijing, 100871 (China)

    2014-03-20

    Diffusion of cosmic rays (CRs) is the key process for understanding their propagation and acceleration. We employ the description of spatial separation of magnetic field lines in magnetohydrodynamic turbulence in Lazarian and Vishniac to quantify the divergence of the magnetic field on scales less than the injection scale of turbulence and show that this divergence induces superdiffusion of CR in the direction perpendicular to the mean magnetic field. The perpendicular displacement squared increases, not as the distance x along the magnetic field, which is the case for a regular diffusion, but as the x {sup 3} for freely streaming CRs. The dependence changes to x {sup 3/2} for the CRs propagating diffusively along the magnetic field. In the latter case, we show that it is important to distinguish the perpendicular displacement with respect to the mean field and to the local magnetic field. We consider how superdiffusion changes the acceleration of CRs in shocks and show how it decreases efficiency of the CRs acceleration in perpendicular shocks. We also demonstrate that in the case when the small-scale magnetic field is generated in the pre-shock region, an efficient acceleration can take place for the CRs streaming without collisions along the magnetic loops.

  1. Cosmic Ray Nuclei (CRN) detector investigation

    Microsoft Academic Search

    Peter Meyer; Dietrich Muller; Jacques Lheureux; Simon Swordy

    1991-01-01

    The Cosmic Ray Nuclei (CRN) detector was designed to measure elemental composition and energy spectra of cosmic radiation nuclei ranging from lithium to iron. CRN was flown as part of Spacelab 2 in 1985, and consisted of three basic components: a gas Cerenkov counter, a transition radiation detector, and plastic scintillators. The results of the experiment indicate that the relative

  2. The origin of the spectral intensities of cosmic-ray positrons

    SciTech Connect

    Cowsik, R.; Burch, B.; Madziwa-Nussinov, T., E-mail: cowsik@physics.wustl.edu [Campus Box 1105, 1 Brookings Drive, St. Louis, MO 63130, USA. (United States)

    2014-05-10

    We present a straightforward model of cosmic-ray propagation in the Galaxy that can account for the observed cosmic-ray positrons entirely as secondary products of cosmic-ray interactions with the interstellar medium. In addition to accounting for the observed energy dependence of the ratio of positrons to total electrons, this model can accommodate both the observed energy dependence of secondary to primary nuclei, like boron/carbon, and the observed bounds on the anisotropy of cosmic rays. This model also predicts the energy dependence of the positron fraction at energies higher than those measured to date, with the ratio rising to ?0.7 at very high energies. The model presented in this paper arises as a natural extension of the widely used current models and allows one to include the spatial and temporal discreteness of the sources of cosmic rays.

  3. Clues to the origin of cosmic rays derived from their source composition and energy spectra

    SciTech Connect

    Koch-Miramond, L.; Meyer, J.P.

    1984-01-01

    Cosmic ray composition and energy spectra at source have been recently obtained with good precision. The bulk of the observations suggests that cosmic rays originate in unevolved star surface material. Most cosmic rays should be stellar energetic particles first accelerated by flares out of the coronae of F to M stars, that were later reaccelerated to high energy by strong interstellar shockwaves. The limitations of this two-step scenario and of the other plausible stellar and interstellar models are pointed out. The Ne-22 and carbon excesses at cosmic ray source are accounted for if a minor component (2 percent) of cosmic rays are made of He-burning material, plausibly originating in Wolf-Rayet stars. The possible oxygen and Mg-25, Mg-26 excesses could be interpreted in the same context, but not the Si-29, Si-30 excess. 91 references.

  4. Building a Cloud Chamber (Cosmic Ray Detector)

    NSDL National Science Digital Library

    In this activity, students learn about cosmic rays firsthand by building a cloud chamber to detect them. The comprehensive activity includes step-by-step directions for constructing and operating a cloud chamber and ideas for additional experiments.

  5. Ultra-High Energy Cosmic Radiation: Current Issues and Future Prospects

    SciTech Connect

    Sigl, Guenter [Institut fuer theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, D-22761 Hamburg (Germany)

    2010-11-24

    We briefly review the current experimental and theoretical status of cosmic radiation above {approx}10{sup 17} eV, including secondary neutrinos and gamma-rays. We focus on questions related to chemical composition and sky distributions of these particles as well as on the location and nature of their sources.

  6. Apollo 17 lunar surface cosmic ray detector

    NASA Technical Reports Server (NTRS)

    Walker, R. M.

    1974-01-01

    The objectives and selected data are presented for the Apollo 17 Lunar Surface Cosmic Ray Experiment (LSCRE) for the purpose of introducing an analysis of three of the separate detectors contained within in LSCRE package. The mica detector for measuring heavy solar wind, and the lexan stack and glass detectors for measuring energetic particles in space are discussed in terms of their deployment, exposure time, calibration, and data yield. Relevant articles on solar particles, interplanetary ions, and cosmic ray nuclei are also included.

  7. SCATTERING OF HIGHER ENERGY COSMIC RAYS

    E-print Network

    Melrose, Don

    s discussed by Wentzel (1969a), Kulsrud and Pearce (1969), Tademaru (1969), S k i l l i n g (1970) and Melrose and Wentzel (1970). As applied t o cosmic rays t h i s theory f a i l s i n t h a t higher energy cosmic rays and Wentzel (1970). Terms of the order vA/c are neglected in (1). The most important of these neglected terms

  8. CALET Mission for the Observation of Cosmic Rays on the International Space Station

    Microsoft Academic Search

    Tadahisa Tamura; Shoji Torii; Katsuaki Kasahara; Osamu Okudaira; Nobuyuki Hasebe; Makoto Hareyama; Hiromitsu Miyajima; Takashi Miyaji; Naoyuki Yamashita; Shiro Ueno; Yoshitaka Saito; Masahiro Takayanagi; Hiroshi Tomita; Jun Nishimura; Hideyuki Fuke; Takamasa Yamagami; Shoji Okuno; Nobuto Tateyama; Kinya Hibino; Atsushi Shiomi; Masato Takita; Toshinori Yuda; Yuki Shimizu; Fumio Kakimoto; Yoshiki Tsunesada; Toshio Terasawa; Tadashi Kobayashi; Atsumasa Yoshida; Kazutaka Yamaoka; Yusaku Katayose; Makio Shibata; Kenji Yoshida; Masaichi Ichimura; Shuichi Kuramata; Yukio Uchihori; Hisashi Kitamura; Hiroyuki Murakami; Yoshiko Komori; Kohei Mizutani; Kazuki Munakata; Robert E. Streitmatter; John W. Mitchell; Louis M. Barbier; Alexander A. Moissev; John F. Krizmanic; Gary L. Case; Michael L. Cherry; T. G. Guzik; Joachim B. Isbert; John P. Wefel; Walter R. Binns; Martin H. Israel; H. S. Krawzczynski; Jonathan F. Ormes; Pier S. Marrocchesi; Paolo Maestro; Maria G. Bagliesi; Vincenzo Millucci; Mario Meucci; Gabriele Bigongiari; Riccardo Zei; Meyoung Kim; Oscar Adriani; Paolo Papini; Lorenzo Bonechi; Vannuccini Elena; Fabio Morsani; Franco Ligabue; Jin Chang; Weiqun Gan; Ji Yang; Yuqian Ma; Huanyu Wang; Guoming Chen

    2009-01-01

    We have proposed CALET (CALorimetric Electron Telescope) mission to make observations of high energy cosmic rays, electrons, gamma-rays, and nuclei, on the International Space Station (ISS). CALET mission has been approved as one of candidates for the next mission utilizing the Japanese Experiment Module (JEM). The detector of CALET consists of an imaging calorimeter (IMC) and a total absorption calorimeter

  9. The 28th International Cosmic Ray Conference 1 X-ray and Gamma-ray Measurements

    E-print Network

    Enomoto, Ryoji

    The 28th International Cosmic Ray Conference 1 X-ray and Gamma-ray Measurements Masaki Mori and gamma-ray measurements, of the 28th International Cosmic Ray Conference. 1. Introduction Thick atmosphere of the earth forces direct observations of X-rays and gamma-rays on satellites in space

  10. Multi-spectra Cosmic Ray Flux Measurement

    NASA Astrophysics Data System (ADS)

    He, Xiaochun; Dayananda, Mathes

    2010-02-01

    The Earth's upper atmosphere is constantly bombarded by rain of charged particles known as primary cosmic rays. These primary cosmic rays will collide with the atmospheric molecules and create extensive secondary particles which shower downward to the surface of the Earth. In recent years, a few studies have been done regarding to the applications of the cosmic ray measurements and the correlations between the Earth's climate conditions and the cosmic ray fluxes [1,2,3]. Most of the particles, which reach to the surface of the Earth, are muons together with a small percentage of electrons, gammas, neutrons, etc. At Georgia State University, multiple cosmic ray particle detectors have been constructed to measure the fluxes and energy distributions of the secondary cosmic ray particles. In this presentation, we will briefly describe these prototype detectors and show the preliminary test results. Reference: [1] K.Borozdin, G.Hogan, C.Morris, W.Priedhorsky, A.Saunders, L.Shultz, M.Teasdale, Nature, Vol.422, 277 (2003). [2] L.V. Egorova, V. Ya Vovk, O.A. Troshichev, Journal of Atmospheric and Terrestrial Physics 62, 955-966 (2000). [3] Henrik Svensmark, Phy. Rev. Lett. 81, 5027 (1998). )

  11. Are Diffuse High Energy Neutrinos and Gamma-Rays from Starburst Galaxies Observable?

    E-print Network

    F. W. Stecker

    2006-08-18

    Loeb and Waxman have argued that high energy neutrinos from the decay of pions produced in interactions of cosmic rays with interstellar gas in starburst galaxies would be produced with a large enough flux to be observable. Their model is reexamined here and we obtain an upper limit to the diffuse neutrino flux from starburst galaxies. The upper limit obtained here is a factor of ~5 lower than the flux which they predict. Our predicted neutrino flux would be below the atmospheric neutrino foreground flux at energies below \\~300 TeV and therefore would be unobservable. PeV neutrinos from starburst galaxies are also unlikely to be detected. Compared with predicted fluxes from other extragalactic high energy neutrino sources, starburst neutrinos with ~PeV energies would have a flux considerably below that predicted for AGN models. We also estimate an upper limit for the diffuse GeV gamma-ray flux from starburst galaxies to be about two orders of magnitude below the observed gamma-ray background, much less than the background from blazars and more than an order of magnitude below that calculated by Thompson et al.

  12. COSMIC-RAY HELIUM HARDENING

    SciTech Connect

    Ohira, Yutaka; Ioka, Kunihito, E-mail: ohira@post.kek.jp [Theory Center, Institute of Particle and Nuclear Studies, KEK (High Energy Accelerator Research Organization), 1-1 Oho, Tsukuba 305-0801 (Japan)

    2011-03-01

    Recent observations by the CREAM and ATIC-2 experiments suggest that (1) the spectrum of cosmic-ray (CR) helium is harder than that of CR protons below the knee energy, 10{sup 15}eV, and (2) all CR spectra become hard at {approx}>10{sup 11}eV nucleon{sup -1}. We propose a new idea, that higher energy CRs are generated in a more helium-rich region, to explain the hardening without introducing different sources for CR helium. The helium-to-proton ratio at {approx}100 TeV exceeds the Big Bang abundance Y = 0.25 by several times, and the different spectrum is not reproduced within the diffusive shock acceleration theory. We argue that CRs are produced in a chemically enriched region, such as a superbubble, and the outward-decreasing abundance naturally leads to the hard spectrum of CR helium if CRs escape from the supernova remnant shock in an energy-dependent way. We provide a simple analytical spectrum that also fits well the hardening due to the decreasing Mach number in the hot superbubble with {approx}10{sup 6} K. Our model predicts hard and concave spectra for heavier CR elements.

  13. The Galactic Diffuse Gamma-ray Spectrum from Cosmic-ray Proton Interactions

    E-print Network

    Masaki Mori

    1996-11-28

    A new calculation of the Galactic diffuse gamma-ray spectrum from the decay of secondary particles produced by interactions of cosmic-ray protons with interstellar matter is presented. The calculation utilizes the modern Monte Carlo event generators, Hadrin, Fritiof and Pythia, which simulate high-energy proton-proton collisions and are widely used in studies of nuclear and particle physics, in addition to scaling calculation. This study is motivated by the result on the Galactic diffuse gamma-ray flux observed by the EGRET detector on the Compton Gamma-ray Observatory, which indicates an excess above about 1 GeV of the observed intensity compared with a model prediction. The prediction is based on cosmic-ray interactions with interstellar matter, in which secondary pion productions are treated by a simple model. With the improved interaction model used here, however, the diffuse gamma-ray flux agrees rather well with previous calculations within uncertainties, which mainly come from the unobservable demodulated cosmic-ray spectrum in interstellar space. As a possible solution to the excess flux, flatter spectra of cosmic-ray protons have been tested and we found that the power-law spectrum with an index of about $-(2.4\\sim2.5)$ gives a better fit to the EGRET data, though the spectrum is not explained completely.

  14. DAP Young Star: What PeV neutrinos teach us about Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Whitehorn, Nathan

    2014-03-01

    The origin of high-energy cosmic rays is one of the most persistent mysteries in physics. Neutrinos, as unambiguous tracers of hadronic acceleration, may offer a new and unique window into this problem and others in high-energy astrophysics. As neutral particles, they travel from their sources undeflected by magnetic fields, and as weakly interacting particles, they travel undisturbed out of dense environments. I will discuss recent results from the antarctic IceCube neutrino observatory, the first operating gigaton-scale neutrino detector, showing strong evidence for a population of extremely high energy neutrinos (100+ TeV) that cannot easily be explained by processes occurring in cosmic ray showers in the Earth's atmosphere, and the implications of neutrino astronomy for our understanding of cosmic rays.

  15. First Search for Point Sources of High-energy Cosmic Neutrinos with the ANTARES Neutrino Telescope

    NASA Astrophysics Data System (ADS)

    Adrián-Martínez, S.; Aguilar, J. A.; Samarai, I. Al; Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J.-J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigi, A.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M. C.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Cârloganu, C.; Carminati, G.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, Ph.; Chiarusi, T.; Circella, M.; Coniglione, R.; Costantini, H.; Coyle, P.; Curtil, C.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Enzenhöfer, A.; Ernenwein, J.-P.; Escoffier, S.; Fermani, P.; Ferri, M.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.-L.; Galatà, S.; Gay, P.; Giacomelli, G.; Giordano, V.; Gómez-González, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartman, J.; Heijboer, A. J.; Hello, Y.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hsu, C. C.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Lefèvre, D.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martínez-Mora, J. A.; Meli, A.; Montaruli, T.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.; Palioselitis, D.; P?v?la?, G. E.; Payet, K.; Payre, P.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Reed, C.; Richardt, C.; Richter, R.; Rivière, C.; Robert, A.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, G. V.; Salesa, F.; Samtleben, D. F. E.; Sapienza, P.; Schöck, F.; Schuller, J.-P.; Schüssler, F.; Seitz, T.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Sánchez-Losa, A.; Taiuti, M.; Tamburini, C.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wagner, S.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zúñiga, J.

    2011-12-01

    Results are presented of a search for cosmic sources of high-energy neutrinos with the ANTARES neutrino telescope. The data were collected during 2007 and 2008 using detector configurations containing between 5 and 12 detection lines. The integrated live time of the analyzed data is 304 days. Muon tracks are reconstructed using a likelihood-based algorithm. Studies of the detector timing indicate a median angular resolution of 0.5 ± 0.1 deg. The neutrino flux sensitivity is 7.5 × 10-8(E ?/ GeV)-2 GeV-1 s-1 cm-2 for the part of the sky that is always visible (? < -48 deg), which is better than limits obtained by previous experiments. No cosmic neutrino sources have been observed. We dedicate this Letter to the memory of our colleague and friend Luciano Moscoso, who passed away during the preparation of this Letter.

  16. THE HIGH-ENERGY, ARCMINUTE-SCALE GALACTIC CENTER GAMMA-RAY SOURCE

    SciTech Connect

    Chernyakova, M.; Malyshev, D.; Aharonian, F. A. [Dublin Institute for Advanced Study, Astronomy and Astrophysics Section, 31 Fitzwilliam Place, Dublin 2 (Ireland); Crocker, R. M.; Jones, D. I., E-mail: masha@cp.dias.ie [Max Planck Institut fuer Kernphysik, Postfach 103980, 69029 Heidelberg (Germany)

    2011-01-10

    Employing data collected during the first 25 months of observations by the Fermi-LAT, we describe and subsequently seek to model the very high energy (>300 MeV) emission from the central few parsecs of our Galaxy. We analyze the morphological, spectral, and temporal characteristics of the central source, 1FGL J1745.6-2900. The data show a clear, statistically significant signal at energies above 10 GeV, where the Fermi-LAT has angular resolution comparable to that of HESS at TeV energies. This makes a meaningful joint analysis of the data possible. Our analysis of the Fermi data (alone) does not uncover any statistically significant variability of 1FGL J1745.6-2900 at GeV energies on the month timescale. Using the combination of Fermi data on 1FGL J1745.6-2900 and HESS data on the coincident, TeV source HESS J1745-290, we show that the spectrum of the central gamma-ray source is inflected with a relatively steep spectral region matching between the flatter spectrum found at both low and high energies. We model the gamma-ray production in the inner 10 pc of the Galaxy and examine cosmic ray (CR) proton propagation scenarios that reproduce the observed spectrum of the central source. We show that a model that instantiates a transition from diffusive propagation of the CR protons at low energy to almost rectilinear propagation at high energies can explain well the spectral phenomenology. We find considerable degeneracy between different parameter choices which will only be broken with the addition of morphological information that gamma-ray telescopes cannot deliver given current angular resolution limits. We argue that a future analysis performed in combination with higher-resolution radio continuum data holds out the promise of breaking this degeneracy.

  17. Fermi Gamma-ray Space Telescope: High-Energy Results from the First Year

    E-print Network

    Peter F. Michelson; William B. Atwood; Steven Ritz

    2010-11-02

    The Fermi Gamma-ray Space Telescope (Fermi) was launched on June 11, 2008 and began its first year sky survey on August 11, 2008. The Large Area Telescope (LAT), a wide field-of-view pair-conversion telescope covering the energy range from 20 MeV to more than 300 GeV, is the primary instrument on Fermi. While this review focuses on results obtained with the LAT, the Gamma-ray Burst Monitor (GBM) complements the LAT in its observations of transient sources and is sensitive to X-rays and gamma-rays with energies between 8 keV and 40 MeV. During the first year in orbit, the Fermi LAT has observed a large number of sources that include active galaxies, pulsars, compact binaries, globular clusters, supernova remnants, as well as the Sun, the Moon and the Earth. The GBM and LAT together have uncovered surprising characteristics in the high-energy emission of gamma-ray bursts (GRBs) that have been used to set significant new limits on violations of Lorentz invariance. The Fermi LAT has also made important new measurements of the Galactic diffuse radiation and has made precise measurements of the spectrum of cosmic-ray electrons and positrons from 20 GeV to 1 TeV.

