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Supernovae are known to be the dominant energy source for driving turbulence in the interstellar medium. Yet, their effect on magnetic field amplification in spiral galaxies is still poorly understood. Analytical models based on the…

星系天体物理 · 物理学 2010-01-29 Oliver Gressel

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…

天体物理学 · 物理学 2009-10-30 Kari Enqvist

Torsion effects, including a spin precession in the torsion field, are considered. Some properties of neutrinos in cosmology are discussed. In the framework of Trautman's cosmological model with torsion estimated is a specific angular…

天体物理学 · 物理学 2009-10-31 M. L. Fil'chenkov

We report first results of first global galactic-scale CR-MHD simulations of cosmic-ray-driven dynamo. We investigate the dynamics of magnetized interstellar medium (ISM), which is dynamically coupled with the cosmic-ray (CR) gas. We assume…

星系天体物理 · 物理学 2009-11-05 Michał Hanasz , Dominik Wóltański , Kacper Kowalik

Observations indicate that intergalactic magnetic fields have amplitudes of the order of $\sim 10^{-6}$ G and are uniform on scales of $\sim 10$ kpc. Despite their wide presence in the Universe, their origin remains an open issue. Even by…

广义相对论与量子宇宙学 · 物理学 2022-10-26 S. Capozziello , A. Carleo , G. Lambiase

We show that it is possible to construct a consistent model describing a current-carrying cosmic string endowed with torsion. The torsion contribution to the gravitational force and geodesics of a test-particle moving around the SCCS are…

高能物理 - 理论 · 物理学 2007-05-23 C. N. Ferreira , H. J. Mosquera-Cuesta , L. C. Garcia de Andrade

We present a model for the seeding and evolution of magnetic fields in galaxies by supernovae (SN). SN explosions during galaxy assembly provide seed fields, which are subsequently amplified by compression, shear flows and random motions.…

星系天体物理 · 物理学 2017-01-11 Alexander M. Beck , Klaus Dolag

We study the effects of the magnetic field on the dynamics of non-rotating stellar cores by performing two-dimensional (2D), magnetohydrodynamics (MHD) simulations. To this end, we have updated our neutrino-radiation-hydrodynamics supernova…

高能天体物理现象 · 物理学 2020-10-07 Jin Matsumoto , Tomoya Takiwaki , Kei Kotake , Yuta Asahina , Hiroyuki R. Takahashi

Magnetic induction was first proposed as a planetary heating mechanism by Sonett and Colburn in 1968, in recent years this theory has lost favor as a plausible source of heating in the early solar system. However, new models of…

地球与行星天体物理 · 物理学 2017-07-25 Daniella N. DellaGiustina

We review the present theoretical and numerical understanding of magnetic field amplification in cosmic large-scale structure, on length scales of galaxy clusters and beyond. Structure formation drives compression and turbulence, which…

宇宙学与河外天体物理 · 物理学 2018-11-28 J. Donnert , F. Vazza , M. Brüggen , J. ZuHone

Despite their ubiquity, the origin of cosmic magnetic fields remains unknown. Various mechanisms have been proposed for their existence including primordial fields generated by inflation, or amplification and injection by compact…

宇宙学与河外天体物理 · 物理学 2019-01-23 Harley Katz , Sergio Martin-Alvarez , Julien Devriendt , Adrianne Slyz , Taysun Kimm

We explore the amplification of magnetic seed fields during the formation of the first stars and galaxies. During gravitational collapse, turbulence is created from accretion shocks, which may act to amplify weak magnetic fields in the…

宇宙学与河外天体物理 · 物理学 2015-05-18 Dominik R. G. Schleicher , Robi Banerjee , Sharanya Sur , Tigran G. Arshakian , Ralf S. Klessen , Rainer Beck , Marco Spaans

If cosmic magnetic fields are indeed produced during inflation, they are likely to be correlated with the scalar metric perturbations that are responsible for the Cosmic Microwave Background anisotropies and Large Scale Structure. Within an…

宇宙学与河外天体物理 · 物理学 2013-05-30 Rajeev Kumar Jain , Martin S. Sloth

Magnetic fields are present on all scales in the Universe. While we understand the processes which amplify the fields fairly well, we do not have a "natural" mechanism to generate the small initial seed fields. By using fully relativistic…

宇宙学与河外天体物理 · 物理学 2014-09-18 Ellie Nalson , Adam J. Christopherson , Karim A. Malik

The galactic magnetic field is commonly supposed to be due to a dynamo acting on some large scale seed field. A major difficulty with this idea is that estimates of reasonable seed field strengths tend to be quite low, on the order of…

天体物理学 · 物理学 2007-05-23 Ethan T. Vishniac

Magnetic fields are ubiquitous in the Universe. Extragalactic disks, halos and clusters have consistently been shown, via diffuse radio-synchrotron emission and Faraday rotation measurements, to exhibit magnetic field strengths ranging from…

Low-mass galaxies radio observations show in many cases surprisingly high levels of magnetic field. The mass and kinematics of such objects do not favour the development of effective large-scale dynamo action. We attempted to check if the…

星系天体物理 · 物理学 2018-03-14 Hubert Siejkowski , Marian Soida , Krzysztof T. Chyzy

The origin of cosmic magnetic fields is an unsolved problem and magnetogenesis could have occurred in the early Universe. We study the evolution of such primordial magnetic fields across the cosmological recombination epoch via 3D…

宇宙学与河外天体物理 · 物理学 2018-07-25 Pranjal Trivedi , Johannes Reppin , Jens Chluba , Robi Banerjee

We study the evolution of phase-transition-generated cosmic magnetic fields coupled to the primeval cosmic plasma in turbulent and viscous free-streaming regimes. The evolution laws for the magnetic energy density and correlation length,…

宇宙学与河外天体物理 · 物理学 2015-06-15 Leonardo Campanelli

Based on the new findings on the turbulent dynamo in \citet{XL16}, we examine the magnetic field amplification in the context of supernova remnants. Due to the strong ion-neutral collisional damping in the weakly-ionized interstellar…

高能天体物理现象 · 物理学 2017-12-13 Siyao Xu , Alex Lazarian