I/197A      Tycho Input Catalogue, Revised version  (Egret+ 1992)
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The Tycho Input Catalogue. Cross-matching the Guide Star Catalog with
the Hipparcos INCA Data Base
     Egret D., Didelon P., McLean B.J., Russell J.L., Turon C.
    <Astron. Astrophys. 258, 217, (1992)>
    =1992A&A...258..217E
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ADC_Keywords: Positional data ; Photometry
Mission_Name: Hipparcos

Description:
    A Tycho Input Catalogue of three million stars brighter than V=12.1
    has been prepared, for the needs of the Tycho mission (Hipparcos
    satellite). This catalogue results from the cross-matching of a subset
    of the Hubble Space Telescope Guide Star Catalog with the Hipparcos
    INCA database. References to these major catalogues, and details about
    the cross-matching procedures are to be found in the paper published
    in Astron. Astrophys. 258, 217-222 (May 1992).

    Among the 3,154,204 stars of the Tycho Input Catalogue, only a bit
    more than 1 million will appear in the final Tycho catalogue. A
    preliminary selection was done in the Recognition process, that was
    based on the first year of the satellite scientific mission (Halbwachs
    et al., =1994A&A...281L..25H). 1,049,971 stars were thus selected,
    and are flagged in this version of the Tycho Input Catalogue.

    The main file contains 3 154 204 records of 80 characters (total size:
    256 Mbytes). It is split into four files tic1 to tic4 for easier
    manipulations.

    An annex file contains the following additional data for a subset of
    the stars:
    (a) the cross-identification with the Hipparcos Input Catalogue
        (117 778 records, flag 26)
    (b) the cross-matching with the INCA database (217 625 records, 
        flag 20). The annex file contains 217 625 records 
        (64 char., 14 Mbytes).

File Summary:
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 FileName  Lrecl   Records    Explanations
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ReadMe        80         .    This file
tic1.dat      80    783952    The catalogue, zones 0/37.5deg
tic2.dat      80    574674    The catalogue, Zones 37.5/90deg
tic3.dat      80    919217    The catalogue, Zones 0/-37.5deg
tic4.dat      80    876361    The catalogue, Zones -37.5/-90deg
tica.dat      64    217625    Annex file, Cross-identifications
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Byte-per-byte Description of file: tic[1-4].dat
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   Bytes Format  Units   Label    Explanations
--------------------------------------------------------------------------------
   1-  4  I4     ---     TICID1   GSC region number
   6- 10  I5     ---     TICID2   GSC running number in region
  11- 20  I10    10mas   RAcs     [0/129600000] Right ascension J2000.0
                                    Epoch 1990, in 0.01arcsec
  21- 29  I9     10mas   SPDcs    [0/64800000] South Polar Distance (=Dec+90)
                                    Epoch 1990, in 0.01arcsec
  31- 34  I4     10mas   ePos     ?=0 Error on position  in 0.01arcsec
  36- 38  I3     cmag  e_Bmag     ?=0 Error on B mag. in 0.01 mag.  (0=unknown)
  39- 43  I5     cmag    Bmag     ?=0 B magnitude in 0.01 mag.  (0=unknown)
  45- 47  I3     cmag  e_Vmag     ?=0 Error on V mag. in 0.01 mag.  (0=unknown)
  48- 52  I5     cmag    Vmag     V magnitude in 0.01 mag.  (0=unknown)
      54  I1     ---     Flag1    FK5 star
      55  I1     ---     Flag2    IRS star
      56  I1     ---     Flag3    Photometric standard for Tycho
      57  I1     ---     Flag4    Monitor star : random set
      58  I1     ---     Flag5    Monitor star : selected from TIC flags
      59  I1     ---     Flag6    Monitor star : NGC, ADS system
      60  I1     ---     Flag7    Photometric star
      61  I1     ---     Flag8    Monitor star (logical OR of #1 to #6)
      62  I1     ---     Flag9    GSC/INCA discrepancy
      63  I1     ---     Flag10   Star selected in the Recognition process
      64  I1     ---     Flag11   GSC/INCA magnitude discrepancy
      65  I1     ---     Flag12   INCA (or CDA) entry NOT in  GSC 1.0
      66  I1     ---     Flag13   Source of position (0: GSC; 1: INCA)
      67  I1     ---     Flag14   -id.- for B magnitude
      68  I1     ---     Flag15   -id.- for V magnitude
      69  I1     ---     Flag16   Non-stellar GSC image ("unknown" class)
      70  I1     ---     Flag17   Component of TIC pair (sep. < 20")
      71  I1     ---     Flag18   Close pair with one single entry (sep < 3")
      72  I1     ---     Flag19   Component of INCA pair (sep < 10")
      73  I1     ---     Flag20   INCA/CDA star (cross-id. in Annex file)
      74  I1     ---     Flag21   Known proper-motion
      75  I1     ---     Flag22   Known high proper-motion (>0.15"/yr)
      76  I1     ---     Flag23   Known parallax
      77  I1     ---     Flag24   Known variable
      78  I1     ---     Flag25   Known multiple system
      79  I1     ---     Flag26   Hipparcos Input Catalogue star (Annex file)
      80  I1     ---     Flag27   CDA star (complementary astrometric data)
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Byte-per-byte Description of file: tica.dat
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   Bytes Format  Units   Label    Explanations
--------------------------------------------------------------------------------
   1-  5  I5     ---     TICID1   GSC region number
   6- 10  I5     ---     TICID2   GSC running number in region
  11- 22  A12    ---     NCSI     CSI number (from SIMBAD and the INCA database)
  23- 26  A4     ---     Comp     Component code (A, B, AB, etc.) or blank
  27- 46  A20    ---     ID       Star Identification (from HD, DM, or
                                    other catalogues)
  47- 51  F5.2   mag     Dmag     ?Mag(GSC) - Mag(INCA)
  54- 58  F5.2   arcsec  Dpos     ?Distance pos(GSC)-pos(INCA) in arcsec.
  59- 64  I6     ---     HIC      ?HIPPARCOS Input Catalogue number
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Notes and warnings concerning the present release:

