中文
相关论文

相关论文: Superbubbles, Galactic Dynamos and the Spike Insta…

200 篇论文

In previous galactic dynamo theories of the origin of the magnetic field in our galaxy, the subject of flux-freezing has been omitted. As a consequence, the equation of mass flow has generally also been omitted, particularly in the halo…

星系天体物理 · 物理学 2015-12-23 Russell M. Kulsrud

The possibility of the magnetic flux expulsion from the Galaxy in the superbubble (SB) explosions, important for the Alpha-Omega dynamo, is considered. Special emphasis is put on the investigation of the downsliding of the matter from the…

天体物理学 · 物理学 2009-10-31 R. R. Rafikov , R. M. Kulsrud

The current understanding of astrophysical magnetic fields is reviewed, focusing on their generation and maintenance by turbulence. In the astrophysical context this generation is usually explained by a self-excited dynamo, which involves…

天体物理学 · 物理学 2008-11-26 Axel Brandenburg , Kandaswamy Subramanian

We review the literature concerning how the cosmic magnetic fields pervading nearly all galaxies actually got started. some observational evidence involves the chemical abundance of the light elements Be and B, while another one is based on…

天体物理学 · 物理学 2009-11-13 Russell M. Kulsrud , Ellen G. Zweibel

The origin and sustenance of large scale galactic magnetic fields has been a long standing and controversial astrophysical problem. Here an alternative to the ``standard'' $\a-\Omega$ mean field dynamo and primordial theories is pursued.…

天体物理学 · 物理学 2009-10-30 Eric G. Blackman

A variety of observations suggest that magnetic fields are present in all galaxies and galaxy clusters. These fields are characterized by a modest strength (10^{-7}-10^{-5} G) and huge spatial scale (~Mpc). It is generally assumed that…

天体物理学 · 物理学 2008-11-26 Lawrence M. Widrow

The magnetic fields of spiral galaxies are so strong that they cannot be primordial. Their typical values are over one billion times higher than any value predicted for the early Universe. Explaining this immense growth and incorporating it…

Large-scale magnetic fields in galaxies are thought to be generated by a turbulent dynamo. However the same turbulence also leads to a small-scale dynamo which generates magnetic noise at a more rapid rate. The efficiency of the large-scale…

天体物理学 · 物理学 2020-11-25 K. Subramanian

The nature and origin of turbulence and magnetic fields in the intergalactic space are important problems that are yet to be understood. We propose a scenario in which turbulent flow motions are induced via the cascade of the vorticity…

天体物理学 · 物理学 2009-11-13 Dongsu Ryu , Hyesung Kang , Jungyeon Cho , Santabrata Das

Interstellar magnetic fields in elliptical galaxies are assumed to have their origin in stellar fields that accompany normal mass loss from an evolving population of old stars. The seed fields are amplified by interstellar turbulence driven…

天体物理学 · 物理学 2009-10-30 William G. Mathews , Fabrizio Brighenti

Dynamos in astrophysical disks are usually explained in terms of the standard alpha-omega mean field dynamo model where the local helicity generates a radial field component from an azimuthal field. The subsequent shearing of the radial…

天体物理学 · 物理学 2015-06-24 Ethan T. Vishniac

There is growing evidence for star formation inside outflows of active galactic nuclei (AGNs). The formed stars are injected into bulges and give rise to perturbation of bulges. In this paper, we investigate the issues of non-rotating,…

星系天体物理 · 物理学 2024-12-25 Yue-Chang Peng , Jian-Min Wang , Yu Zhao , Luis C. Ho

Spiral galaxies, including the Milky Way, have large-scale magnetic fields with significant energy densities. The dominant theory attributes these magnetic fields to a large-scale dynamo. We review the current status of dynamo theory and…

星系天体物理 · 物理学 2023-08-31 Axel Brandenburg , Evangelia Ntormousi

A magnetic field dynamo in the inner regions of the accretion disk surrounding the supermassive black holes in AGNs may be the mechanism for the generation of magnetic fields in galaxies and in extragalactic space. We argue that the two…

天体物理学 · 物理学 2009-01-19 Vladimir I. Pariev , Stirling A. Colgate

Mean-field galactic dynamo theory is the leading theory to explain the prevalence of regular magnetic fields in spiral galaxies, but its systematic comparison with observations is still incomplete and fragmentary. Here we compare…

星系天体物理 · 物理学 2016-12-14 Luke Chamandy , Anvar Shukurov , A. Russ Taylor

We perform hydrodynamical simulations of a young galactic disc embedded in a hot gaseous halo using parameters typical for Lyman break galaxies (LBGs). We take into account the (static) gravitational potentials due to a dark matter halo, a…

宇宙学与河外天体物理 · 物理学 2015-06-16 Wolfgang von Glasow , Martin Krause , Jesper Sommer-Larsen , Andreas Burkert

Astrophysical objects with negligible resistivity are often threaded by large scale magnetic fields. The generation of these fields is somewhat mysterious, since a magnetic field in a perfectly conducting fluid cannot change the flux…

天体物理学 · 物理学 2007-05-23 E. T. Vishniac , A. Lazarian , J. Cho

Supernovae are the dominant energy source for driving turbulence within the interstellar plasma. Until recently, their effects on magnetic field amplification in disk galaxies remained a matter of speculation. By means of self-consistent…

天体物理学 · 物理学 2009-11-13 Oliver Gressel , Udo Ziegler , Detlef Elstner , Günther Rüdiger

Natural dynamos such as planets and stars generate global scale magnetic field despite the inferred presence of small scale turbulence. Such systems are known as large scale dynamos and are typically driven by convection and influenced by…

流体动力学 · 物理学 2022-02-24 Ming Yan , Michael A. Calkins

Solar, stellar and galactic large-scale magnetic fields are originated due to a combined action of non-uniform (differential) rotation and helical motions of plasma via mean-field dynamos. Usually, nonlinear mean-field dynamo theories take…

太阳与恒星天体物理 · 物理学 2024-04-19 I. Rogachevskii , N. Kleeorin
‹ 上一页 1 2 3 10 下一页 ›