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Related papers: Dynamo in Protostar

200 papers

The present-day Universe is highly magnetized, even though the first magnetic seed fields were most probably extremely weak. To explain the growth of the magnetic field strength over many orders of magnitude fast amplification processes…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jennifer Schober , Dominik Schleicher , Stefano Bovino , Ralf S. Klessen

In this work, the gas infall and the formation of outflows around low and high mass protostars are investigated. A radial self-similar approach to model the transit of the molecular gas around the central object is employed. We include…

Astrophysics · Physics 2009-11-13 C. Combet , T. Lery , G. C. Murphy

The remanent magnetisation of meteorite material in the solar system indicates that magnetic fields of several Gauss are present in the protoplanetary disk. It is shown that such relativelystrong magnetic fields can be generated in dusty…

Astrophysics · Physics 2007-05-23 G. T. Birk , H. Wiechen , A. Kopp , H. Lesch

Enormous progress has been made on observing stellar magnetism in stars from the main sequence through to compact objects. Recent data have thrown into sharper relief the vexed question of the origin of stellar magnetic fields, which…

Solar and Stellar Astrophysics · Physics 2015-06-24 Lilia Ferrario , Andrew Melatos , Jonathan Zrake

In dilute astrophysical plasmas, the collisional mean free path of a particle can exceed its Larmor radius. Under these conditions, the thermal conductivity and viscosity of the plasma can be dramatically altered. This alteration allows…

Astrophysics · Physics 2009-11-11 Tanim Islam , Steven Balbus

It is shown that protostrange stars (PSSs) can be convective and that there are two possible scenarios describing their turbulence. Besides the local turbulence on the scale which is less than the mean free path of neutrinos, large-scale…

Astrophysics · Physics 2010-11-19 R. X. Xu , F. H. Busse

Dynamo action in fully convective stars is a debated issue that also questions our understanding of magnetic field generation in partly convective Sun-like stars. During the past few years, spectropolari- metric observations have…

Solar and Stellar Astrophysics · Physics 2013-11-21 J. Morin , X. Delfosse , J. -F. Donati , E. Dormy , T. Forveille , M. Jardine , P. Petit , M. Schrinner

Via amplification by turbulent dynamo, magnetic fields can be potentially important for the formation of the first stars. To examine the dynamo behavior during the gravitational collapse of primordial gas, we extend the theory of nonlinear…

Solar and Stellar Astrophysics · Physics 2020-08-26 Siyao Xu , Alex Lazarian

It is shown that in strongly magnetized neutron stars, there exist upper limits of magnetic field strength, beyond which the self energies for both neutron and proton components of neutron star matter become complex in nature. As a…

Astrophysics · Physics 2008-11-26 Somenath Chakrabarty

We present three-dimensional simulations of the dynamical bar-mode instability in magnetized and differentially rotating stars in full general relativity. Our focus is on the effects that magnetic fields have on the dynamics and the onset…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Luca Franci , Roberto De Pietri , Kyriaki Dionysopoulou , Luciano Rezzolla

The turnover of interstellar gas on $\sim 10^9$yr timescales argues for the continuous operation of a galactic dynamo. The conductivity of interstellar gas is so high that the dynamo must be "fast" - i.e. the magnetic field must be…

Astrophysics · Physics 2008-05-06 Ellen G. Zweibel Fabian Heitsch

Stellar magnetism plays an important role in stellar evolution theory. Approximatively 10% of observed main sequence (MS) and pre-main-sequence (PMS) radiative stars exhibit surface magnetic fields above the detection limit, raising the…

Solar and Stellar Astrophysics · Physics 2018-01-24 Jérémie Vidal , David Cébron , Nathanaël Schaeffer , Rainer Hollerbach

We investigate the evolution of magnetized protoneutron stars (PNSs) through four schematic stages: neutrino trapped, deleptonization, neutrino transparent, and the final cold, catalyzed neutron star (NS). Using a quasi static approximation…

High Energy Astrophysical Phenomena · Physics 2026-01-08 Harsh Chandrakar , Adamu Issifu , Prashant Thakur , T. K. Jha , Aravind Taridalu

M dwarfs are low-mass main-sequence stars, the most numerous type of stars in the solar neighbourhood, which are known to have significant magnetic activity. The aim of this work is to explore the dynamo solutions and magnetic fields of…

Solar and Stellar Astrophysics · Physics 2022-06-29 Carolina A. Ortiz-Rodríguez , Dominik R. G. Schleicher , Petri J. Käpylä , Felipe H. Navarrete

We explore the effects of magnetic energy dissipation on the formation of the first stars. For this purpose, we follow the evolution of primordial chemistry in the presence of magnetic fields in the post-recombination universe until the…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-28 Dominik R. G. Schleicher , Daniele Galli , Simon C. O. Glover , Robi Banerjee , Francesco Palla , Raffaella Schneider , Ralf S. Klessen

In many astrophysical environments, self-gravity can generate kinetic energy, which, in principle, is available for driving dynamo action. Using direct numerical simulations, we show that in unstirred self-gravitating subsonic turbulence…

Astrophysics of Galaxies · Physics 2022-04-20 Axel Brandenburg , Evangelia Ntormousi

Convection in massive main sequence stars generates large scale magnetic fields in their cores which persists as they evolve up the red giant branch. The remnants of these fields may take the form of the Prendergast magnetic field, a…

Solar and Stellar Astrophysics · Physics 2022-10-12 Emma Kaufman , Daniel Lecoanet , Evan H. Anders , Benjamin P. Brown , Geoffrey M. Vasil , Jeffrey S. Oishi , Keaton J. Burns

We investigate the impact of strong initial magnetic fields in core-collapse supernovae of non-rotating progenitors by simulating the collapse and explosion of a 16.9 Msun star for a strong- and weak-field case assuming a twisted-torus…

High Energy Astrophysical Phenomena · Physics 2022-11-30 Vishnu Varma , Bernhard Mueller , Fabian R. N. Schneider

Extremely strong magnetic fields of the order of $10^{15}\,{\rm G}$ are required to explain the properties of magnetars, the most magnetic neutron stars. Such a strong magnetic field is expected to play an important role for the dynamics of…

High Energy Astrophysical Phenomena · Physics 2017-10-25 Jerome Guilet , Ewald Mueller , Hans-Thomas Janka , Tomasz Rembiasz , Martin Obergaulinger , Pablo Cerda-Duran , Miguel-Angel Aloy

The explanation of the observed galactic magnetic fields may require the existence of a primordial magnetic field. Such a field may arise during the early cosmological phase transitions, or because of other particle physics related…

Astrophysics · Physics 2009-10-30 Kari Enqvist