  18. Very high energy ?-ray emission from RBS 0679

    NASA Astrophysics Data System (ADS)

    Brown, Anthony M.; Chadwick, Paula M.; Landt, Hermine

    2014-12-01

    In this paper, we report the Fermi Large Area Telescope (LAT) detection of Very High Energy (VHE; E? > 100 GeV) ?-ray emission from the BL Lac object RBS 0679. 5.3 years of LAT observations revealed the presence of three VHE photon events within 0.1° of RBS 0679, with a subsequent unbinned likelihood analysis finding RBS 0679 to be a source of VHE photons at 6.9 standard deviations (?). An unbinned likelihood analysis of the 0.1-100 GeV data, binned in 28-d periods, finds both the flux and spectral index to be variable, with a `softer-when-brighter' trend in the global ?-ray characteristics. On the other hand, the 28-d periods in which the VHE photons were detected have spectral indices that are consistent with the 5.3 year average suggesting that the observed VHE emission is not associated with a spectral hardening event. The discovery of RBS 0679 in the 100-300 GeV energy range, combined with the non-detection above 390 GeV with the H.E.S.S. telescope array, suggest RBS 0679 to be an intriguing source that requires further follow-up observations with ground-based ?-ray observatories.

  19. Primary Cosmic Rays Composition: Simulations and Detector Design

    SciTech Connect

    Supanitsky, D.; Etchegoyen, A.; Medina, C. [Laboratorio Tandar, CNEA Av. Del Libertador 8250, Buenos Aires (Argentina); Medina-Tanco, G. [Instituto Astronomico e Geofisico, Univ. Sao Paulo Rua do Matao 1226, Sao Pablo (Brazil); Gomez Berisso, M. [Instituto Balseiro, Centro Atomico Bariloche/CNEA San Carlos de Bariloche (Argentina)

    2007-02-12

    The Pierre Auger Observatory is a hybrid detector system for the detection of very high energy cosmic rays. A most difficult and important problem in these studies is the determination of the primary cosmic ray composition for which muon content in air showers appears to be one of the best parameters to discriminate between different composition types.Although the Pierre Auger surface detectors, which consist of water Cherenkov tanks, are sensitive to muon content they are not able to measure the number of muons directly. In this work we study using simulations the information that can be gained by adding muon detectors to the Auger surface detectors. We consider muon counters with two alternative areas.

  20. Ankle phenomenon in the cosmic ray energy spectrum

    E-print Network

    Yukio Tomozawa

    2012-08-22

    The author has suggested that the knee phenomenon in the cosmic ray energy spectrum at 3 PeV can be explained as a split between a radiation-dominated expansion and a matter-dominated expansion of an expanding heat bath. The model proposed in 1985, in fact, predicted that high energy cosmic rays are emitted from AGN, massive black holes, in agreement with recent data from the Pierre Auger Observatory. Similarly, the ankle phenomenon at 3 EeV is shown to be explained by a split between inflational expansion and ordinary material expansion of the expanding heat bath, not unlike that in the expansion of the universe. All the spectral indicies in the respective regions of the energy spectra agree with the theoretical calculation from the respective expansion rates.

  1. High altitude cosmic ray research on Tibet highland

    NASA Astrophysics Data System (ADS)

    Tan, Youheng

    2003-12-01

    With the development of ?-ray astronomy, a cosmic ray observatory was founded in the Yangbajing valley of Tibet highland (4300 m.a.s.l.) 10 years ago. Its EAS array of China-Japan AS? Collaboration detected successfully the steady emission of multi-TeV ? rays from the Crab Nebula, the strong outbursts from AGN Mrk 501 in 1997 and from Mrk 421 in 2000, which is the first detection in the EAS experiments. The deviation and movement of Sun shadow by cosmic rays induced by solar and interplanetary magnetic field, has been only observed and will be adopted to monitor the variations of solar activity. Taking the advantages of high altitude and the combination of experiments of EAS array and emulsion chambers + burst detectors, the primary energy spectrum and composition of ultra-high energy cosmic ray have been studied. For exploring the 100 GeV gap region between the space and ground-based experiments, the project of China-Italy ARGO Collaboration is under constructing. Finally, to challenge the 5 GeV low threshold and the highly variable extragalactic sources, a high altitude huge IACT project 5@YorG in the future is discussed.

  2. Contributions to the 19th International Cosmic Ray Conference

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Various aspects of cosmic radiation, its measurements and their patterns are presented. Measurement techniques and variations in solar cosmic ray patterns and calculations of elemental abundances are reviewed.

  3. 27Fermi Observatory and the Origin of Cosmic Rays Cosmic rays are fast-moving particles

    E-print Network

    Observatory has studied the gamma rays that comes from the remains of two nearby supernovae called IC-443 and W44, and has confirmed that the expanding matter does produce cosmic rays. IC-443 supernova remnant

  4. Muon Production in Relativistic Cosmic-Ray Interactions

    SciTech Connect

    Klein, Spencer

    2009-07-27

    Cosmic-rays with energies up to 3x1020 eV have been observed. The nuclear composition of these cosmic rays is unknown but if the incident nuclei are protons then the corresponding center of mass energy is sqrt snn = 700 TeV. High energy muons can be used to probe the composition of these incident nuclei. The energy spectra of high-energy (> 1 TeV) cosmic ray induced muons have been measured with deep underground or under-ice detectors. These muons come from pion and kaon decays and from charm production in the atmosphere. Terrestrial experiments are most sensitive to far-forward muons so the production rates aresensitive to high-x partons in the incident nucleus and low-x partons in the nitrogen/oxygen targets. Muon measurements can complement the central-particle data collected at colliders.This paper will review muon production data and discuss some non-perturbative (soft) models that have been used to interpret the data. I will show measurements of TeV muon transverse momentum (pT) spectra in cosmic-ray air showers fromMACRO, and describe how the IceCube neutrino observatory and the proposed Km3Net detector will extend these measurements to a higher pT region where perturbative QCD should apply. With a 1 km2 surface area, the full IceCube detector should observe hundreds of muons/year with pT in the pQCD regime.

  5. A large detector for cosmic ray abundance and energy measurements

    NASA Astrophysics Data System (ADS)

    Alsop, C.

    A large aperture, balloon borne cosmic ray detector was designed to measure the energy spectra of individual cosmic ray species with Z greater than 8 in the energy range 0.3GeV/N to 400GeV/N. The energy dependence of the abundance spectrum extending up to such high energies will provide valuable data for determining the nature of the origin and propagation of cosmic rays in the Galaxy. The properties of cosmic ray nuclei and the interpretation of the energy dependence of the abundance spectrum are discussed. The design and response of the BUGS IV cosmic ray detector are described. The measurement techniques used are gas scintillation, gas proportional scintillation and Cerenkov radiation from both gases and solids. The light collection properties of the detector and several experimental investigations of the light collection efficiency of the drift chamber region are described. The expected signals from the gas scintillation and gas Cerenkov emissions are predicted and the choice of a suitable scintillating gas mixture for minimizing the uncertainty in the charge and energy measurements is considered. The theoretical aspects of electron drift and diffusion in gases and several experimental investigations on the electron drift in the BUGS IV drift chamber are given. Also some preliminary results from a uniform field drift chamber are included which demonstrate the sensitivity of the electron drift velocity in inert gas mixtures to water vapor contamination. The expected overall performance of BUGS IV and the results of an experimental simulation of the parachute landing of the detector are given.

  6. Implications of a possible clustering of highest-energy?cosmic?rays

    PubMed Central

    Sigl, Günter; Schramm, David N.; Lee, Sangjin; Hill, Christopher T.

    1997-01-01

    Recently, a possible clustering of a subset of observed ultra-high energy cosmic rays above ?40 EeV (4 × 1019 eV) in pairs near the supergalactic plane was reported. We show that a confirmation of this effect would provide information on the origin and nature of these events and, in case of charged primaries, imply interesting constraints on the extragalactic magnetic field. Possible implications for the most common models of ultra-high energy cosmic ray production in the literature are discussed. PMID:11038576

  7. All-Union Conference on Cosmic Rays, Dagomys, Russia, Nov. 1-3, 1990, Proceedings

    NASA Astrophysics Data System (ADS)

    1991-10-01

    The present conference on cosmic rays discusses features of the ground-level solar cosmic ray intensity increase on September 28, 1989, from neutron monitor data, large solar proton events at the beginning of the 22nd solar cycle, the solar cosmic ray maximum during the 22nd cycle, and the solar cosmic ray flare in March of 1990. Topics addressed include radiation dynamics along the Mir spacecraft route during the solar proton event of September 29, 1989, accelerated particle dynamics in flare loops, the seasonal behavior of the daily intensities of muons with E not less than 220 GeV, and cosmic ray anisotropy and gradient in different structures of solar wind. Also examined are high-energy electron and positron energy spectra under the earth's radiation belt, Galactic cosmic ray intensity during the beginning of the sun's global magnetic field reversal, the propagation of cosmic rays in the magnetic field with large-scale inhomogeneities, and north-south asymmetry of the nonperiodic and quasi-periodic cosmic ray variations.

  8. Astrophysics of Galactic charged cosmic rays

    E-print Network

    Antonella Castellina; Fiorenza Donato

    2011-10-13

    A review is given of the main properties of the charged component of galactic cosmic rays, particles detected at Earth with an energy spanning from tens of MeV up to about 10^19 eV. After a short introduction to the topic and an historical overview, the properties of cosmic rays are discussed with respect to different energy ranges. The origin and the propagation of nuclei in the Galaxy are dealt with from a theoretical point of view. The mechanisms leading to the acceleration of nuclei by supernova remnants and to their subsequent diffusion through the inhomogeneities of the galactic magnetic field are discussed and some clue is given on the predictions and observations of fluxes of antimatter, both from astrophysical sources and from dark matter annihilation in the galactic halo. The experimental techniques and instrumentations employed for the detection of cosmic rays at Earth are described. Direct methods are viable up to 10^14 eV, by means of experiments flown on balloons or satellites, while above that energy, due to their very low flux, cosmic rays can be studied only indirectly by exploiting the particle cascades they produce in the atmosphere. The possible physical interpretation of the peculiar features observed in the energy spectrum of galactic cosmic rays, and in particular the so-called "knee" at about 4x10^15 eV, are discussed. A section is devoted to the region between about 10^18 and 10^19 eV, which is believed to host the transition between galactic and extragalactic cosmic rays. The conclusion gives some perspectives on the cosmic ray astrophysics field. Thanks to a wealth of different experiments, this research area is living a very flourishing era. The activity is exciting both from the theoretical and the instrumental sides, and its interconnection with astronomy, astrophysics and particle physics experiences non-stop growth.

  9. High-Energy Spectral Signatures in Gamma-Ray Bursts

    NASA Technical Reports Server (NTRS)

    Baring, Matthew G.

    2000-01-01

    One of the principal results obtained by the EGRET experiment aboard the Compton Gamma-Ray Observatory (CGRO) was the detection of several gamma-ray bursts (GRBs) above 100 MeV. The broad-band spectra obtained for these bursts gave no indication of any high energy spectral attenuation that might preclude detection of bursts by ground-based Cerenkov telescopes (ACTs), thus motivating several TeV observational programs. This paper explores the expectations for the spectral properties in the TeV and sub-TeV bands for bursts, in particular how attenuation of photons by pair creation internal to the source modifies the spectrum to produce distinctive spectral signatures. The energy of spectral breaks and the associated spectral indices provide valuable information that can constrain the bulk Lorentz factor of the GRB outflow at a given time. These characteristics define palpable observational goals for ACT programs, and strongly impact the observability of bursts in the TeV band.

  10. High-Energy Spectral Signatures in Gamma-Ray Bursts

    NASA Technical Reports Server (NTRS)

    Baring, Matthew D.

    1999-01-01

    One of the principal results obtained by the EGRET experiment aboard the Compton Gamma-Ray Observatory (CGRO) was the detection of several gamma-ray bursts (GRBs) above 100 MeV. The broad-band spectra obtained for these bursts gave no indication of any high-energy spectral attenuation that might preclude detection of bursts by ground-based Cerenkov telescopes (ACTs), thus motivating several TeV observational programs. This paper explores the expectations for the spectral properties in the TeV and sub-TeV bands for bursts, in particular how attenuation of photons by pair creation internal to the source modifies the spectrum to produce distinctive spectral signatures. The energy of spectral breaks and the associated spectral indices provide valuable information that can constrain the bulk Lorentz factor of the GRB outflow at a given time. These characteristics define palpable observational goals for ACT programs, and strongly impact the observability of bursts in the TeV band.

  11. Positron fraction in cosmic rays and models of cosmic-ray propagation

    NASA Astrophysics Data System (ADS)

    Cowsik, R.; Burch, B.

    2010-07-01

    The positron fraction observed by PAMELA and other experiments up to ˜100GeV is analyzed in terms of models of cosmic-ray propagation. It is shown that generically we expect the positron fraction to reach ˜0.6 at energies of several TeV, and its energy dependence bears an intimate but subtle connection with that of the boron to carbon ratio in cosmic rays. The observed positron fraction can be fit in a model that assumes a significant fraction of the boron below ˜10GeV is generated through spallation of cosmic-ray nuclei in a cocoonlike region surrounding the sources, and the positrons of energy higher than a few GeV are almost exclusively generated through cosmic-ray interactions in the general interstellar medium. Such a model is consistent with the bounds on cosmic-ray anisotropies and other observations.

  12. PROMPT HIGH-ENERGY EMISSION FROM PROTON-DOMINATED GAMMA-RAY BURSTS

    SciTech Connect

    Asano, Katsuaki [Interactive Research Center of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan); Inoue, Susumu [Department of Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan); Meszaros, Peter [Department of Astronomy and Astrophysics, Department of Physics, Center for Particle Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)], E-mail: asano@phys.titech.ac.jp, E-mail: inoue@tap.scphys.kyoto-u.ac.jp, E-mail: nnp@astro.psu.edu

    2009-07-10

    The prompt emission of gamma-ray bursts (GRBs) is widely thought to be radiation from accelerated electrons, but an appreciably larger amount of energy could be carried by accelerated protons, particularly if GRBs are the sources of ultra-high-energy cosmic rays (UHECRs). We model the expected photon spectra for such 'proton-dominated' GRBs in the internal shock scenario through Monte Carlo simulations, accounting for various processes related to high-energy electrons and protons. Besides proton and muon synchrotron components, emission from photomeson-induced secondary pair cascades becomes crucial, generally enhancing the GeV-TeV and/or eV-keV photons and offering a signature of UHE protons. In some cases, it can overwhelm the primary electron component and result in GRBs peaking in the 10 MeV-1 GeV range, which may be relevant to some bursts discussed in a recent re-analysis of EGRET TASC data. The dependence of the spectra on key quantities such as the bulk Lorentz factor, magnetic field, and proton-to-electron ratio is nontrivial due to the nonlinear nature of cascading and the interplay of electron- and proton-induced components. Observations by Fermi, ground-based telescopes, and other facilities should test these expectations and provide critical constraints on the proton acceleration efficiency.

  13. High energy neutrinos from gamma-ray bursts: Recent observations and models

    NASA Astrophysics Data System (ADS)

    Gao, Shan

    Neutrino astronomy began with the detection of solar neutrinos, supernova neutrinos (SN1987A) and more recently the 37 events in IceCube which are very likely to be an astrophysical origin. The result from IceCube is perhaps the most exciting discovery of the year 2013, capping a several decades long search. Various astrophysical candidates have been proposed as sources of high energy neutrinos, although the origin of the IceCube neutrinos remains a mystery. Gamma-ray bursts (GRBs), the most energetic explosions in the universe, were considered as the most promising source for high energy cosmic rays and neutrinos (with AGNs). However, a previous search of GRB neutrinos by IceCube surprised the GRB community with negative results, challenging the simple standard picture of GRB prompt emission which is called the internal shock" model. In this thesis we give a closer investigation of this model as well as several leading alternative models. With a careful consideration of the particle physics and the model parameters we show that the previous negative result with GRB neutrinos is not surprising, and only those models with extremely optimistic parameters can be ruled out. We predict that GRBs are unlikely to be the sole sources of the IceCube events, but signals of GRB neutrinos may be detected in the near future, with the neutrino telescopes such as IceCube/DeepCore, KM3Net, ARA, ARIANNA, ANITA etc.

  14. Hard X-ray and Gamma-ray Emission Induced by Ultra-High Energy Protons in Cluster Accretion Shocks

    E-print Network

    Susumu Inoue; Felix A. Aharonian; Naoshi Sugiyama

    2005-06-05

    All sufficiently massive clusters of galaxies are expected to be surrounded by strong accretion shocks, where protons can be accelerated to $\\sim 10^{18}$-$10^{19}$ eV under plausible conditions. Such protons interact with the cosmic microwave background and efficiently produce very high energy electron-positron pairs, which then radiate synchrotron and inverse Compton emission, peaking respectively at hard X-ray and TeV gamma-ray energies. Characterized by hard spectra (photon indices $\\sim 1.5$) and spatial distribution tracing the accretion shock, these can dominate over other nonthermal components depending on the shock magnetic field. HESS and other Cerenkov telescopes may detect the TeV emission from nearby clusters, notwithstanding its extended nature. The hard X-rays may be observable by future imaging facilities such as NeXT, and possibly also by ASTRO-E2/HXD. Such detections will not only provide a clear signature of ultra-high energy proton acceleration, but also an important probe of the accretion shock itself as well as magnetic fields in the outermost regions of clusters.

  15. Very high-energy gamma rays from gamma-ray bursts.

    PubMed

    Chadwick, Paula M

    2007-05-15

    Very high-energy (VHE) gamma-ray astronomy has undergone a transformation in the last few years, with telescopes of unprecedented sensitivity having greatly expanded the source catalogue. Such progress makes the detection of a gamma-ray burst at the highest energies much more likely than previously. This paper describes the facilities currently operating and their chances for detecting gamma-ray bursts, and reviews predictions for VHE gamma-ray emission from gamma-ray bursts. Results to date are summarized. PMID:17293337

  16. Cosmic-ray composition and muon decoherence at the knee of the all-particle cosmic-ray spectrum

    SciTech Connect

    Kieda, D.B.

