The catalogue ASCC-2.5 is available at
http://cdsarc.u-strasbg.fr/viz-bin/Cat?I/280A
ftp://cdsarc.u-strasbg.fr/pub/cats/I/280A
Description: The All-Sky Compiled Catalogue of 2501304 stars (ASCC-2.5) with the limiting magnitude V=12-14 is a result of a merging of star lists from present day large high-precision catalogues from space ( Hipparcos- Tycho family catalogues: Hipparcos main catalogue including Multiple System Annex (I/239), Tycho-1 (I/239), Tycho-2 (I/259), ACT-RC (I/246), TRC(I/250)) and ground-based (PPM-N (I/146), PPM-S (I/193), PPM-add (I/208), CMC11 (I/256)) observations and reduction to standard systems of corresponding stellar data. Main stellar data presented in the ASCC-2.5 are the equatorial coordinates (J2000, epoch 1991.25), proper motions in the Hipparcos system, B and/or V stellar magnitudes in the Johnson system. Additionally for some stars are given trigonometric parallaxes, spectral classes in the MK or HD system, multiplicity and variability flags, Hipparcos, Tycho-2, HD, DM designations. Equatorial coordinates and their standard errors were taken from the source catalogues in accordance with the priority: Hipparcos (I/239/hip_main), Tycho-2 (I/259), Tycho-1 (I/239/tyc_main), CMC11 (I/256), PPM (I/146, I/193, I/208). Proper motions from the source catalogues were compared with Hipparcos data. The compiled proper motions in the Hipparcos system and their standard errors were computed as the weighted means. The weights were set in accordance with the proper motion errors listed for individual stars in the source catalogues. Trigonometric parallaxes are taken from Hipparcos and Tycho-1 catalogues. Stellar B, V magnitudes were determined on the basis of the ground-based photometric data taken from CMC11, Hipparcos, and space B_T_, V_T_ from Tycho-1, Tycho-2. Magnitudes from PPM catalogue were used if no other photometric data were available. Tycho data were transformed to the Johnson system with: V = V_T_ - 0.09 (B-V)_T_ + d_V_, (B-V) = 0.850 (B-V)_T_ + d_(B-V)_, i.e. using recommendations from the Introduction to the Tycho catalogue and including additional corrections d_V_ and d_(B-V)_. These additional corrections were determined by comparison with ground-based data in the Johnson system. These corrections depend non-linearly on colour and reach 0.02 and 0.04 mag, respectively. Spectral classes in MK or HD systems were taken from Hipparcos, CMC11, and PPM catalogues. Multiplicity and variability flags were taken from Tycho-1, Tycho-2, Hipparcos, CMC11, and PPM catalogues. The 1st version of the ASCC-2.5 contained some errors in the zones -1 to +1 degree which have been corrected (see details in the "History" section below); 2 files (ccp00.dat and ccm00.dat) have consequently been modified, and a new file (ccadd.dat) contains the previously missing stars (including components of multiple systems). Notice that the ASCC numbers did not change between the two versions, but additional numbers (2600001 to 2603318) were assigned. Stars in the ASCC-2.5 are divided into 31 files: 30 files are ordered by declination (North and South polar caps and 28 bands with a width of 5 degrees), then sorted in right ascension order within each file; the 31st file "ccadd.dat" contains additional stars that were not present in the 1st version.
File Summary:
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FileName Lrecl Records Explanations
ReadM 80 . This file
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ccp70.dat 169 66363 Declination from +70.0 to +90.0
ccp65.dat 169 33983 Declination from +65.0 to +69.99999999
ccp60.dat 169 53771 Declination from +60.0 to +64.99999999
ccp55.dat 169 71394 Declination from +55.0 to +59.99999999
ccp50.dat 169 70957 Declination from +50.0 to +54.99999999
ccp45.dat 169 75767 Declination from +45.0 to +49.99999999
ccp40.dat 169 80743 Declination from +40.0 to +44.99999999
ccp35.dat 169 95077 Declination from +35.0 to +39.99999999
ccp30.dat 169 99016 Declination from +30.0 to +34.99999999
ccp25.dat 169 92121 Declination from +25.0 to +29.99999999
ccp20.dat 169 89789 Declination from +20.0 to +24.99999999
ccp15.dat 169 83858 Declination from +15.0 to +19.99999999
ccp10.dat 169 87180 Declination from +10.0 to +14.99999999
ccp05.dat 169 92853 Declination from +05.0 to +09.99999999
ccp00.dat 169 88230 *Declination from +00.0 to +04.99999999
ccm00.dat 169 78912 *Declination from -00.0 to -04.99999999
ccm05.dat 169 80109 Declination from -05.0 to -09.99999999
ccm10.dat 169 84142 Declination from -10.0 to -14.99999999
ccm15.dat 169 92036 Declination from -15.0 to -19.99999999
ccm20.dat 169 96430 Declination from -20.0 to -24.99999999
ccm25.dat 169 97134 Declination from -25.0 to -29.99999999
ccm30.dat 169 97264 Declination from -30.0 to -34.99999999
ccm35.dat 169 94151 Declination from -35.0 to -39.99999999
ccm40.dat 169 97810 Declination from -40.0 to -44.99999999
ccm45.dat 169 98216 Declination from -45.0 to -49.99999999
ccm50.dat 169 95662 Declination from -50.0 to -54.99999999
ccm55.dat 169 94846 Declination from -55.0 to -59.99999999
ccm60.dat 169 80669 Declination from -60.0 to -64.99999999
ccm65.dat 169 57295 Declination from -65.0 to -69.99999999
ccm70.dat 169 72217 Declination from -70.0 to -90.0
ccadd.dat 169 3318 *Additional stars
fals.dat 333982 *False stars removed from 1st version
corr.dat 333948 *List of stars corrected from 1st to 2nd version
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Note on ccp00.dat, ccm00.dat, cadd.dat, fals.dat, corr.dat: files added or modified in 2nd version
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/246 : The ACT Reference Catalog (Urban+ 1997)
I/250 : The Tycho Reference Catalogue (Hog+ 1998)
I/146 : Positions and Proper Motions - North (Roeser+, 1988)
I/193 : Positions and Proper Motions - South (Bastian+ 1993)
I/208 : The 90000 stars Supplement to the PPM Catalogue (Roeser+, 1994)
I/256 : Carlsberg Meridian Catalogs (CMC, 1999)
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Author's Address: Nina V. Kharchenko Main Astronomical Observatory NAS of Ukraine
27 Academica Zabolotnogo Str.
03680 Kiev Ukraine
Voice: +(380)44-266-4768 Fax: +(380)44-266-2147 e-mail: nkhar@mao.kiev.ua