Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: NGC 2770 - a supernova Ib factory?   NGC 2770 has been the host of three supernovae of Type Ib during the last 10
years, SN 1999eh, SN 2007uy and SN 2008D. SN 2008D attracted special attention
due to the serendipitous discovery of an associated X-ray transient. In this
paper, we study the properties of NGC 2770 and specifically the three SN sites
to investigate whether this galaxy is in any way peculiar to cause a high
frequency of SNe Ib. We model the global SED of the galaxy from broadband data
and derive a star-formation and SN rate comparable to the values of the Milky
Way. We further study the galaxy using longslit spectroscopy covering the major
axis and the three SN sites. From the spectroscopic study we find subsolar
metallicities for the SN sites, a high extinction and a moderate star-formation
rate. In a high resolution spectrum, we also detect diffuse interstellar bands
in the line-of-sight towards SN 2008. A comparison of NGC 2770 to the global
properties of a galaxy sample with high SN occurance (at least 3 SN in the last
100 years) suggests that NGC 2770 is not particularly destined to produce such
an enhancement of observed SNe observed. Its properties are also very different
from gamma-ray burst host galaxies. Statistical considerations on SN Ib
detection rates give a probability of ~1.5% to find a galaxy with three Ib SNe
detected in 10 years. The high number of rare Ib SNe in this galaxy is
therefore likely to be a coincidence rather than special properties of the
galaxy itself. NGC 2770 has a small irregular companion, NGC 2770B, which is
highly starforming, has a very low mass and one of the lowest metallicities
detected in the nearby universe as derived from longslit spectroscopy. In the
most metal poor part, we even detect Wolf-Rayet features, against the current
models of WR stars which require high metallicities.

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The categories of this paper are: stat
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: econ
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The categories of this paper are: hep-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: cmp-lg
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The categories of this paper are: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: cond-mat
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The categories of this paper are: q-fin
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The categories of this paper are: plasm-ph
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The categories of this paper are: funct-an
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The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
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The categories of this paper are: q-bio