Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two SMC Symbiotic stars undergoing steady hydrogen burning   Two symbiotic stars in the Small Magellanic Cloud (SMC), Lin 358 and SMC 3,
have been supersoft X-ray sources (SSS) for more than 10 years. We fit
atmospheric and nebular models to their X-ray, optical and UV spectra obtained
at different epochs. The X-ray spectra are extremely soft, and appear to be
emitted by the white dwarf atmosphere and not by the nebula like in some other
symbiotics. The white dwarf of SMC 3, the hottest of the two sources, had a
constant effective temperature ~500,000 K at various epochs during 12 years. No
nova-like outbursts of these systems have been recorded in the last 50 years,
despite continuous optical monitoring of the SMC, and there are no indications
of cooling of the white dwarf, expected after a thermonuclear flash. The
bolometric luminosity of this system in March of 2003 was more than an order of
magnitude lower than three years later, however the time of the observation is
consistent with a partial eclipse of the white dwarf, previously found in ROSAT
and optical observations. The red giant wind is either very asymmetric or very
clumpy. The conpact object of Lin 358 has been at T>~180,000 K since 1993,
perhaps with a moderate increase. Atmospheric fits are obtained with log(g)>=9,
appropriate only for WD mass >1.18 M(sol). The two systems are probably
accreting and burning hydrogen steadily at the high rate required for type Ia
supernova progenitors.

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The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
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The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: nlin
10
The categories of this paper are: q-bio
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The categories of this paper are: q-fin