    1989-01-01

    The charge resolved cosmic ray energy spectrum provides important clues for determining the origin of these particles. High energy muons, created by primary nuclei in extensive air showers, exhibit sensitivity to the atomic mass of the progenitor nucleus. Using the Homestake Liquid Scintillation Hodoscope, the author has examined the rates and mutiplicity distribution of high energy muons (E{mu} > 2.6 TeV) for sensitivity to primary composition in the 10{sup 14}-10{sup 16} eV energy range. The primary composition is determined from a comparison of the measured muon multiplicity spectrum with the spectrum predicted by various primary composition models. The primary composition determined from an energy independent two component fit contains 83 {+-} 13% protons and 17% iron. In terms of energy dependent models, the multiple muon rates are in good agreement with a proton dominated primary composition, as proposed by Fichtel and Linsely. The iron enriched Maryland II composition does not provide a good fit to the experimental data. Muon pair separation rates are examined to measure the (P{sub T}) of secondary pions created in high energy nucleus-nucleus collisions. The muon pair decoherence is measured over zenith angle ranges of 0{degree}-20{degree}, 20{degree}-40{degree}, and 40{degree}-60{degree}, corresponding to mean interaction energies of 480, 580, and 820 GeV, respectively. The measured (P{sub T}) is slightly larger than recent p-p interaction accelerator results, but is consistent with previous cosmic ray results.

  17. Neutrino, Neutron, and Cosmic Ray Production in the External Shock Model of Gamma Ray Bursts

    E-print Network

    Charles D. Dermer

    2002-04-16

    The hypothesis that ultra-high energy (>~ 10^19 eV) cosmic rays (UHECRs) are accelerated by gamma-ray burst (GRB) blast waves is assumed to be correct. Implications of this assumption are then derived for the external shock model of gamma-ray bursts. The evolving synchrotron radiation spectrum in GRB blast waves provides target photons for the photomeson production of neutrinos and neutrons. Decay characteristics and radiative efficiencies of the neutral particles that escape from the blast wave are calculated. The diffuse high-energy GRB neutrino background and the distribution of high-energy GRB neutrino events are calculated for specific parameter sets, and a scaling relation for the photomeson production efficiency in surroundings with different densities is derived. GRBs provide an intense flux of high-energy neutrons, with neutron-production efficiencies exceeding ~ 1% of the total energy release. The radiative characteristics of the neutron beta-decay electrons from the GRB "neutron bomb" are solved in a special case. Galaxies with GRB activity should be surrounded by radiation halos of ~ 100 kpc extent from the outflowing neutrons, consisting of a nonthermal optical/X-ray synchrotron component and a high-energy gamma-ray component from Compton-scattered microwave background radiation. The luminosity of sources of GRBs and relativistic outflows in L* galaxies such as the Milky Way is at the level of ~10^40+-1 ergs/s. This is sufficient to account for UHECR generation by GRBs. We briefly speculate on the possibility that hadronic cosmic rays originate from the subset of supernovae that collapse to form relativistic outflows and GRBs. (abridged)

  18. Pion Production Momentum Loss of Cosmic Ray Hadrons

    NASA Astrophysics Data System (ADS)

    Krakau, S.; Schlickeiser, R.

    2015-04-01

    We present new results on the energy loss rate of high energy protons due to pion production in proton–proton interactions. Our calculations are based on the parameterized pion flux of Kelner et al. Our new results are valid for proton energies in the range of 1 GeV \\ll E?slant {{10}8} GeV, which enhance the valid energy range by orders of magnitude. With these results one can calculate the energy loss due to pion production for cosmic ray protons from low energies to energies between the knee and ankle.

  19. SPECTRUM OF GALACTIC COSMIC RAYS ACCELERATED IN SUPERNOVA REMNANTS

    SciTech Connect

    Ptuskin, Vladimir; Zirakashvili, Vladimir [Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of Science (IZMIRAN), Troitsk, Moscow Region 142190 (Russian Federation); Seo, Eun-Suk [Department of Physics and Institute of Physical Science and Technology, University of Maryland, College Park, MD 20742 (United States)

    2010-07-20

    The spectra of high-energy protons and nuclei accelerated by supernova remnant (SNR) shocks are calculated, taking into account magnetic field amplification and Alfvenic drift both upstream and downstream of the shock for different types of SNRs during their evolution. The maximum energy of accelerated particles may reach 5 x 10{sup 18} eV for Fe ions in Type IIb SNRs. The calculated energy spectrum of cosmic rays after propagation through the Galaxy is in good agreement with the spectrum measured at the Earth.

  20. Cosmic Rays, Gamma-Rays, & Neutrinos in the Starburst Nuclei of Arp 220

    E-print Network

    Yoast-Hull, Tova M; Zweibel, Ellen G

    2015-01-01

    The cores of Arp 220, the closest ultra-luminous infrared starburst galaxy, provide an opportunity to study interactions of cosmic rays under extreme conditions. In this paper, we model the populations of cosmic rays produced by supernovae in the central molecular zones of both starburst nuclei. We find that ~65 - 100% of cosmic rays are absorbed in these regions due to their huge molecular gas contents, and thus, the nuclei of Arp 220 nearly complete proton calorimeters. As the cosmic ray protons collide with the interstellar medium, they produce secondary electrons that are also contained within the system and radiate synchrotron emission. Using results from chi-squared tests between the model and the observed radio spectral energy distribution, we predict the emergent gamma-ray and high-energy neutrino spectra and find the magnetic field to be at milligauss levels. Because of the extremely intense far-infrared radiation fields, the gamma-ray spectrum steepens significantly at TeV energies due to gamma-gamm...

  1. Cosmic Ray Interactions in Shielding Materials

    SciTech Connect

    Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Ankney, Austin S.; Orrell, John L.; Berguson, Timothy J.; Troy, Meredith D.

    2011-09-08

    This document provides a detailed study of materials used to shield against the hadronic particles from cosmic ray showers at Earth’s surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during transport for the MAJORANA collaboration. The materials suitable for cosmic-ray shield design are materials such as lead and iron that will stop the primary protons, and materials like polyethylene, borated polyethylene, concrete and water that will stop the induced neutrons. The interaction of the different cosmic-ray components at ground level (protons, neutrons, muons) with their wide energy range (from kilo-electron volts to giga-electron volts) is a complex calculation. Monte Carlo calculations have proven to be a suitable tool for the simulation of nucleon transport, including hadron interactions and radioactive isotope production. The industry standard Monte Carlo simulation tool, Geant4, was used for this study. The result of this study is the assertion that activation at Earth’s surface is a result of the neutronic and protonic components of the cosmic-ray shower. The best material to shield against these cosmic-ray components is iron, which has the best combination of primary shielding and minimal secondary neutron production.

  2. Monopole Annihilation and Highest Energy Cosmic Rays

    E-print Network

    P. Bhattacharjee; G. Sigl

    1994-12-15

    Cosmic rays with energies exceeding $10^{20}\\eV$ have been detected. The origin of these highest energy cosmic rays remains unknown. Established astrophysical acceleration mechanisms encounter severe difficulties in accelerating particles to these energies. Alternative scenarios where these particles are created by the decay of cosmic topological defects have been suggested in literature. In this paper we study the possibility of producing the highest energy cosmic rays through a process that involves formation of metastable magnetic monopole-antimonopole bound states and their subsequent collapse. The annihilation of the heavy monopole-antimonopole pairs constituting the monopolonia can produce energetic nucleons, gamma rays and neutrinos whose expected flux we estimate and discuss in relation to experimental data so far available. The monopoles we consider are the ones that could be produced in the early universe during a phase transition at the grand unification energy scale. We find that observable cosmic ray fluxes can be produced with monopole abundances compatible with present bounds.

  3. Cosmic Ray Nuclei (CRN) detector investigation

    NASA Technical Reports Server (NTRS)

    Meyer, Peter; Muller, Dietrich; Lheureux, Jacques; Swordy, Simon

    1991-01-01

    The Cosmic Ray Nuclei (CRN) detector was designed to measure elemental composition and energy spectra of cosmic radiation nuclei ranging from lithium to iron. CRN was flown as part of Spacelab 2 in 1985, and consisted of three basic components: a gas Cerenkov counter, a transition radiation detector, and plastic scintillators. The results of the experiment indicate that the relative abundance of elements in this range, traveling at near relativistic velocities, is similar to those reported at lower energy.

  4. Effect of energy deposited by cosmic-ray particles on interferometric gravitational wave detectors

    E-print Network

    Kazuhiro Yamamoto; Hideaki Hayakawa; Atsushi Okada; Takashi Uchiyama; Shinji Miyoki; Masatake Ohashi; Kazuaki Kuroda; Nobuyuki Kanda; Daisuke Tatsumi; Yoshiki Tsunesada

    2008-08-03

    We investigated the noise of interferometric gravitational wave detectors due to heat energy deposited by cosmic-ray particles. We derived a general formula that describes the response of a mirror against a cosmic-ray passage. We found that there are differences in the comic-ray responses (the dependence of temperature and cosmic-ray track position) in cases of interferometric and resonant gravitational wave detectors. The power spectral density of vibrations caused by low-energy secondary muons is 100-times smaller than the goal sensitivity of future second-generation interferometer projects, such as LCGT and Advanced LIGO. The arrival frequency of high-energy cosmic-ray muons that generate enough large showers inside mirrors of LCGT and Advanced LIGO is one per a millennium. We also discuss the probability of exotic-particle detection with interferometers.

  5. Low-energy cosmic rays in the Orion region

    Microsoft Academic Search

    Martin Pohl

    1998-01-01

    The recently observed nuclear ?-ray line emission from the Orion complex implies a high flux of low-energy cosmic rays (LECR) with unusual abundance. This cosmic ray component would dominate the energy density, pressure, and ionising power of cosmic rays, and thus would have a strong impact on the general structure of the interstellar medium. We propose an independent test for

  6. The Highest Energy Cosmic Rays and Gamma Rays

    Microsoft Academic Search

    S. F. Taylor; T. Abu-Zayyad; K. Belov; Z. Cao; G. Chen; M. A. Huang; C. C. H. Jui; D. B. Kieda; E. C. Loh; J. N. Matthews; M. Salamon; A. Salman; J. D. Smith; P. Sokolsky; P. Sommers; S. B. Thomas; L. R. Wiencke; D. J. Bird; R. W. Clay; B. R. Dawson; K. M. Simpson; C. R. Wilkinson; J. Boyer; E. J. Mannel; Y. Ho; W. Lee; T. O'Halloran; N. Hayashida; H. Hirasawa; F. Ishikawa; H. Lafoux; M. Nagano; D. Nishikawa; T. Ouchi; H. Ohoka; M. Ohnishi; N. Sakaki; M. Sasaki; H. Shimodaira; M. Teshima; R. Torii; T. Yamamoto; S. Yoshida; T. Yuda

    1998-01-01

    Taking advantage of the dark skies near Dugway, Utah, the University of Utah's Fly's Eye Detector has been observing cosmic rays with energies above 3x 10(16) eV by detecting light from the nitrogen fluorescence from the Extensive Air Showers produced by cosmic rays. The detection of an event measured to have 3x 10(20) eV raises the question of whether the

  7. Model-dependent high-energy neutrino flux from gamma-ray bursts.

    PubMed

    Zhang, Bing; Kumar, Pawan

    2013-03-22

    The IceCube Collaboration recently reported a stringent upper limit on the high energy neutrino flux from gamma-ray bursts (GRBs), which provides a meaningful constraint on the standard internal shock model. Recent broadband electromagnetic observations of GRBs also challenge the internal shock paradigm for GRBs, and some competing models for ?-ray prompt emission have been proposed. We describe a general scheme for calculating the GRB neutrino flux, and compare the predicted neutrino flux levels for different models. We point out that the current neutrino flux upper limit starts to constrain the standard internal shock model. The dissipative photosphere models are also challenged if the cosmic ray luminosity from GRBs is at least 10 times larger than the ?-ray luminosity. If the neutrino flux upper limit continues to go down in the next few years, then it would suggest the following possibilities: (i) the photon-to-proton luminosity ratio in GRBs is anomalously high for shocks, which may be achieved in some dissipative photosphere models and magnetic dissipation models; or (ii) the GRB emission site is at a larger radius than the internal shock radius, as expected in some magnetic dissipation models such as the internal collision-induced magnetic reconnection and turbulence model. PMID:25166786

  8. From cosmic ray physics to cosmic ray astronomy: Bruno Rossi and the opening of new windows on the universe

    NASA Astrophysics Data System (ADS)

    Bonolis, Luisa

    2014-01-01

    Bruno Rossi is considered one of the fathers of modern physics, being also a pioneer in virtually every aspect of what is today called high-energy astrophysics. At the beginning of 1930s he was the pioneer of cosmic ray research in Italy, and, as one of the leading actors in the study of the nature and behavior of the cosmic radiation, he witnessed the birth of particle physics and was one of the main investigators in this fields for many years. While cosmic ray physics moved more and more towards astrophysics, Rossi continued to be one of the inspirers of this line of research. When outer space became a reality, he did not hesitate to leap into this new scientific dimension. Rossi's intuition on the importance of exploiting new technological windows to look at the universe with new eyes, is a fundamental key to understand the profound unity which guided his scientific research path up to its culminating moments at the beginning of 1960s, when his group at MIT performed the first in situ measurements of the density, speed and direction of the solar wind at the boundary of Earth's magnetosphere, and when he promoted the search for extra-solar sources of X rays. A visionary idea which eventually led to the breakthrough experiment which discovered Scorpius X-1 in 1962, and inaugurated X-ray astronomy.

  9. Did Cosmic Rays Reionize the Intergalactic Medium?

    E-print Network

    Biman B. Nath; Peter L. Biermann

    1993-06-02

    We investigate the role of cosmic rays from young galaxies in heating and ionizing the intergalactic medium (IGM) at high redshift. Using the IRAS observations at $60 \\mu m$, we estimate the cosmic ray luminosity density at the present epoch. We consider various forms of luminosity evolution in redshift and calculate (a) the thresholds corresponding to the upper limits of Gunn-Peterson optical depth, (b) the Compton $y$ parameter for an IGM heated by cosmic rays and compare with the upper limits from COBE measurements and (c) an estimated limit from the integral of metal enrichment. We show that certain models, with rather strong evolution and early formation of galaxies, allow reionization of the IGM, consistent with all known constraints.

  10. Cosmic ray ionization of the interstellar medium

    E-print Network

    Biman B. Nath; Peter L. Biermann

    1993-11-18

    We consider a cosmic ray spectrum that is a power law in momentum down to a cutoff and derive a lower cutoff corresponding to $E_{kin} \\sim (30-60)$ MeV from the observed ionization rates in nearby diffuse clouds. While the real spectra of cosmic rays may not be so simple, we argue that one expects a substantial change in the spectra at such energies and that, at first approximation, a power law spectra with a lower cutoff is appropriate. Such a description of the cosmic rays in the interstellar medium is not only theoretically more attractive than the spectra used in the literature, but is also supported by recent observations.

  11. Cosmic ray interactions with the Venusian atmosphere

    NASA Astrophysics Data System (ADS)

    Plainaki, Christina; Paschalis, Pavlos; Grassi, Davide; Mavromichalaki, Helen; Andriopoulou, Maria

    2015-04-01

    The interactions between galactic cosmic ray particles and the atmosphere of Venus result in extensive nuclear and electromagnetic cascades that can affect cloud formation and atmospheric physics in deep atmospheric layers. In this work, we perform a calculation of the atmosphere ionization and ion production rates caused by cosmic rays, as a function of depth in the Venusian atmosphere. In order to perform this estimation, we use a Monte Carlo modeling technique based on the Geant4 software, previously applied for the Earth case; our predictions are afterwards compared to other estimations derived from previous studies. The current method is furthermore proposed as a paradigm for studying cosmic rays-atmosphere interactions in all terrestrial planets possessing atmospheres.

  12. The Interstellar Transport of Galactic Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Lave, Kelly A.

    Using the Cosmic Ray Isotope Spectrometer (CRIS) onboard the Advanced Composition Explorer (ACE) spacecraft, new and improved high-precision measurements of the elemental composition and energy spectra of galactic cosmic rays with energies from ˜50--550 MeV/nucleon and nuclear charge 5?Z?28 are reported here. These results cover observations during two solar minimum periods of the solar cycle, the most recent of which exhibited very low levels of solar activity and the highest galactic cosmic-ray intensities of the space era. Observations of secondary cosmic-ray species, those produced primarily by spallation interactions of accelerated material with the interstellar medium, and their primary progenitors are used to test the models of the transport of cosmic rays in the Galaxy. Two principal models were tested: the simple leaky-box model and the nested leaky-box model. In the simple leaky-box model, cosmic rays accelerated at their sources are transported uniformly through the interstellar medium and escape in an energy-dependent fashion from the Galaxy. In the nested leaky-box model, cosmic rays are accelerated at their sources and briefly stored in surrounding cocoon regions before they escape into the Galaxy; escape from the cocoon regions is energy dependent while escape from the Galaxy is independent of energy. Our observed B/C and (Sc+ Ti+V)/Fe ratios are compared with the results from these two models, and we find that the simple leaky-box model fits the data very well only when escape from the Galaxy has an unphysical energy dependence below ˜1 GeV/nucleon. Though the nested leaky-box model is considered to be more physically reasonable, we could not simultaneously fit the B/C and (Sc+Ti+ V)/Fe ratios at all energies. A model that includes a small amount of reacceleration, a process that boosts low-energy cosmic rays up to higher energies, is found to agree well with results from the simple leaky-box model.

  13. Threshold meson production and cosmic ray transport

    E-print Network

    John W. Norbury; Lawrence W. Townsend; Ryan B. Norman

    2006-12-11

    An interesting accident of nature is that the peak of the cosmic ray spectrum, for both protons and heavier nuclei, occurs near the pion production threshold. The Boltzmann transport equation contains a term which is the cosmic ray flux multiplied by the cross section. Therefore when considering pion and kaon production from proton-proton reactions, small cross sections at low energy can be as important as larger cross sections at higher energy. This is also true for subthreshold kaon production in nuclear collisions, but not for subthreshold pion production.

  14. Cosmic ray modulation inside stellar wind cavities

    NASA Astrophysics Data System (ADS)

    Van Der Schyff, August; Scherer, Klaus; Ferreira, Stefan; Toit Strauss, Du

    In this study we attempt to model the cosmic ray flux in a stellar wind cavity of a O or B type star using a transport model based on stochastic differential equations. The required parameters, for example the coefficients of the diffusion tensor, are determined from an underlying magneto-hydrodynamical model. We discuss the transport in different astrospheric models with varying parameters for the transport coefficients. We will argue that large stellar wind cavities can act as sinks for the galactic cosmic ray flux.

  15. Cosmic Ray physics with ARGO-YBJ

    NASA Astrophysics Data System (ADS)

    Iacovacci, M.

    2013-06-01

    The ARGO-YBJ experiment has been in stable data taking from November 2007 till February 2013 at the Yang-BaJing Cosmic Ray Laboratory (Tibet, P.R.China, 4300 m a.s.l.). It exploits the full coverage and the high altitude to detect air showers with an energy threshold as low as a few hundred GeV. The detector is made of a single layer of RPCs operated in streamer mode, fully instrumenting a central carpet of about 5800 m. A guard ring extends the partially instrumented area to about 11,000 m. The main results so far achieved on Cosmic Ray physics are reported.

