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arXiv · 1912.10945

A nonthermal bomb explains the near-infrared superflare of Sgr A*

Eduardo M. Gutiérrez·Rodrigo Nemmen·Fabio Cafardo
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Abstract

The Galactic center supermassive black hole, Sgr A*, has experienced a strong, unprecedented flare in May 2019 when its near-infrared luminosity reached much brighter levels than ever measured. We argue that an explosive event of particle acceleration to nonthermal energies in the innermost parts of the accretion flow---a nonthermal bomb---explains the near-IR light curve. We discuss potential mechanisms that could explain this event such as magnetic reconnection and relativistic turbulence acceleration. Multiwavelength monitoring of such superflares in radio, infrared and X-rays should allow a concrete test of the nonthermal bomb model and put better constraints on the mechanism that triggered the bomb.

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Eduardo M. Gutiérrez, Rodrigo Nemmen, Fabio Cafardo. 2020-02-25. A nonthermal bomb explains the near-infrared superflare of Sgr A*. https://doi.org/10.3847/2041-8213%2Fab7998

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