wsa logo
WSA Home
Start Here
Data Overview
Known Issues
the Surveys
* Coverage Maps
Schema browser
Data access
Archive Listing
Menu query
Freeform SQL
Analysis services
SQL Cookbook
Release History
wsa logo bottom
Home | Overview | Browser | Access | Login | Cookbook | nonSurvey 
  WSA logo

DR6 Release - October 13th 2009 (GPS added Jan 8th 2010)

Important note:

DR6 does not currently contain UDS detection/source data.

Please see UKIDSSDR5PLUS for UDS data. The charts linked below show the status of the UKIDSS surveys in this release. This 6th release, like the DR5plus release, only contains one database, UKIDSSDR6plus, which contains all the data, i.e. includes data from fields that have incomplete waveband coverage as prescribed by a given survey. The WSA DR6plus release contains views of the survey source tables that allow users to easily target their queries at only those areas that have complete waveband coverage. The names of the source table views are lasYJHKsource, gpsJHKsource, gcsZYJHKsource and dxsJKsource. These names reflect the required waveband coverage. They appear in the schema browser under both the table and view sections. The UDS being only one field that now has coverage in J, H and K does not require a view.

A description of the data and how it is held in the archive is given in the data overview.

DR6 Release Summary

Survey No. of multiframes No. of objects in
detection table
No. of sources in
source table
Approximate depths Plots
LAS 391,218 112,060,881 50,31,208 Y=20.2, J=19.6, H=18.8, K=18.2 link
GPS 251,374 1235445188 604327143 J=19.8, H=19.0, K=18.1 link
GCS 109,140 77,084,422 41,411,783 Z=20.4, Y=20.1, J=19.6, H=18.8, K=18.2 link
DXS 213,716 12,810,888 1,223,362 J=20.9-22.4,K=19.2-21.2 link
UDS 110,456 0 currently 0 currently  K=22.3 link

New in DR6:

  • The deblending error for extended source photometry described in known issues has now been fixed.
  • The LAS now has second-epoch observations in the J filter in some fields. The detections from both epochs are merged into the lasSource table using attributes J_1 and J_2.
  • The DXS has some new attributes in the dxsVariability table: jMinMag, jMaxMag, jNGt3sig, etc, which give the minimum and maximum magnitude of the individual observations of a source and the number of observations that are more than 3 standard deviations from the mean. These are calculated for each filter. In the dxsVarFrameSetInfo table, the attributes aStrat, bStrat and cStrat which gave the parameters for the best fit to the photometric noise as a function of magnitude have been replaced by aStratPht, bStratPht and cStratPht and the equivalent attributes for the astrometric noise (aStratAst, bStratAst, cStratAst) have been added. However, the astrometric fit has not yet been calculated, so the astrometric noise attributes are set to defaults.
  • The DXS deep stacks have been processed with the correct smoothing function at the time of extraction, resulting in fewer false detections at the faint end.
  • Data from intermediate stacks with one or more deprecated extensions are now used in the stacking. These extensions are given a weighting of 0 during stacking. The totalExpTime attribute in MultiframeDetector is calculated on an extension by extension basis and takes into account missing exposure from these frames.
  • If there is only one observation of a DXS field in a particular pointing and band, then a deep stack is no longer created, and the intermediate stack is used in the dxsMergeLog table instead. We have added the productID and releaseNum attributes to ProgrammeFrame to track which deep or intermediate stacks correspond to which product in RequiredStack.
Particular attention should be given to any notes detailing limitations and known issues - see below, known issues and data overview.

Home | Overview | Browser | Access | Login | Cookbook | nonSurvey
Listing | Region | MenuQuery | FreeSQL
Links | Credits

WFAU, Institute for Astronomy,
Royal Observatory, Blackford Hill
Edinburgh, EH9 3HJ, UK