  16. Observation of Polarised Microwave Emission from Cosmic Ray Air Showers

    E-print Network

    Smida, R; Engel, R; Arteaga-Velazquez, J C; Bekk, K; Bertaina, M; Bluemer, J; Bozdog, H; Brancus, I M; Chiavassa, A; Cossavella, F; Di Pierro, F; Doll, P; Fuchs, B; Fuhrmann, D; Grupen, C; Haungs, A; Heck, D; Hoerandel, J R; Huber, D; Huege, T; Kampert, K -H; Kang, D; Klages, H; Kleifges, M; Kroemer, O; Link, K; Luczak, P; Ludwig, M; Mathes, H J; Mayer, H J; Mathys, S; Melissas, M; Morello, C; Neunteufel, P; Oehlschlaeger, J; Palmieri, N; Pekala, J; Pierog, T; Rautenberg, J; Rebel, H; Riegel, M; Roth, M; Salamida, F; Schieler, H; Schoo, S; Schroeder, F G; Sima, O; Stasielak, J; Toma, G; Trinchero, G C; Unger, M; Weber, M; Weindl, A; Wilczynski, H; Will, M; Wochele, J; Zabierowski, J

    2013-01-01

    We report on the first direct measurement of the basic features of microwave radio emission from extensive air showers. Using a trigger provided by the KASCADE-Grande air shower array, the signals of the microwave antennas of the CROME (Cosmic-Ray Observation via Microwave Emission) experiment have been read out and searched for signatures of radio emission by high-energy air showers. Microwave signals have been detected for more than 30 showers with energies above $3\\times10^{16}$\\,eV. The observations presented in this Letter are consistent with a mainly forward-beamed, coherent and polarised emission process in the GHz frequency range. An isotropic, unpolarised radiation is disfavoured as the dominant emission model. The measurements show that microwave radiation offers a new means of studying air showers at very high energy.

  17. Propagation of Cosmic Rays and Diffuse Galactic Gamma Rays

    E-print Network

    I. V. Moskalenko

    2004-10-08

    This paper presents an introduction to the astrophysics of cosmic rays and diffuse gamma rays and discusses some of the puzzles that have emerged recently due to more precise data and improved propagation models: the excesses in Galactic diffuse gamma-ray emission, secondary antiprotons and positrons, and the flatter than expected gradient of cosmic rays in the Galaxy. These also involve the dark matter, a challenge to modern physics, through its indirect searches in cosmic rays. Though the final solutions are yet to be found, I discuss some ideas and results obtained mostly with the numerical propagation model GALPROP. A fleet of spacecraft and balloon experiments targeting these specific issues is set to lift off in a few years, imparting a feeling of optimism that a new era of exciting discoveries is just around the corner. A complete and comprehensive discussion of all the recent results is not attempted here due to the space limitations.

  18. Nineteenth International Cosmic Ray Conference. OG Sessions, Volume 3

    NASA Technical Reports Server (NTRS)

    Jones, F. C. (compiler)

    1985-01-01

    Papers submitted for presentation at the 19th International Cosmic Ray Conference are compiled. This volume addresses cosmic ray sources and acceleration, interstellar propagation and nuclear interactions, and detection techniques and instrumentation.

  19. The Isotopic Composition of Cosmic-Ray Iron and Nickel

    NASA Technical Reports Server (NTRS)

    Wiedenbeck, M.; Binns, W.; Christian, E.; Cummings, A.; George, J.; Hink, P.; Klarmann, J.; Leske, R.; Lijowski, M.; Mewaldt, R.; Stone, E.; Rosenvinge, T. von

    2000-01-01

    Observations from the Cosmic Ray Isotope Spectrometer (CRIS) on ACE have been used to derive contraints on the locations, physical conditions, and time scales for cosmic-ray acceleration and transport.

  20. High Energy Gamma-Ray Emission from Gamma-Ray Bursts - Before GLAST

    SciTech Connect

    Fan, Yi-Zhong; Piran, Tsvi

    2011-11-29

    Gamma-ray bursts (GRBs) are short and intense emission of soft {gamma}-rays, which have fascinated astronomers and astrophysicists since their unexpected discovery in 1960s. The X-ray/optical/radio afterglow observations confirm the cosmological origin of GRBs, support the fireball model, and imply a long-activity of the central engine. The high-energy {gamma}-ray emission (> 20 MeV) from GRBs is particularly important because they shed some lights on the radiation mechanisms and can help us to constrain the physical processes giving rise to the early afterglows. In this work, we review observational and theoretical studies of the high-energy emission from GRBs. Special attention is given to the expected high-energy emission signatures accompanying the canonical early-time X-ray afterglow that was observed by the Swift X-ray Telescope. We also discuss the detection prospect of the upcoming GLAST satellite and the current ground-based Cerenkov detectors.

  1. New Limits on the Ultra-high Energy Cosmic Neutrino Flux from the ANITA Experiment

    E-print Network

    ANITA collaboration; P. Gorham; P. Allison; S. Barwick; J. Beatty; D. Besson; W. Binns; C. Chen; P. Chen; J. Clem; A. Connolly; P. Dowkontt; M. DuVernois; R. Field; D. Goldstein; A. Goodhue; C. Hast; C. Hebert; S. Hoover; M. Israel; J. Kowalski; J. Learned; K. Liewer; J. Link; E. Lusczek; S. Matsuno; B. Mercurio; C. Miki; P. Miocinovic; J. Nam; C. Naudet; R. Nichol; K. Palladino; K. Reil; A. Romero-Wolf; M. Rosen; L. Ruckman; D. Saltzberg; D. Seckel; G. Varner; D. Walz; Y. Wang; F. Wu

    2008-12-15

    We report initial results of the first flight of the Antarctic Impulsive Transient Antenna (ANITA-1) 2006-2007 Long Duration Balloon flight, which searched for evidence of a diffuse flux of cosmic neutrinos above energies of 3 EeV. ANITA-1 flew for 35 days looking for radio impulses due to the Askaryan effect in neutrino-induced electromagnetic showers within the Antarctic ice sheets. We report here on our initial analysis, which was performed as a blind search of the data. No neutrino candidates are seen, with no detected physics background. We set model-independent limits based on this result. Upper limits derived from our analysis rule out the highest cosmogenic neutrino models. In a background horizontal-polarization channel, we also detect six events consistent with radio impulses from ultra-high energy extensive air showers.

  2. High energy particles and quanta in astrophysics

    NASA Technical Reports Server (NTRS)

    Mcdonald, F. B. (editor); Fichtel, C. E.

    1974-01-01

    The various subdisciplines of high-energy astrophysics are surveyed in a series of articles which attempt to give an overall view of the subject as a whole by emphasizing the basic physics common to all fields in which high-energy particles and quanta play a role. Successive chapters cover cosmic ray experimental observations, the abundances of nuclei in the cosmic radiation, cosmic electrons, solar modulation, solar particles (observation, relationship to the sun acceleration, interplanetary medium), radio astronomy, galactic X-ray sources, the cosmic X-ray background, and gamma ray astronomy. Individual items are announced in this issue.

  3. X-ray Observations of Cosmic Ray Acceleration

    NASA Technical Reports Server (NTRS)

    Petre, Robert

    2012-01-01

    Since the discovery of cosmic rays, detection of their sources has remained elusive. A major breakthrough has come through the identification of synchrotron X-rays from the shocks of supernova remnants through imaging and spectroscopic observations by the most recent generation of X-ray observatories. This radiation is most likely produced by electrons accelerated to relativistic energy, and thus has offered the first, albeit indirect, observational evidence that diffusive shock acceleration in supernova remnants produces cosmic rays to TeV energies, possibly as high as the "knee" in the cosmic ray spectrum. X-ray observations have provided information about the maximum energy to which these shOCks accelerate electrons, as well as indirect evidence of proton acceleration. Shock morphologies measured in X-rays have indicated that a substantial fraction of the shock energy can be diverted into particle acceleration. This presentation will summarize what we have learned about cosmic ray acceleration from X-ray observations of supernova remnants over the past two decades.

  4. Apollo-Soyuz pamphlet no. 6: Cosmic ray dosage. [experimental designiradiation hazards and dosage

    NASA Technical Reports Server (NTRS)

    Page, L. W.; From, T. P.

    1977-01-01

    The radiation hazard inside spacecraft is discussed with emphasis on its effects on the crew, biological specimens, and spacecraft instruments. The problem of light flash sensations in the eyes of astronauts is addressed and experiment MA-106 is described. In this experiment, light flashes seen by blindfolded astronauts were counted and high energy cosmic ray intensity in the command module cabin were measured. The damage caused by cosmic ray hits on small living organisms was investigated in the Biostack 3 experiment (MA-107). Individual cosmic rays were tracked through layers of bacterial spores, small seeds, and eggs interleaved with layers of AgCl-crystal wafers, special plastic, and special photographic film that registered each cosmic ray particle passed.

  5. Quantification of seasonal biomass effects on cosmic-ray soil water content determination

    NASA Astrophysics Data System (ADS)

    Baatz, Roland; Bogena, Heye; Hendriks-Franssen, Harrie-Jan; Huisman, Johan Alexander; Montzka, Carsten; Vereecken, Harry

    2014-05-01

    Cosmic-ray soil moisture probes (CRS) utilize the fact that high-energy cosmic-ray neutrons are moderated (slowed to lower energies) as they most effective collide with terrestrial hydrogen atoms contained in water molecules. Low-energy cosmic-ray neutron intensity near the ground is therefore a measure of the water content of nearby soils and any water on the ground. In this study we present calibration results of a cosmic-ray soil moisture network in the Rur catchment, Germany. We propose a method to correct for above ground biomass vegetation effects on neutron flux density to improve soil water content estimates from cosmic-ray measurements. The correction for above ground water equivalents aims to remove biases in soil water content measurements on sites with high seasonal vegetation dynamics such as agricultural fields. Above ground biomass is estimated as function of the normalized difference vegetation index using regression equations. The regression equations were obtained from literature information, ground-based control measurements, a crop growth model and globally available data from the Moderate Resolution Imaging Spectrometer (MODIS). The results show that above ground biomass could be well estimated during the first half of the year. Seasonal changes in vegetation water content yielded biases in soil water content of ~0.05 cm³/cm³ that could be corrected for with the vegetation correction. The vegetation correction has particularly high potential when applied at long term cosmic-ray monitoring sites and the cosmic-ray rover.

  6. Near-field effects of Cherenkov radiation induced by ultra high energy cosmic neutrinos

    NASA Astrophysics Data System (ADS)

    Hu, Chia-Yu; Chen, Chih-Ching; Chen, Pisin

    2012-02-01

    The radio approach based on the Askaryan effect for detecting the ultra-high energy cosmic neutrinos has become a mature experimental technique. So far the existing calculations of the Cherenkov radiation associated with the Askaryan effect has been mostly based on the far-field approximation, whose validity maybe challenged when the detector is close to the event. In this paper we present an alternative approach to calculate the Cherenkov pulse by a numerical code based on the finite difference time-domain (FDTD) method. This approach has the advantage of providing the solution everywhere in space, contrary to other methods that rely on the far-field approximation. We also present a one-dimensional theoretical model for the shower with analytical solution, which helps to elucidate our nonzero-width simulation results. We show that for a shower with symmetric longitudinal development, the resulting near-field waveform would be asymmetric in time. In addition, we demonstrate that for a shower elongated by the LPM (Landau-Pomeranchuk-Migdal) effect and thus with a multi-peak structure, a bipolar, asymmetric waveform is still preserved in the near-field regime irrespective of the specific variations of the multi-peak structure, which makes it a generic, distinctive feature. This should provide an important characteristic signature for the identification of ultra-high energy cosmogenic neutrinos.

  7. A BAYESIAN APPROACH TO COMPARING COSMIC RAY ENERGY SPECTRA

    SciTech Connect

    BenZvi, S. Y.; Pfendner, C. G.; Westerhoff, S. [Department of Physics, University of Wisconsin-Madison, Madison, WI 53706 (United States); Connolly, B. M. [Department of Physics, University of Pennsylvania, Philadelphia, PA 19104 (United States)

    2011-09-01

    A common problem in ultra-high energy cosmic ray physics is the comparison of energy spectra. The question is whether the spectra from two experiments or two regions of the sky agree within their statistical and systematic uncertainties. We develop a method to directly compare energy spectra for ultra-high energy cosmic rays from two different regions of the sky in the same experiment without reliance on agreement with a theoretical model of the energy spectra. The consistency between the two spectra is expressed in terms of a Bayes factor, defined here as the ratio of the likelihood of the two-parent source hypothesis to the likelihood of the one-parent source hypothesis. Unlike other methods, for example {chi}{sup 2} tests, the Bayes factor allows for the calculation of the posterior odds ratio and correctly accounts for non-Gaussian uncertainties. The latter is particularly important at the highest energies, where the number of events is very small.

  8. Microphysics of Cosmic Ray Driven Plasma Instabilities

    NASA Astrophysics Data System (ADS)

    Bykov, A. M.; Brandenburg, A.; Malkov, M. A.; Osipov, S. M.

    2013-10-01

    Energetic nonthermal particles (cosmic rays, CRs) are accelerated in supernova remnants, relativistic jets and other astrophysical objects. The CR energy density is typically comparable with that of the thermal components and magnetic fields. In this review we discuss mechanisms of magnetic field amplification due to instabilities induced by CRs. We derive CR kinetic and magnetohydrodynamic equations that govern cosmic plasma systems comprising the thermal background plasma, comic rays and fluctuating magnetic fields to study CR-driven instabilities. Both resonant and non-resonant instabilities are reviewed, including the Bell short-wavelength instability, and the firehose instability. Special attention is paid to the longwavelength instabilities driven by the CR current and pressure gradient. The helicity production by the CR current-driven instabilities is discussed in connection with the dynamo mechanisms of cosmic magnetic field amplification.

  9. Microphysics of Cosmic Ray Driven Plasma Instabilities

    NASA Astrophysics Data System (ADS)

    Bykov, A. M.; Brandenburg, A.; Malkov, M. A.; Osipov, S. M.

    Energetic nonthermal particles (cosmic rays, CRs) are accelerated in supernova remnants, relativistic jets and other astrophysical objects. The CR energy density is typically comparable with that of the thermal components and magnetic fields. In this review we discuss mechanisms of magnetic field amplification due to instabilities induced by CRs. We derive CR kinetic and magnetohydrodynamic equations that govern cosmic plasma systems comprising the thermal background plasma, comic rays and fluctuating magnetic fields to study CR-driven instabilities. Both resonant and non-resonant instabilities are reviewed, including the Bell short-wavelength instability, and the firehose instability. Special attention is paid to the longwavelength instabilities driven by the CR current and pressure gradient. The helicity production by the CR current-driven instabilities is discussed in connection with the dynamo mechanisms of cosmic magnetic field amplification.

  10. Primary cosmic-ray energy spectrum around the knee energy region measured by the Tibet hybrid

    E-print Network

    Primary cosmic-ray energy spectrum around the knee energy region measured by the Tibet hybrid-8561, Japan 2 Department of Physics, Saitama University, Saitama 338-8570, Japan 3 Institute of High Energy for Informatics, Tokyo 101-8430, Japan 18 Tokyo Metropolitan College of Aeronautical Engineering, Tokyo 116

