addnewkeys

addnewkeys

stsdas.hst_calib.fos

addnewkeys

NAME · USAGE · DESCRIPTION · PARAMETERS · EXAMPLES · NOTES
BUGS · REFERENCES · HELP · SEE_ALSO

NAME

addnewkeys -- Add new keywords to FOS data header files.

The addnewkeys task is a script that adds new header keywords and group parameters to FOS data files. The keywords and group parameters that are added are those that are required by the CALFOS scattered light correction step, as well as new flux calibration steps. CALFOS versions 1.3.1 and later contain a scattered light correction step that was not available in earlier versions. Furthermore, CALFOS versions 2.0 and later contain new flux calibration steps involving corrections for changes in aperture throughput as a function of OTA focus and corrections for changes in instrumental sensitivity over time. It should be noted the new flux calibration is not applicable to spectropolarimetry data.

The scattered light correction requires the "SCT_CORR" calibration switch and the "CCS9" reference table name to be in the raw (.d0h) data file. Furthermore, values of the scattered light (and its estimated error) computed by CALFOS are written to the group parameters "SCT_VAL" and "SCT_ERR". These four header keywords and group parameters do not appear in FOS data files produced before April 1994, and therefore, must be added in order to take advantage of the scattered light correction step when reprocessing old data sets.

The new flux calibration steps require the calibration switches "APR_CORR", "AIS_CORR", and "TIM_CORR". These steps also require the new "CCSA", "CCSB", "CCSC", and "CCSD" reference table names and the "AISHFILE" reference file name. When the new calibration switches are added to existing headers using this task, the old flux calibration switch "FLX_CORR" is set to "OMIT". Since the new flux calibration is not applicable to spectropolarimetry data, only "FLX_CORR" should be set to "PERFORM" for spectropolarimetry observations.

PARAMETERS

images [string]: List of image headers to which the new keywords will be added. Should be .d0h files since it is these files that CALFOS searches for keyword values.

ccs[file name]: Name of the "CCS9" reference table. This name will be used to populate the "CCS9" header keyword when it is added.

ccsa [file name]: Name of the "CCSA" reference table. This name will be used to populate the "CCSA" header keyword when it is added.

ccsb [file name]: Name of the "CCSB" reference table. This name will be used to populate the "CCSB" header keyword when it is added.

ccsc [file name]: Name of the "CCSC" reference table. This name will be used to populate the "CCSC" header keyword when it is added.

ccsd [file name]: Name of the "CCSD" reference table. This name will be used to populate the "CCSD" header keyword when it is added.

ais [file name]: Name of the "AISHFILE" reference file. This name will be used to populate the "AISHFILE" header keyword when it is added.

(scatter = yes) [boolean]: Switch to control whether or not the new keywords and group parameters associated with the scattered light correction are to be added to the header.

(calib = yes) [boolean]: Switch to control whether or not the new keywords associated with the enhanced flux calibration steps are to be added to the header. This is appropriate only for non-polarimetric data.

(verbose = yes) [boolean]: Print operations as they are performed?

EXAMPLES

1. Add all of the new keywords to the image y15i0206t.d0h.

  fo> addnewkeys y15i0206t.d0h

2. Add only the keywords associated with the new flux calibration steps to all raw data (.d0h) files in the current directory.

  fo> addnewkeys *.d0h scatter=no

NOTES

It is the responsibility of the user to insert the appropriate filenames for the CCS9, CCSA, CCSB, CCSC, CCSD, and AIS parameters. The filenames and the actual files are available through the HST Archive using the StarView facility. Once in StarView, the user should utilize the "HST INSTRUMENT/FOS Reference Files" search screen to determine the best calibration files that apply to any specific dataset.