HOW-TO Create global astrometric SourceLists

To derive a global astrometric solution, special SourceLists need to be made. For this purpose GAstromSourceListTask objects are used. The global astrometric solution can be derived using the GAstromTask (see HOW-TO Create a global astrometric solution).

GAstromSourceListTask Example

The GAstromSourceLists required for the GAstromTask are made with the GAstromSourceListTask. Using the DPU this can be done for example like this:

awe> dpu.run('GAstromSL', i='WFI', o='M31_?', d='2000-04-28', c='ccd50', f='#842', C=0)

or

awe> dpu.run('GAstromSL', red=['Sci-#842-ccd50-Red.fits'], C=0)

When running locally the equivalent commands are:

awe> task = GAstromSourceListTask(instrument='WFI', object='M31_?',
                                  date='2000-04-28',
                                  chip='ccd50', filter='#842', commit=0)
awe> task.execute()

or

awe> task = GAstromSourceListTask(red_filenames=['Sci-#842-ccd50-Red.fits'],
                                  commit=0)
awe> task.execute()

where ‘instrument’ is the instrument name (mandatory argument), ‘object’ is the object name or wildcard pattern, ‘date’ is the date of the observations, ‘chip’ is the CCD name, ‘filter’ is the filter name, ‘red_filenames’ is a list of filenames of ReducedScienceFrames, and ‘commit’ is the commit switch used to commit the results to the database. In the first example, a sourcelist is created from a CoaddedRegriddedFrame, while in the second example the same is done from a single ReducedScienceFrame.