Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The lowest metallicity type II supernova from the highest mass
  red-supergiant progenitor   Red supergiants have been confirmed as the progenitor stars of the majority
of hydrogen-rich type II supernovae. However, while such stars are observed
with masses >25M$_\odot$, detections of >18M$_\odot$ progenitors remain
elusive. Red supergiants are also expected to form at all metallicities, but
discoveries of explosions from low-metallicity progenitors are scarce. Here, we
report observations of the type II supernova, SN 2015bs, for which we infer a
progenitor metallicity of $\leq$0.1Z$_\odot$ from comparison to
photospheric-phase spectral models, and a Zero Age Main-Sequence mass of
17-25M$_\odot$ through comparison to nebular-phase spectral models. SN 2015bs
displays a normal 'plateau' light-curve morphology, and typical spectral
properties, implying a red supergiant progenitor. This is the first example of
such a high mass progenitor for a 'normal' type II supernova, suggesting a link
between high mass red supergiant explosions and low-metallicity progenitors.

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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc
1
The categories of this paper are: cs
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The categories of this paper are: hep-ex
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The categories of this paper are: funct-an
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The categories of this paper are: math-ph
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
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The categories of this paper are: physics
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The categories of this paper are: econ
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The categories of this paper are: stat
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The categories of this paper are: cmp-lg
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The categories of this paper are: dg-ga