Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Implications of aging in young supernovae   We present here the combined radio spectrum from the Giant Metrewave Radio
Telescope (GMRT) and Very Large Array (VLA) of type-IIb SN 1993J (age 11 years)
and a type-Ic SN 2003bg (age 1 year). In SN 1993J, we find a break in the
spectrum at 4 GHz and associate it with Synchrotron cooling break. Hence, we
determine the magnetic field independent of equipartition assumption between
relativistic electrons and magnetic energy. We also see a hint of break in the
spectrum of SN 2003bg between 22-40 GHz. The spectrum of SN 2003bg is well
described by the synchrotron self absorption model.

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The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: eess
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The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: cs
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The categories of this paper are: cond-mat
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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-alg
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat