Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Rapid Merger of Binary Primordial Black Holes: an Implication for
  GW150914   We propose a new scenario for the evolution of a binary of primordial black
holes (PBHs). We consider a dynamical friction by ambient dark matter,
scattering of dark matter particles with a highly eccentric orbit besides the
standard two-body relaxation process to refill the loss cone, and interaction
between the binary and a circumbinary disk, assuming that PBHs do not
constitute the bulk of dark matter. Binary PBHs lose the energy and angular
momentum by these processes, which could be sufficiently efficient for a
typical configuration. Such a binary coalesces due to the gravitational wave
emission in a time scale much shorter than the age of the universe. We estimate
the density parameter of the resultant gravitational wave background.
Astrophysical implication concerning the formation of intermediate-mass to
supermassive black holes is also discussed.

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The categories of this paper are: cond-mat
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The categories of this paper are: hep-th
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The categories of this paper are: ao-sci
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: solv-int
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The categories of this paper are: physics
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The categories of this paper are: nucl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: bayes-an
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The categories of this paper are: cs
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The categories of this paper are: econ
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The categories of this paper are: math