English
Related papers

Related papers: Simulated Rotation Measure Sky from Primordial Mag…

200 papers

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

Turbulence is ubiquitous in many astrophysical systems like galaxies, galaxy clusters and possibly even the IGM filaments. We study fluctuation dynamo action in turbulent systems focusing on one observational signature; the Faraday rotation…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-09 Pallavi Bhat , Kandaswamy Subramanian

We present a suite of models of the coherent magnetic field of the Galaxy (GMF) based on new divergence-free parametric functions describing the global structure of the field. The model parameters are fit to the latest full-sky Faraday…

Astrophysics of Galaxies · Physics 2024-08-14 Michael Unger , Glennys R. Farrar

We present a model for the seeding and evolution of magnetic fields in galaxies by supernovae (SN). SN explosions during galaxy assembly provide seed fields, which are subsequently amplified by compression, shear flows and random motions.…

Astrophysics of Galaxies · Physics 2017-01-11 Alexander M. Beck , Klaus Dolag

Despite their ubiquity, there are many open questions regarding galactic and cosmic magnetic fields. Specifically, current observational constraints cannot rule out if magnetic fields observed in galaxies were generated in the Early…

Astrophysics of Galaxies · Physics 2021-07-30 Sergio Martin-Alvarez , Harley Katz , Debora Sijacki , Julien Devriendt , Adrianne Slyz

Faraday rotation measures (RMs) of extragalactic radio sources provide information on line-of-sight magnetic fields, including contributions from our Galaxy, source environments, and the intergalactic medium (IGM). Looking at differences in…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-26 T. Vernstrom , B. Gaensler , L. Rudnick , H. Andernach

The origin of magnetic fields in clusters of galaxies is still an unsolved problem, which is largely due to our poor understanding of initial seed magnetic fields. If the seed magnetic fields have primordial origins, it is likely that…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Jungyeon Cho

A primordial magnetic field (PMF) present before recombination can leave specific signatures on the cosmic microwave background (CMB) fluctuations. Of particular importance is its contribution to the B-mode polarization power spectrum.…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Alex Zucca , Yun Li , Levon Pogosian

The forthcoming new-generation radio telescope SKA (Square Kilometre Array) and its precursors will provide a rapidly growing number of polarized radio sources. Our analysis aims on what can be learned from these sources concerning the…

Astrophysics · Physics 2009-11-13 Rodion Stepanov , Tigran G. Arshakian , Rainer Beck , Peter Frick , Marita Krause

The origin of magnetic fields in the Universe is an open problem in astrophysics and fundamental physics. "Cosmic Magnetism" has been accepted as Key Science Project both for the Low Frequency Array (LOFAR, under construction) and the…

Astrophysics · Physics 2008-04-30 Rainer Beck

The hypothesis of a universal initial mass function (IMF) -- motivated by observations in nearby stellar systems -- has been recently challenged by the discovery of a systematic variation of the IMF with the central velocity dispersion,…

We recently predicted the existence of random primordial magnetic fields (RPMF) in the form of randomly oriented cells with dipole-like structure with a cell size $L_0$ and an average magnetic field $B_0$. Here we investigate models for…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-24 Rafael S. de Souza , Luiz Felippe S. Rodrigues , Reuven Opher

The origin of extragalactic magnetic fields is still poorly understood. Based on a dedicated suite of cosmological magneto-hydrodynamical simulations with the ENZO code we have performed a survey of different models that may have caused…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 F. Vazza , M. Brüggen , C. Gheller , S. Hackstein , D. Wittor , P. M. Hinz

The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms…

Astrophysics · Physics 2007-05-23 Kari Enqvist

Strong, globally-organized magnetic fields are found for a small fraction of O, B, and A stars. At the same time, many theoretical and indirect observational studies suggested ubiquitous presence of weak localized magnetic fields at the…

Solar and Stellar Astrophysics · Physics 2015-06-15 O. Kochukhov , N. Sudnik

If a small fraction of Fast Radio Bursts (FRBs) are associated with Gamma-Ray Bursts (GRBs), as recently suggested by Zhang, the combination of redshift measurements of GRBs and dispersion measure (DM) measurements of FRBs opens a new…

High Energy Astrophysical Phenomena · Physics 2014-03-05 Wei Deng , Bing Zhang

Since the energy momentum tensor of a magnetic field always contains a spin-2 component in its anisotropic stress, stochastic primordial magnetic field (PMF) in the early universe must generate stochastic gravitational wave (GW) background.…

Astrophysics · Physics 2010-01-27 Shuang Wang

Magnetic fields in nearby, star-forming galaxies reveal both large-scale patterns and small-scale structures. A large-scale field reversal may exist in the Milky Way but no such reversals have been observed so far in external galaxies. The…

Astrophysics of Galaxies · Physics 2015-05-30 David Moss , Rodion Stepanov , Tigran Arshakian , Rainer Beck , Marita Krause , Dmitri Sokoloff

The simulations of the formation of cosmological structure allows to determine the spatial inhomogeneity of cosmic magnetic fields. Such simulations, however, do not give an absolute number for the strength of the magnetic field due to…

Astrophysics · Physics 2007-05-23 Peter L. Biermann , Hyesung Kang , Joerg P. Rachen , Dongsu Ryu

Faraday rotation (RM) probes of magnetic fields in the universe are sensitive to cosmological and evolutionary effects as $z$ increases beyond $\sim $1 because of the scalings of electron density and magnetic fields, and the growth in the…

Astrophysics · Physics 2009-11-13 P. P. Kronberg , M. L. Bernet , F. Miniati , S. J. Lilly , M. B. Short , D. M. Higdon