Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Swift unveils the orbital period of IGR J18214-1318   We analysed 13 years of the Neil Gehrels Swift Observatory survey data
collected on the High Mass X-ray Binary IGR J18214-1318. Performing the timing
analysis we detected a periodic signal of 5.42 d. From the companion star
characteristics we derived an average orbital separation of $\sim 41 \rm
R_{\odot}\simeq 2 R_{\star}$. The spectral type of the companion star (O9) and
the tight orbital separation suggest that IGR~J18214-1318 is a wind accreting
source with eccentricity lower than 0.17. The intensity profile folded at the
orbital period shows a deep minimum compatible with an eclipse of the source by
the companion star. In addition, we report on the broad-band 0.6--100 keV
spectrum using data from XMM-Newton, NuSTAR, and Swift, applying
self-consistent physical models. We find that the spectrum is well fitted
either by a pure thermal Comptonization component, or, assuming that the source
is a neutron star accreting above the critical regime, by a combined thermal
and bulk-motion Comptonization model. In both cases, the presence of a local
neutral absorption (possibly related to the thick wind of the companion star)
is required.

27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
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The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
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The categories of this paper are: stat
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
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The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
3
The categories of this paper are: physics