Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Fast Radio Burst discovered in FAST drift scan survey   We report the discovery of a highly dispersed fast radio burst, FRB~181123,
from an analysis of $\sim$1500~hr of drift-scan survey data taken using the
Five-hundred-meter Aperture Spherical radio Telescope (FAST). The pulse has
three distinct emission components, which vary with frequency across our
1.0--1.5~GHz observing band. We measure the peak flux density to be $>0.065$~Jy
and the corresponding fluence $>0.2$~Jy~ms. Based on the observed dispersion
measure of 1812~cm$^{-3}$~pc, we infer a redshift of $\sim 1.9$. From this, we
estimate the peak luminosity and isotropic energy to be $\lesssim
2\times10^{43}$~erg~s$^{-1}$ and $\lesssim 2\times10^{40}$~erg, respectively.
With only one FRB from the survey detected so far, our constraints on the event
rate are limited. We derive a 95\% confidence lower limit for the event rate of
900 FRBs per day for FRBs with fluences $>0.025$~Jy~ms. We performed follow-up
observations of the source with FAST for four hours and have not found a
repeated burst. We discuss the implications of this discovery for our
understanding of the physical mechanisms of FRBs.

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The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
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The categories of this paper are: stat
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The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th