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We present recent developments of global galactic-scale numerical models of the Cosmic Ray (CR) driven dynamo, which was originally proposed by Parker (1992). We conduct a series of direct CR+MHD numerical simulations of the dynamics of the…

Astrophysics of Galaxies · Physics 2015-05-27 Michał Hanasz , Dominik Wóltański , Kacper Kowalik , Hanna Kotarba

We present new developments on the Cosmic--Ray driven, galactic dynamo, modeled by means of direct, resistive CR--MHD simulations, performed with ZEUS and PIERNIK codes. The dynamo action, leading to the amplification of large--scale…

We study the global evolution of the magnetic field and interstellar medium (ISM) of the barred and ringed galaxies in the presence of non-axisymmetric components of the potential, i.e. the bar and/or the oval perturbations. The…

Astrophysics of Galaxies · Physics 2015-05-20 K. Kulpa-Dybeł , K. Otmianowska-Mazur , B. Kulesza-Żydzik , G. Kowal , D. Wóltański , M. Hanasz , K. Kowalik

We present a parameter study of the magnetohydrodynamical dynamo driven by cosmic rays in the interstellar medium (ISM) focusing on the efficiency of magnetic field amplification and the issue of energy equipartition between magnetic,…

Astrophysics · Physics 2015-05-13 Michał Hanasz , Katarzyna Otmianowska-Mazur , Grzegorz Kowal , Harald Lesch

We report first results of first global galactic-scale CR-MHD simulations of cosmic-ray-driven dynamo. We investigate the dynamics of magnetized interstellar medium (ISM), which is dynamically coupled with the cosmic-ray (CR) gas. We assume…

Astrophysics of Galaxies · Physics 2009-11-05 Michał Hanasz , Dominik Wóltański , Kacper Kowalik

We present three-dimensional global numerical simulations of the cosmic-ray (CR) driven dynamo in barred galaxies. We study the evolution of the interstellar medium of the barred galaxy in the presence of non-axisymmetric component of the…

Astrophysics of Galaxies · Physics 2011-06-02 K. Kulpa-Dybeł , K. Otmianowska-Mazur , B. Kulesza-Żydzik , G. Kowal , M. Hanasz , D. Wóltański , K. Kowalik

Energetic nonthermal particles (cosmic rays, CRs) are accelerated in supernova remnants, relativistic jets and other astrophysical objects. The CR energy density is typically comparable with that of the thermal components and magnetic…

High Energy Astrophysical Phenomena · Physics 2015-06-15 A. M. Bykov , A. Brandenburg , M. A. Malkov , S. M. Osipov

We conduct global galactic--scale magnetohydrodynamical (MHD) simulations of the cosmic--ray driven dynamo. We assume that exploding stars deposit small--scale, randomly oriented, dipolar magnetic fields into the differentially rotating…

Astrophysics of Galaxies · Physics 2009-11-13 Michał Hanasz , Dominik Wóltański , Kacper Kowalik , Rafał Pawłaszek

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 investigate the cosmic ray driven dynamo in the interstellar medium of irregular galaxy. The observations (Chyzy et al. 2000, 2003) show that the magnetic field in irregular galaxies is present and its value reaches the same level as in…

High Energy Astrophysical Phenomena · Physics 2009-11-13 Hubert Siejkowski , Marian Soida , Katarzyna Otmianowska-Mazur , Michał Hanasz , Dominik Bomans

(Abridged) X-ray observations of synchrotron rims in supernova remnant (SNR) shocks show evidence of strong magnetic field amplification (a factor of ~100 between the upstream and downstream medium). This amplification may be due to plasma…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Mario A. Riquelme , Anatoly Spitkovsky

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

We analyse the results of recent measurements of nonthermal emission from individual supernova remnants (SNRs) and their correspondence to the nonlinear kinetic theory of cosmic ray (CR) acceleration in SNRs. It is shown that the theory…

Astrophysics · Physics 2008-11-26 E. G. Berezhko

When a magnetised, thermal plasma containing a shock wave efficiently accelerates Cosmic Rays (CR) a reaction is exerted on the fluid structure. The simplest description of this process involves three conservation equations for the…

Astrophysics · Physics 2007-05-23 P. Duffy , L. O'C. Drury , H. J. Voelk

We analyse the transport of cosmic rays (CR) in magnetic fields that are structured on scales greater than the CR Larmor radius. We solve the Vlasov-Fokker-Planck (VFP) equation for various mixes of mirroring and small-angle scattering and…

High Energy Astrophysical Phenomena · Physics 2025-04-09 A. R. Bell , J. H. Matthews , A. M. Taylor , G. Giacinti

We show that the energy required to turbulently amplify magnetic field during cosmic ray (CR) acceleration by shocks extracts energy from the CR and steepens the CR energy spectrum.

High Energy Astrophysical Phenomena · Physics 2019-07-31 Anthony Bell , James Matthews , Katherine Blundell

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

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

Low-mass galaxies radio observations show in many cases surprisingly high levels of magnetic field. The mass and kinematics of such objects do not favour the development of effective large-scale dynamo action. We attempted to check if the…

Astrophysics of Galaxies · Physics 2018-03-14 Hubert Siejkowski , Marian Soida , Krzysztof T. Chyzy

Cosmic rays (CRs) and magnetic fields may be dynamically important in driving large-scale galactic outflows from rapidly star-forming galaxies. We construct two-dimensional axisymmetric models of the local starburst and super-wind galaxy…

Astrophysics of Galaxies · Physics 2020-04-29 Benjamin J. Buckman , Tim Linden , Todd A. Thompson
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