Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A nonthermal bomb explains the near-infrared superflare of Sgr A*   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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The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom
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The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
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The categories of this paper are: q-fin
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The categories of this paper are: econ
12
The categories of this paper are: nucl-th