  The following corrections have been applied to the TIC,
  generating some differences with respect to the 'operational'
  version of TIC described in the Astron. & Astrophysics paper :

   o corrected coordinates for high proper motion stars (see
     footnote 2 in the A&A Paper).  These stars are the stars
     with flag 12 (INCA star without GSC counterpart) and flag 22
     (proper motion larger than 0.15"/yr).  2130 objects in TIC have
     both flags set.

     For these stars, the original INCA position (at epoch 1990) have
     been searched for, and the correct positions restored.

   o additional TIC entries have been assigned a consistent GSC
     number provided by the STScI team (rather than a number
     starting at 10001); note that the brighter ones (V< 7.5) appear
     in GSC version 1.1, with plate name +056.

   o in three GSC regions (3588, 5706, and 7899) where the
     numbering sequence restarts to 0 after 10000 in the GSC
     (in the CD-ROM edition of GSC only the last four digits are
     printed), correct numbers have been restored in TIC
     (thus in the range 10000-13000).

   o The HIC numbers in the annex file have been updated (from
     the old IC5 in the 'operational version', to the HIC numbers
     as published in ESA SP-1136).
     Note that there are 23 HIC duplicates (TIC entries having the
     same HIC number : these are A and B components of close systems),
     and that there are 110 entries which have been suppressed from
     the Hipparcos Catalogue after the start of the mission and before
     the publication of the Catalogue (see Table 1 in ESA SP-1136).

   o The annex file contains also 60 INCA duplicates (TIC entries having
     the same INCA identification); this is due to late corrections
     in the INCA file, and the duplicate TIC entry is likely to be
     redundant.


See also:
    I/196 : Hipparcos Input Catalogue, Version 2 (Turon+, 1993)
    I/207 : Preliminary list from Tycho observations (Halbwachs+ 1994)
    I/239 : Hipparcos and Tycho Catalogues

Historical Notes:
  * 10-Jan-1994: Original version of this file: Jean-Louis Halbwachs [CDS]
  * 09-Nov-1994: This file rewritten by N.P.M. Kuin [ADC]
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(End)                                       N.P.M. Kuin [ADC]        09-Nov-1994
