Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Basic parameters and properties of the rapidly rotating magnetic helium
  strong B star HR7355   The spectral and magnetic properties and variability of the B2Vnp
emission-line magnetosphere star HR7355 were analyzed. The object rotates at
almost 90% of the critical value, meaning it is a magnetic star for which
oblateness and gravity darkening effects cannot be ignored any longer. A
detailed modeling of the photospheric parameters indicate that the star is
significantly cooler than suggested by the B2 spectral type, with T_eff=17500K
atypically cool for a star with a helium enriched surface. The spectroscopic
variability of helium and metal lines due to the photospheric abundance pattern
is far more complex than a largely dipolar, oblique magnetic field of about 11
to 12kG may suggest. Doppler imaging shows that globally the most He enriched
areas coincide with the magnetic poles and metal enriched areas with the
magnetic equator. While most of the stellar surface is helium enriched with
respect to the solar value, some isolated patches are depleted. The stellar
wind in the circumstellar environment is governed by the magnetic field, i.e.
the stellar magnetosphere is rigidly corotating with the star. The
magnetosphere of HR7355 is similar to the well known \sigma Ori E: the gas
trapped in the magnetospheric clouds is fairly dense, and at the limit to being
optically thick in the hydrogen emission. Apart from a different magnetic
obliquity, HR7355 and the more recently identified HR5907 have virtually
identical stellar and magnetic parameters.

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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
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The categories of this paper are: hep-th
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
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The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: nlin
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The categories of this paper are: chem-ph
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The categories of this paper are: math
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The categories of this paper are: eess
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The categories of this paper are: atom-ph