Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evidences for two Gamma-Ray Burst afterglow emission regimes   We applied cosmological and absorption corrections to the X-ray and optical
afterglow fluxes of a sample of Gamma-Ray Burst sources of known distance. We
find a good correlation in X-rays and that the GRBs in our sample form two well
defined classes. We tentatively interpret them as radiative and adiabatic
afterglow behaviours in the framework of the fireball model for GRBs. We do not
observe this correlation at optical wavelengths. This discrepancy with the
model may be due to the absorption in the source vicinity.

20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph