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Related papers: Cosmic-ray driven dynamo in galactic disks

200 papers

The theory of Galactic Winds, driven by the cosmic-ray pressure gradient, is reviewed both on the magnetohydrodynamic and on the kinetic level. In this picture the magnetic field of the Galaxy above the dense gas disk is assumed to have a…

High Energy Astrophysical Phenomena · Physics 2014-11-06 Heinrich J. Völk

The macroscopic behaviour of cosmic rays in turbulent magnetic fields is discussed. An implementation of anisotropic diffusion of cosmic rays with respect to the magnetic field in a non-conservative, high-order, finite-difference…

Astrophysics · Physics 2008-11-26 A. P. Snodin , Axel Brandenburg , A. J. Mee , Anvar Shukurov

Feedback processes in galaxies dictate their structure and evolution. Baryons can be cycled through stars, which inject energy into the interstellar medium (ISM) in supernova explosions, fueling multiphase galactic winds. Cosmic rays (CRs)…

Astrophysics of Galaxies · Physics 2025-06-16 Brandon Sike , Timon Thomas , Mateusz Ruszkowski , Christoph Pfrommer , Matthias Weber

Recent years have seen many arguments for cosmic rays (CRs) as an important influence on galactic and circumgalactic (CGM) physics, star and galaxy formation. We present a pedagogical overview of state-of-the-art modeling of…

Astrophysics of Galaxies · Physics 2026-05-11 Philip F. Hopkins

We investigate the dynamical impact of cosmic rays in cosmological simulations of galaxy formation using adaptive-mesh refinement simulations of a $10^{12}$ solar mass halo. In agreement with previous work, a run with only our standard…

Astrophysics of Galaxies · Physics 2015-06-23 Munier Salem , Greg L. Bryan , Cameron Hummels

Supernovae are known to be the dominant energy source for driving turbulence in the interstellar medium. Yet, their effect on magnetic field amplification in spiral galaxies is still poorly understood. Previous analytical models, based on…

Astrophysics · Physics 2009-11-13 Oliver Gressel , Detlef Elstner , Udo Ziegler , Günther Rüdiger

We review the main observational and theoretical facts about acceleration of Galactic cosmic rays in supernova remnants, discussing the arguments in favor and against a connection between cosmic rays and supernova remnants, the so-called…

High Energy Astrophysical Phenomena · Physics 2017-08-23 Pasquale Blasi

Galactic cosmic rays are widely believed to be accelerated in expanding shock waves initiated by supernova explosions. The theory of diffusive shock acceleration of cosmic rays is now well established, but two fundamental questions remain…

Astrophysics · Physics 2008-07-25 Vincent Tatischeff

The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense…

High Energy Astrophysical Phenomena · Physics 2017-04-19 Anvar Shukurov , Andrew Snodin , Amit Seta , Paul Bushby , Toby Wood

(Abridged) Based on the rapidly increasing all-sky data of Faraday rotation measures and polarised synchrotron radiation, the Milky Way's magnetic field is now modelled with an unprecedented level of detail and complexity. We aim to…

Astrophysics of Galaxies · Physics 2015-06-17 Oliver Gressel , Detlef Elstner , Udo Ziegler

Cosmic rays fill up the entire volume of galaxies, providing an important source of heating and ionisation of the interstellar medium, and may play a significant role in the regulation of star formation and galactic evolution. Diffuse…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Troy A. Porter

In the present paper we construct maps of polarized synchrotron radio emission of a whole galaxy, based on local models of the cosmic ray (CR) driven dynamo. We perform numerical simulations of the dynamo in local Cartesian domains, with…

We present results from high-resolution hydrodynamic simulations of isolated SMC- and Milky Way-sized galaxies that include a model for feedback from galactic cosmic rays (CRs). We find that CRs are naturally able to drive winds with mass…

Astrophysics of Galaxies · Physics 2015-06-17 C. M. Booth , Oscar Agertz , Andrey V. Kravtsov , Nickolay Y. Gnedin

Galactic winds constitute a primary feedback process in the ecology and evolution of galaxies. They are ubiquitously observed and exhibit a rich phenomenology, whose origin is actively investigated both theoretically and observationally.…

High Energy Astrophysical Phenomena · Physics 2022-07-13 Sarah Recchia

We study the magnetic field evolution of an isolated spiral galaxy, using isolated Milky Way-mass galaxy formation simulations and a novel prescription for magnetohydrodynamic (MHD) supernova feedback. Our main result is that a galactic…

Astrophysics of Galaxies · Physics 2017-07-26 Iryna Butsky , Jonathan Zrake , Ji-hoon Kim , Hung-I Yang , Tom Abel

Galactic outflows influence the evolution of galaxies not only by expelling gas from their disks but also by injecting energy into the circumgalactic medium (CGM). This alters or even prevents the inflow of fresh gas onto the disk and thus…

Astrophysics of Galaxies · Physics 2025-06-04 Timon Thomas , Christoph Pfrommer , Rüdiger Pakmor

We apply a wind model, driven by combined cosmic-ray and thermal-gas pressure, to the Milky Way, and show that the observed Galactic diffuse soft X-ray emission can be better explained by a wind than by previous static gas models. We find…

Observations in polarized emission reveal the existence of large-scale coherent magnetic fields in a wide range of spiral galaxies. Radio-polarization data show that these fields are strongly inclined towards the radial direction, with…

Astrophysics · Physics 2009-11-13 Oliver Gressel , Udo Ziegler , Detlef Elstner , Günther Rüdiger

The origin and evolution of cosmic magnetic fields as well as the influence of the magnetic fields on the evolution of galaxies are unknown. Though not without challenges, the dynamo theory can explain the large-scale coherent magnetic…

Astrophysics of Galaxies · Physics 2016-02-17 F. S. Tabatabaei , T. P. K. Martinsson , J. H. Knapen , J. E. Beckman , B. Koribalski , B. G. Elmegreen

The universe is permeated by magnetic fields, with strengths ranging from a femtogauss in the voids between the filaments of galaxy clusters to several teragauss in black holes and neutron stars. The standard model behind cosmological…