English
Related papers

Related papers: Fast dynamos in weakly ionized gases

200 papers

We have studied a sample of completely isolated galaxies by means of long-slit spectroscopy at the 6-m telescope. We have found that 7 of 12 (58 +/- 14 %) galaxies have revealed a presence of large-scale ionized-gas component which angular…

Astrophysics of Galaxies · Physics 2014-06-19 Ivan Katkov , Olga Sil'chenko , Victor Afanasiev

Magnetic fields grow quickly, even at early cosmological times, suggesting the action of a small-scale dynamo (SSD) in the interstellar medium (ISM) of galaxies. Many studies have focused on idealized, isotropic, homogeneous, turbulent…

Astrophysics of Galaxies · Physics 2023-02-15 Frederick A. Gent , Mordecai-Mark Mac Low , Maarit J. Korpi-Lagg , Nishant K. Singh

Observations have suggested that some low-mass stars have larger radii than predicted by 1-D structure models. Some theoretical models have invoked very strong interior magnetic fields (of order 1 MG or more) as a possible cause of such…

Solar and Stellar Astrophysics · Physics 2016-03-09 Matthew K. Browning , Maria A. Weber , Gilles Chabrier , Angela P. Massey

Magnetic fields of debated origin appear to permeate the Universe on all large scales. There is mounting evidence that supernovae produce not only roughly spherical ejecta and winds, but also highly relativistic jets of ordinary matter.…

Astrophysics · Physics 2009-11-11 Arnon Dar , A. De Rujula

Previously Liao and Shuryak [\textbf{Phys. Rev C (2008)}] have investigated electrical flux tubes in monopole plasmas, where magnetic fields are non-solenoidal in quark-QCD plasmas. In this paper slow dynamos in diffusive plasma…

Cosmology and Nongalactic Astrophysics · Physics 2009-01-23 Garcia de Andrade

In recent years evidence has accumulated that nearby spiral galaxies are surrounded by massive haloes of neutral and ionised gas. These gaseous haloes rotate more slowly than the disks and show inflow motions. They are clearly analogous to…

Astrophysics · Physics 2011-02-11 Filippo Fraternali , James Binney , Tom Oosterloo , Renzo Sancisi

After their initial formation, disk galaxies are observed to be rotationally stable over periods of >6 Gyr, implying that any large velocity disturbances of stars and gas clouds are damped rapidly on the timescale of their rotation.…

Astrophysics of Galaxies · Physics 2022-11-08 John Herbert Marr

The exteriors of stellar and galactic dynamos are usually modeled as current-free potential fields. A more realistic description might instead be that of a force-free magnetic field. Here, we suggest that, in the absence of outflows,…

High Energy Astrophysical Phenomena · Physics 2026-05-06 Axel Brandenburg , Oindrila Ghosh , Franco Vazza , Andrii Neronov

The release of spin-down energy by a magnetar is a promising scenario to power several classes of extreme explosive transients. However, it lacks a firm basis because magnetar formation still represents a theoretical challenge. Using the…

High Energy Astrophysical Phenomena · Physics 2020-03-17 Raphaël Raynaud , Jérôme Guilet , Hans-Thomas Janka , Thomas Gastine

Magnetic fields correlated on 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 review the current status of the galactic dynamo, especially…

Astrophysics · Physics 2007-05-23 Kandaswamy Subramanian

The Universe at present is highly magnetized, with fields of the order of a few 10^-5 G and coherence lengths larger than 10 kpc in typical galaxies like the Milky Way. We propose that the magnetic field was amplified to this values already…

Astrophysics of Galaxies · Physics 2015-06-17 Jennifer Schober , Dominik R. G. Schleicher , Ralf S. Klessen

M dwarfs are the most numerous stars in our Galaxy with masses between approximately 0.5 and 0.1 solar mass. Many of them show surface activity qualitatively similar to our Sun and generate flares, high X-ray fluxes, and large-scale…

Solar and Stellar Astrophysics · Physics 2018-01-29 D. Shulyak A. Reiners , A. Engeln , L. Malo , R. Yadav , J. Morin , O. Kochukhov

Several lines of evidence suggest that protogalactic and galactic environments manage to grow magnetic field very rapidly. This makes the theoretical problem of achieving rapid growth of magnetic fields in such environments difficult.…

Astrophysics · Physics 2009-11-10 D. S. Balsara , J. S. Kim , M. M. Mac Low , G. Mathews

The observed scale heights of extraplanar diffuse ionized gas (eDIG) layers exceed their thermal scale heights by a factor of a few in the Milky Way and other nearby edge-on disk galaxies. Here, we test a dynamical equilibrium model of the…

Astrophysics of Galaxies · Physics 2016-12-07 Erin Boettcher , Ellen G. Zweibel , J. S. Gallagher , Robert A. Benjamin

We present maps of total magnetic field using 'equipartition' assumptions for five nearby normal galaxies at sub-kpc spatial resolution. The mean magnetic field is found to be ~11 \mu G. The field is strongest near the central regions where…

Astrophysics of Galaxies · Physics 2015-06-15 Aritra Basu , Subhashis Roy

The maximum magnetic field strength generated by Weibel-type plasma instabilities is estimated for typical conditions in the interstellar medium. The relevant kinetic dispersion relations are evaluated by conducting a parameter study both…

High Energy Astrophysical Phenomena · Physics 2015-06-16 R. C. Tautz , J. Triptow

A new kind of dynamo utilizing flowing laboratory plasmas has been identified. Conversion of plasma kinetic energy to magnetic energy is verified numerically by kinematic dynamo simulations for magnetic Reynolds numbers above 210. As…

Astrophysics · Physics 2009-11-07 Zhehui Wang , Vladimir I. Pariev , Cris W. Barnes , Daniel C. Barnes

We study dissipation process of magnetic fields in the metallicity range $0-1 Z_{\odot}$ for contracting prestellar cloud cores. By solving non-equilibrium chemistry for important charged species including charged grains, we evaluate the…

Solar and Stellar Astrophysics · Physics 2015-06-23 Hajime Susa , Kentaro Doi , Kazuyuki Omukai

Upper bounds are derived on the amount of magnetic energy that can be generated by dynamo action in collisional and collisionless plasmas with and without external forcing. A hierarchy of mathematical descriptions is considered for the…

Plasma Physics · Physics 2017-01-11 P. Helander , M. Strumik , A. A. Schekochihin

Convection is one of the most important mixing processes in stellar interiors. Hydrodynamic mass entrainment can bring fresh fuel from neighboring stable layers into a convection zone, modifying the structure and evolution of the star.…

Solar and Stellar Astrophysics · Physics 2023-11-29 G. Leidi , R. Andrassy , J. Higl , P. V. F. Edelmann , F. K. Röpke
‹ Prev 1 4 5 6 7 8 10 Next ›