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The Field 287 dataset

The ESO/SRC field 287 database contains a specialised data set produced by the SuperCOSMOS measuring machine. It consists of scans of around 200 Schmidt plate exposures taken in the single standard southern survey field ESO/SRC 287, RA 21h28; Dec -45 (B1950.0) over a period of 25 years from around 1977 to 2002. Passband coverage consists of 14 U band, 81 B band, 82 R band and 29 I band plates along with four stacks of a small subset of the best 8 plates from each passband. Included in the set are the UKST B, R and I survey plates that are part of the full SSA. The field coverage is approximately 6x6 square degrees.

The field 287 data set has been internally calibrated for the best possible relative photometry, and offers time-resolved measurements over the 25 year period to B~22 and R~21; coverage in U and I is limited to the more recent ~10 year part of that period, and reaches U~20 and I~18. Typical photometric accuracy is around 0.05mag RMS at intermediate magnitudes, rising to 0.30 mag at the respective plate limits. Hence, the field 287 database is a great resource for exploring photometric variability in a wide variety of Galactic and extra-Galactic objects.

The arrangement of the data follows the normalised SSA design with a Source and Detection table. Detection contains the standard IAM catalogues from the individual epoch plates and stacks in all passbands; Source contains the merged multi-colour source list generated from the four stacks (the source merging process was identical to the source merging procedure in the SSA). Also contained in the database are a Plate table which holds details of the set of plates scanned; a table of known quasi-stellar objects (KnownQSO); a neighbour table on Source (SourceNeighbours); and a set of cross-neighbour tables that match objects in Source with detection (SourceXDetection) and with the known QSO table (SourceXKnownQSO). A complete description of the database schema, including all database objects (tables/rows/columns, functions, indexes and views) is available via the SSA browser - follow the link and expand F287 in the tree-view on the left-hand side.

There are two access modes for the data. For casual browsing, familiarisation with the data and for convenient light-curve generating tools, we recommend the use of a specially-written stand-alone client-side Graphical User Interface that can be launched from here (N.B.: requires Java 1.6; further details of the F287 GUI tool are available here). Users more familar with SQL, and/or the SSA, and the concept of neighbour tables may wish to dive straight into the free-form SQL access - simply prefix all database object names with the string "F287.." - e.g. SELECT TOP 10 * FROM F287..Plate - in order to query the field 287 database as opposed to the SSA.

For more information concerning the dataset and how to explore it, please see the final Section of the SQL Cookbook.