  11. Astrophysical Sources of Cosmic Rays and Related Measurements with the Pierre Auger Observatory

    Microsoft Academic Search

    P. Abreu; M. Aglietta; C. Aguirre; E. J. Ahn; D. Allard; I. Allekotte; J. Allen; J. Alvarez-Muñiz; M. Ambrosio; L. Anchordoqui; S. Andringa; A. Anzalone; C. Aramo; E. Arganda; S. Argirò; K. Arisaka; F. Arneodo; F. Arqueros; T. Asch; H. Asorey; P. Assis; J. Aublin; G. Avila; T. Bäcker; D. Badagnani; K. B. Barber; A. F. Barbosa; S. L. C. Barroso; B. Baughman; P. Bauleo; J. J. Beatty; T. Beau; B. R. Becker; K. H. Becker; A. Bellétoile; S. BenZvi; C. Berat; P. Bernardini; X. Bertou; P. L. Biermann; O. Blanch-Bigas; F. Blanco; C. Bleve; H. Blümer; M. Bohácová; D. Boncioli; C. Bonifazi; R. Bonino; N. Borodai; J. Brack; P. Brogueira; W. C. Brown; R. Bruijn; P. Buchholz; A. Bueno; R. E. Burton; N. G. Busca; K. S. Caballero-Mora; L. Caramete; R. Caruso; W. Carvalho; A. Castellina; O. Catalano; L. Cazon; R. Cester; J. Chauvin; A. Chiavassa; J. A. Chinellato; A. Chou; J. Chudoba; R. W. Clay; E. Colombo; R. Conceição; B. Connolly; F. Contreras; J. Coppens; A. Cordier; U. Cotti; S. Coutu; C. E. Covault; A. Creusot; J. Cronin; A. Curutiu; S. Dagoret-Campagne; R. Dallier; K. Daumiller; B. R. Dawson; R. M. de Almeida; C. De Donato; S. J. de Jong; G. De La Vega; W. J. M. de Mello Junior; I. De Mitri; V. de Souza; K. D. de Vries; G. Decerprit; L. del Peral; O. Deligny; A. Della Selva; C. Delle Fratte; H. Dembinski; C. DiGiulio; P. N. Diep; C. Dobrigkeit; P. N. Dong; A. Dorofeev; J. C. dos Anjos; M. T. Dova; D. D'Urso; I. Dutan; M. A. DuVernois; R. Engel; M. Erdmann; C. O. Escobar; A. Etchegoyen; P. Facal San Luis; H. Falcke; G. Farrar; A. C. Fauth; N. Fazzini; F. Ferrer; A. Ferrero; B. Fick; A. Filevich; A. Filipcic; I. Fleck; S. Fliescher; C. E. Fracchiolla; E. D. Fraenkel; W. Fulgione; R. F. Gamarra; S. Gambetta; B. García; D. GarcíaGámez; D. Garcia-Pinto; X. Garrido; G. Gelmini; H. Gemmeke; P. L. Ghia; U. Giaccari; M. Giller; H. Glass; L. M. Goggin; M. S. Gold; G. Golup; F. Gomez Albarracin; M. Gómez Berisso; P. Gonçalves; M. Gonçalves do Amaral; D. Gonzalez; J. G. Gonzalez; D. Góra; A. Gorgi; P. Gouffon; S. R. Gozzini; E. Grashorn; S. Grebe; M. Grigat; A. F. Grillo; Y. Guardincerri; F. Guarino; G. P. Guedes; J. Gutiérrez; J. D. Hague; V. Halenka; P. Hansen; D. Harari; S. Harmsma; J. L. Harton; A. Haungs; M. D. Healy; T. Hebbeker; G. Hebrero; D. Heck; V. C. Holmes; P. Homola; J. R. Hörandel; A. Horneffer; M. Hrabovský; T. Huege; M. Hussain; M. Iarlori; A. Insolia; F. Ionita; A. Italiano; S. Jiraskova; M. Kaducak; K. H. Kampert; T. Karova; P. Kasper; B. Kégl; B. Keilhauer; E. Kemp; R. M. Kieckhafer; H. O. Klages; M. Kleifges; J. Kleinfeller; R. Knapik; J. Knapp; D.-H. Koang; A. Krieger; O. Krömer; D. Kruppke-Hansen; F. Kuehn; D. Kuempel; K. Kulbartz; N. Kunka; A. Kusenko; G. LaRosa; C. Lachaud; B. L. Lago; P. Lautridou; M. S. A. B. Leão; D. Lebrun; P. Lebrun; J. Lee; M. A. Leigui de Oliveira; A. Lemiere; A. Letessier-Selvon; M. Leuthold; I. Lhenry-Yvon; R. López; A. Lopez Agüera; K. Louedec; J. Lozano Bahilo; A. Lucero; H. Lyberis; M. C. Maccarone; C. Macolino; S. Maldera; D. Mandat; P. Mantsch; A. G. Mariazzi; I. C. Maris; H. R. Marquez Falcon; D. Martello; O. Martínez Bravo; H. J. Mathes; J. Matthews; G. Matthiae; D. Maurizio; P. O. Mazur; M. McEwen; R. R. McNeil; G. Medina-Tanco; M. Melissas; D. Melo; E. Menichetti; A. Menshikov; R. Meyhandan; M. I. Micheletti; G. Miele; W. Miller; L. Miramonti; S. Mollerach; M. Monasor; D. Monnier Ragaigne; F. Montanet; B. Morales; C. Morello; J. C. Moreno; C. Morris; M. Mostafá; C. A. Moura; S. Mueller; M. A. Muller; R. Mussa; G. Navarra; J. L. Navarro; S. Navas; P. Necesal; L. Nellen; C. Newman-Holmes; D. Newton; P. T. Nhung; N. Nierstenhoefer; D. Nitz; D. Nosek; L. Nozka; M. Nyklicek; J. Oehlschläger; A. Olinto; P. Oliva; V. M. Olmos-Gilbaja; M. Ortiz; N. Pacheco; D. Pakk Selmi-Dei; M. Palatka; J. Pallotta; G. Parente; E. Parizot; S. Parlati; S. Pastor; M. Patel; T. Paul; V. Pavlidou; K. Payet; M. Pech; J. Pekala; I. M. Pepe; L. Perrone; R. Pesce; E. Petermann; S. Petrera; P. Petrinca; A. Petrolini; Y. Petrov; J. Petrovic; C. Pfendner; R. Piegaia; T. Pierog; M. Pimenta; T. Pinto; V. Pirronello; O. Pisanti; M. Platino; J. Pochon; V. H. Ponce; M. Pontz; P. Privitera; M. Prouza; E. J. Quel; J. Rautenberg; O. Ravel; D. Ravignani; A. Redondo; B. Revenu; F. A. S. Rezende; J. Ridky; S. Riggi; M. Risse; C. Rivière; V. Rizi; C. Robledo; G. Rodriguez; J. Rodriguez Martino; J. Rodriguez Rojo; I. Rodriguez-Cabo; M. D. Rodríguez-Frías; G. Ros; J. Rosado; T. Rossler; M. Roth; B. Rouillé-d'Orfeuil; E. Roulet; A. C. Rovero; F. Salamida; H. Salazar; G. Salina; F. Sánchez; M. Santander; C. E. Santo; E. M. Santos; F. Sarazin; S. Sarkar; R. Sato; N. Scharf; V. Scherini; H. Schieler; P. Schiffer; A. Schmidt; F. Schmidt; T. Schmidt; O. Scholten; H. Schoorlemmer; J. Schovancova; P. Schovánek; F. Schroeder

    2009-01-01

    Studies of the correlations of ultra-high energy cosmic ray directions with extra-Galactic objects, of general anisotropy, of photons and neutrinos, and of other astrophysical effects, with the Pierre Auger Observatory. Contributions to the 31st ICRC, Lodz, Poland, July 2009.

  12. Particle acceleration at astrophysical shocks: A theory of cosmic ray origin

    Microsoft Academic Search

    Roger Blandford; David Eichler

    1987-01-01

    The theory of first order Fermi acceleration at collisionless astrophysical shock fronts is reviewed. Observations suggest that shock waves in different astrophysical environments accelerate cosmic rays efficiently. In the first order process, high energy particles diffuse through Alfvén waves that scatter them and couple them to the background plasma. These particles gain energy, on the average, every time they cross

  13. 30TH INTERNATIONAL COSMIC RAY CONFERENCE A Linear Accelerator for TA-FD calibration

    E-print Network

    to calibrate between number of photons and energy directly. In the Telescope Array project, we proposed The Telescope Array project(TA) is one of the large scale experiment which observes extremely high energy cosmic ray. It consists of Fluores- cence Detectors(FD) and Surface Detectors(SD). FD observes ultraviolet

  14. Are Clusters as Indicators of the Cosmic Ray Anisotropy ?

    E-print Network

    A. A. Mikhailov; N. N. Efremov

    2004-11-01

    The clusters (doublets) in ultrahigh energy cosmic rays are considered based on Yakutsk and AGASA extensive air shower array data. The problem of cluster origin is discussed. It is found that arrival directions of the clusters can point to a cosmic ray anisotropy. As a result of analysis of clusters, the conclusion on composition and origin of ultrahigh energy cosmic rays has been made.

  15. EGRET - The high energy gamma ray telescope for NASA's Gamma Ray Observatory

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.; Bertsch, D. L.; Hartman, R. C.; Kniffen, D. A.; Thompson, D. J.; Hofstadter, R.; Hughes, E. B.; Campbell-Finman, L. E.; Pinkau, K.; Mayer-Hasselwander, H.

    1983-01-01

    The EGRET high energy gamma-ray telescope under development for NASA's Gamma Ray Observatory will have an energy range of approximately 12 to 30,000 MeV, energy resolution of about 15 percent FWHM over most of that range, an effective area of about 2000 sq cm at high energies, and single photon angular accuracy of approximately 2 deg at 100 MeV, less than 0.1 deg above 5 GeV. This instrument can locate strong sources to an accuracy of about 5 arc min. The instrument utilizes a set of digital spark chambers interleaved with tantalum foils for detection and identification of gamma-ray events, and a large NaI(Tl) scintillator for energy determination. The system is triggered by a coincidence matrix using two arrays of plastic scintillation counters and a large plastic scintillator anticoincidence dome that rejects incident charged particles.

  16. Gamma-ray astronomy and the origin of cosmic rays

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.

    1978-01-01

    New surveys of galactic gamma ray emission together with millimeter wave radio surveys indicated that cosmic rays were produced as the result of supernova explosions in our galaxy with the most intense production occurring in a Great Galactic Ring about 35,000 light years in diameter where supernova remnants and pulsars were concentrated.

  17. Gamma-Ray Emission of Supernova Remnants and the Origin of Galactic Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Aharonian, F. A.

    The recent surveys of the Milky Way with space and ground-based gamma-ray detectors revealed hundreds of high energy (HE) and tens of very high energy (VHE) gamma-ray emitters representing several galactic source populations - supernova remnants, giant molecular clouds, star forming regions, pulsars, pulsar wind nebulae, binary systems. The major fraction of these objects remains however unidentified. In this chapter I discuss the astrophysical implications of VHE gamma-ray observations of supernova remnants (SNRs) in the context of the origin of galactic cosmic rays. These observations confirm the earlier theoretical predictions of effective acceleration of multi-TeV particles in young SNRs by strong shock waves. The interpretation of VHE gamma-ray data from several prominent representatives of young SNRs within the so-called hadronic models requires hard energy spectra of protons extending to 100 TeV, with total energy released in relativistic protons and nuclei as large as 1050 erg. Formally, this can be considered as an observational proof of the so-called SNR paradigm of the origin of galactic cosmic rays. However, the hadronic models are not free of problems related to interpretation of multi-wavelength properties of these objects. Moreover, in most of the cases the gamma-ray data can be explained by the inverse Compton scattering of electrons which are responsible also for the synchrotron X-radiation of young SNRs. These circumstances prevent us from a firm statement about the contribution of SNRs to the overall flux of galactic cosmic rays. Further observations of young SNRs, especially in the highest energy band (well above 10 TeV), can be crucial in this regard. Quite important are also the complementary observations from massive molecular clouds located within the close proximity of mid-age SNRs.

  18. Mapping the most energetic cosmic rays

    Microsoft Academic Search

    A. M. Hillas

    2009-01-01

    The Pierre Auger Collaboration has shown that the cosmic rays detected to August 2007, with estimated energies above 57 EeV, were mostly very close to the direction of a catalogued AGN within ˜75Mpc. The closeness of the sources to us, and their association with the locality of moderate Seyfert galaxies rather than the most striking radio galaxies, were surprising, leading

  19. Mapping the most energetic cosmic rays

    Microsoft Academic Search

    A. M. Hillas

    2009-01-01

    The Pierre Auger Collaboration has shown that the cosmic rays detected to August 2007, with estimated energies above 57EeV, were mostly very close to the direction of a catalogued AGN within ?75Mpc. The closeness of the sources to us, and their association with the locality of moderate Seyfert galaxies rather than the most striking radio galaxies, were surprising, leading some

  20. Numerical likelihood analysis of cosmic ray anisotropies

    SciTech Connect

    Carlos Hojvat et al.

    2003-07-02

    A numerical likelihood approach to the determination of cosmic ray anisotropies is presented which offers many advantages over other approaches. It allows a wide range of statistically meaningful hypotheses to be compared even when full sky coverage is unavailable, can be readily extended in order to include measurement errors, and makes maximum unbiased use of all available information.

  1. Radiation from Cosmic Ray Air Showers

    Microsoft Academic Search

    F. D. Kahn; I. Lerche

    1966-01-01

    Cosmic ray showers passing through the atmosphere produce electromagnetic disturbances. It has been suggested that these can be detected by means of a radio telescope. We set up a simple model for a shower and find that the time-integrated energy flux in its radiation field, at say 45 Mc\\/s, is of the order of 60 000 flux units x microseconds,

  2. Believability of signals from cosmic ray sources

    SciTech Connect

    Goodman, M.

    1990-11-01

    This paper discusses some of the criteria by which an observer judges whether to believe a signal or limit that has been reported for a cosmic ray source. The importance of specifying the test before looking at the data is emphasized. 5 refs.

  3. The energy spectrum of cosmic ray positrons

    Microsoft Academic Search

    M. Giler; J. Wdowczyk; A. W. Wolfendale

    1977-01-01

    A calculation has been made of the predicted energy spectrum of positrons generated by the positive pions and kaons produced in turn in the interactions of cosmic ray nuclei with the interstellar medium (ISM). A critical appraisal of the results and a comparison with the predictions of other workers are given. Experimental data on the measured energy spectrum have been

  4. A Cosmic-Ray Radio Sonde

    Microsoft Academic Search

    H. V. Neher; W. H. Pickering

    1942-01-01

    The cosmic-ray radio sonde described in this paper was used for observations in the stratosphere near the magnetic equator. The instrument can be used for single counters or coincidences up to fourfold. It includes the necessary amplifiers and scaling circuits to operate a relay which keys the radio-transmitter. High voltage for the counters is provided by a buzzer and transformer

  5. Searching for Dark Matter with Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Seo, Eun-Suk

    2015-04-01

    One of the most exciting possibilities in cosmic ray research is the potential to discover new phenomena. A number of elementary particles were discovered in cosmic rays before modern-day accelerators became available to study their detailed properties. Since the discovery of cosmic ray antiprotons in 1979 using a balloon-borne magnet spectrometer, a series of magnet spectrometers have been flown to search for the signature of dark matter annihilation in antiprotons and positrons. Being the same as particles except for their opposite charge sign, antiparticles are readily distinguished as they bend in opposite directions in the magnetic field. As long-duration balloon flights over Antarctica became available, not only antiproton to proton ratios but also measurements of antiproton energy spectra became possible. More recently, space missions are also providing precision measurements of electron and position energy spectra. With other measurements to constrain cosmic ray propagation models, these new measurements play key roles in constraining dark-matter models for understanding the nature of dark matter. Recent results, their implications, and outlook for the field will be presented.

  6. Cosmic Ray Acceleration by Magnetic Traps

    E-print Network

    V. N. Zirakashvili

    2001-06-05

    Cosmic ray acceleration in turbulent interstellar medium is considered. Turbulence is treated as ensemble of moving magnetic traps. We derive equations for particle momentum distribution function that describes acceleration of particles in this case. Rate of acceleration calculated is estimated for our Galaxy and compared with ones given by other acceleration mechanisms.

  7. Cosmic-ray ionisation in collapsing clouds

    NASA Astrophysics Data System (ADS)

    Padovani, M.; Hennebelle, P.; Galli, D.

    2013-12-01

    Context. Cosmic rays play an important role in dense molecular cores, affecting their thermal and dynamical evolution and initiating the chemistry. Several studies have shown that the formation of protostellar discs in collapsing clouds is severely hampered by the braking torque exerted by the entrained magnetic field on the infalling gas, as long as the field remains frozen to the gas. Aims: In this paper we examine the possibility that the concentration and twisting of the field lines in the inner region of collapse can produce a significant reduction of the ionisation fraction. Methods: To check whether the cosmic-ray ionisation rate can fall below the critical value required to maintain good coupling, we first study the propagation of cosmic rays in a model of a static magnetised cloud varying the relative strength of the toroidal/poloidal components and the mass-to-flux ratio. We then follow the path of cosmic rays using realistic magnetic field configurations generated by numerical simulations of a rotating collapsing core with different initial conditions. Results: We find that an increment of the toroidal component of the magnetic field, or, in general, a more twisted configuration of the field lines, results in a decrease in the cosmic-ray flux. This is mainly due to the magnetic mirroring effect that is stronger where larger variations in the field direction are present. In particular, we find a decrease of the cosmic-ray ionisation rate below 10-18 s-1 in the central 300-400 AU, where density is higher than about 109 cm-3. This very low value of the ionisation rate is attained in the cases of intermediate and low magnetisation (mass-to-flux ratio ? = 5 and 17, respectively) and for toroidal fields larger than about 40% of the total field. Conclusions: Magnetic field effects can significantly reduce the ionisation fraction in collapsing clouds. We provide a handy fitting formula to compute approximately the attenuation of the cosmic-ray ionisation rate in a molecular cloud as a function of the density and the magnetic configuration.

  8. DISCOVERY OF HIGH-ENERGY AND VERY HIGH ENERGY {gamma}-RAY EMISSION FROM THE BLAZAR RBS 0413

    SciTech Connect

    Aliu, E. [Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027 (United States); Archambault, S. [Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada); Arlen, T. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Aune, T.; Bouvier, A. [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 (United States); Beilicke, M.; Buckley, J. H.; Bugaev, V. [Department of Physics, Washington University, St. Louis, MO 63130 (United States); Benbow, W. [Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States); Boettcher, M. [Astrophysical Institute, Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); Bradbury, S. M. [School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT (United Kingdom); Byrum, K.; Decerprit, G. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Cannon, A.; Collins-Hughes, E. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Cesarini, A.; Connolly, M. P. [School of Physics, National University of Ireland Galway, University Road, Galway (Ireland); Ciupik, L. [Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States); Coppi, P. [Department of Astronomy, Yale University, P. O. Box 208101 New Haven, CT 06511 (United States); Cui, W., E-mail: gunessenturk@gmail.com, E-mail: fortin@llr.in2p3.fr, E-mail: deirdre@llr.in2p3.fr [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); and others

    2012-05-10

    We report on the discovery of high-energy (HE; E > 0.1 GeV) and very high energy (VHE; E > 100 GeV) {gamma}-ray emission from the high-frequency-peaked BL Lac object RBS 0413. VERITAS, a ground-based {gamma}-ray observatory, detected VHE {gamma} rays from RBS 0413 with a statistical significance of 5.5 standard deviations ({sigma}) and a {gamma}-ray flux of (1.5 {+-} 0.6{sub stat} {+-} 0.7{sub syst}) Multiplication-Sign 10{sup -8} photons m{sup -2} s{sup -1} ({approx}1% of the Crab Nebula flux) above 250 GeV. The observed spectrum can be described by a power law with a photon index of 3.18 {+-} 0.68{sub stat} {+-} 0.30{sub syst}. Contemporaneous observations with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope detected HE {gamma} rays from RBS 0413 with a statistical significance of more than 9{sigma}, a power-law photon index of 1.57 {+-} 0.12{sub stat}+{sup 0.11}{sub -0.12sys}, and a {gamma}-ray flux between 300 MeV and 300 GeV of (1.64 {+-} 0.43{sub stat}{sup +0.31}{sub -0.22sys}) Multiplication-Sign 10{sup -5} photons m{sup -2} s{sup -1}. We present the results from Fermi-LAT and VERITAS, including a spectral energy distribution modeling of the {gamma}-ray, quasi-simultaneous X-ray (Swift-XRT), ultraviolet (Swift-UVOT), and R-band optical (MDM) data. We find that, if conditions close to equipartition are required, both the combined synchrotron self-Compton/external-Compton and the lepto-hadronic models are preferred over a pure synchrotron self-Compton model.

  9. In Search of Cosmic Rays: A Student Physics Project Aimed at Finding the Origin of Cosmic Rays.

    ERIC Educational Resources Information Center

    Antonelli, Jamie; Mahoney, Sean; Streich, Derek; Liebl, Michael

    2001-01-01

    Describes an ongoing project, the Cosmic Ray Observatory Project (CROP), being conducted by the University of Nebraska in partnership with several high schools. Each school group has installed cosmic ray detectors, and initial activities have included calibrating equipment, gathering preliminary data, and learning about cosmic ray showers. Aims to…

  10. Supernova Remnants as the Sources of Galactic Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Vink, J.

    2013-01-01

    The origin of cosmic rays holds still many mysteries hundred years after they were first discovered. Supernova remnants have for long been the most likely sources of Galactic cosmic rays. I discuss here some recent evidence that suggests that supernova remnants can indeed efficiently accelerate cosmic rays. For this conference devoted to the Astronomical Institute Utrecht I put the emphasis on work that was done in my group, but placed in a broader context: efficient cosmic-ray acceleration and the implications for cosmic-ray escape, synchrotron radiation and the evidence for magnetic-field amplification, potential X-ray synchrotron emission from cosmic-ray precursors, and I conclude with the implications of cosmic-ray escape for a Type Ia remnant like Tycho and a core-collapse remnant like Cas A.

