Peter Weilbacher Sort input pixel tables into lists of files per exposure, merge pixel
tables from all IFUs of each exposure.
Correct each exposure for differential atmospheric refraction (unless
--lambdaref is far outside the MUSE wavelength range).
Then the flux calibration is carried out, if a response curve was given
in the input; it includes a correction of telluric absorption, if a
telluric absorption correction file was given.
Then the sky subtraction is carried out (unless --skymethod="none"),
either directly subtracting an input sky continuum and an input sky
emission lines (for --skymethod="subtract-model"), or
(--skymethod="model") create a sky spectrum from the darkest fraction
(--skymodel_fraction, after ignoring the lowest --skymodel_ignore as
artifacts) of the field of view, then fitting and subtracting
sky emission lines using an initial estimate of the input sky lines;
then the continuum (residuals after subtracting the sky lines from the
sky spectrum) is subtracted as well. If --save contains "skymodel", all
sky-related products are saved for each exposure.
Afterwards the data is corrected for the radial velocity of the
observer (--rvcorr), before the input (or a default) astrometric
solution is applied.
Now each individual exposure is fully reduced; the pixel tables at this
stage can be saved by setting "individual" in --save.
If multiple exposures were given, they are then combined. If --save
contains "combined", this final merged pixel table is saved.
Finally (if --save contains "cube"), the data is resampled into a
datacube, using all parameters given to the recipe. The extent and
orientation of the cube is normally computed from the data itself, but
this can be overridden by passing a file with the output world
coordinate system (OUTPUT_WCS), for example a MUSE cube. This can also
be used to sample the wavelength axis logarithmically (in that file set
"CTYPE3='AWAV-LOG'").
As a last step, the computed cube is integrated over all filter
functions given (--filter) that are also present in the input filter
list table.