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Related papers: Primordial magnetogenesis

200 papers

Primordial magnetic fields and massive neutrinos can leave an interesting signal in the CMB temperature and polarization. We perform a systematic analysis of general perturbations in the radiation-dominated universe, accounting for any…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 J. Richard Shaw , Antony Lewis

The presence of a strong magnetic field is a feature common to a significant fraction of degenerate stars, yet little is understood about field origin and evolution. New observational constraints from volume-limited surveys point to a more…

Solar and Stellar Astrophysics · Physics 2022-08-24 Stefano Bagnulo , John D. Landstreet

The recent years have brought great advances in our knowledge of magnetic fields in cool giant and supergiant stars. For example, starspots have been directly imaged on the surface of an active giant star using optical interferometry, and…

Solar and Stellar Astrophysics · Physics 2017-12-15 Heidi Korhonen

Observations of stable mainly dipolar magnetic fields at the surface of ~7% of single hot stars indicate that these fields are of fossil origin, i.e. they descend from the seed field in the molecular clouds from which the stars were formed.…

Solar and Stellar Astrophysics · Physics 2015-02-03 C. Neiner , S. Mathis , E. Alecian , C. Emeriau , J. Grunhut , the BinaMIcS , MiMeS collaborations

The prevailing theory for the origin of cosmic magnetic fields is that they have been amplified to their present values by the turbulent dynamo inductive action in the protogalactic and galactic medium. Up to now, in calculation of the…

Astrophysics · Physics 2010-11-05 Leonid Malyshkin , Russell Kulsrud

The effects of magnetic fields on Big Bang Nucleosynthesis(BBN) have been calculated, and the impact on the abundances of the light elements have been investigated numerically. An upper limit on the strength of primordial magnetic fields…

Astrophysics · Physics 2009-12-30 Baolian Cheng , David N. Schramm , James W. Truran

We propose that the overlapping shock fronts from young supernova remnants produce a locally unsteady, but globally steady large scale spiral shock front in spiral galaxies, where star formation and therefore massive star explosions…

Astrophysics · Physics 2007-05-23 Peter L. Biermann , Cristina F. Galea

It is now well-known that the surface magnetic fields observed in cool, lower-mass stars on the main sequence (MS) are generated by dynamos operating in their convective envelopes. However, higher-mass stars (above 1.5 Msun) pass their MS…

Astrophysics · Physics 2009-11-13 E. Alecian , G. A. Wade , C. Catala

We show that coherent magnetic field is generated spontaneously when a large domain wall is created in the early universe. It is caused by two dimensional massless fermions bounded to the domain wall soliton. We point out that the magnetic…

High Energy Physics - Phenomenology · Physics 2009-10-28 Aiichi Iwazaki

We investigate primordial magnetogenesis within a quantum bouncing model driven by a scalar field, focusing on various non-minimal couplings between the electromagnetic field and the scalar field. We test three cases: no coupling, a Cauchy…

General Relativity and Quantum Cosmology · Physics 2024-11-06 Marcus V. Bomfim , Emmanuel Frion , Nelson Pinto-Neto , Sandro D. P. Vitenti

Magnetic fields have been detected on stars across the H-R diagram and substellar objects either directly by their effect on the formation of spectral lines, or through the activity phenomena they power which can be observed across a large…

Solar and Stellar Astrophysics · Physics 2015-06-11 J. Morin

We review our current understanding of galactic dynamo theory, paying particular attention to numerical simulations both of the mean-field equations and the original three-dimensional equations relevant to describing the magnetic field…

Astrophysics of Galaxies · Physics 2014-12-12 Axel Brandenburg

Large-scale magnetic fields are observed today to be coherent on galactic scales. While there exists an explanation for their amplification and their specific configuration in spiral galaxies -- the dynamo mechanism -- a satisfying…

High Energy Physics - Theory · Physics 2009-12-04 Rhiannon Gwyn , Stephon Alexander , Robert H. Brandenberger , Keshav Dasgupta

Magnetic fields are known to reside in many astrophysical objects and are now believed to be crucially important for the creation of phenomena on a wide variety of scales. However, the role of the magnetic field in the bodies that we…

Astrophysics · Physics 2009-11-13 L. J. Silvers

We show that the decaying magnetohydrodynamic turbulence leads to a more rapid growth of the correlation length of a primordial magnetic field than that caused by the expansion of the Universe. As an example, we consider the magnetic fields…

High Energy Physics - Phenomenology · Physics 2016-08-25 D. T. Son

A small fraction of the population of intermediate-mass and massive stars host strong and stable magnetic fields organised on large scales. These fields are believed to be remnants of star formation. It is however not clear how such fossil…

Solar and Stellar Astrophysics · Physics 2021-03-10 E. Alecian , F. Villebrun , J. Grunhut , G. Hussain , C. Neiner , G. A. Wade

There is evidence that cosmic rays were present in galaxies at moderately high redshift. This suggests that magnetic fields were also present. If cosmic rays and magnetic fields must always be close to equipartition, as they are to an order…

Astrophysics · Physics 2009-11-07 Ellen G. Zweibel

Origin of the magnetic field ubiquitous in the Universe is studied based on the Biermann mechanism, which is expected to work in the non-barotropic region. We perform a series of two-dimensional MHD simulations of the first generation…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-17 Hidekazu Hanayama , Keitaro Takahashi , Kohji Tomisaka

We study limits on a primordial magnetic field arising from cosmological data, including that from big bang nucleosynthesis, cosmic microwave background polarization plane Faraday rotation limits, and large-scale structure formation. We…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-27 Tina Kahniashvili , Alexander G. Tevzadze , Shiv K. Sethi , Kanhaiya Pandey , Bharat Ratra

Observational evidence for strong magnetic fields throughout the envelopes of evolved stars is increasing. Many of the instruments coming on line in the near-future will be able to make further contributions to this field. Specifically,…

Solar and Stellar Astrophysics · Physics 2010-10-07 Wouter Vlemmings
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