English
Related papers

Related papers: Intergalactic magnetic field spectra from diffuse …

200 papers

The strengths of magnetic fields in interstellar gas clouds are obtained through observations of the circular polarization of spectral line radiation. Irregularities in this magnetic field may be present due to turbulence, waves or perhaps…

Astrophysics · Physics 2009-10-31 W. D. Watson , D. S. Wiebe , R. M. Crutcher

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 demonstrate that the inclusion of the helicity flux in the magnetic helicity balance in the nonlinear stage of galactic dynamo action results in a radical change in the magnetic field dynamics. The equilibrium value of the large-scale…

Astrophysics · Physics 2007-05-23 N. Kleeorin , D. Moss , I. Rogachevskii , D. Sokoloff

In this paper, we study analytically the process of external generation and subsequent free evolution of the lepton chiral asymmetry and helical magnetic fields in the early hot universe. This process is known to be affected by the Abelian…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-18 Maksym Sydorenko , Oleksandr Tomalak , Yuri Shtanov

We investigate the generation of helical magnetic fields and address the baryon asymmetry of the universe from an inflationary magnetogenesis scenario, in which the conformal and parity symmetries of the electromagnetic field are broken…

General Relativity and Quantum Cosmology · Physics 2022-04-12 Kazuharu Bamba , Sergei D. Odintsov , Tanmoy Paul , Debaprasad Maity

{Magnetic fields exist on all scales in our Galaxy. There is a controversy about whether the magnetic fields in molecular clouds are preserved from the permeated magnetic fields in the interstellar medium (ISM) during cloud formation. We…

Astrophysics · Physics 2008-08-14 J. L. Han , J. S. Zhang

Because cosmic rays are charged particles scrambled by magnetic fields, combining direct measurements with other observations is crucial to understanding their origin and propagation. As energetic particles traverse matter and…

High Energy Astrophysical Phenomena · Physics 2019-08-13 L. Tibaldo

One way in which the Canadian Galactic Plane Survey has made an important contribution to the understanding of the Galactic interstellar medium is through its polarization surveys. Investigation of these data has enabled a big step in the…

Astrophysics of Galaxies · Physics 2010-12-20 Marijke Haverkorn

(abridged) A detailed examination of the evolution of stochastic magnetic fields between high cosmic temperatures and the present epoch is presented. A simple analytical model matching the results of the 3D MHD simulations allows for the…

Astrophysics · Physics 2009-11-10 Robi Banerjee , Karsten Jedamzik

A complete numerical calculation of the temperature anisotropies and polarization of the cosmic microwave background (CMB) in the presence of a stochastic helical magnetic field is presented which includes the contributions due to scalar,…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Kerstin E. Kunze

Unveiling the intergalactic magnetic field (IGMF) in filaments of galaxies is a very important and challenging subject in modern astronomy. In order to probe the IGMF from rotation measures (RMs) of extragalactic radio sources, we need to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Takuya Akahori , Kohei Kumazaki , Keitaro Takahashi , Dongsu Ryu

We explore the generation of large-scale magnetic fields in the so-called moduli inflation. The hypercharge electromagnetic fields couple to not only a scalar field but also a pseudoscalar one, so that the conformal invariance of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-30 Kazuharu Bamba

Aims. This article shows the first evidence for gravitational lensing phenomena in high energy gamma-rays. This evidence comes from the observation of a gravitational lens induced echo in the light curve of the distant blazar PKS 1830-211.…

High Energy Astrophysical Phenomena · Physics 2015-05-20 A. Barnacka , J-F. Glicenstein , Y. Moudden

Pulsed gamma rays have been detected with the Fermi Large Area Telescope (LAT) from more than 20 millisecond pulsars (MSPs), some of which were discovered in radio observations of bright, unassociated LAT sources. We have fit the radio and…

High Energy Astrophysical Phenomena · Physics 2011-11-04 Tyrel J. Johnson , Alice K. Harding , Christo Venter

Observational evidence for the existence of cosmic magnetic fields in intergalactic space coherent over Mpc scales is presented. Using an unprecedentedly large sample of Faraday rotation measures of radio sources from the NRAO VLA Sky…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-16 Jounghun Lee , Ue-Li Pen , A. Russell Taylor , Jeroen M. Stil , Caleb Sunstrum

We study diffuse gamma-ray emission at intermediate Galactic latitudes measured by the Fermi Large Area Telescope with the aim of searching for a signal from dark matter annihilation or decay. In the absence of a robust dark matter signal,…

High Energy Astrophysical Phenomena · Physics 2013-04-10 G. Zaharijas , J. Conrad , A. Cuoco , Z. Yang

We improve on the model of the Galactic Magnetic Field (GMF) from Jansson \& Farrar (2012), which was constrained using all-sky rotation measures of extragalactic sources and polarized and unpolarized synchrotron emission data from WMAP. We…

Astrophysics of Galaxies · Physics 2017-07-14 Michael Unger , Glennys R. Farrar

The Fermi Large Area Telescope (Fermi LAT) provides long term systematic monitoring observations of the gamma-ray emission from blazars. The variability properties and the correlation with other wavelength bands are important clues for the…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Stefan Larsson

We propose that magnetic reconnection at the heliopause only occurs where the interstellar magnetic field points nearly anti-parallel to the heliospheric field. By using large-scale magnetohydrodynamic (MHD) simulations of the heliosphere…

Earth and Planetary Astrophysics · Physics 2015-05-14 M. Swisdak , M. Opher , J. F. Drake , F. Alouani Bibi

Aims. We use 5 years of Fermi-LAT data towards the Galactic-centre giant molecular cloud complex, Sagittarius B, to test questions of how well-mixed the Galactic component of cosmic rays are and what the level of the cosmic-ray sea in…

High Energy Astrophysical Phenomena · Physics 2015-08-12 Rui-zhi Yang , David I. Jones , Felix Aharonian