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Related papers: Galactic Centre Threads as Nuclear MHD Waves

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Recent results from the HESS gamma ray telescope have shown the presence of both a diffuse, extended, flux of gamma rays above ~0.4 TeV and discrete sources in and near the Galactic Centre. Here, we put forward a possible explanation in…

Astrophysics · Physics 2009-06-23 A. D. Erlykin , A. W. Wolfendale

Nonthermal radio emission in the galactic center reveals a number of vertical structures across the galactic plane, which are attributed to poloidal magnetic field and/or energetic outflow. Thermal radio emission comprises star forming…

Astrophysics · Physics 2015-06-24 Yoshiaki Sofue

Cosmic rays (CRs) are transported out of the galaxy by diffusion and advection due to streaming along magnetic field lines and resonant scattering off self-excited Magneto-Hydro-Dynamic (MHD) waves. Thus momentum is transferred to the…

Astrophysics of Galaxies · Physics 2019-10-02 E. A. Dorfi , D. Steiner , F. Ragossnig , D. Breitschwerdt

The Galactic center (GC) is a dense and chaotic region filled with unusual sources, such as intense star forming regions, dense star clusters, nonthermal radio filaments, and a massive black hole. The proximity of the GC region makes it an…

Astrophysics · Physics 2016-06-22 Casey James Law

Gravitational waves (GW) propagating through a magnetised plasma excite low-frequency magnetohydrodynamic (MHD) waves. In this paper we investigate whether these waves can produce observable radio emission at higher frequencies by…

Astrophysics · Physics 2009-11-11 Joachim Moortgat , Jan Kuijpers

The circumnuclear disk (CND) of the Galactic Center is exposed to many energetic phenomena coming from the supermassive black hole Sgr A* and stellar activities. These energetic activities can affect the chemical composition in the CND by…

Solar flares involve the sudden release of magnetic energy in the solar corona. Accelerated nonthermal electrons have often been invoked as the primary means for transporting the bulk of the released energy to the lower solar atmosphere.…

Solar and Stellar Astrophysics · Physics 2019-02-20 Sijie Yu , Bin Chen

The Fermi satellite discovery of the gamma-ray emitting bubbles extending 50 deg (10 kpc) from the Galactic Centre has revitalized earlier claims that our Galaxy has undergone an explosive episode in the recent past. We now explore a new…

Astrophysics of Galaxies · Physics 2015-06-17 Joss Bland-Hawthorn , Phil Maloney , Ralph Sutherland , Greg Madsen

Understanding our Galactic Center is easier with insights from nearby galactic nuclei. Both the star formation activity in nuclear gas disks, driven by bars and nuclear bars, and the fueling of low-luminosity AGN, followed by feedback of…

Astrophysics of Galaxies · Physics 2017-02-22 F. Combes

Supernovae near the galactic center evolve differently from regular galactic supernovae. This is mainly due to the environment into which the supernova remnants propagate. Instead of a static, uniform density medium, SNRs near the galactic…

High Energy Astrophysical Phenomena · Physics 2017-03-29 Almog Yalinewich , Tsvi Piran , Re'em Sari

Radio relics in galaxy clusters are extended synchrotron sources produced by cosmic-ray electrons in the $\mu$G magnetic field. Many relics are found in the cluster periphery and have a cluster-centric, narrow arc-like shape, which suggests…

High Energy Astrophysical Phenomena · Physics 2021-06-23 John A. ZuHone , Maxim Markevitch , Rainer Weinberger , Paul Nulsen , Kristian Ehlert

Within a few parsecs around the central Black Hole Sgr A*, chemistry in the dense molecular cloud material of the circumnuclear disk (CND) can be affected by many energetic phenomena such as high UV-flux from the massive central star…

We present magnetohydrodynamic simulations of a jet-wind interaction in a galaxy cluster and the radio to gamma-ray and the neutrino emissions from this "head-tail galaxy". Our simulation follows the evolution of cosmic-ray (CR) particle…

High Energy Astrophysical Phenomena · Physics 2023-07-12 Takumi Ohmura , Katsuaki Asano , Kosuke Nishiwaki , Mami Machida , Haruka Sakemi

Small-scale, cyclic, transverse motions of plasma threads are usually seen in solar prominences, which are often interpreted as magnetohydrodynamic (MHD) waves. Here, we observed small-scale decayless transverse oscillations in a quiescent…

Solar and Stellar Astrophysics · Physics 2022-01-20 Dong Li , Jianchao Xue , Ding Yuan , Zongjun Ning

The magnetic structure in the Galactic disk, the Galactic center and the Galactic halo can be delineated more clearly than ever before. In the Galactic disk, the magnetic structure has been revealed by starlight polarization within 2 or 3…

Astrophysics of Galaxies · Physics 2009-11-13 J. L. Han

Multi-frequency, polarimetric VLA observations of the non-thermal filaments (NTF's), G0.08+0.15, and G359.96+0.09, also known as the Northern and Southern Threads are presented at 20, 6, 3.6 and 2 cm, with high enough spatial resolution to…

Astrophysics · Physics 2009-10-31 Cornelia C. Lang , Mark Morris , Luis Echevarria

The tidal disruption of a star by a supermassive black hole is expected to lead to a short bright flare followed by an extended period of low-level emission. Existing models of the late-time accretion of the stellar debris via a thin disk…

Astrophysics · Physics 2009-11-07 Kristen Menou , Eliot Quataert

High-velocity atomic clouds in the Galactic center have attracted significant attention due to their enigmatic formation process, which is potentially linked to the starburst or supermassive black hole activities in the region. Further, the…

Astrophysics of Galaxies · Physics 2023-12-27 Mengfei Zhang , Miao Li

This paper reports the diffuse X-ray features around the Galactic center observed with Chandra. We confirm the ASCA and Ginga discoveries of the large-scale thin-thermal plasma with strong lines in the Galactic center region. In addition,…

In an X-ray binary system, the companion star feeds the compact neutron star with plasma materials via accretions. The spinning neutron star is likely covered with a thin "magnetized ocean" and may support {\it magnetohydrodynamic (MHD)…

Astrophysics · Physics 2009-11-10 Yu-Qing Lou