  11. 10Be Production in the Atmosphere by Galactic Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Matthiä, Daniel; Herbst, Klaudia; Heber, Bernd; Berger, Thomas; Reitz, Günther

    2013-06-01

    Galactic cosmic ray nuclei and energetic protons produced in solar flares and accelerated by coronal mass ejections are the main sources of high-energy particles of extraterrestrial origin in near-Earth space and inside the Earth's atmosphere. The intensity of galactic cosmic rays inside the heliosphere is strongly influenced by the modulation of the interstellar source particles on their way through interplanetary space. Among others, this modulation depends on the activity of the Sun, and the resulting intensity of the energetic particles in the atmosphere is an indicator of the solar activity. Therefore, rare isotopes found in historical archives and produced by spallation reactions of primary and secondary hadrons of cosmic origin in the atmosphere, so-called cosmogenic nuclides, can be used to reconstruct the solar activity in the past. The production rate of 10Be, one of the cosmogenic nuclides most adequate to study the solar activity, is presented showing its variations with geographic latitude and altitude and the dependence on different production cross-sections present in literature. In addition, estimates for altitude integrated production rates of 10Be at different locations since the early nineteen sixties are shown.

  12. Small-Scale Anisotropy of Cosmic Rays above 10^19 eV Observed with the Akeno Giant Air Shower Array

    Microsoft Academic Search

    M. Takeda; N. Hayashida; K. Honda; N. Inoue; K. Kadota; F. Kakimoto; K. Kamata; S. Kawaguchi; Y. Kawasaki; N. Kawasumi; E. Kusano; Y. Matsubara; K. Murakami; M. Nagano; D. Nishikawa; H. Ohoka; S. Osone; N. Sakaki; M. Sasaki; K. Shinozaki; N. Souma; M. Teshima; R. Torii; I. Tsushima; Y. Uchihori; T. Yamamoto; S. Yoshida; H. Yoshii

    1999-01-01

    With the Akeno Giant Air Shower Array, 581 cosmic rays above 10^19 eV, 47 above 4x10^19 eV, and seven above 10^20 eV were observed until 1998 August. The arrival direction distribution of these extremely high energy cosmic rays has been studied. While no significant large-scale anisotropy is found on the celestial sphere, some interesting clusters of cosmic rays are observed.

  13. Development of a two-fold segmented detection system for near horizontally cosmic-ray muons to probe the internal structure of a volcano

    Microsoft Academic Search

    H. Tanaka; K. Nagamine; N. Kawamura; S. N. Nakamura; K. Ishida; K. Shimomura

    2003-01-01

    Very high-energy cosmic-ray muons penetrating through a mountain enable us to probe internal structure of volcanoes. An improved cosmic-ray muon detection system comprising two segmented detectors with multiplicity cut of the soft-component background of cosmic ray was developed. By applying to the measurement on internal structure of the volcano Mt. Asama, we proved that the volume occupancy in the region

  14. Results from high-energy neutrino searches from gamma-ray bursts with IceCube

    NASA Astrophysics Data System (ADS)

    Whitehorn, N.; IceCube Collaboration

    2012-07-01

    IceCube, a cubic kilometer neutrino detector located in glacial ice at the South Pole, has recently become the first neutrino telescope with a sensitivity below the TeV-PeV neutrino flux predicted from gamma-ray bursts if GRBs are responsible for the observed extragalactic cosmic-ray flux. IceCube has so far not detected any evidence for the predicted neutrino fluxes, and so is beginning to constrain models of cosmic ray acceleration in GRBs.

  15. Constraints on Very High Energy gamma-ray emission from Gamma-Ray Bursts

    E-print Network

    R. Atkins; W. Benbow; D. Berley; E. Blaufuss; D. G. Coyne; T. DeYoung; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; L. Fleysher; R. Fleysher; M. M. Gonzalez; J. A. Goodman; E. Hays; C. M. Hoffman; L. A. Kelley; C. P. Lansdell; J. T. Linnemann; J. E. McEnery; A. I. Mincer; M. F. Morales; P. Nemethy; D. Noyes; J. M. Ryan; F. W. Samuelson; P. M. Saz Parkinson; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; D. A. Williams; M. E. Wilson; X. W. Xu; G. B. Yodh

    2005-03-11

    The Milagro gamma-ray observatory employs a water Cherenkov detector to observe extensive air showers produced by high energy particles interacting in the Earth's atmosphere. Milagro has a wide field of view and high duty cycle, monitoring the northern sky almost continuously in the 100 GeV to 100 TeV energy range. Milagro is, thus, uniquely capable of searching for very high-energy emission from gamma-ray bursts (GRBs) during the prompt emission phase. Detection of >100 GeV counterparts would place powerful constraints on GRB mechanisms. Twenty-five satellite-triggered GRBs occurred within the field of view of Milagro between January 2000 and December 2001. We have searched for counterparts to these GRBs and found no significant emission from any of the burst positions. Due to the absorption of high-energy gamma rays by the extragalactic background light, detections are only expected to be possible for redshifts less than ~0.5. Three of the GRBs studied have measured redshifts. GRB 010921 has a redshift low enough (0.45) to allow an upper limit on the fluence to place an observational constraint on potential GRB models.

  16. Status of Radio and Acoustic Detection of Ultra-High Energy Cosmic Neutrinos and a Proposal on Reporting Results

    NASA Astrophysics Data System (ADS)

    Saltzberg, David

    2005-01-01

    Neutrino astronomy offers the possibility to perform extra-galactic observations well beyond the photon absorption cutoff above 5 × 1013 eV. Based on observations of cosmic rays, we already know that astrophysical sources produce particles with at least a million times more energy than this photon cutoff. Once discovered, either the nature of the sources themselves or the cross sections of ultra-high energy neutrinos with terrestrial matter may reveal exotic physical processes that are inaccessible to modern accelerators. Some of these processes may be due to as-yet unknown physics at the grand unification scale or beyond. Neutrino telescopes based on optical techniques currently operating and under construction have apertures measured in several km3-sr. Radio and acoustic detection techniques have been demonstrated in laboratory experiments and are currently used for instrumentation of apertures 10 to 10,000 times larger than optical techniques for neutrinos above 1016 eV. I discuss the status of current and proposed neutrino telescope projects based on these techniques. These telescopes have already ruled out some of the more exotic predictions for neutrino intensity. The upcoming generation of radio-based and acoustic-based detectors should be sensitive to cosmic neutrinos above 1018 eV originating through the so-called GZK process. A comparison of different neutrino telescopes using a common aperture variable shows how they are complementary in the trade-offs of volume versus threshold. I include a proposal for how neutrino telescopes should report their sensitivities to facilitate direct comparisons among them and to allow testing of neutrino brightness models that appear even after publication of the experimental results.

  17. Status of Radio and Acoustic Detection of Ultra-High Energy Cosmic Neutrinos and a Proposal on Reporting Results

    NASA Astrophysics Data System (ADS)

    Saltzberg, David

    2006-03-01

    Neutrino astronomy offers the possibility to perform extra-galactic observations well beyond the photon absorption cutoff above 5 × 1013 eV. Based on observations of cosmic rays, we already know that astrophysical sources produce particles with at least a million times more energy than this photon cutoff. Once discovered, either the nature of the sources themselves or the cross sections of ultra-high energy neutrinos with terrestrial matter may reveal exotic physical processes that are inaccessible to modern accelerators. Some of these processes may be due to as-yet unknown physics at the grand unification scale or beyond. Neutrino telescopes based on optical techniques currently operating and under construction have apertures measured in several km3-sr. Radio and acoustic detection techniques have been demonstrated in laboratory experiments and are currently used for instrumentation of apertures 10 to 10,000 times larger than optical techniques for neutrinos above 1016 eV. I discuss the status of current and proposed neutrino telescope projects based on these techniques. These telescopes have already ruled out some of the more exotic predictions for neutrino intensity. The upcoming generation of radio-based and acoustic-based detectors should be sensitive to cosmic neutrinos above 1018 eV originating through the so-called GZK process. A comparison of different neutrino telescopes using a common aperture variable shows how they are complementary in the trade-offs of volume versus threshold. I include a proposal for how neutrino telescopes should report their sensitivities to facilitate direct comparisons among them and to allow testing of neutrino brightness models that appear even after publication of the experimental results.

  18. Photon damping in cosmic-ray acceleration in active galactic nuclei

    SciTech Connect

    Colgate, S.A.

    1983-04-07

    The usual assumption of the acceleration of ultra high energy cosmic rays, greater than or equal to 10/sup 18/ eV in quasars, Seyfert galaxies and other active galactic nuclei is challenged on the basis of the photon interactions with the accelerated nucleons. This is similar to the effect of the black body radiation on particles > 10/sup 20/ eV for times of the age of the universe except that the photon spectrum is harder and the energy density greater by approx. = 10/sup 15/. Hence, a single traversal, radial or circumferential, of radiation whose energy density is no greater than the emitted flux will damp an ultra high energy. Hence, it is unlikely that any reasonable configuration of acceleration can void disastrous photon energy loss. A different site for ultra high energy cosmic ray acceleration must be found.

  19. Astrophysical Sources of Cosmic Rays and Related Measurements with the Pierre Auger Observatory

    SciTech Connect

    Abraham, : J.; Abreu, P.; Aglietta, M.; Aguirre, C.; Ahn, E.J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.

    2009-06-01

    These are presentations to be presented at the 31st International Cosmic Ray Conference, in Lodz, Poland during July 2009. It consists of the following presentations: (1) Correlation of the highest energy cosmic rays with nearby extragalactic objects in Pierre Auger Observatory data; (2) Discriminating potential astrophysical sources of the highest energy cosmic rays with the Pierre Auger Observatory; (3) Intrinsic anisotropy of the UHECR from the Pierre Auger Observatory; (4) Ultra-high energy photon studies with the Pierre Auger Observatory; (5) Limits on the flux of diffuse ultra high energy neutrinos set using the Pierre Auger Observatory; (6) Search for sidereal modulation of the arrival directions of events recorded at the Pierre Auger Observatory; (7) Cosmic Ray Solar Modulation Studies in the Pierre Auger Observatory; (8) Investigation of the Displacement Angle of the Highest Energy Cosmic Rays Caused by the Galactic Magnetic Field; (9) Search for coincidences with astrophysical transients in Pierre Auger Observatory data; and (10) An alternative method for determining the energy of hybrid events at the Pierre Auger Observatory.

  20. HIGH-ENERGY GAMMA-RAY AFTERGLOWS FROM LOW-LUMINOSITY GAMMA-RAY BURSTS

    SciTech Connect

    He Haoning; Wang Xiangyu; Yu Yunwei [Department of Astronomy, Nanjing University, Nanjing 210093 (China); Meszaros, Peter [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2009-12-01

    The observations of gamma-ray bursts (GRBs) such as 980425, 031203 and 060218, with luminosities much lower than those of other classic bursts, lead to the definition of a new class of GRBs-LL-GRBs. The nature of the outflow responsible for them is not yet clear. Two scenarios have been suggested: one is the conventional relativistic outflow with initial Lorentz factor of order of GAMMA{sub 0} approx> 10 and the other is a trans-relativistic outflow with GAMMA{sub 0} approx = 1-2. Here, we compare the high-energy gamma-ray afterglow emission from these two different models, taking into account both synchrotron self-inverse Compton (SSC) scattering and the external inverse Compton scattering due to photons from the cooling supernova or hypernova envelope (SNIC). We find that the conventional relativistic outflow model predicts a relatively high gamma-ray flux from SSC at early times (<10{sup 4} s for typical parameters) with a rapidly decaying light curve, while in the trans-relativistic outflow model, one would expect a much flatter light curve of high-energy gamma-ray emission at early times, which could be dominated by both the SSC emission and the SNIC emission, depending on the properties of the underlying supernova and the shock parameter epsilon{sub e} and epsilon{sub B}. The Fermi Gamma-ray Space Telescope should be able to distinguish between the two models in the future.

  1. High-energy gamma-rays from GRB X-ray flares

    SciTech Connect

    Wang, X. Y. [Department of Astronomy and Astrophysics, Penn. State University, University Park, PA 16802 (United States); Department of Astronomy, Nanjing University, Nanjing 210093 (China); Li, Z. [Physics Faculty, Weizmann Institute of Science, Rehovot 76100 (Israel); Meszaros, P. [Department of Astronomy and Astrophysics, Penn. State University, University Park, PA 16802 (United States)

    2007-07-12

    The recent detection of X-ray flares during the afterglow phase of gamma-ray bursts (GRBs) suggests an inner-engine origin, at radii inside the forward shock. There must be inverse Compton (IC) emission arising from such flare photons scattered by forward shock afterglow electrons when they are passing through the forward shock. We find that this IC emission produces high energy gamma-ray flares, which may be detected by AGILE, GLAST and ground-based TeV telescopes. The anisotropic IC scattering between flare photons and forward shock electrons does not affect the total IC component intensity, but cause a time delay of the IC component peak relative to the flare peak. We speculate that this IC component may already have been detected by EGRET from a very strong burst--GRB940217. Future observations by GLAST may help to distinguish whether X-ray flares originate from late central engine activity or from external shocks.

  2. Ultrahigh Energy Cosmic Rays: New Physics or Old Physics?

    E-print Network

    F. W. Stecker

    2004-07-15

    We consider the advantages of and the problems associated with hypotheses to explain the origin of ulthrahigh energy cosmic rays (UHECR: E > 10 EeV) and the "trans GZK" cosmic rays (TGZK: E > 100 EeV), both through "old physics" (acceleration in cosmic sources) and "new physics" (new particles, topological defects, fat neutrino cross sections, Lorentz invariance violation).

  3. Precision studies of cosmic rays with PAMELA

    NASA Astrophysics Data System (ADS)

    Pearce, Mark

    The PAMELA satellite-borne apparatus was launched into an elliptical low earth orbit with an inclination of 70 degrees on June 15th 2006. The combination of a permanent magnet silicon strip spectrometer, and a silicon-tungsten imaging calorimeter allows precision studies of the charged cosmic radiation to be conducted over a wide energy range ( 100 MeV - 100's GeV) with high statistics. The primary scientific goal is the measurement of the antiproton and positron energy spectrum in order to search for exotic sources, such as dark matter particle annihilations. PAMELA is also searching for primordial antinuclei (anti-helium), and testing cosmic-ray propagation models through precise measurements of the antiparticle energy spectrum and precision studies of light nuclei and their isotopes. Concomitant goals include a study of solar physics and solar modulation during the 24th solar minimum by investigating low energy particles in the cosmic radiation; and a reconstruction of the cosmic ray electron energy spectrum up to several TeV thereby allowing a possible contribution from local sources to be studied. The status of the PAMELA experiment will be reviewed, and initial scientific results discussed.

  4. Gamma Ray Telescope Senses High-Energy Radiation

    NSDL National Science Digital Library

    WNET

    2011-11-02

    This video from NASA describes the GLAST satellite, which is equipped with a gamma-ray telescope, and shares some background about the kinds of extreme universal phenomena indicated by the presence of gamma rays.

  5. Cosmic rays & Neutrinos Historical development

    E-print Network

    Gaisser, Thomas K.

    | Perm in hairdressing Deutsch The Neutrino Wolfgang Pauli's name is inseparable from his pioneering. The starting point for Pauli was the continuous energy spectrum of beta rays, which could not be interpreted conservation, which Pauli could not accept because the principle of the conservation of energy had proved

  6. Cosmic ray modulation and noise level on the extended multidirectional muons detector telescope installed in south of Brazil: preliminary analysis

    Microsoft Academic Search

    C. R. Braga; J. F. Savian; M. R. da Silva; S. M. da Silva; C. W. da Silva; A. Dal Lago; T. Kuwabara; K. Munakata; J. W. Bieber; N. J. Schuch

    2006-01-01

    Because of the large detector mass required to detect high-energy cosmic rays ground-based instruments remain the state-of-the-art method for studying these particles At energies up to 100 GeV primary galactic cosmic rays experience significant variation in response to solar wind disturbances such as interplanetary coronal mass ejections ICMEs In this way ground-based detectors can provide unique information on conditions in

  7. Nuclear physics of cosmic ray interaction with semiconductor materials: Particle-induced soft errors from a physicist's perspective

    Microsoft Academic Search

    Henry H. K. Tang

    1996-01-01

    The key issues of cosmic-ray-induced soft-error rates, SER (also referred to as single-event upset, SEU, rates) in microelectronic devices are discussed from the viewpoint of fundamental atomic and nuclear interactions between high-energy particles and semiconductors. From sea level to moderate altitudes, the cosmic ray spectrum is dominated by three particle species: nucleons (protons and neutrons), pions, and muons. The characteristic

  8. Cosmic rays, solar activity and the climate

    NASA Astrophysics Data System (ADS)

    Sloan, T.; Wolfendale, A. W.

    2013-12-01

    Although it is generally believed that the increase in the mean global surface temperature since industrialization is caused by the increase in green house gases in the atmosphere, some people cite solar activity, either directly or through its effect on cosmic rays, as an underestimated contributor to such global warming. In this letter a simplified version of the standard picture of the role of greenhouse gases in causing the global warming since industrialization is described. The conditions necessary for this picture to be wholly or partially wrong are then introduced. Evidence is presented from which the contributions of either cosmic rays or solar activity to this warming is deduced. The contribution is shown to be less than 10% of the warming seen in the twentieth century.

  9. Cosmic Rays, Solar Activity and the Climate

    NASA Astrophysics Data System (ADS)

    Sloan, T.

    2013-02-01

    Although it is generally believed that the increase in the mean global surface temperature since industrialisation is caused by the increase in green house gases in the atmosphere, some people cite solar activity, either directly or through its effect on cosmic rays, as an underestimated contributor to such global warming. In this paper a simplified version of the standard picture of the role of greenhouse gases in causing the global warming since industrialisation is described. The conditions necessary for this picture to be wholly or partially wrong are then introduced. Evidence is presented from which the contributions of either cosmic rays or solar activity to this warming is deduced. The contribution is shown to be less than 10% of the warming seen in the twentieth century.

  10. Data Assimilation of Cosmic-ray Derived Soil Moisture

    NASA Astrophysics Data System (ADS)

    Rosolem, R.; Shuttleworth, W. J.; Arellano, A. F.; Hoar, T. J.; Zeng, X.; Zreda, M.; Franz, T. E.

    2012-12-01

    Soil moisture predicted by numerical models plays a key role in weather and seasonal climate projections. Nevertheless, intermediate-scale soil moisture measurements have been difficult to obtain due to small-scale heterogeneity of soil water content, making upscaling measurements to areas comparable to land surface model (LSM) grid size problematic. Real-time integrated soil moisture measurements at spatial scales of a few hundreds of meters and effective depth of tens of centimeters are now available from the COsmic-ray Soil Moisture Observing System (COSMOS). This paper describes the initial efforts to implement the data assimilation framework of COSMOS observations applied to LSMs. A physically-based and analytic model that calculates the above-ground fast neutron intensity from LSM-derived soil moisture profiles is introduced here. The COsmic-ray Soil Moisture Interaction Code (COSMIC) includes a description of (a) degradation of the incoming high energy neutron flux, (b) creation of fast neutrons at each depth in the soil, and (c) degradation of the resulting fast neutrons before they reach the soil surface. COSMIC has been implemented into the Data Assimilation Research Testbed (DART) in order to update the soil moisture status of the NOAH LSM given COSMOS fast neutron intensity measurements. Preliminary results show the soil water dynamics in NOAH being improved when compared to a network of 180 point-scale sensors placed within the COSMOS sensor footprint for a site near Tucson (Arizona). Comparison of surface energy and water fluxes are also shown for a number of selected COSMOS sites co-located with Ameriflux towers.

