Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observations of bright stars with AstroSat Soft X-ray Telescope   We present observations of four bright stars observed with the AstroSat Soft
X-ray Telescope (SXT). Visible light from bright stars like these can leak
through the very thin filter in front of the CCD in the focal plane CCD camera
of the SXT and thus making the extraction of X-ray events difficult. Here, we
show how to extract the X-ray events without contamination by the visible
light. The procedure applied to four bright stars here demonstrates how
reliable X-ray information can be derived in such cases. The sample of bright
stars studied here consists of two A spectral types (HIP 19265, HIP 88580), one
G/K Giant (Capella), and a nearby M-type dwarf (HIP 23309). No X-ray emission
is observed from the A-type stars, as expected. X-ray spectra of Capella and
HIP 23309 are derived and modeled here, and compared with the previous X-ray
observations of these stars to show the reliability of the method used. We find
that optical light can start to leak in the very soft energy bands below 0.5
keV for stars with V=8 mag. In the process, we present the first X-ray spectrum
of HIP 23309.

27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
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The categories of this paper are: eess
10
The categories of this paper are: q-bio
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The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
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The categories of this paper are: stat
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The categories of this paper are: hep-th
2
The categories of this paper are: math
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con