This is a README file for the ftp directory bulge_dia_variables,
the catalog of candidate variables from the Difference Image Analysis
of the OGLE-II Galactic Bulge data.

This catalog may be accessed online at:
http://bulge.princeton.edu/~ogle/ogle2/bulge_dia_variables ,
with short description and a postscript paper with full details.

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NEW!

Older three-season ogle2 data files were moved to subdirectories
SEASONS_1997_to_1999. There are also new subdirectories SEASONS_1997_to_2000
with *the same variables* detected using difference frames from 1997-1999
and extended light curves covering also the last (fourth) ogle2 season of 2000.
In particular the DIA centroid is the same as before and does not use new
information from frames taken in 2000. Reference images are also the same.

The fourth season makes insignificant difference for detecting continuous
variability, but the present sample misses transient objects from 2000.

Extended files have a "4" in their names.

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bulge_dia_variables contains:

catalog_description.txt - detailed explanation of columns in provided files
fits_tables - directory with *_cat.fts and *_db.fts files,
              catalog (1 entry per object) and
              light curve database (all measurements for all objects)

plain_text  - directory with BUL_SC* subdirectories (text version of
              light curves, 1 file per object), BUL_SC*.tar - whole
              directories packed for easy tranfer,
              and *_cat.dat files - text version of catalog files


reference_frames - directory with reference FITS images (2k x 8k)
                   converted to 2 byte INTEGERS and compressed,
                   and BUL_SC* subdirectories with 256 subframes
                   of the reference image for each field, also
                   as 2 byte INTEGERS and compressed. Numbering of
                   subframes is reflected in the file name
                   ref_x_y_u.fts.gz, where x is between 1 and 3,
                   and y is between 1 and 64