Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of molecular hydrogen in SN 1987A   Both CO and SiO have been observed at early and late phases in SN 1987A. H_2
was predicted to form at roughly the same time as these molecules, but was not
detected at early epochs. Here we report the detection of NIR lines from H_2 at
2.12 mu and 2.40 mu in VLT/SINFONI spectra obtained between days 6489 and
10,120. The emission is concentrated to the core of the supernova in contrast
to H-alpha and approximately coincides with the [Si I]/[Fe II] emission
detected previously in the ejecta. Different excitation mechanisms and power
sources of the emission are discussed. From the nearly constant H_2
luminosities we favour excitation resulting from the 44Ti decay.

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The categories of this paper are: cond-mat
1
The categories of this paper are: cs
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
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The categories of this paper are: hep-th
23
The categories of this paper are: solv-int