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We describe a first attempt to derive properties of the regular and turbulent Galactic magnetic field from multi-frequency polarimetric observations of the diffuse Galactic synchrotron background. A single-cell-size model of the thin…

Astrophysics · Physics 2009-11-10 M. Haverkorn , P. Katgert , A. G. de Bruyn

We study numerically large-scale magnetic field evolution and its enhancement in gaseous disks of spiral galaxies. We consider a set of models with the various spiral pattern parameters and the initial magnetic field strength with taking…

Astrophysics of Galaxies · Physics 2018-01-31 S. A. Khoperskov , S. S. Khrapov

A new, much improved model of the Galactic Magnetic Field (GMF) is presented. We use the WMAP7 Galactic Synchrotron Emission map and more than forty thousand extragalactic rotation measures to constrain the parameters of the GMF model,…

Astrophysics of Galaxies · Physics 2015-06-04 Ronnie Jansson , Glennys R. Farrar

Galaxies are observed to host magnetic fields with a typical total strength of around 15microgauss. A coherent large-scale field constitutes up to a few microgauss of the total, while the rest is built from strong magnetic fluctuations over…

Astrophysics of Galaxies · Physics 2024-01-09 Maarit J. Korpi-Lagg , Mordecai-Mark Mac Low , Frederick A. Gent

We present an effectively global analytical asymptotic galactic dynamo solution for the regular magnetic field of an axisymmetric thin disc in the saturated state. This solution is constructed by combining two well-known types of local…

Astrophysics of Galaxies · Physics 2016-09-02 Luke Chamandy

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

Correlation analysis is obtained among Faraday rotation measure, HI column density, thermal and synchrotron radio brightness using archival all-sky maps of the Galaxy. A method is presented to calculate the magnetic strength and its…

Astrophysics of Galaxies · Physics 2019-08-29 Y. Sofue , H. Nakanishi , K. Ichiki

Magnetic fields permeate the diffuse interstellar medium (ISM) of the Milky Way, and are essential to explain the dynamical evolution and current shape of the Galaxy. Magnetic fields reveal themselves via their influence on the surrounding…

Astrophysics of Galaxies · Physics 2024-10-23 Sebastian Hutschenreuter , Marijke Haverkorn , Philipp Frank , Nergis C. Raycheva , Torsten A. Enßlin

Galactic dynamo models have generally relied on input parameters that are very challenging to constrain. We address this problem by developing a model that uses observable quantities as input: the galaxy rotation curve, the surface…

Astrophysics of Galaxies · Physics 2024-04-04 Luke Chamandy , Rion Glenn Nazareth , Gayathri Santhosh

We present estimates of magnetic field in a number of AGNs from the Spectropolarimetric atlas of Smith, Young & Robinson (2002) from the observed degrees of linear polarization and the positional angles of spectral lines (H-alpha) (broad…

High Energy Astrophysical Phenomena · Physics 2015-06-04 N. A. Silant'ev , Yu. N. Gnedin , S. D. Buliga , M. Yu. Piotrovich , T. M. Natsvlishvili

The evolution of three-dimensional, large-scale, magnetic fields, in a galactic disk is investigated numerically. The N-body simulations of galactic dynamics are incorporated into the kinematic calculations of induction equations to study…

Astrophysics · Physics 2007-05-23 K. Otmianowska-Mazur , S. von Linden , H. Lesch , G. Skupniewicz

From our radio continuum and polarization observations of a sample of spiral galaxies with different morphological types, inclinations, and star formation rates (SFR) we found that galaxies with low SFR have higher thermal fractions/…

Astrophysics · Physics 2008-06-13 Marita Krause

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

We present a study of the magnetic field of the Large Magellanic Cloud (LMC), carried out using diffuse polarized synchrotron emission data at 1.4 GHz acquired at the Parkes Radio Telescope and the Australia Telescope Compact Array. The…

The main observational results from radio continuum and polarization observations about the magnetic field strength and large-scale pattern for face-on and edge-on spiral galaxies are summarized and compared within our sample of galaxies of…

Astrophysics · Physics 2009-05-07 Marita Krause

Polarization data from high mass star formation regions (W51 e2/e8, Orion BN/KL) are used to derive statistical properties of the plane of sky projected magnetic field. Structure function and auto-correlation function are calculated for…

Solar and Stellar Astrophysics · Physics 2015-05-19 Patrick M. Koch , Ya-Wen Tang , Paul T. P. Ho

The magnetic fields observed in the Milky~Way and nearby galaxies appear to be in equipartition with the turbulent, thermal, and cosmic ray energy densities, and hence are expected to be dynamically important. However, the origin of these…

A fully three-dimensional computation of induction processes in a disk is performed to investigate the evolution of a large-scale magnetic field in gas-rich barred and spiral galaxies in the presence of field diffusion. As input parameters…

Astrophysics · Physics 2007-05-23 S. von Linden , K. Otmianowska-Mazur , H. Lesch , G. Skupniewicz

Magnetic fields in the ionized medium of the disk and halo of the Milky Way impose Faraday rotation on linearly polarized radio emission. We compare two surveys mapping the Galactic Faraday rotation, one showing the rotation measures of…

We present a method for parametric modelling of the physical components of the Galaxy's magnetised interstellar medium, simulating the observables, and mapping out the likelihood space using a Markov Chain Monte-Carlo analysis. We then…

Astrophysics of Galaxies · Physics 2010-01-29 T. R. Jaffe , J. P. Leahy , A. J. Banday , S. M. Leach , S. R. Lowe , A. Wilkinson