English
Related papers

Related papers: Dynamo in Protostar

200 papers

Protostellar flares are rapid magnetic energy release events associated with formation of hot plasma in protostars. In the previous models of protostellar flares, the interaction between a protostellar magnetosphere with the surrounding…

Solar and Stellar Astrophysics · Physics 2019-06-12 Shinsuke Takasao , Kengo Tomida , Kazunari Iwasaki , Takeru K. Suzuki

Numerous studies have investigated the role of thermal instability in regulating the phase transition between the cold cloudy and warm diffuse medium of the interstellar medium. Considerable interest has also been devoted in investigating…

Astrophysics of Galaxies · Physics 2015-05-20 Maarit J. Mantere , Elizabeth Cole

We perform the first magnetohydrodynamical simulations of tidal disruptions of stars by supermassive black holes. We consider stars with both tangled and ordered magnetic fields, for both grazing and deeply disruptive encounters. When the…

High Energy Astrophysical Phenomena · Physics 2017-01-18 James Guillochon , Michael McCourt

Recent numerical MHD simulations suggest that magnetic activity may occur in late-type giants. A entire red supergiant with stellar parameters equal to Betelgeuse was modelled in 3d with the high-order "Pencil Code". Linear kinematic and…

Astrophysics · Physics 2007-05-23 S. B. F. Dorch

We discuss the possibility to launch outflows from the close vicinity of a protoplanetary core considering a scenario where the protoplanet surrounded by a circum-planetary accretion disk is located in a circum-stellar disk. For the…

Astrophysics · Physics 2009-11-10 Christian Fendt

Most large-scale planetary magnetic fields are thought to be driven by low Rossby number convection of a low magnetic Prandtl number fluid. Here kinematic dynamo action is investigated with an asymptotic, rapidly rotating dynamo model for…

Geophysics · Physics 2016-12-14 Michael A. Calkins , Louie Long , David Nieves , Keith Julien , Steven M. Tobias

In their early stages, protoplanetary discs are sufficiently massive to undergo gravitational instability (GI). This instability is thought to be involved in mass accretion, planet formation via gas fragmentation, the generation of spiral…

Earth and Planetary Astrophysics · Physics 2021-06-30 A. Riols , W. Xu , G. Lesur , M. W. Kunz , H. Latter

We present our current understanding of the formation and early evolution of protostars, protoplanetary disks, and the driving of outflows as dictated by the interplay of magnetic fields and partially ionized gas in molecular cloud cores.…

Solar and Stellar Astrophysics · Physics 2022-09-29 Yusuke Tsukamoto , Anaëlle Maury , Benoît Commerçon , Felipe O. Alves , Erin G. Cox , Nami Sakai , Tom Ray , Bo Zhao , Masahiro N. Machida

Solar magnetic fields comprise an 11-year activity cycle, represented by the number of sunspots. The maintenance of such a solar magnetic field can be attributed to fluid motion in the convection zone, i.e. a dynamo. This study conducts the…

Solar and Stellar Astrophysics · Physics 2022-08-24 Ryota Shimada , Hideyuki Hotta , Takaaki Yokoyama

The origin of strong magnetic fields in the Universe can be explained by amplifying weak seed fields via turbulent motions on small spatial scales and subsequently transporting the magnetic energy to larger scales. This process is known as…

After electron-positron annihilation and prior to photon decoupling the magnetic Reynolds number is approximately twenty orders of magnitude larger than its kinetic counterpart which is, in turn, smaller than one. In this globally neutral…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Massimo Giovannini

In this review, I will summarise what we know about magnetic fields in stars and what the origin of these magnetic fields may be. I will address the issue of whether the magnetic flux is conserved from pre-main sequence to the compact star…

Solar and Stellar Astrophysics · Physics 2018-01-30 Lilia Ferrario

We conduct one-dimensional stellar evolutionary numerical simulations under the assumption that an efficient dynamo operates in the core of massive stars years to months before core collapse and find that the magnetic activity enhances mass…

High Energy Astrophysical Phenomena · Physics 2024-07-19 Tamar Cohen , Noam Soker

A neutron star is one of the possible end states of a massive star. It is compressed by gravity and stabilized by the nuclear degeneracy pressure. Despite its name, the composition of these objects is not exactly known. However, from the…

Nuclear Theory · Physics 2022-06-10 J. P. W. Diener

Are the kG-strength magnetic fields observed in young stars a fossil field left over from their formation or are they generated by a dynamo? We use radiation non-ideal magnetohydrodynamics simulations of the gravitational collapse of a…

Solar and Stellar Astrophysics · Physics 2018-09-12 James Wurster , Matthew R. Bate , Daniel J. Price

The magnetization of solar and extrasolar gas giants is critically dependent on electronic and mass transport coefficients of their convective fluid interiors. We analyze recent laboratory experimental results on metallic hydrogen to derive…

Earth and Planetary Astrophysics · Physics 2018-07-20 Mohamed Zaghoo , G. W. Collins

We report a series of numerical simulations showing that the critical magnetic Reynolds number Rm_c for the nonhelical small-scale dynamo depends on the Reynolds number Re. Namely, the dynamo is shut down if the magnetic Prandtl number…

Astrophysics · Physics 2009-11-16 A. A. Schekochihin , S. C. Cowley , J. L. Maron , J. C. McWilliams

The protostellar jets driven by the formation of the first stars are studied by using MHD nested grid simulations. Starting from a slowly rotating spherical cloud of 5.1 times 10^4 Msun permeated by a uniform magnetic field, we follow the…

We explore the influence of non-axisymmetric modes on the dynamics of the collapsed core of rotating, magnetized high-mass stars in three-dimensional simulations of a rapidly rotating star with an initial mass of $M_{ZAMS}$ = 35 solar…

High Energy Astrophysical Phenomena · Physics 2021-05-05 Martin Obergaulinger , Miguel-Ángel Aloy

The impact of the magnetic field on postbounce supernova dynamics of non-rotating stellar cores is studied by performing three-dimensional magnetohydrodynamics simulations with spectral neutrino transport. The explodability of strongly and…

High Energy Astrophysical Phenomena · Physics 2022-08-19 Jin Matsumoto , Yuta Asahina , Tomoya Takiwaki , Kei Kotake , Hiroyuki R. Takahashi
‹ Prev 1 3 4 5 6 7 10 Next ›