Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bursts from internal shocks: is it really synchrotron emission?   Within the standard internal shock scenario, synchrotron emission would
produce a spectrum with slope F(v) proportional to v^(-1/2), as immediate
consequence of the cooling timescale being shorter than the integration time.
This is in disagreement with the harder observed spectra, indicating that a
different mechanism is responsible for the burst emission. Furthermore in this
scenario pair production is expected when photons produced by inverse Compton
emission are taken into account.

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The categories of this paper are: cond-mat
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The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: eess
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph