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Related papers: Galactic Centre Threads as Nuclear MHD Waves

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We propose a model to account for the bursts from soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) in which quantum electrodynamics (QED) plays a vital role. In our theory, that we term ``fast-mode breakdown,''…

Astrophysics · Physics 2014-10-13 Jeremy S. Heyl , Lars Hernquist

For the nonthermal radio emission of the Galactic Center Arc in situ electron acceleration is imperative. The observed radio spectrum can be modeled by a transport equation for the relativistic electrons which includes particle acceleration…

Astrophysics · Physics 2009-11-10 S. Lieb , H. Lesch , G. T. Birk

A large number of supernova remnants (SNRs) in our Galaxy and galaxies nearby have been resolved in various radio bands. This radio emission is thought to be produced via synchrotron emission from electrons accelerated by the shock that the…

High Energy Astrophysical Phenomena · Physics 2016-07-27 Rodolfo Barniol Duran , Joseph F. Whitehead , Dimitrios Giannios

Multi-scale interaction between the LMC, Galactic halo, and the disk is examined with N-body simulations, and precise amplitudes of the Galactic warp excitation are obtained. The Galactic models are constructed most realistically to satisfy…

Astrophysics · Physics 2015-06-24 Toshio Tsuchiya

Magneto-hydrodynamic (MHD) turbulence is ubiquitous and a fundamental ingredient underlying many astrophysical phenomena. The multiphase nature of interstellar medium and diversity of driving mechanisms give rise to spatial variation of…

In this work we study how the turbulent component of the Galactic magnetic field (GMF) affects the propagation of ultrahigh energy heavy nuclei. We investigate first how the images of individual sources and of the supergalactic plane depend…

High Energy Astrophysical Phenomena · Physics 2015-03-19 G. Giacinti , M. Kachelriess , D. V. Semikoz , G. Sigl

Cosmological MHD simulations of galaxy cluster formation show a significant amplification of seed magnetic fields. We developed a novel method to decompose cluster magnetized turbulence into modes and showed that the fraction of the fast…

Astrophysics of Galaxies · Physics 2015-06-12 Andrey Beresnyak , Hao Xu , Hui Li , Reinhard Schlickeiser

Recent results from multi-wavelength observations of the inner few hundred pc of the Galactic center have added two new characteristics to the ISM in this unique region. One is the cosmic ray ionization rate derived from H$_3^+$…

Astrophysics of Galaxies · Physics 2019-12-25 F. Yusef-Zadeh , M. Wardle , I. Heywood , W. Cotton , M. Royster

Nuclear spirals can provide a wealth of information about the nuclear potential in disc galaxies. They are unlikely to form in nuclei with solid-body rotation, yet they are present in a majority of galactic centres. Their morphology varies…

Astrophysics · Physics 2009-11-10 Witold Maciejewski

Radio observations discovered large scale non thermal sources in the central Mpc regions of dynamically disturbed galaxy clusters (radio halos). The morphological and spectral properties of these sources suggest that the emitting electrons…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 G. Brunetti , A. Lazarian

Observations of the Milky Way and external galaxies support the idea that large-scale magnetic fields are concentrated in galactic disks, with halo magnetic fields at least an order of magnitude weaker. However, very little is known about…

Astrophysics of Galaxies · Physics 2025-03-04 Bailey Forster , Tyler J. Foster , Roland Kothes , Alex S. Hill , Jo-Anne Brown

Streams of gas and dust in the inner parsec of the Galactic center form a distinct feature known as the Minispiral, which has been studied in radio waveband as well as in the infrared wavebands. A large fraction of the Minispiral gas is…

Astrophysics of Galaxies · Physics 2015-07-03 Michal Zajacek , Vladimir Karas , Devaky Kunneriath

We present statistical analysis of diffuse Galactic synchrotron emission and polarized thermal emission from dust. Both Galactic synchrotron emission and polarized thermal emission from dust reflect statistics of magnetic field fluctuations…

Astrophysics · Physics 2008-12-12 Jungyeon Cho , A. Lazarian

We present high-pass filtered continuum images of the inner $3.5^\circ\times2.5^\circ$ of the Galactic center at 20 cm with $6.4''$ resolution. These mosaic images are taken with MeerKAT and reveal a large number of narrow filaments,…

Astrophysics of Galaxies · Physics 2022-02-09 F. Yusef-Zadeh , R. G. Arendt , M. Wardle , I. Heywood , W. D. Cotton , F. Camilo

Cosmic rays are transported out of the galaxy by diffusion and advection due to streaming along magnetic field lines and resonant scattering off self-excited MHD waves. Thus momentum is transferred to the plasma via the frozen-in waves as a…

High Energy Astrophysical Phenomena · Physics 2013-04-05 E. A. Dorfi , D. Breitschwerdt

The physical processes involved in diffusion of Galactic cosmic rays in the interstellar medium are addressed. We study the possibility that the nonlinear MHD cascade sets the power-law spectrum of turbulence which scatters charged…

Astrophysics · Physics 2008-11-26 V. S. Ptuskin , I. V. Moskalenko , F. C. Jones , A. W. Strong , V. N. Zirakashvili

On the basis of ``sticky particle'' calculations, it is argued that the gas features observed within 10 pc of the Galactic Centre-- the circumnuclear disk (CND) and the ionized gas filaments-- as well as the newly formed stars in the inner…

Astrophysics · Physics 2009-10-30 R. H. Sanders

The Galactic Center is an excellent laboratory for studying phenomena and physical processes that may be occurring in many other galactic nuclei. The Center of our Milky Way is by far the closest galactic nucleus, and observations with…

Astrophysics of Galaxies · Physics 2015-05-19 Reinhard Genzel , Frank Eisenhauer , Stefan Gillessen

We consider the generation of gravitational waves by primordial helical inverse cascade magnetohydrodynamic (MHD) turbulence produced by bubble collisions at the electroweak phase transition. We extend the previous study \cite{kgr08} by…

Several independent lines of evidence reveal that a relatively strong and highly ordered magnetic field is present throughout the Galaxy's central molecular zone (CMZ). The field within dense clouds of the central molecular zone is…

Astrophysics of Galaxies · Physics 2018-03-14 Mark R. Morris