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arXiv · 1608.05904

Evolution of Supernova Remnants near the Galactic Center

Almog Yalinewich·Tsvi Piran·Re'em Sari
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Abstract

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 center propagate into a wind swept environment with a velocity away from the galactic center, and a graded density profile. This causes these SNRs to be non - spherical, and to evolve faster than their galactic counterparts. We develop an analytic theory for the evolution of explosions within a stellar wind, and verify it using a hydrodynamic code. We show that such explosions can evolve in one of three possible morphologies. Using these results we discuss the association between the two SNRs (SGR East and SGR A's bipolar radio/X-ray Lobes) and the two neutron stars (the cannonball and SGR J1745-2900) near the galactic center. We show that, given the morphologies of the SNR and positions of the neutron stars, the only possible association is between SGR A's bipolar radio/X-ray Lobes and SGR J1745-2900. The compact object created in the explosion of SGR East remains undetected, and the SNR of the supernova that created the cannonball has already disappeared.

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Almog Yalinewich, Tsvi Piran, Re'em Sari. 2016-08-21. Evolution of Supernova Remnants near the Galactic Center. https://doi.org/10.3847/1538-4357%2Faa5d0f

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