  11. Galactic cosmic ray modulation from 1965 1970

    Microsoft Academic Search

    I. H. Urch; L. J. Gleeson

    1972-01-01

    Numerical solutions of the cosmic-ray equation of transport within the solar cavity and including the effects of diffusion, convection, and energy losses due to adiabatic deceleration, have been used to reproduce the modulation of galactic electrons, protons and helium nuclei observed during the period 1965 1970. Kinetic energies between 10 and 104 MeV\\/nucleon are considered. Computed and observed spectra (where

  12. Cosmic Ray Induced Bit-Flipping Experiment

    NASA Astrophysics Data System (ADS)

    Pu, Ge; Callaghan, Ed; Parsons, Matthew; Cribflex Team

    2015-04-01

    CRIBFLEX is a novel approach to mid-altitude observational particle physics intended to correlate the phenomena of semiconductor bit-flipping with cosmic ray activity. Here a weather balloon carries a Geiger counter and DRAM memory to various altitudes; the data collected will contribute to the development of memory device protection. We present current progress toward initial flight and data acquisition. This work is supported by the Society of Physics Students with funding from a Chapter Research Award.

  13. Cosmic ray gradients in the outer heliosphere

    NASA Technical Reports Server (NTRS)

    Fillius, W.; Wake, B.; Ip, W.-H.; Axford, I.

    1983-01-01

    Launched in 1972 and 1973 respectively, the Pioneer 10 and 11 spacecraft are now probing the outer heliosphere on their final escape from the sun. The data in this paper extend for almost an entire solar cycle from launch to early 1983, when Pioneer 10 was at a heliocentric distance of 29 AU and Pioneer 11, 13 AU. The UCSD instruments on board were used to study the gradient, and to look at the time and spatial variations of the cosmic ray intensities.

  14. Scientific Set of Instruments "Solar Cosmic Rays"

    NASA Astrophysics Data System (ADS)

    Kuznetsov, S. N.; Bogomolov, A. V.; Galkin, V. I.; Denisov, Yu. I.; Podorolsky, A. N.; Ryumin, S. P.; Kudela, K.; Rojko, J.

    A set of scientific instruments SCR (Solar Cosmic Rays) was developed by the scientists of SINP MSU and IEP SAS in order to study relations between the radiation conditions in the near-Earth space and solar activity. This set of instruments was installed on board the satellites CORONAS-I and CORONAS-F launched to the orbit on March 2, 1994, and July 30, 2001, respectively. Detailed description of the instruments is presented.

  15. New aspects of heavy cosmic rays from calcium to nickel (Z = 20 to 28)

    NASA Technical Reports Server (NTRS)

    Mewaldt, Richard A.; Webber, W. R.

    1990-01-01

    Over the two year course of this grant a study was conducted to explore the implications of composition measurements of heavy cosmic rays made by the Third High Energy Astronomy Observatory (HEAO-3). To interpret these and other measurements this study combined for the first time new laboratory measurements of the fragmentation cross sections of heavy nuclei, a new semi-empirical cross section formula, and the latest in cosmic ray propagation and solar modulation models. These models were used to interpret abundance measurements from six recent satellite experiments, including, in particular, two from HEAO-3. The principal results of the study were: (1) an improved interpretation of the Mn-54 clock in cosmic rays, including predictions of the isotopic abundances of Mn for comparison with future isotope measurements; (2) the first realization of the effect of Mn-54 decay on studies of the source abundances of Fe isotopes; (3) improved source abundances of the elements Ar, Ca, Cr, Mn, Fe, and Ni in the cosmic ray source material; (4) an improved fit to the abundances of Fe secondaries in cosmic rays; and (5) additional evidence that supports the validity of the leaky-box model of cosmic ray propagation in the galaxy. This final report summarizes these new results, the new tools that were developed to obtain them, and presents a bibliography of talks and publications that resulted from this work.

  16. Axion-like particle effects on the polarization of cosmic high-energy gamma sources

    SciTech Connect

    Bassan, Nicola [SISSA, Via Beirut 2–4, 34014 Trieste (Italy); Mirizzi, Alessandro [II. Institut für theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Roncadelli, Marco, E-mail: nicola.bassan@sissa.it, E-mail: alessandro.mirizzi@desy.de, E-mail: marco.roncadelli@pv.infn.it [INFN, Sezione di Pavia, Via A. Bassi 6, 27100 Pavia (Italy)

    2010-05-01

    Various satellite-borne missions are being planned to measure the polarization of a large number of gamma-ray bursts (GRBs). We show that the polarization pattern resulting from the current models of GRB emission can be drastically modified by the existence of very light axion-like particles (ALPs), which are predicted by many extensions of the Standard Model of particle physics. Basically, the propagation of photons emitted by a GRB through cosmic magnetic fields with a domain-like structure induces photon-ALP mixing, which is expected to produce a strong modification of the initial photon polarization. Because of the random orientation of the magnetic field in each domain, this effect strongly depends on the orientation of the line of sight. As a consequence, photon-ALP conversion considerably broadens the initial polarization distribution. Searching for such a peculiar feature through future high-statistics polarimetric measurements therefore offers a new opportunity to discover very light ALPs.

  17. Comparison of cosmic ray flux at sqrt(s) > 14 TeV with LHC luminosity

    E-print Network

    Frank E. Taylor

    2008-05-29

    The high energy cosmic ray flux impinging on the sun and earth for 4 Gyr is compared to the operation of the CERN Large Hadron Collider (LHC) at design energy and luminosity. It is shown by two different calculations that both the integrated luminosity and the total hadronic interaction rate from the cosmic ray flux of comparable energy are many orders of magnitude larger than that of the LHC operated for 10 years. This study indicates that it is extremely unlikely that pernicious exotic particles, such as mini-black holes, would be produced by the LHC that would destroy the earth.

  18. Polarization correction for ionization loss in a galactic cosmic ray transport code (HZETRN)

    NASA Technical Reports Server (NTRS)

    Shinn, Judy L.; Farhat, Hamidullah; Badavi, Francis F.; Wilson, John W.

    1993-01-01

    An approximate polarization correction for ionization loss suggested by Sternheimer has been implemented in the galactic cosmic ray transport code (HZETRN) developed at the Langley Research Center. Sample calculations made for the aluminum shield and liquid hydrogen shield show no more than a plus or minus 2 percent change in the linear energy transfer (LET) distribution for flux compared with those without polarization correction. This very small change is expected because the effect of polarization correction on the reduction in stopping power of ions with energies above 2 GeV/amu is suppressed by the decrease in galactic cosmic ray ion flux at such high energies.

  19. Solar panels as cosmic-ray detectors

    E-print Network

    Stella, Carlo; Assis, Pedro; Brogueira, Pedro; Santo, Catarina Espirito; Goncalves, Patricia; Pimenta, Mario; De Angelis, Alessandro

    2014-01-01

    Due to fundamental limitations of accelerators, only cosmic rays can give access to centre-of- mass energies more than one order of magnitude above those reached at the LHC. In fact, extreme energy cosmic rays (1018 eV - 1020 eV) are the only possibility to explore the 100 TeV energy scale in the years to come. This leap by one order of magnitude gives a unique way to open new horizons: new families of particles, new physics scales, in-depth investigations of the Lorentz symmetries. However, the flux of cosmic rays decreases rapidly, being less than one particle per square kilometer per year above 1019 eV: one needs to sample large surfaces. A way to develop large-effective area, low cost, detectors, is to build a solar panel-based device which can be used in parallel for power generation and Cherenkov light detection. Using solar panels for Cherenkov light detection would combine power generation and a non-standard detection device.

  20. Astrophysics of Galactic charged cosmic rays

    E-print Network

    Castellina, Antonella

    2011-01-01

    A review is given of the main properties of the charged component of galactic cosmic rays, particles detected at Earth with an energy spanning from tens of MeV up to about 10^19 eV. After a short introduction to the topic and an historical overview, the properties of cosmic rays are discussed with respect to different energy ranges. The origin and the propagation of nuclei in the Galaxy are dealt with from a theoretical point of view. The mechanisms leading to the acceleration of nuclei by supernova remnants and to their subsequent diffusion through the inhomogeneities of the galactic magnetic field are discussed and some clue is given on the predictions and observations of fluxes of antimatter, both from astrophysical sources and from dark matter annihilation in the galactic halo. The experimental techniques and instrumentations employed for the detection of cosmic rays at Earth are described. Direct methods are viable up to 10^14 eV, by means of experiments flown on balloons or satellites, while above that ...

  1. Optics for high energy x-ray scattering applications (invited)

    NASA Astrophysics Data System (ADS)

    Tschentscher, Thomas

    1996-09-01

    High energy photons in the range from 80 to 500 keV are a relatively new tool, which is provided with sufficient fluxes only by the latest generation of synchrotron sources. Due to the high energies and, respectively, very short wavelengths, new arrangements for monochromators or mirrors have to be investigated in addition to standard monochromator concepts. An overview of possible monochromator setups is given and the need for experiments to be performed at these energies is evaluated. Low absorption enables the use of rather thick absorbers in order to reduce the heat load problem, which is due to the high power synchrotron beam. Even monochromator crystals become semitransparent, thus giving the possibility of operating more than one experimental station using the same synchrotron beam. Focusing techniques may be applied, and monochromators with an increased bandwidth are of interest for providing sufficient monochromatic flux. The optical concept of the High Energy beamline ID15 at the ESRF is presented, where two different insertion devices can be used alternatingly. Monochromatic beam in the range from 30 to 80 keV is provided by the use of bent cooled Si monochromators and the results of the performance tests are shown.

  2. Cosmic Ray and Tev Gamma Ray Generation by Quasar Remnants

    NASA Technical Reports Server (NTRS)

    Boldt, Elihu; Loewenstein, Michael; White, Nicholas E. (Technical Monitor)

    2000-01-01

    Results from new broadband (radio to X-ray) high-resolution imaging studies of the dormant quasar remnant cores of nearby giant elliptical galaxies are now shown to permit the harboring of compact dynamos capable of generating the highest energy cosmic ray particles and associated curvature radiation of TeV photons. Confirmation would imply a global inflow of interstellar gas all the way to the accretion powered supermassive black hole at the center of the host galaxy.

  3. Cosmic X-ray background and solitars.

    NASA Astrophysics Data System (ADS)

    Chiu, H.-Y.

    In this paper the authors has examined the observational consequences of a class of new astronomical objects proposed by Friedberg, Lee and Pang, called solitars which are degenerate vacuum states embedded with particles. A study is made to include finite temperature effect and pair creation. Quark is believed to be the only species that can exist in the interior of solitars. Massive quark solitars are primarily X-ray emitters and may account for the large unexplained thermal component of the cosmic X-ray background.

  4. Energy Spectrum of Cosmic-Ray Electrons at TeV Energies

    SciTech Connect

    Aharonian, F. [Max-Planck-Institut fuer Kernphysik, P.O. Box 103980, D 69029 Heidelberg (Germany); Dublin Institute for Advanced Studies, 5 Merrion Square, Dublin 2 (Ireland); Akhperjanian, A. G.; Sahakian, V. [Yerevan Physics Institute, 2 Alikhanian Brothers Street, 375036 Yerevan (Armenia); Barres de Almeida, U.; Chadwick, P. M.; Cheesebrough, A.; Dickinson, H. J.; Hadjichristidis, C.; Keogh, D.; McComb, T. J. L.; Nolan, S. J.; Orford, K. J.; Osborne, J. L.; Rayner, S. M.; Rulten, C. B.; Spangler, D.; Ward, M. [University of Durham, Department of Physics, South Road, Durham DH1 3LE (United Kingdom); Bazer-Bachi, A. R.; Borrel, V.; Olive, J-F. [Centre d'Etude Spatiale des Rayonnements, CNRS/UPS, 9 av. du Colonel Roche, BP 4346, F-31029 Toulouse Cedex 4 (France)] (and others)

    2008-12-31

    The very large collection area of ground-based {gamma}-ray telescopes gives them a substantial advantage over balloon or satellite based instruments in the detection of very-high-energy (>600 GeV) cosmic-ray electrons. Here we present the electron spectrum derived from data taken with the High Energy Stereoscopic System (H.E.S.S.) of imaging atmospheric Cherenkov telescopes. In this measurement, the first of this type, we are able to extend the measurement of the electron spectrum beyond the range accessible to direct measurements. We find evidence for a substantial steepening in the energy spectrum above 600 GeV compared to lower energies.

  5. The Application of High Energy X Rays and Electron Beams in Radiotherapy

    Microsoft Academic Search

    J. A. Purdy

    1979-01-01

    It has been more than 25 years since very high energy x rays generated by a betatron were first used in the treatment of cancer. The development of these machines along with linear accelerators quickly led to the use of high energy electrons as an additional modality in cancer management. In the intervening years, the physical and biological aspects of

  6. A search for bursts of very high energy gamma rays with Milagro

    NASA Astrophysics Data System (ADS)

    Vasileiou, Vlasios

    Milagro is a water-Cherenkov detector that observes the extended air showers produced by cosmic gamma rays of energies E [Special characters omitted.] 100 GeV. The effective area of Milagro peaks at energies E [Special characters omitted.] 10 TeV, however it is still large even down to a few hundred GeV (~ 10 m 2 at 100 GeV ). The wide field of view (~ 2 sr ) and high duty cycle (> 90%) of Milagro make it ideal for continuously monitoring the overhead sky for transient Very High Energy (VHE) emissions. This study searched the Milagro data for such emissions. Even though the search was optimized primarily for detecting the emission from Gamma-Ray Bursts (GRBs), it was still sensitive to the emission from the last stages of the evaporation of Primordial Black Holes (PBHs) or to any other kind of phenomena that produce bursts of VHE gamma rays. Measurements of the GRB spectra by satellites up to few tens of GeV showed no signs of a cutoff. Even though multiple instruments sensitive to GeV/TeV gamma rays have performed observations of GRBs, there has not yet been a definitive detection of such an emission yet. One of the reasons for that is that gamma rays with energies E [Special characters omitted.] 100 GeV are attenuated by interactions with the extragalactic background light or are absorbed internally at the site of the burst. There are many models that predict VHE gamma-ray emission from GRBs. A detection or a constraint of such an emission can provide useful information on the mechanism and environment of GRBs. This study performed a blind search of the Milagro data of the last five years for bursts of VHE gamma rays with durations ranging from 100 ms to 316 s. No GRB localization was provided by an external instrument. Instead, the whole dataset was thoroughly searched in time, space, and duration. No significant events were detected. Upper limits were placed on the VHE emission from GRBs.

  7. MILAGRO CONSTRAINTS ON VERY HIGH ENERGY EMISSION FROM SHORT-DURATION GAMMA-RAY BURSTS

    E-print Network

    California at Santa Cruz, University of

    MILAGRO CONSTRAINTS ON VERY HIGH ENERGY EMISSION FROM SHORT-DURATION GAMMA-RAY BURSTS A. A. Abdo,1 localizations of short, hard gamma-ray bursts (GRBs) by the Swift and HETE satellites have led-duration (gamma-ray

  8. Very High Energy Gamma Ray Extension of GRO Observations

    NASA Technical Reports Server (NTRS)

    Weekes, Trevor C.

    1994-01-01

    The membership, progress, and invited talks, publications, and proceedings made by the Whipple Gamma Ray Collaboration is reported for june 1990 through May 1994. Progress was made in the following areas: the May 1994 Markarian Flare at Whipple and EGRET (Energetic Gamma Ray Experiment Telescope) energies; AGN's (Active Galactic Nuclei); bursts; supernova remnants; and simulations and energy spectra.

  9. Observation of TeV-Energy Cosmic-Ray Anisotropy with the HAWC Observatory

    NASA Astrophysics Data System (ADS)

    Fiorino, Daniel W.

    Over the past two decades, ground-based measurements of the arrival directions of TeV cosmic rays have revealed an unexpected anisotropy. Multiple detectors have recorded fluxes above all-sky averages to high statistical significance for features at large (about 180°) and small (about 5°) angular sizes. Likely sources of high-energy cosmic rays are no closer than about 100 pc, about 100,000 Larmor radii for a TeV proton in typical interstellar magnetic fields of order several microGauss. This thesis outlines methods to search for signals in cosmic-ray arrival directions on data from the High-Altitude Water Cherenkov (HAWC) Observatory -- an extended air shower detector array in Puebla, Mexico, sensitive to gamma rays and cosmic rays at TeV energies. The detector is currently under construction, but data acquisition with the partially deployed detector started in 2013. An analysis of the cosmic-ray arrival direction distribution based on 86 billion events recorded between June 2013 and July 2014 shows anisotropy at the 10. (-4) level on angular scales of about 10°. The HAWC cosmic-raysky map exhibits three regions of significantly enhanced cosmic-ray flux; two of these regions were first reported by the Milagro experiment. A third region coincides with an excess recently reported by the ARGO-YBJ experiment. An angular power spectrum analysis of the sky shows that all terms up to l=15 contribute significantly to the excesses. Large angular scales (>60°) are also considered, but the results are still preliminary as they are contaminated with non-sidereal signals which cancel for integer years of continuous data. An analysis of the cosmic-ray Moon shadow is shown to demonstrate the angular resolution and energy scale of the data set and to evaluate part of the analysis technique.

  10. The Systematic Interpretation of Cosmic Ray Data (The Transport Project)

    NASA Technical Reports Server (NTRS)

    Guzik, T. Gregory

    1997-01-01

    The Transport project's primary goals were to: (1) Provide measurements of critical fragmentation cross sections; (2) Study the cross section systematics; (3) Improve the galactic cosmic ray propagation methodology; and (4) Use the new cross section measurements to improve the interpretation of cosmic ray data. To accomplish these goals a collaboration was formed consisting of researchers in the US at Louisiana State University (LSU), Lawrence Berkeley Laboratory (LBL), Goddard Space Flight Center (GSFC), the University of Minnesota (UM), New Mexico State University (NMSU), in France at the Centre d'Etudes de Saclay and in Italy at the Universita di Catania. The US institutions, lead by LSU, were responsible for measuring new cross sections using the LBL HISS facility, analysis of these measurements and their application to interpreting cosmic ray data. France developed a liquid hydrogen target that was used in the HISS experiment and participated in the data interpretation. Italy developed a Multifunctional Neutron Spectrometer (MUFFINS) for the HISS runs to measure the energy spectra, angular distributions and multiplicities of neutrons emitted during the high energy interactions. The Transport Project was originally proposed to NASA during Summer, 1988 and funding began January, 1989. Transport was renewed twice (1991, 1994) and finally concluded at LSU on September, 30, 1997. During the more than 8 years of effort we had two major experiment runs at LBL, obtained data on the interaction of twenty different beams with a liquid hydrogen target, completed the analysis of fifteen of these datasets obtaining 590 new cross section measurements, published nine journal articles as well as eighteen conference proceedings papers, and presented more than thirty conference talks.

