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Related papers: Cosmic ray acceleration at oblique shocks

200 papers

We present some recent developments in the theory of particle acceleration at shock fronts in the presence of dynamical reaction of the accelerated particles and self-generation of magnetic field due to streaming instability. The spectra of…

Astrophysics · Physics 2007-06-13 Pasquale Blasi , Elena Amato

When the pressure of particles accelerated at shock waves is no longer negligible compared to the kinetic pressure of the gas, the linear theory of diffusive shock acceleration breaks down. This is expected in particular when the shock…

High Energy Astrophysical Phenomena · Physics 2021-12-22 Thibault Vieu , Stefano Gabici , Vincent Tatischeff

Galactic cosmic rays (CRs) are accelerated at the forward shocks of supernova remnants (SNRs) via diffusive shock acceleration (DSA), an efficient acceleration mechanism that predicts power-law energy distributions of CRs. However,…

High Energy Astrophysical Phenomena · Physics 2021-11-24 Rebecca Diesing , Damiano Caprioli

Using a semi-analytic model of non-linear diffusive shock acceleration, we model the spectrum of cosmic ray (CR) electrons accelerated by supernova remnants (SNRs). Because electrons experience synchrotron losses in the amplified magnetic…

High Energy Astrophysical Phenomena · Physics 2019-08-21 Rebecca Diesing , Damiano Caprioli

In this work we investigate particle acceleration in supernova remnant shocks within a semi-analytical formalism which self-consistently accounts for particle acceleration, amplification of the magnetic field via streaming instability and…

High Energy Astrophysical Phenomena · Physics 2011-03-25 Damiano Caprioli

The spectra of high-energy protons and nuclei accelerated by supernova remnant shocks are calculated taking into account magnetic field amplification and Alfvenic drift both upstream and downstream of the shock for different types of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 V. S. Ptuskin , V. N. Zirakashvili , E. S. Seo

We investigate the spatial distribution of charged particles accelerated by non-relativistic oblique fast collisionless shocks using three-dimensional test-particle simulations. We find that the density of low-energy particles exhibit a…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Federico Fraschetti , Joe Giacalone

Diffusive shock acceleration is the prime candidate for efficient acceleration of cosmic rays. Galactic cosmic rays are believed to originate predominantly from this process in supernova remnant shock waves. Confinement of the cosmic rays…

High Energy Astrophysical Phenomena · Physics 2011-10-07 K. M. Schure , A. R. Bell

We investigate acceleration of cosmic rays by shocks and accretion flows in galaxy clusters. Numerical results for spectra of accelerated particles and nonthermal emission are presented. It is shown that the acceleration of protons and…

High Energy Astrophysical Phenomena · Physics 2019-05-22 V. N. Zirakashvili , V. S. Ptuskin

Cosmic-ray acceleration at non-relativistic shocks relies on scattering by turbulence that the cosmic rays drive upstream of the shock. We explore the rate of energy transfer from cosmic rays to non-resonant Bell modes and the spectral…

High Energy Astrophysical Phenomena · Physics 2021-11-17 Martin Pohl

A new numerical model of the nonlinear diffusive shock acceleration is presented. It is used for modeling of particle acceleration in supernova remnants. The model contains coupled spherically symmetric hydrodynamic equations and the…

High Energy Astrophysical Phenomena · Physics 2015-05-30 V. N. Zirakashvili , V. S. Ptuskin

We describe a semi-analytical approach to non-linear diffusive shock acceleration in the case in which nuclei other than protons are also accelerated. The structure of the shock is determined by the complex interplay of all nuclei, and in…

High Energy Astrophysical Phenomena · Physics 2010-11-10 D. Caprioli , P. Blasi , E. Amato

Most cosmic rays are thought to be accelerated by the shocks of supernova explosions of very massive stars. Here we review one quantitative proposal, which predicted the spectral slopes, bend and cutoff about the cosmic ray spectrum across…

Astrophysics · Physics 2009-11-10 Peter L. Biermann

The first-order cosmic ray acceleration at ultrarelativistic shocks is investigated using the Monte Carlo method. We apply a method of discrete particle momentum scattering as a model of particle pitch angle diffusion to reproduce highly…

Astrophysics · Physics 2007-05-23 J. Bednarz

Galactic cosmic rays (CRs) are accelerated by astrophysical shocks, primarily supernova remnants (SNRs), via diffusive shock acceleration (DSA), an efficient mechanism that predicts power-law energy distributions of CRs. However,…

High Energy Astrophysical Phenomena · Physics 2021-09-24 Rebecca Diesing , Damiano Caprioli

Diffusive shock acceleration is considered as the main mechanism for particle energization in supernova remnants, as well as in other classes of sources. The existence of some remnants that show a bilateral morphology in the X-rays and…

High Energy Astrophysical Phenomena · Physics 2019-08-07 Pierre Cristofari , Pasquale Blasi

We investigate the appearance of magnetic field amplification resulting from a cosmic ray escape current in the context of supernova remnant shock waves. The current is inversely proportional to the maximum energy of cosmic rays, and is a…

High Energy Astrophysical Phenomena · Physics 2015-06-16 K. M. Schure , A. R. Bell

We show that a purely kinetic approach to the excitation of waves by cosmic rays in the vicinity of a shock front leads to predict the appearance of a non-alfv\'enic fastly growing mode which has the same dispersion relation as that…

Astrophysics · Physics 2009-11-13 Elena Amato , Pasquale Blasi

The particle acceleration process at a shock wave, in the presence of the second-order Fermi acceleration in the turbulent medium near the shock, is discussed as an alternative explanation for the observed flat synchrotron spectra of…

Astrophysics · Physics 2007-05-23 M. Ostrowski

The theory of first order Fermi acceleration at shocks assumes that particles diffuse due to scattering off slow-moving magnetic irregularities. However, cosmic rays are closely tied to magnetic field lines, and the transport process,…

Astrophysics · Physics 2011-05-23 P. Duffy , J. G. Kirk , Y. A. Gallant , R. O. Dendy