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Related papers: Electron and positron spectra in the three dimensi…

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We use three dimensional time-dependent Schr\"odinger equation (3D--TDSE) to calculate angular electron momentum distributions and photoelectron spectra of atoms driven by spatially inhomogeneous fields. An example for such inhomogeneous…

Atomic Physics · Physics 2013-06-26 M. F. Ciappina , J. A. Pérez-Hernández , T. Shaaran , L. Roso , M. Lewenstein

The measurement of an excess in the cosmic-ray electron spectrum between 300 and 800 GeV by the ATIC experiment has - together with the PAMELA detection of a rise in the positron fraction up to 100 GeV - motivated many interpretations in…

High Energy Astrophysical Phenomena · Physics 2012-08-27 H. E. S. S. Collaboration , : , F. Aharonian

Recent measurements revealed the presence of several features in the cosmic ray spectrum. In particular, the proton and helium spectra exhibit a spectral hardening at $\approx$ 300 GV and a spectral steeping at $\approx$ 15 TV, followed by…

High Energy Astrophysical Phenomena · Physics 2024-12-04 Sarah Recchia , Stefano Gabici

A Galactic cosmic-ray transport model featuring non-homogeneous transport has been developed over the latest years. This setup is aimed at reproducing gamma-ray observations in different regions of the Galaxy (with particular focus on the…

High Energy Astrophysical Phenomena · Physics 2022-10-18 Pedro De la Torre Luque , Daniele Gaggero , Dario Grasso

Recent observations reveal that spectral breaks at ~GeV are commonly present in Galactic gamma-ray supernova remnants (SNRs) interacting with molecular clouds and that most of them have a spectral ($E^2dF/dE$) "platform" extended from the…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Hui Li , Yang Chen

The Fermi Large Area Telescope (LAT) collaboration recently released the updated results of the measurement of the cosmic ray electron (CRE) spectrum and published its first constraints on the CRE anisotropy. With respect to the previous…

High Energy Astrophysical Phenomena · Physics 2011-02-18 Giuseppe Di Bernardo , Carmelo Evoli , Daniele Gaggero , Dario Grasso , Luca Maccione , Mario Nicola Mazziotta

In this tutorial paper, we consider the problem of electromagnetic scattering by a bounded two-dimensional dielectric object, and discuss certain interesting properties of the scattered field. Using the electric field integral equation,…

Optics · Physics 2015-07-08 Uday K. Khankhoje , Kushal Shah

Several cosmic ray experiments have measured excesses in electrons and positrons, relative to standard backgrounds, for energies from ~ 10 GeV - 1 TeV. These excesses could be due to new astrophysical sources, but an explanation in which…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Spencer Chang , Lisa Goodenough

The Tibet AS$\gamma$ collaboration has reported a diffuse $\gamma$-ray emission signal from the Galactic Plane. We consider the possibility that the diffuse emission from the outer Galactic Plane at the highest energies is produced by…

High Energy Astrophysical Phenomena · Physics 2023-01-03 G. Giacinti , T. Abounnasr , A. Neronov , D. Semikoz

The recently reported positron fraction up to $\sim 350$ GeV by AMS-02 seems to have tension with the total electron/positron spectra detected by Fermi and HESS, for either pulsar or dark matter annihilation/decay scenario as the primary…

High Energy Astrophysical Phenomena · Physics 2014-05-15 Qiang Yuan , Xiao-Jun Bi

Drifts are known to play a role in galactic cosmic ray transport within the heliosphere and are a standard component of cosmic ray propagation models. However, the current paradigm of Solar Energetic Particle (SEP) propagation holds the…

Solar and Stellar Astrophysics · Physics 2013-08-30 M. S. Marsh , S. Dalla , J. Kelly , T. Laitinen

The aim of this paper is to investigate the spatial structure of the impulsive phase hard X-ray emission from solar flares. This work is motivated by the YOHKOH and the forthcoming HESSI observations. Summarizing past results, it is shown…

Astrophysics · Physics 2009-10-31 Vahe Petrosian , Timothy Q. Donaghy

An electron-positron atmosphere is inevitably created around a black hole accretion disc, the spectrum of which extends to MeV energies. Pairs created in photon-photon collisions outside the disc are blown away by soft radiation (which…

Astrophysics · Physics 2009-10-31 Andrei M. Beloborodov

We have determined the interstellar spectra of cosmic ray protons and electrons from a few MeV to ~10 GeV. These interstellar spectra are based on Voyager data and a normalization of specific galactic propagation model calculations of both…

Space Physics · Physics 2016-05-27 W. R. Webber

Extended results on the cosmic-ray electron + positron spectrum from 11 GeV to 4.8 TeV are presented based on observations with the Calorimetric Electron Telescope (CALET) on the International Space Station utilizing the data up to November…

We revisit the question of the contributions of two-photon exchange with $\Delta(1232)$ excitation to the electron-proton scattering in a hadronic model. Three improvements over the previous calculations are made, namely, correct vertex…

Nuclear Theory · Physics 2015-09-21 Hai-Qing Zhou , Shin Nan Yang

{\it Fermi} satellite has detected extra spectral components in GeV energy range in several GRBs. Those components have power-law shapes, which may contribute to also X-ray band. The limited photon statistics make it difficult to determine…

High Energy Astrophysical Phenomena · Physics 2011-11-02 Katsuaki Asano , Peter Mészáros , Kohta Murase , Susumu Inoue , Toshio Terasawa

Two years ago, the AMS collaboration released the most precise measurement of the cosmic ray positron flux. It confirms that pure secondary predictions fall below the data above 10 GeV, suggesting the presence of a primary component, e.g.…

High Energy Astrophysical Phenomena · Physics 2017-09-06 M. Boudaud , E. F. Bueno , S. Caroff , Y. Genolini , V. Poulin , V. Poireau , A. Putze , S. Rosier , P. Salati , M. Vecchi

Models for the diffuse Galactic continuum emission and synchrotron radiation show that it is difficult to reproduce observations of both of these from the same population of cosmic-ray electrons. This indicates that an important contributor…

Astrophysics · Physics 2009-10-31 A. W. Strong , I. V. Moskalenko

Theoretical spectral energy distributions were computed for a grid of hydrogen-deficient and carbon-rich model atmospheres of T(eff) in the range of 5000-6250 K and log g = 1.0 - 0.0 by the technique of opacity sampling, taking into account…

Astrophysics · Physics 2009-10-31 Ya. V. Pavlenko , L. A. Yakovina , H. W. Duerbeck
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