I/279 Revised Luyten Half-Second Catalogue (Bakos+ 2002)
Revised Coordinates and Proper Motions of the Stars in the
Luyten Half-Second Catalogue
Bakos G.A., Sahu K.C., Nemeth P.
<Astrophys. J. Suppl. Ser. 141, 187 (2002)>
=2002ApJS..141..187B 2002ApJS..141..187B
ADC_Keywords: Positional data ; Proper motions ; Colors
Keywords: astronomical data bases: high proper motion - catalogues
Abstract:
We present refined coordinates and proper motion data for the high
proper motion (HPM) stars in the Luyten Half-Second (LHS) catalogue.
The positional uncertainty in the original Luyten catalogue is
typically >10" and is often >30". We have used the digital scans of
the Palomar Observatory Sky Survey (POSS) I and POSS II plates to
derive more accurate positions and proper motions of the objects. Out
of the 4470 candidates in the LHS catalogue, 4323 objects were
manually re-identified in the POSS I and POSS II scans. A small
fraction of the stars were not found due to the lack of finder charts
and digitized POSS II scans. The uncertainties in the revised
positions are typically ∼2", but can be as high as ∼8" in a few cases,
which is a large improvement over the original data. Cross-correlation
with the Tycho-2 and Hipparcos catalogues yielded 819 candidates (with
mR≲12). For these brighter sources, the position and proper motion
data were replaced with the more accurate Tycho/Hipparcos data. In
total, we have revised proper motion measurements and coordinates for
4040 stars and revised coordinates for 4330 stars. In the printed
version of the paper, we present the updated coordinates and proper
motion information on 528 sources which represent the high proper
motion subset (µ>1"/yr) of the LHS catalogue. The electronic
version contains the updated information on all the 4470 stars in the
LHS catalogue.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 133 4470 Revised Positions and Proper Motions for LHS stars
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See also:
I/87 : LHS Catalogue, 2nd Edition (Luyten 1979)
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/269 : CCDM, Components of Double and Multiple stars (Dommanget+ 2002)
J/AJ/124/1190 : Northern high proper motion stars in DSS (Lepine+, 2002)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- LHS The Luyten Half-Second (LHS, Cat. I/87) number
7- 8 I2 h RAh Hour of Right Ascension (J2000) (1)
10- 11 I2 min RAm Minute of Right Ascension (J2000) (1)
13- 17 F5.2 s RAs Second of Right Ascension (J2000) (1)
19 A1 --- DE- Sign of the Declination (J2000) (1)
20- 21 I2 deg DEd Degree of Declination (J2000) (1)
23- 24 I2 arcmin DEm Arcminute of Declination (J2000) (1)
26- 29 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
31- 36 F6.2 arcsec/yr pm Proper motion
38- 43 F6.2 deg pmPA Position angle of proper motion
45- 49 F5.1 arcsec Dist ? Distance between predicted J2000.0 position
of LHS and our measurements (2)
51- 56 A6 --- Com Comments (3)
58- 59 I2 h RALh Luyten's Hour of Right Ascension (J2000)
61- 62 I2 min RALm Luyten's Minute of Right Ascension (J2000)
64- 65 I2 s RALs Luyten's Second of Right Ascension (J2000)
67 A1 --- DEL- Luyten's Sign of the Declination (J2000)
68- 69 I2 deg DELd Luyten's Degree of Declination (J2000)
71- 72 I2 arcmin DELm Luyten's Arcminute of Declination (J2000)
74- 75 I2 arcsec DELs Luyten's Arcsecond of Declination (J2000)
77- 82 F6.3 arcsec/yr muL Luyten's original proper motion
84- 88 F5.1 deg PAL ? Luyten's original position angle
90- 99 F10.5 yr POSSI ? The POSS I epoch
101-110 F10.5 yr POSSII ? The POSS II epoch
112-115 F4.1 mag Rmag ? The "red" magnitude (4)
117-120 F4.1 mag Bmag ? The "blue" magnitude (4)
122-133 A12 --- ID The Tycho-2 (I/259) or Hipparcos (I/239)
identification (5)
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Note (1): Equatorial coordinates for epoch and equinox 2000.0 using our
astrometry and proper motion measurements. If none of the digital
scans of POSS plates were available, or the difference between the
epochs was not sufficient, proper motions from Luyten were accepted.
If star was not found, both coordinates and proper motions were taken
from Luyten.
Note (2): blank entries indicate coordinates of the LHS Catalogue
were accepted.
Note (3): Comments
1 = DSS I image has poor quality.
2 = DSS II image has poor quality.
B = position shift between the two frames is less than 5", proper motion
data from LHS Catalogue is taken.
H = coordinates, proper motion and magnitudes are from the Tycho-2
Supplement-1 catalogue, i.e. from the Hipparcos catalogue (I/239).
N = star was not found in manual search.
P = POSS II DSS frame was not available.
W = finder chart would have been needed for manual identification, but was
not available.
T = coordinates, proper motion and magnitudes are from the
Tycho-2 catalogue (I/259).
b = for some reason our proper motion measurement is not accurate,
Luyten's data are used.
c = refitting of position was done (due to saturation or merging).
d = double star, or companion of a binary.
m = merging.
i = identification dubious.
s = saturated on at least one of the frames.
Note (4): The red and blue magnitudes are Tycho, Cat. I/239 (Hipparcos),
V and B if star was found in the Tycho-2, Cat. I/259, (Supplement-1)
catalogue, otherwise LHS (I/87) red and photographic magnitudes.
Note (5): Identification of Tycho-2 (I/259) catalogue is of the format
TYC1-TYC2-TYC3, while Hipparcos (I/239) is the single Hipparcos
number followed by the CCDM component identifier (Dommanget & Nys,
1994, See Cat. I/269).
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Acknowledgements:
Kailash C. SAHU, Space Telescope Science Institute, Baltimore, MD
(End) Francois Ochsenbein [CDS] 24-May-2002