  11. AXAF Detector Backgrounds Produced By Cosmic Ray Protons

    NASA Technical Reports Server (NTRS)

    Armstrong, T. W.; Colborn, K. L.; Dietz, K. L.; O'Dell, S. L.; Weisskopf, M. C.

    1997-01-01

    One of the science instruments on the Advanced X-ray Astrophysics Facility (AXAF), planned for launch in 1998 into a highly elliptical (10,000 km x 140,000 km) orbit, is a microchannel plate High Resolution Camera (HRC). This detector is designed to provide imaging and spectroscopic observations of x-rays emitted by stellar sources in the 0.1 to 10 keV energy range. Described here are analyses made to determine the expected time-dependent detector background from prompt and delayed (activation) radiation initiated by galactic cosmic-ray (GCR) proton interactions in the spacecraft and payload. Numerical simulations were made using the coupled set of Monte Carlo radiation transport codes, analysis software, and data bases shown. The major codes are HETC for nucleon-meson transport, EGS for simulating electromagnetic cascades, and MORSE for low-energy (less than 15 MeV) neutron transport. The simulation follows the transport history of photons in the energy range from - 100 GeV down to approx. 0.1 keV due to gamma-ray sources from neutral pion decay, high-energy (spallation) collisions, and low-energy neutron inelastic scattering and capture reactions. Also included is radioisotope production and the tracking of gamma-rays, electrons, and positrons from induced radioactivity.

  12. AXAF Detector Backgrounds Produced By Cosmic Ray Protons

    NASA Astrophysics Data System (ADS)

    Armstrong, T. W.; Colborn, K. L.; Dietz, K. L.; O'dell, S. L.; Weisskopf, M. C.

    One of the science instruments on the Advanced X-ray Astrophysics Facility (AXAF), planned for launch in 1998 into a highly elliptical (10,000 km x 140,000 km) orbit, is a microchannel plate High Resolution Camera (HRC). This detector is designed to provide imaging and spectroscopic observations of x-rays emitted by stellar sources in the 0.1 to 10 keV energy range. Described here are analyses made to determine the expected time-dependent detector background from prompt and delayed (activation) radiation initiated by galactic cosmic-ray (GCR) proton interactions in the spacecraft and payload. Numerical simulations were made using the coupled set of Monte Carlo radiation transport codes, analysis software, and data bases shown. The major codes are HETC for nucleon-meson transport, EGS for simulating electromagnetic cascades, and MORSE for low-energy (less than 15 MeV) neutron transport. The simulation follows the transport history of photons in the energy range from - 100 GeV down to approx. 0.1 keV due to gamma-ray sources from neutral pion decay, high-energy (spallation) collisions, and low-energy neutron inelastic scattering and capture reactions. Also included is radioisotope production and the tracking of gamma-rays, electrons, and positrons from induced radioactivity.

  13. Modulated High-Energy Gamma-Ray Emission from the Microquasar Cygnus X-3

    Microsoft Academic Search

    A. A. Abdo; M. Ackermann; M. Axelsson; L. Baldini; J. Ballet; G. Barbiellini; D. Bastieri; B. M. Baughman; K. Bechtol; R. Bellazzini; B. Berenji; R. D. Blandford; E. D. Bloom; E. Bonamente; A. W. Borgland; A. Brez; M. Brigida; P. Bruel; T. H. Burnett; S. Buson; G. A. Caliandro; R. A. Cameron; P. A. Caraveo; J. M. Casandjian; C. Cecchi; Ö. Çelik; S. Chaty; C. C. Cheung; J. Chiang; S. Ciprini; R. Claus; J. Cohen-Tanugi; L. R. Cominsky; J. Conrad; S. Corbel; R. Corbet; C. D. Dermer; F. de Palma; S. W. Digel; E. do Couto e Silva; P. S. Drell; R. Dubois; G. Dubus; D. Dumora; C. Farnier; C. Favuzzi; S. J. Fegan; W. B. Focke; P. Fortin; M. Frailis; P. Fusco; F. Gargano; N. Gehrels; S. Germani; G. Giavitto; B. Giebels; N. Giglietto; F. Giordano; T. Glanzman; G. Godfrey; I. A. Grenier; M.-H. Grondin; J. E. Grove; L. Guillemot; S. Guiriec; Y. Hanabata; A. K. Harding; M. Hayashida; E. Hays; A. B. Hill; L. Hjalmarsdotter; D. Horan; R. E. Hughes; M. S. Jackson; G. Jóhannesson; A. S. Johnson; T. J. Johnson; W. N. Johnson; T. Kamae; H. Katagiri; N. Kawai; M. L. Kocian; J. Knödlseder; E. Koerding; M. Kuss; J. Lande; J. Latronico; M. Lemoine-Goumard; F. Longo; F. Loparco; B. Lott; M. N. Lovellette; P. Lubrano; G. M. Madejski; A. Makeev; L. Marchand; M. N. Mazziotta; W. Max-Moerbeck; N. McColl; J. E. McEnery; C. Meurer; P. F. Michelson; S. Migliari; W. Mitthumsiri; T. Mizuno; C. Monte; M. E. Monzani; A. Morselli; I. V. Moskalenko; S. Murgia; P. L. Nolan; J. P. Norris; E. Nuss; T. Ohsugi; N. Omodei; R. A. Ong; J. F. Ormes; D. Paneque; D. Parent; V. Pelassa; M. Pepe; M. Pesce-Rollins; F. Piron; G. Pooley; T. A. Porter; K. Pottschmidt; S. Rainò; R. Rando; P. S. Ray; M. Razzano; N. Rea; A. Readhead; A. Reimer; O. Reimer; J. L. Richards; L. S. Rochester; J. Rodriguez; A. Y. Rodriguez; R. W. Romani; F. Ryde; H. F.-W. Sadrozinski; A. Sander; P. M. Saz Parkinson; C. Sgrò; E. J. Siskind; D. A. Smith; P. D. Smith; P. Spinelli; J.-L. Starck; M. Stevenson; M. S. Strickman; D. J. Suson; H. Takahashi; T. Tanaka; J. B. Thayer; D. J. Thompson; L. Tibaldo; J. A. Tomsick; D. F. Torres; G. Tosti; A. Tramacere; Y. Uchiyama; T. L. Usher; V. Vasileiou; N. Vilchez; V. Vitale; A. P. Waite; P. Wang; J. Wilms; B. L. Winer; K. W. Wood; T. Ylinen; M. Ziegler

    2009-01-01

    Microquasars are accreting black holes or neutron stars in binary systems with associated relativistic jets. Despite their frequent outburst activity, they have never been unambiguously detected emitting high-energy gamma rays. The Fermi Large Area Telescope (LAT) has detected a variable high-energy source coinciding with the position of the x-ray binary and microquasar Cygnus X-3. Its identification with Cygnus X-3 is

  14. Cosmic-ray interactions and dating of meteorite stranding surfaces with cosmogenic nuclides

    SciTech Connect

    Reedy, R.C.

    1988-01-01

    A wide variety of products from cosmic-ray interactions have been measured in terrestrial or extraterrestrial samples. These ''cosmogenic'' products include radiation damage tracks and rare nuclides that are made by nuclear reactions. They often have been used to determine the fluxes and composition of cosmic-ray particles in the past, but they are usually used to study the history of the ''target'' (such as the time period that it was exposed to cosmic-ray particles). Products made by both the high-energy galactic cosmic rays and energetic particles emitted irregularly from the Sun have been extensively studied. Some of these cosmogenic products, especially nuclides, have been or can be applied to studies of Antarctic meteorite stranding surfaces, the ice surfaces in Antarctica where meteorites have been found. Cosmogenic nuclides studied in samples from Antarctica and reported by others elsewhere in this volume include those in meteorites, especially radionuclides used to determine terrestrial ages, and those made in situ in terrestrial rocks. Cosmogenic nuclides made in the Earth's atmosphere or brought in with cosmic dust have also been studied in polar ice, and it should also be possible to measure nuclides made in situ in ice. As an introduction to cosmogenic nuclides and their applications, cosmic rays and their interactions will be presented below and production systematics of cosmogenic nuclides in these various media will be discussed later. 20 refs., 2 tabs.

  15. Acceleration and Particle Field Interactions of Cosmic Rays I: Formalism

    E-print Network

    A. Tawfik; A. Saleh; M. T. Ghoneim; A. A. Hady

    2010-10-14

    The acceleration of ultra high energy cosmic rays is conjectured to occur through various interactions with the electromagnetic fields in different astrophysical objects, like magnetic matter clumps, besides the well-known shock and stochastic Fermi mechanisms. It is apparent that the latter are not depending on the particle's charge, quantitatively. Based on this model, a considerable portion of the dynamics, that derives a charged particle parallel to a magnetic field $\\mathbf{B}$ and under the influence of a force $\\mathbf{F}$, is assumed to be composed of an acceleration by a non-magnetic force $\\mathbf{F}_{\\parallel}$ and a gyromotion along $\\mathbf{B}$ direction, plus drifts in the direction of $\\mathbf{F}_{\\perp}$. The model and its formalism are introduced. Various examples for drift motions and accelerating forces are suggested. The formalism is given in a non-relativistic version. Obviously, the translation into the relativistic version is standard. In a forthcoming work, a quantitative estimation of the energy gained by charged cosmic rays in various astrophysical objects will be evaluated.

  16. The Galactic magnetic deflection of Cosmic Rays from Cen A

    NASA Astrophysics Data System (ADS)

    Keivani, Azadeh; Farrar, Glennys

    2013-04-01

    We present the results of propagating ultra-high energy cosmic rays (UHECRs) from Centaurus A, to characterize their arrival-direction locus and determine whether Cen A can be a significant source of the UHECR excess reported by the Pierre Auger Observatory within 18 degrees of Cen A. We use the recent galactic magnetic field model of Jansson and Farrar (JF12), a 35-parameter model which includes coherent, striated and random components and is constrained by WMAP synchrotron maps and all available extragalactic rotation measures. We also present a new method to increase the efficiency of forward-tracking the UHECRs through the galactic magnetic field. Simulations are done for rigidities E/Z = 64 EV down to 1 EV, thus covering the possibility of compositions as heavy as Fe for the published UHECR events.

  17. Commissioning of the ATLAS Muon Spectrometer with Cosmic Rays

    E-print Network

    The ATLAS Collaboration

    2010-08-02

    The ATLAS detector at the Large Hadron Collider has collected several hundred million cosmic ray events during 2008 and 2009. These data were used to commission the Muon Spectrometer and to study the performance of the trigger and tracking chambers, their alignment, the detector control system, the data acquisition and the analysis programs. We present the performance in the relevant parameters that determine the quality of the muon measurement. We discuss the single element efficiency, resolution and noise rates, the calibration method of the detector response and of the alignment system, the track reconstruction efficiency and the momentum measurement. The results show that the detector is close to the design performance and that the Muon Spectrometer is ready to detect muons produced in high energy proton-proton collisions.

  18. Superluminal Particles, Cosmology and Cosmic-Ray Physics

    NASA Astrophysics Data System (ADS)

    Gonzalez-Mestres, Luis

    2003-07-01

    Non-tachyonic superluminal sectors of matter (sup erbradyons), with critical speeds in vacuum much larger than the speed of light, can quite naturally exist and play an important role in both cosmic-ray physics (anomalous high-energy events) and cosmology (big-bang physics, alternatives to inflation, dark matter...). They can even be the real "elementary" particles. An up dated discussion of the sub ject is presented, in relation with recent theoretical and experimental results. Prosp ects for future searches are also reexamined. Lorentz symmetry violation (LSV) models based on mixing with superbradyons are compared with LDRK (linearly deformed relativistic kinematics) and QDRK (quadratically deformed relativistic kinematics) such as defined in our previous paper physics/0003080 .

  19. Energy calibration of a cosmic ray ionization spectrometer

    NASA Technical Reports Server (NTRS)

    Whiteside, H.; Crannell, C. J.; Crannell, H.; Ormes, J. F.; Ryan, M. J.; Jones, W. V.

    1972-01-01

    The NASA/GSFC high energy cosmic ray experiment was calibrated during the summer of 1970 using protons and pions with energies from 9.3 GeV to 17.6 GeV. The best measure found for the energy E of an incoming primary particle is sigma I, the total number of ionizing particles observed in the instrument, summed over the various iron modules. The resolution in the calibration energy range is about + or - 30 percent (s.d.) over a wide range of incident angles and positions. The calibration function may be parameterized as e = sigma I/K, where K is predominantly a function of the location of the first interaction and the trajectory of the incoming particle.

  20. Commissioning of the ATLAS Muon Spectrometer with Cosmic Rays

    E-print Network

    Aad, Georges; Abdallah, Jalal; Abdelalim, Ahmed Ali; Abdesselam, Abdelouahab; Abdinov, Ovsat; Abi, Babak; Abolins, Maris; Abramowicz, Halina; Abreu, Henso; Acharya, Bobby Samir; Adams, David; Addy, Tetteh; Adelman, Jahred; Adorisio, Cristina; Adragna, Paolo; Adye, Tim; Aefsky, Scott; Aguilar-Saavedra, Juan Antonio; Aharrouche, Mohamed; Ahlen, Steven; Ahles, Florian; Ahmad, Ashfaq; Ahmed, Hossain; Ahsan, Mahsana; Aielli, Giulio; Akdogan, Taylan; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov , Andrei; Aktas, Adil; Alam, Mohammad; Alam, Muhammad Aftab; Albrand, Solveig; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Aliev, Malik; Alimonti, Gianluca; Alison, John; Aliyev, Magsud; Allport, Phillip; Allwood-Spiers, Sarah; Almond, John; Aloisio, Alberto; Alon, Raz; Alonso, Alejandro; Alviggi, Mariagrazia; Amako, Katsuya; Amelung, Christoph; Amorim, Antonio; Amorós, Gabriel; Amram, Nir; Anastopoulos, Christos; Andeen, Timothy; Anders, Christoph Falk; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angerami, Aaron; Anghinolfi, Francis; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonelli, Stefano; Antos, Jaroslav; Antunovic, Bijana; Anulli, Fabio; Aoun, Sahar; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Arce, Ayana; Archambault, John-Paul; Arfaoui, Samir; Arguin, Jean-Francois; Argyropoulos, Theodoros; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnault, Christian; Artamonov, Andrei; Arutinov, David; Asai, Makoto; Asai, Shoji; Silva, José; Asfandiyarov, Ruslan; Ask, Stefan; Åsman, Barbro; Asner, David; Asquith, Lily; Assamagan, Ketevi; Astbury, Alan; Astvatsatourov, Anatoli; Atoian, Grigor; Auerbach, Benjamin; Augsten, Kamil; Aurousseau, Mathieu; Austin, Nicholas; Avolio, Giuseppe; Avramidou, Rachel Maria; Axen, David; Ay, Cano; Azuelos, Georges; Azuma, Yuya; Baak, Max; Bach, Andre; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Badescu, Elisabeta; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Mark; Baker, Oliver Keith; Baker, Sarah; Baltasar Dos Santos Pedrosa, Fernando; Banas, Elzbieta; Banerjee, Piyali; Banerjee, Swagato; Banfi, Danilo; Bangert, Andrea Michelle; Bansal, Vikas; Baranov, Sergey; Baranov, Sergei; Barashkou, Andrei; Barber, Tom; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Bardin, Dmitri; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnett, Bruce; Barnett, Michael; Baroncelli, Antonio; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Barrillon, Pierre; Bartoldus, Rainer; Bartsch, Detlef; Bates, Richard; Batkova, Lucia; Batley, Richard; Battaglia, Andreas; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Bazalova, Magdalena; Beare, Brian; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Becerici, Neslihan; Bechtle, Philip; Beck, Graham; Beck, Hans Peter; Beckingham, Matthew; Becks, Karl-Heinz; Beddall, Ayda; Beddall, Andrew; Bednyakov, Vadim; Bee, Christopher; Begel, Michael; Behar Harpaz, Silvia; Behera, Prafulla; Beimforde, Michael; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellina, Francesco; Bellomo, Massimiliano; Belloni, Alberto; Belotskiy, Konstantin; Beltramello, Olga; Ben Ami, Sagi; Benary, Odette; Benchekroun, Driss; Bendel, Markus; Benedict, Brian Hugues; Benekos, Nektarios; Benhammou, Yan; Benincasa, Gianpaolo; Benjamin, Douglas; Benoit, Mathieu; Bensinger, James; Benslama, Kamal; Bentvelsen, Stan; Beretta, Matteo; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Berglund, Elina; Beringer, Jürg; Bernat, Pauline; Bernhard, Ralf; Bernius, Catrin; Berry, Tracey; Bertin, Antonio; Besana, Maria Ilaria; Besson, Nathalie; Bethke, Siegfried; Bianchi, Riccardo-Maria; Bianco, Michele; Biebel, Otmar; Biesiada, Jed; Biglietti, Michela; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet; Bini, Cesare; Biscarat, Catherine; Bitenc, Urban; Black, Kevin; Blair, Robert; Blanchard, Jean-Baptiste; Blanchot, Georges; Blocker, Craig; Blondel, Alain; Blum, Walter; Blumenschein, Ulrike; Bobbink, Gerjan; Bocci, Andrea; Boehler, Michael; Boek, Jennifer; Boelaert, Nele; Böser, Sebastian; Bogaerts, Joannes Andreas; Bogouch, Andrei; Bohm, Christian; Bohm, Jan; Boisvert, Veronique; Bold, Tomasz; Boldea, Venera; Bondarenko, Valery; Bondioli, Mario; Boonekamp, Maarten; Bordoni, Stefania; Borer, Claudia; Borisov, Anatoly; Borissov, Guennadi; Borjanovic, Iris; Borroni, Sara; Bos, Kors

    2010-01-01

    The ATLAS detector at the Large Hadron Collider has collected several hundred million cosmic ray events during 2008 and 2009. These data were used to commission the Muon Spectrometer and to study the performance of the trigger and tracking chambers, their alignment, the detector control system, the data acquisition and the analysis programs. We present the performance in the relevant parameters that determine the quality of the muon measurement. We discuss the single element efficiency, resolution and noise rates, the calibration method of the detector response and of the alignment system, the track reconstruction efficiency and the momentum measurement. The results show that the detector is close to the design performance and that the Muon Spectrometer is ready to detect muons produced in high energy proton-proton collisions.