J/AJ/150/141 UrHip Proper Motion Catalog (Frouard+, 2015)
UrHip Proper Motion Catalog.
Frouard J., Dorland B.N., Makarov V.V., Zacharias N., Finch C.T.
<Astron. J. 150, 141 (2015)>
=2015AJ....150..141F 2015AJ....150..141F (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Positional data ; Proper motions
Keywords: astrometry - binaries: general - catalogs - proper motions
Abstract:
Proper motions are computed and collected in a catalog using the
Hipparcos positions (epoch 1991.25) and URAT1 positions (epoch 2012.3
to 2014.6). The goal is to obtain a significant improvement on the
proper motion accuracy of single stars in the northern hemisphere, and
to identify new astrometric binaries perturbed by orbital motion. For
binaries and multiple systems, the longer baseline of Tycho2 (∼100yr)
makes it more reliable despite its larger formal uncertainties. The
resulting proper motions obtained for 67340 stars have a consequent
gain in accuracy by a factor of ∼3 compared to Hipparcos. Comparison
between UrHip and Hipparcos shows that they are reasonably close, but
also reveals stars with large discrepant proper motions, a fraction of
which are potential binary candidates.
Description:
Proper motions of 67340 Hipparcos stars with declination >-15°,
depending on the URAT1 coverage. Proper motion uncertainties are
around 0.35mas/yr. Stars being either known or suspected binaries in
the Hipparcos catalog, or recognized astrometric binaries in the
Makarov & Kaplan (2005, Cat. J/AJ/129/2420) catalog have been flagged.
5054 stars with discrepant proper motions with Hipparcos on a
3.5σ basis are also flagged. See the published paper for a
description of the accurate propagation of position errors for this
catalog.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
urhip.dat 90 67340 UrHip catalog
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See also:
I/246 : The ACT Reference Catalog (Urban+ 1997)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/329 : URAT1 Catalogue (Zacharias+ 2015)
J/AJ/129/2420 : Proper motion derivatives of binaries (Makarov+, 2005)
Byte-by-byte Description of file: urhip.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP Hipparcos identification number
8- 17 I10 --- TYC2 ? Tycho-2 identification number (1)
19- 30 F12.8 deg RAdeg Right Ascension, ICRS, at URAT1 epoch Epoch (2)
32- 43 F12.8 deg DEdeg Declination, ICRS, at URAT1 epoch Epoch (2)
45- 47 I3 mas e_pos Uncertainty in RA*cos(DE) and DE (2)
49- 56 F8.3 yr Epoch URAT1 epoch of the position RA,DE
58- 66 F9.3 mas/yr pmRA Proper motion in RA*cos(DE) (mas/yr)
68- 76 F9.3 mas/yr pmDE Proper motion in DE (mas/yr)
78- 82 F5.3 mas/yr e_pmRA Uncertainty in pmRA (mas/yr)
84- 88 F5.3 mas/yr e_pmDE Uncertainty in pmDE (mas/yr)
90 A1 --- Flag [AUCGOVX] Binarity flag (3)
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Note (1): The Tycho-2 number is a concatenation from Tycho-2's TYC1 (4 bytes),
TYC2 (5 bytes) and TYC3 (1 byte). Zeros are replacing blank spaces, so the
length of tyc2 is always 4+5+1 = 10 bytes.
Note (2): RA,DE and their uncertainties are taken from the URAT1 catalog.
Note (3): Binarity flag as follows:
A = Recognized astrometric binaries from the Makarov & Kaplan list
(2005, Cat. J/AJ/129/2420). Supersedes any additional Hipparcos
C,G,O,V,X flag.
U = Not a known or suspected binary star, but with discrepant proper motions
between UrHip and Hipparcos on a 3.5 sigma basis.
C = solutions for the components (Hipparcos binary flag)
G = acceleration or higher order terms (Hipparcos binary flag)
O = orbital solutions (Hipparcos binary flag)
V = variability-induced movers (apparent motion arises from variability)
(Hipparcos binary flag)
X = stochastic solution (probably astrometric binaries with short period)
(Hipparcos binary flag)
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Acknowledgements:
Julien Frouard, jfrouard(at)federatedit.com
(End) Julien Frouard [USNO], Patricia Vannier [CDS] 19-Oct-2015