English
Related papers

Related papers: Fluid Simulations of Cosmic Ray Modified Shocks

200 papers

Cosmic rays (CRs) are dynamically important for the formation and evolution of galaxies by regulating star formation and by powering galactic outflows. However, to what extent CRs regulate galaxy formation depends on the coupling strength…

Astrophysics of Galaxies · Physics 2023-12-27 Philipp Girichidis , Maria Werhahn , Christoph Pfrommer , Rüdiger Pakmor , Volker Springel

We examine diffusive shock acceleration (DSA) of the pre-exisiting as well as freshly injected populations of nonthermal, cosmic-ray (CR) particles at weak cosmological shocks. Assuming simple models for thermal leakage injection and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Hyesung Kang , Dongsu Ryu

We study the acceleration of cosmic rays by collisionless structure formation shocks with ENZO grid simulations. Data from the FERMI satellite enable the use of galaxy clusters as a testbed for particle acceleration models. Based on…

Astrophysics of Galaxies · Physics 2016-03-23 F. Vazza , M. Brueggen , D. Wittor , C. Gheller , D. Eckert , M. Stubbe

Cosmic rays (CRs) are thought to play an important role in galaxy evolution. We study their effect when coupled to other important sources of feedback, namely supernovae and stellar radiation, by including CR anisotropic diffusion and…

Astrophysics of Galaxies · Physics 2022-05-27 Marion Farcy , Joakim Rosdahl , Yohan Dubois , Jérémy Blaizot , Sergio Martin-Alvarez

There are two distinct breaks in the cosmic ray (CR) spectrum: the so-called "knee" around $3 \times 10^{15}$ eV and the so-called "ankle" around $10^{18}$ eV. Diffusive shock acceleration (DSA) at supernova remnant (SNR) shock fronts is…

High Energy Astrophysical Phenomena · Physics 2017-01-25 Chad Bustard , Ellen G. Zweibel , Cory Cotter

We perform kinetic simulations of diffusive shock acceleration (DSA) in Type Ia supernova remnants (SNRs) expanding into a uniform interstellar medium (ISM). Bohm-like diffusion assumed, and simple models for Alfvenic drift and dissipation…

High Energy Astrophysical Phenomena · Physics 2017-01-18 Hyesung Kang

The non-linear back reaction of accelerated cosmic rays at the shock fronts, leads to the formation of a smooth precursor with a length scale corresponding to the diffusive scale of the energetic particles. Past works claimed that shocklets…

Astrophysics · Physics 2007-08-13 A. Meli , P. L. Biermann , S. Dimitrakoudis

Using three-dimensional magnetohydrodynamics simulations, we show that the efficiency of cosmic-ray (CR) production at supernova remnants (SNRs) is over-predicted if it could be estimated based on proper motion measurements of H$\alpha$…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Jiro Shimoda , Tsuyoshi Inoue , Yutaka Ohira , Ryo Yamazaki , Aya Bamba , Jacco Vink

This paper presents a new resolution strategy for multi-scale streamer discharge simulations based on a second order time adaptive integration and space adaptive multiresolution. A classical fluid model is used to describe plasma…

Numerical Analysis · Mathematics 2012-04-10 Max Duarte , Zdenek Bonaventura , Marc Massot , Anne Bourdon , Stéphane Descombes , Thierry Dumont

We present the first simulations evolving resolved spectra of cosmic rays (CRs) from MeV-TeV energies (including electrons, positrons, (anti)protons, and heavier nuclei), in live kinetic-MHD galaxy simulations with star formation and…

High Energy Astrophysical Phenomena · Physics 2023-08-29 Philip F. Hopkins , Iryna S. Butsky , Georgia V. Panopoulou , Suoqing Ji , Eliot Quataert , Claude-Andre Faucher-Giguere , Dusan Keres

In this second paper in a series dedicated to characterizing shear layers via 2D hybrid (kinetic ions -- fluid electrons) simulations, we study the dynamical role of nonthermal particles (cosmic rays, CRs), either spontaneously generated or…

High Energy Astrophysical Phenomena · Physics 2026-04-15 Naixin Liang , Damiano Caprioli

We have developed a novel computer code designed to follow the evolution of cosmic-ray modified shocks, including the full momentum dependence of the particles for a realistic diffusion coefficient model. In this form the problem is…

Astrophysics · Physics 2009-10-31 Hyesung Kang , T. W. Jones , R. J. LeVeque , K. M. Shyue

Bow shocks generated from the interaction of winds from massive runaway stars with the interstellar medium have been shown to be prominent particle accelerators through recent $\gamma$-ray and radio synchrotron observations. Here, we study…

High Energy Astrophysical Phenomena · Physics 2025-10-15 Keito Watanabe , Stefanie Walch , Tim-Eric Rathjen , Jonathan Mackey , Pierre Nürnberger , Philipp Girichidis

Cosmic rays (CR) propagate through the galactic scales down to the smaller scales at which stars form. CRs are close to energy equipartition with the other components of the interstellar medium and can provide a support against gravity if…

Astrophysics of Galaxies · Physics 2019-02-13 Benoît Commerçon , Alexandre Marcowith , Yohan Dubois

Radio relics could be generated by multiple shocks induced in the turbulent intracluster medium during galaxy mergers. Kang (2021) demonstrated that the re-acceleration of cosmic ray (CR) protons via diffusive shock acceleration (DSA) by…

High Energy Astrophysical Phenomena · Physics 2021-08-05 Hyesung Kang

We carry out a suite of simulations of the evolution of cosmic-ray (CR) driven, radiatively-cooled cold clouds embedded in hot material, as found in galactic outflows. In such interactions, CRs stream towards the cloud at the Alfv\'en…

Astrophysics of Galaxies · Physics 2020-12-16 Marcus Brüggen , Evan Scannapieco

We present a numerical scheme, implemented in the cosmological adaptive mesh refinement code ENZO, to model the injection of Cosmic Ray (CR) particles at shocks, their advection and their dynamical feedback on thermal baryonic gas. We give…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 F. Vazza , M. Bruggen , C. Gheller , G. Brunetti

Cosmic ray electron (CRE) acceleration and cooling are important physical processes in astrophysics. We develop an approximative framework to treat CRE physics in the parallel smoothed particle hydrodynamics code Gadget-3. In our…

High Energy Astrophysical Phenomena · Physics 2019-12-03 Dongchao Zheng , Weitian Li , Zhenghao Zhu , Chenxi Shan , Jiajun Zhang , Linfeng Xiao , Xiaoli Lian , Dan Hu

We present a novel implementation of cosmic rays (CR) in the magneto-hydrodynamic code FLASH. CRs are described as separate fluids with different energies. CR advection, energy dependent anisotropic diffusion with respect to the magnetic…

High Energy Astrophysical Phenomena · Physics 2014-06-20 Philipp Girichidis , Thorsten Naab , Stefanie Walch , Michal Hanasz

Cosmic rays (CRs) are an integral part of the non-thermal pressure budget in the interstellar medium (ISM) and are the leading-order ionization mechanism in cold molecular clouds. We study the impacts that different microphysical CR…