Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: GWTC-2.1: Deep Extended Catalog of Compact Binary Coalescences Observed
  by LIGO and Virgo During the First Half of the Third Observing Run   The second gravitational-wave transient catalog, GWTC-2, reported on 39
compact binary coalescences observed by the Advanced LIGO and Advanced Virgo
detectors between 1 April 2019 15:00 UTC and 1 October 2019 15:00 UTC. Here, we
present GWTC-2.1, which reports on a deeper list of candidate events observed
over the same period. We analyze the final version of the strain data over this
period, which is now publicly released. We employ three matched-filter search
pipelines for candidate identification, and estimate the probability of
astrophysical origin for each candidate event. While GWTC-2 used a false alarm
rate threshold of 2 per year, we include in GWTC-2.1, 1201 candidates that pass
a false alarm rate threshold of 2 per day. We calculate the source properties
of a subset of 44 high-significance candidates that have a probability of
astrophysical origin greater than 0.5, using the default priors. Of these
candidates, 36 have been reported in GWTC-2. If the 8 additional
high-significance candidates presented here are astrophysical, the mass range
of candidate events that are unambiguously identified as binary black holes
(both objects $\geq 3M_\odot$) is increased compared to GWTC-2, with total
masses from $\sim 14M_\odot$ for GW190924_021846 to $\sim 184M_\odot$ for
GW190426_190642. The primary components of two new candidate events
(GW190403_051519 and GW190426_190642) fall in the mass gap predicted by
pair-instability supernova theory. We also expand the population of binaries
with significantly asymmetric mass ratios reported in GWTC-2 by an additional
two events ($q \lt 0.61$ and $q \lt 0.62$ at $90\%$ credibility for
GW190403_051519 and GW190917_114630 respectively), and find that 2 of the 8 new
events have effective inspiral spins $\chi_\mathrm{eff} > 0$ (at $90\%$
credibility), while no binary is consistent with $\chi_\mathrm{eff} \lt 0$ at
the same significance.

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The categories of this paper are: physics
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The categories of this paper are: supr-con
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: q-bio
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The categories of this paper are: econ
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
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The categories of this paper are: quant-ph
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The categories of this paper are: cs
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The categories of this paper are: nucl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: stat