Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Searching for gravitationally lensed gamma-ray bursts with their
  afterglows   Gamma-ray bursts (GRBs) at high redshifts are expected to be gravitationally
lensed by objects of different mass scales. Besides a single recent claim, no
lensed GRB has been detected so far by using the gamma-ray data only. In this
paper, we suggest that the multi-band afterglow data might be an efficient way
to search for lensed GRB events. Using the standard afterglow model we
calculate the characteristics of the lensed afterglow lightcurves under the
assumption of two popular analytic lens models: point mass and Singular
Isothermal Sphere (SIS) model. In particular, when different lensed images
cannot be resolved, their signals would be superimposed together with a given
time delay. In this case, the X-ray afterglows are likely to contain several
X-ray flares of similar width in linear scale and similar spectrum, and the
optical afterglow lightcurve will show rebrightening signatures. Since the
lightcurves from the image arriving later would be compressed and deformed in
the logarithmic time scale, the larger time delay (i.e. the larger mass of the
lens), the easier is to identify the lensing effect. We analyzed the archival
data of optical afterglows and found one potential candidate of the lensed GRB
(130831A) with time delay $\sim$500 s, however, observations of this event in
gamma-ray and X-ray band seem not to support the lensing hypothesis. In the
future, with the cooperation of the all-sky monitoring gamma-ray detectors and
multi-band sky survey projects, our method proposed in this paper would be more
efficient in searching for strongly lensed GRBs.

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The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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The categories of this paper are: dg-ga
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The categories of this paper are: mtrl-th
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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
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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: funct-an
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The categories of this paper are: q-fin
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The categories of this paper are: alg-geom
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The categories of this paper are: stat
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The categories of this paper are: solv-int
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The categories of this paper are: eess