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Related papers: The Galactic Dynamo and Superbubbles

200 papers

We use high resolution N-Body/SPH simulations to study the hydro-dynamical and gravitational interaction between the Large Magellanic Cloud and the Milky Way. We model the dark and hot extended halo components as well as the stellar/gaseous…

Astrophysics · Physics 2007-05-23 C. Mastropietro , B. Moore , L. Mayer , J. Stadel , J. Wadsley

Observations reveal the presence of supermassive black holes (SMBH) as early as ~700 million years after the Big Bang. Their formation path is still subject to current debate. We explore the influence of magnetic fields, which are strongly…

Astrophysics of Galaxies · Physics 2019-06-12 Philipp Grete , Muhammad A. Latif , Dominik R. G. Schleicher , Wolfram Schmidt

Combined action of helical motions of plasma (the $\alpha$ effect) and non-uniform (differential) rotation is a key dynamo mechanism of solar and galactic large-scale magnetic fields. Dynamics of magnetic helicity of small-scale fields is a…

Solar and Stellar Astrophysics · Physics 2022-09-20 N. Kleeorin , I. Rogachevskii

Magnetic fields are observed beyond the peripheries of optically detected galactic discs, while numerical models of their origin and the typical magnitudes are still absent. Previously, studies of galactic dynamo have avoided considering…

Astrophysics of Galaxies · Physics 2014-09-05 E. Mikhailov , A. Kasparova , D. Moss , R. Beck , D. Sokoloff , A. Zasov

We investigate statistically the dynamical consequences of cosmological fluxes of matter and related moments on progenitors of today's dark matter haloes. Their dynamics is described via canonical perturbation theory which accounts for two…

Astrophysics · Physics 2009-11-11 Christophe Pichon , Dominique Aubert

It is shown that the turbulent dynamo $\alpha$-effect converts magnetic helicity from the turbulent field to the mean field when the turbulence is electromagnetic while the magnetic helicity of the mean-field is transported across space…

Astrophysics · Physics 2008-11-26 Hantao Ji

We study steady, radial gas outflows from galaxies in an effort to understand the way tenuous and hot gas is transported to large distances away from galaxies. In particular, we obtain solutions for outflow problems, and study the outflow…

Astrophysics · Physics 2009-10-22 Boqi Wang

Theoretical and observational arguments suggest that there is a large amount of hot ($\sim 10^6$ K), diffuse gas residing in the Milky Way's halo, while its total mass and spatial distribution are still unclear. In this work, we present a…

Astrophysics of Galaxies · Physics 2020-05-06 Xiang-Er Fang , Fulai Guo , Ye-Fei Yuan

We investigate the impact of gas accretion in streams on the evolution of disc galaxies, using magneto-hydrodynamic simulations including advection and anisotropic diffusion of cosmic rays generated by supernovae as the only source of…

Astrophysics of Galaxies · Physics 2021-10-13 Nicolas Peschken , Michał Hanasz , Thorsten Naab , Dominik Wóltański , Artur Gawryszczak

A simple model for the dust media describing evolution of the system like spiral galaxy is considered. In contrast to previous considerations we show that the initial density fold should be quasi-one-dimensional (bar-like) instead of…

Astrophysics · Physics 2007-05-23 A. E. Filippov , A. S. Zhedanov

Absorption lines with high blue-shifted velocities are frequently found in the ultraviolet (UV) and X-ray spectra of luminous active galactic nuclei (AGNs). This implies that high-velocity winds/outflows are common in AGNs. In order to…

High Energy Astrophysical Phenomena · Physics 2021-06-23 Xiao-Hong Yang , Kamarjan Ablimit , Qi-Xiu Li

Turbulence with a large magnetic Reyonolds number, generically leads to rapidly growing magnetic noise over and above any mean field. We revisit the dynamics of this fluctuating field, in homogeneous, isotropic, helical turbulence. Assuming…

Astrophysics · Physics 2007-05-23 K. Subramanian

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

The theory of planetary dynamos and its applications to observed phenomena of planetary magnetism are outlined. It is generally accepted that convection flows driven by thermal or compositional buoyancy are the most likely source for the…

Fluid Dynamics · Physics 2009-04-14 F. H. Busse , R. D. Simitev

The diffusive paradigm for the transport of Galactic cosmic rays is central to our understanding of the origin of these high energy particles. However, it is worth recalling that the normalization, energy dependence, and spatial extent of…

High Energy Astrophysical Phenomena · Physics 2018-07-11 Carmelo Evoli , Pasquale Blasi , Giovanni Morlino , Roberto Aloisio

Magnetic fields are an elemental part of the interstellar medium in galaxies. However, their impact on gas dynamics and star formation in galaxies remains controversial. We use a suite of global magnetohydrodynamical simulations of isolated…

Astrophysics of Galaxies · Physics 2019-09-25 Bastian Körtgen , Robi Banerjee , Ralph E. Pudritz , Wolfram Schmidt

We investigate the dynamics of magnetic fields in spiral galaxies by performing 3D MHD simulations of galactic discs subject to a spiral potential. Recent hydrodynamic simulations have demonstrated the formation of inter-arm spurs as well…

Astrophysics · Physics 2009-11-13 C. L. Dobbs , D. J. Price

We present a detailed analysis of a disc galaxy forming in a high-resolution fully cosmological simulation to investigate the nature of the outer regions of discs and their relevance for the disc formation process. Specifically, we focus on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Rok Roškar , Victor P. Debattista , Alyson M. Brooks , Thomas R. Quinn , Chris B. Brook , Fabio Governato , Julianne J. Dalcanton , James Wadsley

The Galactic magnetic field plays an important role in the evolution of the Galaxy, but its small-scale behaviour is still poorly known. It is also unknown whether it permeates the halo of the Galaxy or not. By using observations of pulsars…

High Energy Astrophysical Phenomena · Physics 2020-03-09 Federico Abbate , Andrea Possenti , Caterina Tiburzi , Ewan Barr , Willem van Straten , Alessandro Ridolfi , Paulo Freire

The origin of cosmic magnetism is an issue of fundamental importance in astrophysics. We review here some of the ideas of how large scale magnetic fields in the universe, particularly in galaxies and galaxy clusters could arise. The popular…

Astrophysics · Physics 2009-06-23 Kandaswamy Subramanian