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Related papers: Cosmic-ray driven dynamo in galactic disks

200 papers

Context. The diffusive shock acceleration mechanism has been widely accepted as the acceleration mechanism for galactic cosmic rays. While self-consistent hybrid simulations have shown how power-law spectra are produced, detailed…

High Energy Astrophysical Phenomena · Physics 2015-06-04 M. Wolff , R. C. Tautz

Magnetic fields grow quickly even at early cosmological times, suggesting the action of a small-scale dynamo (SSD) in the interstellar medium of galaxies. Many studies have focused on idealized turbulent driving of the SSD. Here we simulate…

Astrophysics of Galaxies · Physics 2021-04-07 Frederick A. Gent , Mordecai-Mark Mac Low , Maarit J. Kapyla , Nishant K. Singh

Magnetic fields are ubiquitous in the Universe. Extragalactic disks, halos and clusters have consistently been shown, via diffuse radio-synchrotron emission and Faraday rotation measurements, to exhibit magnetic field strengths ranging from…

Advances in instrumentation have recently extended detailed measurements of gas kinematics to large samples of high-redshift galaxies. Relative to most nearby, thin disk galaxies, in which gas rotation accurately traces the gravitational…

Cosmic rays (CRs) are an important component in the interstellar medium (ISM), but their effect on the dynamics of the disk-halo interface (< 10 kpc from the disk) is still unclear. We study the influence of CRs on the gas above the disk…

Cosmic ray pressure gradients transfer energy and momentum to extraplanar gas in disk galaxies, potentially driving significant mass loss as galactic winds. This may be particularly important for launching high-velocity outflows of "cool"…

Astrophysics of Galaxies · Physics 2018-02-28 S. Alwin Mao , Eve C. Ostriker

The magnetic fields of our Milky Way galaxy are the main agent for cosmic rays to transport. In the last decade, much new knowledge has been gained from measurements of the Galactic magnetic fields. In the Galactic disk, from the RMs of a…

Astrophysics of Galaxies · Physics 2010-11-11 J. L. Han

It is widely believe that galactic cosmic rays are originated in supernova remnants (SNRs) where they are accelerated by diffusive shock acceleration process at supernova blast waves driven by expanding SNRs. In recent theoretical…

High Energy Astrophysical Phenomena · Physics 2017-08-02 Prabir Banik , Arunava Bhadra

We give a review of cosmic ray propagation models. It is shown that the development of the theory of cosmic ray origin leads inevitably to the conclusion that cosmic ray propagation in the Galaxy is determined by effective particle…

High Energy Astrophysical Phenomena · Physics 2009-05-20 V. Dogiel , D. Breitschwerdt

We carried out global three-dimensional magneto-hydrodynamic simulations of dynamo activities in galactic gaseous disks without assuming equatorial symmetry. Numerical results indicate the growth of azimuthal magnetic fields non-symmetric…

Astrophysics of Galaxies · Physics 2015-06-12 Mami Machida , Kenji E. Nakamura , Takahiro Kudoh , Takuya Akahori , Sofue Yoshiaki , Ryoji Matsumoto

By performing a global magnetohydrodynamical (MHD) simulation for the Milky Way with an axisymmetric gravitational potential, we propose that spatially dependent amplification of magnetic fields possibly explains the observed noncircular…

Astrophysics of Galaxies · Physics 2017-02-22 Takeru K. Suzuki , Yasuo Fukui , Kazufumi Torii , Mami Machida , Ryoji Matsumoto , Kensuke Kakiuchi

Arguably the main challenge of galactic magnetism studies is to explain how the interstellar medium of galaxies reaches energetic equipartition despite the extremely weak cosmic primordial magnetic fields that are originally predicted to…

Astrophysics of Galaxies · Physics 2018-06-20 Sergio Martin-Alvarez , Julien Devriendt , Adrianne Slyz , Romain Teyssier

Multi-wavelength observations from radio to soft X-ray bands of large-scale galactic spiral structures offer synthesized and comprehensive views of nearby disk galaxies. In the presence of a massive dark-matter halo, the density-wave…

Astrophysics · Physics 2009-11-10 Yu-Qing Lou , Zhuhui Fan

We study the cosmic evolution of the magnetic fields of a large sample of spiral galaxies in a cosmologically representative volume by employing a semi-analytic galaxy formation model and numerical dynamo solver in tandem. We start by…

Astrophysics of Galaxies · Physics 2019-01-03 Luiz Felippe S. Rodrigues , Luke Chamandy , Anvar Shukurov , Carlton M. Baugh , A. Russ Taylor

We review progress in high-energy cosmic ray physics focusing on recent experimental results and models developed for their interpretation. Emphasis is put on the propagation of charged cosmic rays, covering the whole range from $\sim…

High Energy Astrophysical Phenomena · Physics 2020-01-16 M. Kachelriess , D. V. Semikoz

Radio, X-ray and infrared observations of the inner few hundred pc of the Galactic center have highlighted two characteristics to the ISM. The cosmic ray ionization rate derived from molecular ions such as H$^+_3$, is at least two to three…

Astrophysics of Galaxies · Physics 2019-09-25 F. Yusef-Zadeh , M. Wardle

It is well known that cosmic rays (CRs) contribute significantly to the pressure of the interstellar medium in our own Galaxy, suggesting that they may play an important role in regulating star formation during the formation and evolution…

Astrophysics · Physics 2007-05-23 Christoph Pfrommer , Volker Springel , Martin Jubelgas , Torsten A. Ensslin

We propose that nearly every accelerated CR was part of the parallel current that maintains all force-free (f-f) magnetic fields. Charged particles are accelerated by the E-parallel (to the magnetic filed B) produced by reconnection. The…

Astrophysics · Physics 2015-06-24 Stirling A. Colgate , Hui Li

We demonstrate that cosmic rays form filamentary structures in the precursors of supernova remnant shocks due to their self-generated magnetic fields. The cosmic-ray filamentation results in the growth of a long wavelength instability, and…

High Energy Astrophysical Phenomena · Physics 2015-05-30 B. Reville , A. R. Bell

This is the fourth in a series of companion papers showing that, when an efficient dynamo can be maintained by accretion disks around supermassive black holes in Active Galactic Nuclei (AGNs), it will lead to the formation of a powerful,…

High Energy Astrophysical Phenomena · Physics 2019-11-06 T. Kenneth Fowler , Hui Li , Richard Anantua