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Related papers: Protogalactic evolution and magnetic fields

200 papers

Magnetic fields in galaxies are believed to be the result of dynamo amplification of initially weak seed fields, reaching equipartition strength inside the interstellar medium. The small-scale dynamo appears to be a viable mechanism to…

Astrophysics of Galaxies · Physics 2017-08-16 Michael Rieder , Romain Teyssier

We show, using a covariant and gauge-invariant charged multifluid perturbation scheme, that velocity perturbations of the matter-dominated dust Friedmann-Lemaitre-Robertson-Walker (FLRW) model can lead to the generation of cosmic magnetic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Gerold Betschart , Peter K. S. Dunsby , Mattias Marklund

Magnetic fields are amplified as a consequence of galaxy formation and turbulence-driven dynamos. Galaxy mergers can potentially amplify the magnetic fields from their progenitors, making the magnetic fields dynamically important. However,…

Astrophysics of Galaxies · Physics 2021-04-05 Enrique Lopez-Rodriguez

Detailed physical processes of magnetic field generation from density fluctuations in the pre-recombination era are studied. Solving Maxwell equations and the generalized Ohm's law, the evolutions of the net charge density, the electric…

Astrophysics · Physics 2008-11-26 Keitaro Takahashi , Kiyotomo Ichiki , Naoshi Sugiyama

Recent asteroseismic analyses have revealed the presence of strong (B $\gtrsim 10^5$ G) magnetic fields in the cores of many red giant stars. Here, we examine the implications of these results for the evolution of stellar magnetic fields,…

Solar and Stellar Astrophysics · Physics 2016-06-15 Matteo Cantiello , Jim Fuller , Lars Bildsten

The origin of our universe's cosmological magnetic fields remains a mystery. In this study, we consider whether these magnetic fields could have been generated in the early universe by a population of charged, spinning primordial black…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-31 Dan Hooper , Aurora Ireland , Gordan Krnjaic

We study the primordial magnetic field generated by stochastic currents produced by scalar charged particles created at the beginning of the radiation dominated epoch. We find that for the mass range 10^(-6)GeV \leq m \leq 10^2 GeV, a field…

Astrophysics · Physics 2008-11-26 Esteban A. Calzetta , Alejandra Kandus , Francisco D. Mazzitelli

The generation of primordial magnetic fields from cosmological phase transitions is discussed, paying particular attention to the electroweak transition and to the various definitions of the `average' field that have been put forward. It is…

Astrophysics · Physics 2016-08-25 Mark Hindmarsh , Allen Everett

We give an improved estimate of primordial magnetic fields generated during cosmological first order phase transitions. We examine the charge distribution at the nucleated bubble wall and its dynamics. We consider instabilities on the…

Astrophysics · Physics 2009-10-28 Guenter Sigl , Angela Olinto , Karsten Jedamzik

Numerical simulations have shown that the strength of planetary magnetic fields depends on the convective energy flux emerging from planetary interiors. Here we model the interior structure of gas giant planets using \texttt{MESA}, to…

Earth and Planetary Astrophysics · Physics 2024-11-13 Konstantinos Kilmetis , Aline A. Vidotto , Andrew Allan , Daria Kubyshkina

The origin and evolution of magnetic fields in the Universe is still an open question. Their observations in galaxies suggest strong magnetic fields already at high redshift as well as at present time. However, neither primordial magnetic…

Astrophysics of Galaxies · Physics 2017-04-21 Michael Rieder , Romain Teyssier

The amplification of primordial magnetic fields via a small-scale turbulent dynamo during structure formation might be able to explain the observed magnetic fields in galaxy clusters. The magnetisation of more tenuous large-scale structures…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 F. Vazza , M. Brüggen , C. Gheller , P. Wang

We study the generation of strong large scale magnetic fields in dense quark matter. The magnetic field growth is owing to the magnetic field instability driven by the electroweak interaction of quarks. We discuss the situation when the…

High Energy Physics - Phenomenology · Physics 2016-11-16 Maxim Dvornikov

Isolated magnetic white dwarfs have field strengths ranging from kilogauss to gigagauss, and constitute an interesting class of objects. The origin of the magnetic field is still the subject of a hot debate. Whether these fields are fossil,…

Solar and Stellar Astrophysics · Physics 2016-02-17 Enrique García-Berro , Mukremin Kilic , S. O. Kepler

Magnetic fields correlated on several kiloparsec scales are seen in spiral galaxies. Their origin could be due to amplification of a small seed field by a turbulent galactic dynamo. We critically review the current status of the galactic…

Astrophysics · Physics 2007-05-23 Kandaswamy Subramanian

Magnetic fields are present in a wide variety of stars throughout the HR diagram and play a role at basically all evolutionary stages, from very-low-mass dwarfs to very massive stars, and from young star-forming molecular clouds and…

Solar and Stellar Astrophysics · Physics 2010-01-15 JF Donati , JD Landstreet

The detection of strong, large-scale magnetic fields at the surface of only the oldest population of white dwarfs might point towards a hidden internal magnetic field slowly rising to the surface. In addition, strong magnetic fields have…

Solar and Stellar Astrophysics · Physics 2026-04-15 Lukas Einramhof , Lisa Bugnet , Leila Magdalena Calcaferro , Lucas Barrault , Srijan Bharati Das

In star formation, magnetic fields act as a cosmic angular momentum extractor that increases mass accretion rates onto protostars and in the process, creates spectacular outflows. However, recently it has been argued that this magnetic…

Solar and Stellar Astrophysics · Physics 2014-11-20 Dennis F. Duffin , Ralph E. Pudritz

Magnetic fields likely play a key role in the dynamics and evolution of protoplanetary discs. They have the potential to efficiently transport angular momentum by MHD turbulence or via the magnetocentrifugal acceleration of outflows from…

Astrophysics · Physics 2009-06-23 Mark Wardle

Sufficiently large seeds for generating the observed (inter)galactic magnetic fields emerge naturally in string cosmology from the amplification of electromagnetic vacuum fluctuations due to a dynamical dilaton background. The success of…

High Energy Physics - Theory · Physics 2009-10-28 M. GasperinI , M. Giovannini , G. Veneziano