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Related papers: A new cosmic ray-driven instability

200 papers

The spatial distribution of cosmic ray (CR) particles in the interstellar medium (ISM) is of major importance in radio astronomy, where its knowledge is essential for the interpretation of observations, and in theoretical astrophysics,…

Astrophysics of Galaxies · Physics 2023-06-28 Devika Tharakkal , Andrew P. Snodin , Graeme R. Sarson , Anvar Shukurov

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 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

Cosmic ray (CR) electrons are key tracers of non-thermal processes in galaxies, yet their spectra are often modelled under the untested assumption of steady state between injection and cooling. In this work, we present a time-dependent…

Latest precise cosmic-ray (CR) measurements and present gamma-ray observations have started challenging our understanding of CR transport and interaction in the Galaxy. Moreover, because the density of CRs is similar to the density of the…

Collisionless plasma shocks are efficient sources of non-thermal particle acceleration in space and astrophysical systems. We use hybrid (kinetic ions -- fluid electrons) simulations to examine the non-linear feedback of the self-generated…

High Energy Astrophysical Phenomena · Physics 2020-12-16 Colby C. Haggerty , Damiano Caprioli

We study transport of GeV cosmic rays (CRs) in a set of high-resolution TIGRESS magnetohydrodynamic simulations of the star-forming interstellar medium (ISM). Our local disk patch models sample a wide range of gas surface densities,…

Astrophysics of Galaxies · Physics 2025-09-04 Ronan Hix , Lucia Armillotta , Eve Ostriker , Chang-Goo Kim

We investigate the streaming and thermal instabilities of the electron-ion plasma with homogeneous cold cosmic rays drifting perpendicular to the background magnetic field in the multi-fluid approach. One-dimensional perturbations along the…

Astrophysics of Galaxies · Physics 2012-03-27 Anatoly K. Nekrasov , Mohsen Shadmehri

Under nonuniform convection, the distribution of diffusive particles can exhibit dipole and quadrupole anisotropy induced by the fluid inertial and shear force, respectively. These convection-related anisotropies, unlike the Compton-Getting…

High Energy Astrophysical Phenomena · Physics 2022-10-26 Yiran Zhang , Siming Liu , Dejin Wu

Parker instability arises from the presence of magnetic fields in a plasma in a gravitational field such as the interstellar medium (ISM), wherein the magnetic buoyant pressure expels the gas and causes the gas to move along the field…

High Energy Astrophysical Phenomena · Physics 2011-09-07 Chih-Yueh Wang , Ying-Yi Lo , Chung-Ming Ko

We aim to elucidate cosmic ray (CR) propagation in the weakly ionized environments of supernova remnants (SNRs) basing our analysis on the cosmic ray cloud (CRC) model developed by \citet{2013ApJ...768...73M} and…

High Energy Astrophysical Phenomena · Physics 2020-01-15 L. Brahimi , A. Marcowith , V. S. Ptuskin

We study the heating of the cool cores in galaxy clusters by cosmic-rays (CRs) accelerated by the central active galactic nuclei (AGNs). We especially focus on the stability of the heating. The CRs stream with Alfv\'en waves in the…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Yutaka Fujita , Sota Kimura , Yutaka Ohira

Galactic cosmic rays are a ubiquitous source of ionisation of the interstellar gas, competing with UV and X-ray photons as well as natural radioactivity in determining the fractional abundance of electrons, ions and charged dust grains in…

High Energy Astrophysical Phenomena · Physics 2018-06-27 Marco Padovani , Alexei V. Ivlev , Daniele Galli , Paola Caselli

The thermal plasma of galaxy clusters lost most of its information on how structure formation proceeded as a result of dissipative processes. In contrast, non-equilibrium distributions of cosmic rays (CR) preserve the information about…

Astrophysics · Physics 2009-11-13 Christoph Pfrommer , Torsten A. Ensslin , Volker Springel

We present a linear perturbation analysis of the magnetorotational instability in the presence of the cosmic rays. Dynamical effects of the cosmic rays are considered by a fluid description and the diffusion of cosmic rays is only along the…

Astrophysics of Galaxies · Physics 2015-05-30 Fazeleh Khajenabi

Cosmic ray acceleration in turbulent interstellar medium is considered. Turbulence is treated as ensemble of moving magnetic traps. We derive equations for particle momentum distribution function that describes acceleration of particles in…

Astrophysics · Physics 2007-05-23 V. N. Zirakashvili

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

Core-collapse supernovae produce fast shocks which expand into the dense circumstellar medium (CSM) of the stellar progenitor. Cosmic rays (CRs) accelerated at these shocks can induce the growth of electromagnetic fluctuations in the…

High Energy Astrophysical Phenomena · Physics 2019-10-03 V. Dwarkadas , A. Marcowith , M. Renaud , V. Tatischeff , G. Giacinti

Large-scale coherent magnetic fields observed in the nearby galaxies are thought to originate by a mean-field dynamo. This is governed via the turbulent electromotive force (EMF, $\overline{\mathcal{E}} $) generated by the helical…

Astrophysics of Galaxies · Physics 2020-11-18 Abhijit B. Bendre , Detlef Elstner , Oliver Gressel

We explore the impact of diffusive cosmic rays (CRs) on the evolution of the interstellar medium (ISM) under varying assumptions of supernova explosion environment. In practice, we systematically vary the relative fractions of supernovae…

Astrophysics of Galaxies · Physics 2022-12-28 Christine M. Simpson , Rüdiger Pakmor , Christoph Pfrommer , Simon C. O. Glover , Rowan Smith