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These notes are relevant for Version 6 of the Kepler Input Catalog.


General Comments
Release History
Schema for Latest Release
Schema for CATKEY Database
Schema for SCPKEY Database
Source of Astrometry
Source of KEPMAG for Stars not Observed by the SCP

 

General Comments

  1. The KIC now occupies three databases and not the previous one. The KIC itself uses the KICID field as its primary key, but now includes two new columns (the only new columns since the last version) which are CATKEY and the SCPKEY. CATKEY is the primary key into a relatively small catalog database that includes all bright star cross-references as well as the fluxes from the radio catalogs. Please refer to its schema in the appended document. SCPID is the primary key into another database that will hold SCP data not included in the KIC. At the moment, I just fake this. Should Tim pass along less important data, perhaps just for the calibration stars, these will go into this database. I think that this is the "accepted" way to have extra columns for a relatively few entries in the primary database, and I will be working with Chris to make sure that I get the database end of things correct.

  2. The current version uses SCP data to calibrate the transformations from (O,E,J,F,N) photographic magnitudes to (g,r,i,Kepler) CCD magnitudes. Obviously, this can only be done for those plates which include SCP data, but eventually all plates can be calibrated. For the user, this should be relatively transparent because I used a guess for this transformation in previous versions. However, the content and values in the CQ column have been redefined, and the new version is given in the appended schema. I think that this makes life easier for the user, but I am willing to keep working (The version of 2 days ago was so bad that even Chris complained).

  3. The KIC now includes *ALL* data from the SCP. In the region that covers the nominal pointing, the photographic data have been merged to give a relatively complete view of the sky. In the regions outside the nominal pointing (the SCP standards, I think), only the SCP data are presented. This keeps the KIC size about the same as before, but will satisfy the users that want to examine the SCP standards, etc.

All of this sounds complicated, and it certainly has been non-trivial to make it happen, but the bottom line is pretty simple:

Fire away, but sooner is a lot better than later.
-DaveM

 

Release History

   Version     Approx Date   Comments
   -------------------------------------------------------------------------

      4        01 Apr 2005   Recalibration of photographic magnitudes.

      3        17 Feb 2005   Added colors, fixed bugs, added documentation.
                             Should be version for Team in May 05

      2         1 Feb 2005   Astronomer units instead of integers. Added
                             PARLX, GLONG, GLAT fields.

      1        05 Jan 2005   Fixed SPD/DEC error

      0        27 Dec 2004   Dec 31 2004 release as per Requirements Document

 

Schema for Latest Release

 Column  DB Name      Type      Units        Format, comments, etc.
 -----------------------------------------------------------------------------
   1     RA          double     hours         Right Ascension (HH.HHHHHHH)
   2     DEC         double     degrees       Declination (sDD.DDDDDD)
   3     PMRA        float      arcsec/year   RA proper motion(sMM.MMMM)
   4     PMDEC       float      arcsec/year   Dec proper motion (sMM.MMMM)
   5     UMAG        float      magnitudes    u-band magnitude (MM.MMM)
   6     GMAG        float      magnitudes    g-band magnitude (MM.MMM)
   7     RMAG        float      magnitudes    r-band magnitude (MM.MMM)
   8     IMAG        float      magnitudes    i-band magnitude (MM.MMM)
   9     ZMAG        float      magnitudes    z-band magnitude (MM.MMM)
  10     GREDMAG     float      magnitudes    GRed band magnitude (MM.MMM)
  11     D51MAG      float      magnitudes    D51 band magnitude (MM.MMM)
  12     JMAG        float      magnitudes    2MASS J-band magnitude (MM.MMM)
  13     HMAG        float      magnitudes    2MASS H-band magnitude (MM.MMM)
  14     KMAG        float      magnitudes    2MASS K-band magnitude (MM.MMM)
  15     KEPMAG      float      magnitudes    Kepler-band magnitude (MM.MMM)
  16     KICID       int        (none)        Unique KIC catalog ID
  17     TMID        int        (none)        Unique 2MASS catalog ID
  18     YBID        int        (none)        Unique YB7 catalog ID
  19     ALTID       int        (none)        ID in other catalog (see 20)
  20     ALTSOURCE   int        (none)        Source catalog for ALTID (see 19)
  21     GALAXY      int        (none)        Star/galaxy indicator
  22     BLEND       int        (none)        Isolated/blended indicator
  23     VARIABLE    int        (none)        Constant/variable indicator
  24     TEFF        int        degrees K     Effective temperature (TTTTT)
  25     LOGG        float      cm/sec**2     LOG10 surface gravity (sL.LLL)
  26     FEH         float      solar         LOG10 Fe/H metallicity (sL.LLL)
  27     EBMINUSV    float      magnitudes    E(B-V) reddening (sM.MMM)
  28     AV          float      magnitudes    A_V extinction (M.MMM)
  29     RADIUS      float      solar         Radius (RRR.RRR)
  30     CQ          string     (none)        Source of data - see Notes
  31     PQ          int        (none)        Photometry quality indicator
  32     AQ          int        (none)        Astrophysics quality indicator
  33     CATKEY      int        (none)        Unique integer key to CATALOG DB
  34     SCPKEY      int        (none)        Unique integer key to SCP DB
  35     PARALLAX    float      arcsec        Parallax (sP.PPPP)
  36     GLON        float      degrees       Galactic longitude (DDD.DDDDDD)
  37     GLAT        float      degrees       Galactic latitude (sDD.DDDDDD)
  38     PMTOTAL     float      arcsec/year   Total proper motion (MM.MMMM)
  39     GRCOLOR     float      magnitudes    g-r color (sM.MMM)
  40     JKCOLOR     float      magnitudes    J-K color (sM.MMM)
  41     GKCOLOR     float      magnitudes    g-K color (sM.MMM)
Notes:

The TYPE field shows the suggested minimum precision for storage of the value. The string in the COMMENTS field shows the format of the entry in the ASCII version of the database files. 

