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< Main Astronomical Observatory of the National Academy of Sciences, Kiev, Ukraine, (2001)>
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ADC_Keywords: astrometry; photographic catalogue; proper motions
Description: GPM is the newer version of the General Compiled Catalogue of Absolute Proper Motions, derived with respect to galaxies within the plan called Catalogue of Faint Stars (KSZ, Deutch 1952). The programme was proposed for several observatories of the former Soviet Union, China, Rumania and Spain. There are some resulting individual catalogues of absolute proper motions of stars compiled at five observatories (Kiev, Pulkovo, Moscow, Tashkent and Shanghai). The GPM combines these catalogues and comprises absolute proper motions for 52 805 stars from 8 to 15.5 mag in 185 fields north of -25 degrees of declination. The size of each region is nearly 1.5 square degrees. The mean standard error of proper motion is 8 mas/yr on average. Detailed information on the construction methodology and input data can be found in (Rybka & Yatsenko 1997).
In addition to absolute proper motions the GPM containes accurate equatorial coordinates and three-colour B V R photometry for the vast majority of its stars ( Rybka 2000).
Additional information was selected from all available sources. Usage of the ACT catalog should provide improved positions (mostly in removing of systematic errors) and improved photometry (because the brightest stars in each GPM region had B and V magnitudes measured by the Tycho experiment on the Hipparcos satellite). The mean accuracies achived, as demonstrated by comparison with above catalogue, are 250 mas for the positions and 0.22 mag for B magnitude and 0.26 mag for B-V colour.
The GPM gives right ascensions and declinations for equinox J2000.0 and epoch copied from available sources. They were only presented to identify the GPM stars with those from other catalogues. The compiled catalogue also presents B magnitudes and B-V colours. They were converted to be close to Johnson system. The Tycho stars were also identified in the GPM catalogue. A search area with a radius of 2 arcseconds was used to search for multiple entries of the same star, which may be appeared in the region overlap areas. The detected entries were then removed from the final catalogue. The procedure decreased the number of stars in the catalogue by about 0.4 %.
The adopted catalogue organization includes data in 185 regions sorted according the KSZ region numbers. The data were then sorted nearly in right ascension order within each GPM region. All information needed to associate a point on the sky with region number and provide a more rapid access to that region are given in file region.dat.
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File Summary:
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File Name Lrec Records Explanations
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readme.htm 80 . This file
gpm_cat.dat 73 52 805 The GPM Catalogue
region.dat 36 185 Index to the GPM regions
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See also:
I/220 : The HST Guide Star Catalog (Lasker+ 1992)
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/246 : The ACT Reference Catalog (Urban+ 1997)
I/243 : The PMM USNO-A1.0 Catalogue (Monet 1997)
I/252 : The USNO-A2.0 Catalogue (Monet+ 1998)
Byte-by-byte Description of file: gpm.cat
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Bytes Format Units Label Explanations
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1- 4 I4 --- KSZ *Region number
6-15 F10.6 deg RAdeg Right Ascension J2000.0 at epoch
of original source
16-25 F10.6 deg DEdeg Declination J2000.0 at epoch of
original source
27 I1 --- Flag1 *Discrepancy flag for Positions
29-35 F7.2 yr EP *Epoch of Positions
36-41 F6.1 mas/yr PMRA Absolute Proper Motion in RA *cos(DE)
42-47 F6.1 mas/yr PMDE Absolute Proper Motion in DE
49-52 F4.1 mag B Blue magnitude in Johnson B band
54 I1 --- Flag2 *Discrepancy flag for Photometry
56-60 F5.2 mag B-V *?Johnson B-V colour
62-65 I4 --- Tyc1 *Tycho identifier 1
67-71 I5 --- Tyc2 *Tycho identifier 2
73 I1 --- Tyc3 *Tycho identifier 3
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Note on region number:
Numbers from 1 to 205 are given according to the KSZ plan,
numbers larger than 205 are NGC numbers of the nearest
galaxies from region center.
Note on Flag1 :
blank: typical quality for positions, the standard error = 250 mas
1 : extremely low quality for positions, the standard error may be
larger than 18 arcseconds
Note on EP :
blank: extremely low quality for positions
Note on Flag2 :
blank: typical quality for photometry, the standard error=0.22 mag
1 : low quality for photometry, the standard error=0.35 mag
Note on B-V colour:
B-V = -9.99 if no data
Note on Tyc1, Tyc2, Tyc3:
Tyc1 is the GSC region number, Tyc2 is the running number within the
region, Tyc3 is a component identifier (normally 1)
Byte-by-byte Description of file: region.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- KSZ The KSZ region number
6-10 I5 --- REC The record number for the first star
in each GPM region
12-15 I4 --- N The number of stars in the GPM region
17-26 F10.6 deg RACEN Region center RA (J2000.0)
27-36 F10.6 deg DECEN Region center DE (J2000.0)
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References: