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Related papers: Magnetized galactic halos and velocity lags

200 papers

When the gas of a magnetized filamentary cloud obeys a polytropic equation of state, gravitational collapse of the cloud is studied using a simplified model. We concentrate on the radial distribution and restrict ourselves to the purely…

Astrophysics · Physics 2009-11-10 Mohsen Shadmehri

We examine the constraints imposed by Faraday rotation measures of extragalactic point sources on the structure of the magnetic field in the halo of our Galaxy. Guided by radio polarization observations of external spiral galaxies, we look…

Astrophysics of Galaxies · Physics 2017-03-29 Philippe Terral , Katia Ferriere

We investigate the magnetic field which is generated by turbulent motions of a weakly ionized gas. Galactic molecular clouds give us an example of such a medium. As in the Kazantsev-Kraichnan model we assume a medium to be homogeneous and a…

Astrophysics of Galaxies · Physics 2013-09-25 Ya. N. Istomin , A. M. Kiselev

We study the effect of magnetic fields on a simulated galaxy and its surrounding gaseous halo, or circumgalactic medium (CGM), within cosmological 'zoom-in' simulations of a Milky Way-mass galaxy as part of the 'Simulating the Universe with…

The dynamics of a galactic disk in a non-axisymmetric (triaxial) dark halo is studied in detail using high-resolution, numerical, hydrodynamical models. A long-lived, two-armed spiral pattern is generated for a wide range of parameters. The…

Astrophysics of Galaxies · Physics 2015-06-03 A. V. Khoperskov , M. A. Eremin , S. A. Khoperskov , M. A. Butenko , A. G. Morozov

We review the various techniques used to constrain the Galactic halo mass profile for radii > 20 kpc with particular emphasis on identifying a self-consistent halo model and resolving the apparent discrepancies present in the literature on…

Astrophysics · Physics 2007-05-23 Dennis Zaritsky

Dynamos in astrophysical disks are usually explained in terms of the standard alpha-omega mean field dynamo model where the local helicity generates a radial field component from an azimuthal field. The subsequent shearing of the radial…

Astrophysics · Physics 2015-06-24 Ethan T. Vishniac

We develop a method for recovering the global density distribution of the ancient Galactic stellar halo prior to disk formation, based on the present orbits of metal-poor stars observed in the solar neighborhood. The method relies on the…

Astrophysics · Physics 2009-10-31 Masashi Chiba , Timothy C. Beers

We examine the dependence between hydrogen total mass $M_{HI}$ and rotation speed $V_{rot}$, optical size $D_{25}$ or disc radial scale $R_0$ for two samples of late-type galaxies: a) isolated galaxy (AMIGA sample), and b) the edge-on…

Astrophysics of Galaxies · Physics 2017-07-26 Analoty V. Zasov , Natalia A. Zaitseva

We describe how a certain simple modification of general relativity, in which the local cosmological constant is allowed to depend on the space-time curvature, predicts the existence of halos of modified gravity surrounding…

General Relativity and Quantum Cosmology · Physics 2009-03-20 Kirill Krasnov , Yuri Shtanov

Motivated by the recent direct detection of cosmological gas infall, we develop an analytical model for calculating the mean density profile around an initial overdensity that later forms a dark matter halo. We account for the problem of…

Astrophysics · Physics 2009-11-07 Rennan Barkana

The evolution of large-scale magnetic fields in disk galaxies is investigated numerically. The gasdynamical simulations in a disk perturbed by spiral or bar potential are incorporated into the kinematic calculations of induction equations…

Astrophysics · Physics 2007-05-23 K. Otmianowska-Mazur , M. Chiba

Magnetic fields are dynamically important in the diffuse interstellar medium. Understanding how gravitationally bound, star-forming clouds form requires modeling of the fields in a self-consistent, supernova-driven, turbulent, magnetized,…

Astrophysics of Galaxies · Physics 2022-02-16 Juan C. Ibáñez-Mejía , Mordecai-Mark Mac Low , Ralf S. Klessen

Absorption-line measurements of the circumgalactic medium (CGM) display a highly non-uniform distribution of lower ionization state species accompanied by more widespread higher ionization state material. This suggests that the CGM is a…

Astrophysics of Galaxies · Physics 2022-03-14 Edward Buie , Evan Scannapieco , G. Mark Voit

We use three dimensional magnetohydrodynamic simulations to study the structure of the boundary layer between an accretion disc and a non-rotating, unmagnetized star. Under the assumption that cooling is efficient, we obtain a narrow but…

Astrophysics · Physics 2009-11-07 Philip J. Armitage

We have directly compared MgII halo gas kinematics to the rotation velocities derived from emission/absorption lines of the associated host galaxies. Our 0.096<z<0.148 volume-limited sample comprises 13 ~L* galaxies, with impact parameters…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 G. G. Kacprzak , C. W. Churchill , E. J. Barton , J. Cooke

A stationary self-consistent outflow of a magnetised relativistic plasma from a rotating object with an initially monopole-like magnetic field is investigated in the ideal MHD approximation under the condition $\sigma/U_0^2 >1$, where…

Astrophysics · Physics 2009-11-06 S. Bogovalov

The Hubble Space Telescope has revealed the existence of multiple, regularly spaced, and faint concentric shells around some planetary nebulae. Here we present 2(1/2)D magnetohydrodinamic numerical simulations of the effects of a solar-like…

Astrophysics · Physics 2007-05-23 Guillermo Garcia-Segura , Jose Alberto Lopez , Jose Franco

This is the third paper in a series in which we attempt to put constraints on the flattening of dark halos in disk galaxies. For this purpose we need to analyse the observed XV diagrams in edge-on galaxies to accurately measure the radial…

Astrophysics of Galaxies · Physics 2015-05-18 J. C. O'Brien , K. C. Freeman , P. C. van der Kruit

Young stellar objects/planetary nebula outflow anisotropies usually involve wind-wind interactions and magnetic collimation, but detailed structures of wind and magnetic fields inside collimation region remain undetermined. We numerically…

Plasma Physics · Physics 2019-05-21 Tao Tao , Guangyue Hu , Ruxin Li , Zhizhan Xu , Jian Zheng