  ALTSOURCE values:
        Value         Comments
        ------------------------------------------------------------------
            0        ALTID contains NULL
            1        ALTID contains Hipparcos catalog ID
            2        ALTID contains Tycho2 catalog ID
            3        ALTID contains UCAC2 catalog ID
            4        ALTID contains General Catalog of Variable Stars ID
           11        ALTID contains NED catalog ID
           12        ALTID contains Extended 2MASS Catalog ID
           13        ALTID contains FIRST catalog ID
           14        ALTID contains NVSS catalog ID

  CQ values:
       ASCII character string indicating the source of the calibrated data.

        Value         Meaning
        ------------------------------------------------------------------
        NOCAL         No calibration to optical magnitudes possible.  Used
                      for entries from non-optical catalogs.
        2MASS         Objects found only in 2MASS catalog with no optical
                      counterpart.
        UNCAL         Lack of SCP photometric calibrators on photographic
                      plate prevents calibration.  Values are raw photographic
                      magnitudes in closest band.
        PHOTO         Photographic magnitudes calibrated to Kepler bands.
        SCP           CCD magnitudes from SCP.

PQ values:

Placeholder for SCP values that have yet to be determined. Current version is value between 0-11 which is the count of non-NULL entries in UMAG, GMAG, RMAG, IMAG, ZMAG, GREDMAG, D51MAG, JMAG, HMAG, KMAG, and KEPMAG.

AQ values:

Placeholder for SCP values that have yet to be determined. Current version is value between 0-6 which is the count of non-NULL entries in TEFF, LOGG, FEH, AV, EBMINUSV, RADIUS.

 

Schema for CATKEY Database

 Column  DB Name      Type      Units        Format, comments, etc.
 -----------------------------------------------------------------------------

   1     CATKEY       int       (none)       Unique integer key to CATALOG DB
   2     CATFLAG      int       (none)       Bit flag from catalog merge
   3     TYCHOID      int       (none)       Original ID in Tycho-2 catalog
   4     UCACID       int       (none)       Original ID in UCAC catalog
   5     GCVSID       int       (none)       Original ID in GCVS catalog
   6     SOURCE       character (none)       STAR, XTM, NED, NVSS, FIRST
   7     SOURCEID     int       (none)       ID in original catalog
   8     FLUX1        int       (variable)   First flux in original catalog
   9     FLUX2        int       (variable)   Second flux in original catalog
  10     RAEPOCH      float     year         Epoch of RA coordinate
  11     DECEPOCH     float     year         Epoch of Dec coordinate
  12     JMAG         float     mag          2MASS J magnitude
  13     HMAG         float     mag          2MASS H magnitude
  14     KMAG         float     mag          2MASS K magnitude
Notes:
  1. If the object is a star with one or more cross-identifications in the UCAC, Tycho2, or GCVS catalogs, SOURCE is set to STAR, and all cross-identifications are listed.

  2. If the object comes from a non-optical or other special catalog, SOURCE is set to the name of the catalog (XTM, NED, NVSS, FIRST) and the FLUX1 and FLUX2 are set to the fluxes listed in those catalog.

  3. All entries have non-NULL values for CATKEY, CATFLAG, and SOURCE. For STARS, there will be at least one non-NULL value in TYCHOID, UCACID, and GCVSID. For galaxies and other peculiar objects, there should be non-NULL values in SOURCEID, FLUX1, FLUX2 (depending on catalog), RAEPOCH and DECEPOCH. XTM sources will have non-NULL values in JMAG, HMAG, and KMAG.

 

Schema for SCPKEY Database

 Column  DB Name      Type      Units        Format, comments, etc.
 -----------------------------------------------------------------------------
 
   1     SCPKEY       int       (none)       Unique integer key to SCP DB
   2     RAZONE       int       degrees      Derived from original file name
   3     DECZONE      int       degrees      Derived from original file name
   4     ZONELINE     int       (none)       Line number in original file
Notes:
  1. There is no useful information in this database. Yet. The KIC contains all columns from the SCP database. This is a place holder for future needs.

  2. Illegal values for RAZONE and DECZONE indicate that the original file name did not conform to the naming standards.

 

Source of Astrometry (RA, DEC, PMRA, PMDEC, PARALLAX)

The source of the astrometric quantities depends on which catalog (or catalogs) contain data for this star. To ensure the highest accuracy and to minimize systematic errors, the hierarchy for the choice of astrometric values is as follows

  1. SCP (50 milliarcseconds, but closer to Kepler epoch)

  2. Hipparcos (10 milliarcseconds)

  3. Tycho-2 for V brighter than 8.0 (20 milliarcseconds)

  4. UCAC2 (40 milliarcseconds)

  5. 2MASS (70 milliarcseconds)

  6. USNO-B1.0 (200 milliarcseconds)

The values listed in the KIC come from the first entry in this list that contains each star. The source catalog should be consulted for a detailed discussion of astrometric accuracy. The quantities listed here are global averages.

 

Source of KEPMAG for Stars not Observed by the SCP

Every effort was made to compute a KEPMAG for every star that has enough color information to allow even a poor transformation. The first step is the transformation from the various catalog bands to the SDSS g- and r-bands. These incorporate relatively large errors (at least several tenths of a magnitude), but are (probably) better than nothing. These tests were done, and the first that passed was used.

The second step was to compute KEPMAG as a function of (g,r).

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