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arXiv 2001.118272020-01-31astro-ph.GA

Galactic Centre Threads as Nuclear MHD Waves

Yoshiaki Sofue

备注：: 6 pages, 8 figures, PASJ Letters in press
DOI：: 10.1093/pasj/psaa011

英文摘要：

Propagation of fast-mode magnetohydrodynamic (MHD) compression waves is traced in the Galactic Center with a poloidal magnetic cylinder. MHD waves ejected from the nucleus are reflected and guided along the magnetic field, exhibiting vertically stretched fronts. The radio threads and non-thermal filaments are explained as due to tangential views of the waves driven by sporadic activity in Sgr A$^*$, or by multiple supernovae. In the latter case, the threads could be extremely deformed relics of old SNRs exploded in the nucleus.

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