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Related papers: Supernova-driven Turbulence and Magnetic Field Amp…

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When present, extended disks of neutral hydrogen around spiral galaxies show a remarkably uniform velocity dispersion of approx 6 km/s. Since stellar winds and supernovae are largely absent in such regions, neither the magnitude nor the…

Astrophysics · Physics 2009-10-30 J. A. Sellwood , S. A. Balbus

Magnetic field amplification by a fast dynamo is seen in local box simulations of SN-driven ISM turbulence, where the self-consistent emergence of large-scale fields agrees very well with its mean-field description. We accordingly derive…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-25 Detlef Elstner , Oliver Gressel

Galaxies' interstellar media (ISM) are observed to be supersonically-turbulent, but the ultimate power source that drives turbulent motion remains uncertain. The two dominant models are that the turbulence is driven by star formation…

Astrophysics of Galaxies · Physics 2016-03-23 Mark R. Krumholz , Blakesley Burkhart

The stationary accretion shock instability (SASI) plays a central role in modern simulations of the explosion phase of core-collapse supernovae (CCSNe). It may be key to realizing neutrino powered explosions, and possibly links birth…

Solar and Stellar Astrophysics · Physics 2015-06-04 E. Endeve , C. Y. Cardall , R. D. Budiardja , A. Mezzacappa , J. M. Blondin

Supernova Remnants (SNRs) shocks are believed to accelerate charged particles and to generate strong turbulence in the post-shock flow. From high-energy observations in the past decade, a magnetic field at SNR shocks largely exceeding the…

High Energy Astrophysical Phenomena · Physics 2015-06-18 F. Fraschetti

Irregular galaxies are usually smaller and less massive than their spiral, S0, and elliptical counterparts. Radio observations indicate that a magnetic field is present in irregular galaxies whose value is similar to that in spiral…

Astrophysics of Galaxies · Physics 2014-11-20 H. Siejkowski , M. Soida , K. Otmianowska-Mazur , M. Hanasz , D. J. Bomans

Numerical simulations of the multi-phase interstellar medium have been carried out, using a 3D, nonlinear, magnetohydrodynamic, shearing-box model, with random motions driven by supernova explosions. These calculations incorporate the…

Astrophysics · Physics 2009-11-10 Graeme R. Sarson , Anvar Shukurov , Aake Nordlund , Boris Gudiksen , Axel Brandenburg

We examine MHD simulations of the propagation of a strong shock wave through the interstellar two-phase medium composed of small-scale cloudlets and diffuse warm neutral medium in two-dimensional geometry. The pre-shock two-phase medium is…

Solar and Stellar Astrophysics · Physics 2010-11-30 Tsuyoshi Inoue , Ryo Yamazaki , Shu-ichiro Inutsuka

Large-scale magnetic fields in stars and galaxies are thought to arise by mean-field dynamo action due to the combined influence of both helical turbulence and shear. Those systems are also highly conducting and the turbulence therein leads…

Astrophysics of Galaxies · Physics 2019-05-22 Pallavi Bhat , Kandaswamy Subramanian , Axel Brandenburg

The origin and sustenance of large scale galactic magnetic fields has been a long standing and controversial astrophysical problem. Here an alternative to the ``standard'' $\a-\Omega$ mean field dynamo and primordial theories is pursued.…

Astrophysics · Physics 2009-10-30 Eric G. Blackman

Galactic dynamo models take as input certain parameters of the interstellar turbulence, most essentially the correlation time $\tau$, root-mean-square turbulent speed $u$, and correlation scale $l$. However, these quantities are difficult,…

Astrophysics of Galaxies · Physics 2020-08-18 Luke Chamandy , Anvar Shukurov

The diffusion of astrophysical magnetic fields in conducting fluids in the presence of turbulence depends on whether magnetic fields can change their topology via reconnection in highly conducting media. Recent progress in understanding…

Astrophysics of Galaxies · Physics 2012-12-17 R. Santos-Lima , A. Lazarian , E. M. de Gouveia Dal Pino , J. Cho

(ABBREVIATED) Understanding the formation of stars in galaxies is central to much of modern astrophysics. In this review the relation between interstellar turbulence and star formation is discussed. Supersonic turbulence can provide support…

Astrophysics · Physics 2009-09-29 Ralf S. Klessen

Magnetic fields pervade the entire Universe and affect the formation and evolution of astrophysical systems from cosmological to planetary scales. The generation and dynamical amplification of extragalactic magnetic fields through cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 F. Rincon , F. Califano , A. A. Schekochihin , F. Valentini

The role of turbulence in astrophysical environments and its interplay with magnetic fields is still highly debated. In this lecture, we will discuss this issue in the framework of dynamo processes. We will first present a very brief…

Solar and Stellar Astrophysics · Physics 2015-06-12 E. M. de Gouveia Dal Pino , R. Santos-Lima , G. Kowal , D. Falceta-Gonçalves

Nonresonant current instability was identified by Bell (2004) as an important mechanism for magnetic field amplification in supernova remnants. In this paper we focus on studying the nonlinear stage of this instability using the…

Astrophysics of Galaxies · Physics 2014-06-06 Andrey Beresnyak , Hui Li

Magnetic fields on the order of 100 $\mu$G observed in young supernova remnants cannot be amplified by shock compression alone. To investigate the amplification caused by turbulent dynamo, we perform three-dimensional MHD simulations of the…

Astrophysics of Galaxies · Physics 2022-12-28 Yue Hu , Siyao Xu , James M. Stone , Alex Lazarian

We consider a recently discovered class of instabilities, driven by cosmic ray streaming, in a variety of environments. We show that although these instabilities have been discussed primarily in the context of supernova driven interstellar…

Astrophysics of Galaxies · Physics 2014-11-20 Ellen G. Zweibel , John E. Everett

In this paper we show that the Universe is already strongly magnetized at very early epochs during cosmic evolution. Our calculations are based on the efficient amplification of weak magnetic seed fields, which are unavoidably present in…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Jacques M. Wagstaff , Robi Banerjee , Dominik Schleicher , Guenter Sigl

Mean-field dynamo theory has important applications in solar physics and galactic magnetism. We discuss some of the many turbulence effects relevant to the generation of large-scale magnetic fields in the solar convection zone. The…

Solar and Stellar Astrophysics · Physics 2023-11-23 Axel Brandenburg , Detlef Elstner , Youhei Masada , Valery Pipin