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Related papers: Cosmic ray acceleration at oblique shocks

200 papers

Cosmic rays that escape their acceleration site interact with the ambient medium and produce gamma rays as the result of inelastic proton-proton collisions. The detection of such diffuse emission may reveal the presence of an accelerator of…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Lara Nava , Stefano Gabici

We use 2D and 3D hybrid (kinetic ions - fluid electrons) simulations to investigate particle acceleration and magnetic field amplification at non-relativistic astrophysical shocks. We show that diffusive shock acceleration operates for…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Damiano Caprioli , Anatoly Spitkovsky

Data obtained in the ATIC-2 (Advanced Thin Ionization Calorimeter), CREAM (Cosmic Ray Energetics and Mass)) and PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) experiments suggest that elemental interstellar…

High Energy Astrophysical Phenomena · Physics 2015-06-12 V. S. Ptuskin , V. N. Zirakashvili , E. S. Seo

We show that the large-scale cosmic ray anisotropy at ~10 TeV can be explained by a modified Compton-Getting effect in the magnetized flow field of old supernova remnants. This approach suggests an optimum energy scale for detecting the…

High Energy Astrophysical Phenomena · Physics 2015-06-05 P. L. Biermann , J. K. Becker , E. -S. Seo , M. Mandelartz

We study in detail the effect of different particle release times from sources on the cosmic-ray (CR) spectrum below $10^{15}eV$ in the Galaxy. We discuss different possible forms of particle injection such as burst-like injection,…

Astrophysics · Physics 2008-11-26 Satyendra Thoudam

Spectrum and chemical composition of cosmic rays accelerated in supernova remnants are studied on a basis of kinetic approach. The cosmic ray transport equation with the Bohm diffusion coefficient has been numerically solved…

Astrophysics · Physics 2008-02-03 E. G. Berezhko , G. F. Krymsky , V. K. Yelshin , L. T. Ksenofontov

We model the diffusive shock acceleration of particles in a system of two colliding shock waves and present a method to solve the time-dependent problem analytically in the test-particle approximation and high energy limit. In particular,…

High Energy Astrophysical Phenomena · Physics 2020-05-06 Thibault Vieu , Stefano Gabici , Vincent Tatischeff

We discuss the recent developments in the theory of diffusive shock acceleration (DSA) by using both first-principle kinetic plasma simulations and analytical theory based on the solution of the convection/diffusion equation. In particular,…

High Energy Astrophysical Phenomena · Physics 2019-09-16 Damiano Caprioli , Colby C. Haggerty

We have developed a numerical simulation code that treats the transport and acceleration of charged particles crossing an idealized oblique, non-relativistic shock within the framework of pitch angle transport using a finite-difference…

Astrophysics · Physics 2009-10-31 D. Ruffolo

Recent measurements of cosmic-ray spectra of several individual nuclear species by the CREAM, TRACER, and ATIC experiments indicate a change in the spectral index of the power laws at TeV energies. Possible explanations among others include…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Satyendra Thoudam , Jörg R. Hörandel

Cosmic ray nuclei fluxes are expected to be measured with high precision in the near future. For instance, high quality data on the antiproton component could give important clues about the nature of the astronomical dark matter. A very…

Astrophysics · Physics 2008-11-26 D. Maurin , F. Donato , R. Taillet , P. Salati

The ratio of the fluxes of secondary and primary nuclei in cosmic rays has long been used as an indicator of the grammage traversed in the journey of cosmic ray particles throughout the Galaxy. The basic idea is that primary particles are…

High Energy Astrophysical Phenomena · Physics 2017-08-09 Pasquale Blasi

First-order Fermi acceleration processes at ultrarelativistic shocks are studied with Monte Carlo simulations. The accelerated particle spectra are obtained by integrating the exact particle trajectories in a turbulent magnetic field near…

Astrophysics · Physics 2009-11-13 Jacek Niemiec

In this paper, we study the anisotropy of cosmic acceleration by dividing the Union2 Type Ia supernova dataset into 12 subsets according to their positions in Galactic coordinate system. In each region, we derive the deceleration parameter…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-17 W. Zhao , P. X. Wu , Y. Zhang

The spectrum of cosmic rays (CRs) is affected by their escape from an acceleration site. This may have been observed not only in the gamma-ray spectrum of young supernova remnants (SNRs) such as RX J1713.7-3946, but also in the spectrum of…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Yutaka Ohira , Kohta Murase , Ryo Yamazaki

We develop a theory to account for the cosmic ray spectrum between 1 GeV and 10^4 GeV following the earlier papers of this series. We use the basic concept that the cosmic ray particles are accelerated in a supernova shock that travels…

Astrophysics · Physics 2007-05-23 Peter L. Biermann , Richard G. Strom

Shock waves associated with shell type supernova remnants are considered to be possible sites of cosmic ray acceleration. Since shocks are capable of accelerating electrons in addition to protons one anticipates both species to contribute…

Astrophysics · Physics 2011-05-23 A. Mastichiadis

These notes present the fundamentals of Fermi acceleration at shocks, with a special attention to the role that supernova remnants have in producing Galactic cosmic rays. Then, the recent discoveries in the theory of diffusive shock…

High Energy Astrophysical Phenomena · Physics 2023-10-09 Damiano Caprioli

Recent cosmic ray (CR) experiments discovered that the CR spectra experience a remarkable hardening for rigidity above several hundred GV. We propose that this is caused by the superposition of the CR energy spectra of many sources that…

High Energy Astrophysical Phenomena · Physics 2011-09-08 Qiang Yuan , Bing Zhang , Xiao-Jun Bi

The dependence of the cosmic ray intensity on Galactocentric distance is known to be much less rapid than that to be thought-to-be sources: supernova remnants. This is an old problem ('the radial gradient problem') which has led to a number…

Astrophysics of Galaxies · Physics 2015-12-23 Anatoly Erlykin , Arnold Wolfendale , Vladimir Dogiel