Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unbound Debris Streams and Remnants Resulting From the Tidal Disruptions
  of Stars by Supermassive Black Holes   The kinetic energy of a star in orbit about a supermassive black hole is a
significant fraction of its rest mass energy when its periapse is comparable to
its tidal radius. Upon its destruction, a fraction of this energy is extracted
and injected into the stellar debris, half of which becomes unbound from the
black hole, with the fastest material moving at $\sim 0.03 c$. In this paper,
we present a formalism for determining the fate of these unbound debris streams
(UDSs) as they depart from the black hole and interact with the surrounding
gas. As the density and velocity varies along the length of a UDS, we find that
hydrodynamical drag quickly shapes UDSs into loop-like structures, with the
densest portions of the streams leading portions of lower density. As UDSs
travel outwards, their drag against the ISM increases quadratically with
distance, which causes UDSs to deposit their momentum and energy into the
ambient medium before the surrounding shocked ISM has a chance to cool. This
sudden injection of $\sim 10^{50}$ erg into the ambient medium generates a
Sedov-like unbound debris remnant (UDR) that mimics supernova remnants (SNRs)
in energetics and appearance, accelerates particles which will produce cosmic
rays and synchrotron emission, and provides momentum feedback into the
molecular clouds surrounding a black hole. We estimate that a few of these UDRs
might be present within a couple degrees of the Galactic Center masquerading as
SNRs, and that the UDR scenario is a plausible explanation for Sgr A East.

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The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
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The categories of this paper are: cs
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The categories of this paper are: math
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
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The categories of this paper are: stat
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The categories of this paper are: solv-int
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The categories of this paper are: nlin