Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hyperflares of SGRs as an engine for millisecond extragalactic radio
  bursts   We propose that the strong millisecond extragalactic radio burst (mERB)
discovered by Lorimer et al. (2007) may be related to a hyperflare from an
extragalactic soft gamma-ray repeater. The expected rate of such hyperflares,
$\sim$ 20 - 100 d$^{-1}$ Gpc$^{-3}$, is in good correspondence with the value
estimated by Lorimer et al. The possible mechanism of radio emission can be
related to the tearing mode instability in the magnetar magnetosphere as
discussed by Lyutikov (2002), and can produce the radio flux corresponding to
the observed $\sim$ 30 Jy from the mERB using a simple scaling of the burst
energy.

15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int