Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: iPTF14yb: The First Discovery of a GRB Afterglow Independent of a
  High-Energy Trigger   We report here the discovery by the Intermediate Palomar Transient Factory
(iPTF) of iPTF14yb, a luminous ($M_{r}\approx-27.8$ mag), cosmological
(redshift 1.9733), rapidly fading optical transient. We demonstrate, based on
probabilistic arguments and a comparison with the broader population, that
iPTF14yb is the optical afterglow of the long-duration gamma-ray burst GRB
140226A. This marks the first unambiguous discovery of a GRB afterglow prior to
(and thus entirely independent of) an associated high-energy trigger. We
estimate the rate of iPTF14yb-like sources (i.e., cosmologically distant
relativistic explosions) based on iPTF observations, inferring an all-sky value
of $\Re_{\mathrm{rel}}=610$ yr$^{-1}$ (68% confidence interval of 110-2000
yr$^{-1}$). Our derived rate is consistent (within the large uncertainty) with
the all-sky rate of on-axis GRBs derived by the Swift satellite. Finally, we
briefly discuss the implications of the nondetection to date of bona fide
"orphan" afterglows (i.e., those lacking detectable high-energy emission) on
GRB beaming and the degree of baryon loading in these relativistic jets.

23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
19
The categories of this paper are: eess
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg