English
Related papers

Related papers: Pulsars Do Not Produce Sharp Features in the Cosmi…

200 papers

Pulsars have been invoked to explain the origin of recently observed high-energy Galactic cosmic-ray positrons. Since the positron propagation distance decreases with energy, the number of pulsars that can contribute to the observed…

High Energy Astrophysical Phenomena · Physics 2018-07-18 Ilias Cholis , Tanvi Karwal , Marc Kamionkowski

Recent results from the PAMELA satellite indicate the presence of a large flux of positrons (relative to electrons) in the cosmic ray spectrum between approximately 10 and 100 GeV. As annihilating dark matter particles in many models are…

Astrophysics · Physics 2010-04-15 Dan Hooper , Pasquale Blasi , Pasquale Dario Serpico

In this paper, we study the flux of electrons and positrons injected by pulsars and by annihilating or decaying dark matter in the context of recent ATIC, PAMELA, Fermi, and HESS data. We review the flux from a single pulsar and derive the…

High Energy Astrophysical Phenomena · Physics 2009-09-17 Dmitry Malyshev , Ilias Cholis , Joseph Gelfand

This review concentrates on the results obtained, over the last ten years, on the astrophysics of high-energy cosmic ray electrons and positrons. The anomalies, observed in the data of recent experiments (possible bump in the electron…

High Energy Astrophysical Phenomena · Physics 2013-03-26 A. D. Panov

We study the prospects for discriminating between the dark matter (DM) and pulsar origin of the PAMELA positron excess with the Alpha Magnetic Spectrometer AMS-02. We simulate the response of AMS-02 to positrons (and electrons) originating…

High Energy Astrophysical Phenomena · Physics 2011-01-27 Miguel Pato , Massimiliano Lattanzi , Gianfranco Bertone

Despite significant efforts over the past decade, the origin of the cosmic ray positron excess has still not been unambiguously established. A popular class of candidate sources are pulsars or pulsar wind nebulae but these cannot also…

High Energy Astrophysical Phenomena · Physics 2021-12-13 Philipp Mertsch , Andrea Vittino , Subir Sarkar

Several cosmic ray experiments have measured the positron fraction up to few hundred GeV. Their data have revealed an excess of positrons above 10 GeV that is not consistent with the secondary production of these particles in the…

High Energy Astrophysical Phenomena · Physics 2013-07-22 S. Della Torre , M. Gervasi , P. G. Rancoita , D. Rozza , A. Treves

The excesses in the electron and positron spectra observed by many experiments, such as PAMELA and AMS-02, have sparked significant theoretical investigation. It is not easy to distinguish the two primary hypotheses dark matter…

High Energy Astrophysical Phenomena · Physics 2024-11-07 Xing-Jian Lv , Xiao-Jun Bi , Kun Fang , Peng-Fei Yin , Meng-Jie Zhao

The rise of the cosmic ray positron fraction with energy, as first observed with high confidence by PAMELA, implies that a large flux of high energy positrons has been recently (or is being currently) injected into the local volume of the…

High Energy Astrophysical Phenomena · Physics 2013-08-13 Ilias Cholis , Dan Hooper

Cosmic-ray positrons have long been considered a powerful probe of dark matter annihilation. In particular, myriad studies of the unexpected rise in the positron fraction have debated its dark matter or pulsar origins. In this paper, we…

High Energy Astrophysical Phenomena · Physics 2022-01-07 Isabelle John , Tim Linden

The excesses of the cosmic positron fraction recently measured by PAMELA and the electron spectra by ATIC, PPB-BETS, Fermi and H.E.S.S. indicate the existence of primary electron and positron sources. The possible explanations include dark…

Astrophysics · Physics 2009-09-02 Juan Zhang , Xiao-jun Bi , Jia Liu , Si-Ming Liu , Peng-fei Yin , Qiang Yuan , Shou-hua Zhu

The Alpha Magnetic Spectrometer (AMS-02) has provided unprecedented precision measurements of the electron and positron cosmic-ray fluxes and the positron fraction spectrum. At the higher energies, sources as energetic local pulsars, may…

High Energy Astrophysical Phenomena · Physics 2023-03-15 Ilias Cholis , Thressay Hoover

Recent measurements of the Geminga and B0656+14 pulsars by the gamma-ray telescope HAWC (along with earlier measurements by Milagro) indicate that these objects generate significant fluxes of very high-energy electrons. In this paper, we…

High Energy Astrophysical Phenomena · Physics 2017-11-22 Dan Hooper , Ilias Cholis , Tim Linden , Ke Fang

The data collected by ATIC, PPB-BETS, FERMI-LAT and HESS all indicate that there is an electron/positron excess in the cosmic ray energy spectrum above $\sim$ 100 GeV, although different instrumental teams do not agree on the detailed…

High Energy Astrophysical Phenomena · Physics 2013-01-18 Yi-Zhong Fan , Bing Zhang , Jin Chang

The spectra of many X-ray pulsars show, in addition to a power law, a low-energy component that has often been modeled as a blackbody with kT ~ 0.1 keV. However the physical origin of this soft excess has remained a mystery. We examine a…

Astrophysics · Physics 2009-11-10 Ryan C. Hickox , Ramesh Narayan , Timothy R. Kallman

We investigate, in terms of production from pulsars and their nebulae, the cosmic ray positron and electron fluxes above $\sim10$ GeV, observed by the AMS-02 experiment up to 1 TeV. We concentrate on the Vela-X case. Starting from the…

High Energy Astrophysical Phenomena · Physics 2015-08-10 S. Della Torre , M. Gervasi , P. G. Rancoita , D. Rozza , A. Treves

We present a model for the gamma-ray emission of pulsars in terms of curvature radiation by highly relativistic particles. It is shown that the injection of power-law primary particles from an outer gap and subsequent cooling by curvature…

Astrophysics · Physics 2007-05-23 A. R. Crusius-Waetzel , H. Lesch

The flux of cosmic-ray high-energy positrons has recently been measured by AMS with unprecedented precision. This flux is well above the expectation from secondary positrons made by the observed fluxes of nuclear cosmic rays impinging on…

High Energy Physics - Phenomenology · Physics 2019-09-05 A. De Rújula

Electron and positron fluxes in cosmic rays are currently measured with unprecedented precision by AMS-02 up to TeV energies, and represent unique probes for the local properties of our Galaxy. The interpretation of their spectra is at…

High Energy Astrophysical Phenomena · Physics 2022-09-13 Silvia Manconi

Pulsars are believed to be sources of relativistic electrons and positrons. The abundance of detections of gamma-ray millisecond pulsars by Fermi Large Area Telescope coupled with their light curve characteristics that imply copious pair…

High Energy Astrophysical Phenomena · Physics 2015-06-23 C. Venter , A. Kopp , P. L. Gonthier , A. K. Harding , I. Büsching
‹ Prev 1 2 3 10 Next ›