Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: SNR 0104-72.3: A remnant of Type Ia Supernova in a Star-forming region?   We report our 110 ks Chandra observations of the supernova remnant (SNR)
0104-72.3 in the Small Magellanic Cloud (SMC). The X-ray morphology shows two
prominent lobes along the northwest-southeast direction and a soft faint arc in
the east. Previous low resolution X-ray images attributed the unresolved
emission from the southeastern lobe to a Be/X-ray star. Our high resolution
Chandra data clearly shows that this emission is diffuse, shock-heated plasma,
with negligible X-ray emission from the Be star. The eastern arc is
positionally coincident with a filament seen in optical and infrared
observations. Its X-ray spectrum is well fit by plasma of normal SMC
abundances, suggesting that it is from shocked ambient gas. The X-ray spectra
of the lobes show overabundant Fe, which is interpreted as emission from the
reverse-shocked Fe-rich ejecta. The overall spectral characteristics of the
lobes and the arc are similar to those of Type Ia SNRs, and we propose that SNR
0104-72.3 is the first case for a robust candidate Type Ia SNR in the SMC. On
the other hand, the remnant appears to be interacting with dense clouds toward
the east and to be associated with a nearby star-forming region. These features
are unusual for a standard Type Ia SNR. Our results suggest an intriguing
possibility that the progenitor of SNR 0104-72.3 might have been a white dwarf
of a relatively young population.

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The categories of this paper are: hep-th
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The categories of this paper are: stat
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The categories of this paper are: physics
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The categories of this paper are: dg-ga
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The categories of this paper are: q-bio
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: patt-sol
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The categories of this paper are: eess
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: econ
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph