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We present a semi-analytical kinetic calculation of the process of non-linear diffusive shock acceleration (NLDSA) which includes the magnetic field amplification due to cosmic ray induced streaming instability, the dynamical reaction of…

Astrophysics · Physics 2009-11-13 D. Caprioli , P. Blasi , E. Amato , M. Vietri

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

Efficient acceleration of cosmic rays (via the mechanism of diffusive shock acceleration) requires turbulent, amplified magnetic fields in the shock's upstream region. We present results of multidimensional particle-in-cell simulations…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Thomas Stroman , Martin Pohl , Jacek Niemiec

Observations of non-thermal emission from several supernova remnants suggest that magnetic fields close to the blastwave are much stronger than would be naively expected from simple shock compression of the field permeating the interstellar…

High Energy Astrophysical Phenomena · Physics 2015-06-22 T. P. Downes , L. O'C. Drury

This research was motivated by the recent observations indicating very strong magnetic fields at some supernova remnant shocks, which suggests in-situ generation of magnetic turbulence. The dissertation presents a numerical model of…

High Energy Astrophysical Phenomena · Physics 2009-04-27 Andrey Vladimirov

If highly efficient, cosmic ray production can have a significant effect on the X-ray emission from SNRs as well as their dynamical evolution. Using hydrodynamical simulations including diffusive shock acceleration, we produce spectra for…

We have performed extensive two-dimensional magnetohydrodynamic simulations to study the amplification of magnetic fields when a supernova blast wave propagates into a turbulent interstellar plasma. The blast wave is driven by injecting…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Fan Guo , Shengtai Li , Hui Li , Joe Giacalone , J. R. Jokipii , David Li

Via amplification by turbulent dynamo, magnetic fields can be potentially important for the formation of the first stars. To examine the dynamo behavior during the gravitational collapse of primordial gas, we extend the theory of nonlinear…

Solar and Stellar Astrophysics · Physics 2020-08-26 Siyao Xu , Alex Lazarian

We propose a model for Diffusive Shock Acceleration (DSA) in which stochastic magnetic fields in the shock precursor are generated through purely fluid mechanisms of a so-called small-scale dynamo. This contrasts with previous DSA models…

High Energy Astrophysical Phenomena · Physics 2015-05-14 A. Beresnyak , T. W. Jones , A. Lazarian

We investigate the influence of magnetic field amplification on the core-collapse supernovae in highly magnetized progenitors through three-dimensional simulations. By considering rotating models, we observe a strong correlation between the…

High Energy Astrophysical Phenomena · Physics 2023-12-22 Jin Matsumoto , Tomoya Takiwaki , Kei Kotake

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

We review here some magnetic phenomena in astrophysical particle accelerators associated with collisionless shocks in supernova remnants, radio galaxies and clusters of galaxies. A specific feature is that the accelerated particles can play…

High Energy Astrophysical Phenomena · Physics 2012-05-09 Andrei M. Bykov , Donald C. Ellison , Matthieu Renaud

We investigate shock acceleration in a realistic astrophysical environment with density inhomogeneities. The turbulence induced by the interaction of the shock precursor with upstream density fluctuations amplifies both upstream and…

High Energy Astrophysical Phenomena · Physics 2022-02-02 Siyao Xu , Alex Lazarian

Turbulent dynamo field amplification has often been invoked to explain the strong field strengths in thin rims in supernova shocks ($\sim 100 \, \mu$G) and in radio relics in galaxy clusters ($\sim \mu$G). We present high resolution MHD…

High Energy Astrophysical Phenomena · Physics 2016-10-13 Suoqing Ji , S. Peng Oh , Mateusz Ruszkowski , Maxim Markevitch

Based on the new findings on the turbulent dynamo in \citet{XL16}, we examine the magnetic field amplification in the context of supernova remnants. Due to the strong ion-neutral collisional damping in the weakly-ionized interstellar…

High Energy Astrophysical Phenomena · Physics 2017-12-13 Siyao Xu , Alex Lazarian

We examine the effects of streaming cosmic rays upstream of a strong, parallel collisionless shock. We include explicitly the inertia of the cosmic rays in our analysis, which was neglected in previous work. For parameters relevant to the…

High Energy Astrophysical Phenomena · Physics 2012-06-20 E. J. Greenfield , J. R. Jokipii , J. Giacalone

We are concerned with large scale magnetic field dynamo generation and propagation of magnetic fronts in turbulent electrically conducting fluids. An effective equation for the large scale magnetic field is developed here that takes into…

Astrophysics · Physics 2009-11-06 Sergei Fedotov , Alexey Ivanov , Andrey Zubarev

Radio continuum observations allow to reveal the magnetic field structure in the disk and halo of nearby spiral galaxies, their magnetic field strength and vertical scale heights. The spiral galaxies studied so far show a similar magnetic…

Astrophysics of Galaxies · Physics 2014-01-08 Marita Krause

Based on the magnetorotational model of a supernova explosion with core collapse, we investigate the significant processes of neutrino heating of the supernova shock. These processes should be taken into account in self-consistent modeling,…

Astrophysics · Physics 2007-05-23 A. A. Gvozdev , I. S. Ognev

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
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