I/302 XC1 catalogue of positions and proper motions (Fedorov+, 2005)
The CX1 catalogue of positions and proper motions of faint stars around
the ICRF sources.
Fedorov P., Myznikov A.
<Kinematics and physics of celestial bodies, Supplement, 5, (2005)>
ADC_Keywords: Positional data ; Proper motions ; Magnitudes, photographic
Keywords: astrometry - reference systems - catalogues
Description:
We present the astrometric catalogue of faint reference stars in
255deg2 sized fields with ICRF objects of northern hemisphere. The
XC1 is based on our results of measurements and astrometric reduction
of digitized images of Schmidt plates POSS-I and POSS-II sky surveys
obtained from USNOFS PMM Image Archive. The Tycho-2 (Cat. I/259)
catalogue was used as a reference catalogue for astrometric
reductions. The mean positions and proper motions of stars were
derived from their individual positions at the different epochs. For
some stars the 2MASS (Cat. II/246) positions were used also. The
limiting magnitude is about V=19mag. The estimated external errors are
50-150mas in positions at mean epoch, and 2-5mas/yr in proper motions,
depending on magnitude. The catalog is present as a set of individual
fields in separate files. The name of each file is the ERS designation
of corresponding ICRF radio source.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
xcfields.dat 106 856421 The XC1 catalogue
xcindex.dat 21 255 Index to the XC1 fields
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See also:
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/284 : The USNO-B1.0 Catalog (Monet+ 2003)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: xcfields.dat
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Bytes Format Units Label Explanations
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1- 13 F13.9 deg RAdeg Right Ascension, ICRS, Ep=J2000 (1)
15- 27 F13.9 deg DEdeg Declination, ICRS, Ep=J2000 (1)
29- 32 F4.1 mag Omag Magnitude from O-plate (2)
34- 37 F4.1 mag Emag Magnitude from E-plate (2)
39- 42 F4.1 mag Jmag Magnitude from J-plate (2)
44- 47 F4.1 mag Fmag Magnitude from F-plate (2)
49- 52 F4.1 mag Nmag Magnitude from N-plate (2)
54- 61 F8.3 mas/yr pmRA proper motion on RA*cos(DE)
63- 70 F8.3 mas/yr pmDE proper motion on DE
72- 74 I3 mas e_RAdeg Internal error in RA at mean epoch (3)
76- 78 I3 mas e_DEdeg Internal error in DE at mean epoch (3)
80- 83 F4.1 mas/yr e_pmRA Internal error in pmRA*cos(DE) (3)
85- 88 F4.1 mas/yr e_pmDE Internal error in pmDE (3)
90- 97 F8.3 yr Epoch Mean epoch of observations
99-100 I2 --- Npos Number of individual star positions used to
derive mean position and proper motion (4)
102-106 F5.2 yr deltaT Maximal epoch difference
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Note (1): J2000 epoch position were derived from mean positions at mean epoch
using XC1 proper motion.
Note (2): All XC1 magnitudes are rough and can be used for identification
purposes only.
Note (3): Internal errors are derived from the scatter of the individual
positions of a star which form the mean position at mean epoch and
proper motion.
Note (4): To derive mean positions and proper motions minimum 5 individual
positions from O, E, J, F and N plates were used. Additionally,
the 2MASS positions for successfully identified stars were used also.
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Byte-by-byte Description of file: xcindex.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Field Field name (based on position of corresponding
ICRF source)
10- 15 I6 --- RecNo The record number for the first star in each
XC1 field
17- 21 I5 --- Nstar The number of stars in the XC1 field
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Acknowledgements: A. Myznikov, Myznikov(at)astron.kharkov.ua
(End) Patricia Vannier [CDS] 26-Jan-2006