Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Metal-Rich SX Phe stars in the Kepler Field   A spectroscopic and photometric analysis has been carried out for thirty-two
candidate SX_Phe variable blue straggler stars in the Kepler-field (Balona &
Nemec 2012). Radial velocities (RVs), space motions (U,V,W), projected rotation
velocities (v sin i), spectral types, and atmospheric characteristics (T_eff,
log g, [Fe/H], xi_t, zeta_RT, etc.) are presented for 30 of the 32 stars.
Although several stars are metal-weak with extreme halo orbits, the mean [Fe/H]
of the sample is near solar, thus the stars are more metal-rich than expected
for a typical sample of Pop.II stars, and more like halo metal-rich A-type
stars (Perry 1969). Two thirds of the stars are fast rotators with v sin i > 50
km/s, including four stars with v sin i > 200 km/s. Three of the stars have
(negative) RVs > 250 km/s, five have retrograde space motions, and 21 have
total speeds (relative to the LSR) > 400 km/s. All but one of the 30 stars have
positions in a Toomre diagram consistent with the kinematics of bona fide halo
stars (the exception being a thick-disk star). Observed Roemer time delays,
pulsation frequency modulations and light curves suggest that at least one
third of the stars are in binary (or triple) systems with orbital periods
ranging from 2.3 days to more than four years.

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The categories of this paper are: gr-qc
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The categories of this paper are: q-fin
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The categories of this paper are: cmp-lg
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The categories of this paper are: chao-dyn
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The categories of this paper are: cond-mat
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The categories of this paper are: math
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The categories of this paper are: acc-phys
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The categories of this paper are: physics
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The categories of this paper are: econ
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The categories of this paper are: quant-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: cs
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-ph
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The categories of this paper are: funct-an