Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Precision test of Hipparcos systematics towards the Hyades   We propose and apply a test that can detect any systematic errors in the
Hipparcos parallaxes towards the Hyades cluster at the level of 0.3 mas. We
show that the statistical parallax method subsumes the classical moving cluster
methods and provides more accurate and robust estimates of the distance and the
first two moments of the velocity distribution of the Hyades cluster namely,
its bulk space velocity and the velocity dispersion tensor. We predict the
parallaxes of Hyades cluster members using the common cluster space velocity
derived from the statistical parallax method and their individual Hipparcos
proper motions. We show that the parallaxes determined in this manner (pi_pm)
are consistent at the 1-sigma level with the parallaxes (pi_orb) of three
Hyades spectroscopic binary systems with orbital solutions. We find that
<(pi_pm - pi_orb)> = 0.52 +- 0.47 mas, where the error is dominated by the
errors in the orbital parallaxes. A reduction in this error would allow a test
of the systematic errors in the Hipparcos parallaxes at the 0.3 mas level. If
the Hyades distance scale is fixed by Hipparcos parallaxes, then its bulk
velocity in equatorial coordinates is (Vx,Vy,Vz) = (-5.70 +- 0.20, 45.62 +-
0.11, 5.65 +- 0.08)km/s, its velocity dispersion is 320 +- 39 m/s, and the
distance modulus to the centroid of our sample of 43 cluster members is 3.34 +-
0.02 mag.

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The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
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The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
16
The categories of this paper are: stat
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The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg