Bgdlocal91.qcl prompts for the names of two input files, a source CUBE (or TIME series) and a off-source CUBE (or TIME series). Both of these files should have been cleaned previously. The off-source CUBE is used to derive a background model described by six coefficient files:

1. bgd_constant001.phad
2. bgd_sud.phad
3. bgd_cor.phad
4. bgd_saa_1.phad

Bgdlocal91.qcl also prompts for the names of at least two output files, one to contain the model background corresponding to the period covered by the source observation and the other to contain the background subtracted source observation.

Optionally bgdlocal91.qcl can subtract a model background from the off-source observation. Inspection of the "incestuously" subtracted off-source CUBE will give a guide to the quality of the background model derived from the off-source observation, and suggest periods of the background observation which should be omitted. If this option is selected bgdlocal91.qcl will prompt for the names of two more output files, one containing the model background corresponding to the period covered by the off-source observation and the other containing the background subtracted off-source observation.

Bgdlocal91.qcl requires up to seven input parameters. The QX parameter system is used to read these parameters.

1. The name of the input source CUBE (or TIME series).
2. The name of the input off-source CUBE (or TIME series).
3. The name of the CUBE (or TIME series) containing the background model corresponding to the period covered by the source observation.
4. The name of the background subtracted source observation.
5. Controls whether a model background is subtracted from the off-source observation. The default is Yes, in which case background subtraction is performed.
6. The name of the CUBE (or TIME series) containing the background model corresponding to the period covered by the off-source observation.
7. The name of the background subtracted off-source observation.