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We calculate spectra of escaping cosmic rays (CRs) accelerated at shocks produced by expanding Galactic superbubbles powered by multiple supernovae producing a continuous energy outflow in star-forming galaxies. We solve the generalized…

High Energy Astrophysical Phenomena · Physics 2020-01-28 Zhaowei Zhang , Kohta Murase , Peter Mészáros

We have performed magnetohydrodynamical simulations to study the amplification of magnetic fields in the precursors of shock waves. Strong magnetic fields are required in the precursors of the strong shocks that occur in supernova remnants.…

High Energy Astrophysical Phenomena · Physics 2015-06-17 M. Bruggen

Cosmic rays passing through large astrospheres can be efficiently cooled inside these "cavities" in the interstellar medium. Moreover, the energy spectra of these energetic particles are already modulated in front of the astrospherical bow…

Cosmic ray acceleration by shocks related with Slipping Interaction Regions (SIRs) in the Galactic Wind is considered. SIRs are similar to Solar Wind Corotating Interaction Regions. The spiral structure of our Galaxy results in a strong…

Astrophysics · Physics 2009-11-10 H. J. Voelk , V. N. Zirakashvili

Particles are accelerated to very high, non-thermal energies in space, solar, and astrophysical plasma environments. In cosmic ray physics, the "Hillas limit" is often used as a rough estimate (or the necessary condition) of the maximum…

High Energy Astrophysical Phenomena · Physics 2024-12-03 Mitsuo Oka , Kazuo Makishima , Toshio Terasawa

The origin of cosmic rays (CRs) has puzzled scientists since the pioneering discovery by Victor Hess in 1912. In the last decade, however, modern supercomputers have opened a new window on the processes regulating astrophysical…

High Energy Astrophysical Phenomena · Physics 2015-11-27 Damiano Caprioli

Highly relativistic jets from merger and accretion induced collapse of compact stellar objects, which may produce the cosmological gamma ray bursts (GRBs), are also very efficient and powerful cosmic ray accelerators. The expected…

Astrophysics · Physics 2007-05-23 Arnon Dar

In this paper intergalatic electromagnetic cascades are used as a probe of cosmic ray sources. This is achieved as follows. In extragalactic space cosmic rays initiate electromagnetic cascades in which gamma-ray and neutrino emission…

High Energy Astrophysical Phenomena · Physics 2022-12-01 Anna Uryson

Astrophysical media are turbulent and therefore reconnection should be treated in the presence of pre-existing turbulence. We consider the model of fast magnetic reconnection in Lazarian & Vishniac (1999) which predicts that the rate of…

Astrophysics of Galaxies · Physics 2015-06-05 A. Lazarian , G. Kowal , E. Gouveia dal Pino , E. Vishniac

We investigate the shock acceleration of particles in massive galaxy mergers or collisions, and show that cosmic rays (CRs) can be accelerated up to the second knee energy ~0.1-1 EeV and possibly beyond, with a hard spectral index Gamma ~…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Kazumi Kashiyama , Peter Mészáros

We give a short review of processes of stochastic acceleration in the Galaxy. We discuss: how to estimate correctly the number of accelerated particles, and at which condition the stochastic mechanism is able to generate power-law…

High Energy Astrophysical Phenomena · Physics 2017-01-20 V. A. Dogiel , K. S. Cheng , D. O. Chernyshov , A. D. Erlykin , C. -M. Ko , A. W. Wolfendale

The highest energy cosmic rays could be produced by drifts in magnetized, cylindrically collimated, sheared jets of powerful active galaxies (i.e. FR II radiogalaxies; radio loud quasars and high power BL Lacs). We show that in such…

Astrophysics · Physics 2007-06-20 Rachid Ouyed , Guenter Sigl , Maxim Lyutikov

Cosmic rays (CRs) are an important energy source in the circum-galactic medium (CGM) that impact the multi-phase gas structure and dynamics. We perform two-dimensional CR-magnetohydrodynamic simulations to investigate the role of CRs in…

Astrophysics of Galaxies · Physics 2022-06-14 Xiaoshan Huang , Yan-fei Jiang , Shane W. Davis

Galactic cosmic ray (CR) acceleration to the knee in the spectrum at a few PeV is only possible if the magnetic field ahead of a supernova remnant (SNR) shock is strongly amplified by CR escaping the SNR. A model formulated in terms of the…

High Energy Astrophysical Phenomena · Physics 2015-06-12 AR Bell , KM Schure , B Reville , G Giacinti

The acceleration of energetic particle transport in high amplitude magnetosonic and Alfvenic turbulence is considered using the method of Monte Carlo particle simulations, involving integration of particle equations of motion. We derive the…

Astrophysics · Physics 2009-09-25 G. Michalek , M. Ostrowski , R. Schlickeiser

The sharp magnetic discontinuities which naturally appear in solar magnetic flux tubes driven by turbulent photospheric motions are associated with intense currents. \citet{Par83} proposed that these currents can become unstable to a…

Astrophysics · Physics 2009-11-10 Kaspar Arzner , Loukas Vlahos

Cosmic rays (CRs) may be used to infer properties of intervening cosmic magnetic fields. Conversely, understanding the effects of magnetic fields on the propagation of high-energy CRs is crucial to elucidate their origin. In the present…

High Energy Astrophysical Phenomena · Physics 2018-11-08 R. Alves Batista , E. M. de Gouveia Dal Pino , K. Dolag , S. Hussain

It has been suggested that cosmological gamma-ray bursts (GRBs) can produce the observed flux of cosmic rays at the highest energies. However, recent studies of GRBs indicate that their redshift distribution likely follows that of the…

Astrophysics · Physics 2009-10-31 S. T. Scully , F. W. Stecker

We constrain high-energy neutrino fluxes with the observed cosmic ray and gamma ray fluxes, include flavor oscillations and propagation through Earth, and show that blazars could possibly be detected by cubic-kilometer neutrino telescopes.

Astrophysics · Physics 2007-05-23 Christian Hettlage , Karl Mannheim

The maximum cosmic ray energy achievable by acceleration by a relativistic blast wave is derived. It is shown that forward shocks from long GRB in the interstellar medium are powerful enough to produce the Galactic cosmic-ray component up…

High Energy Astrophysical Phenomena · Physics 2015-05-27 David Eichler , Martin Pohl
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