Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An observational asteroseismic study of the pulsating B-stars in the
  open cluster NGC 884   Recent progress in the seismic interpretation of field {\beta} Cep stars has
resulted in improvements of the physical description in the stellar structure
and evolution model computations of massive stars. Further asteroseismic
constraints can be obtained from studying ensembles of stars in a young open
cluster, which all have similar age, distance and chemical composition. We
present an observational asteroseismic study based on the discovery of numerous
multi-periodic and mono-periodic B-stars in the open cluster NGC 884. Our study
illustrates the current status of ensemble asteroseismology of a young open
cluster.

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The categories of this paper are: econ
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg