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Compute primary beam, apply it to images or correct single-field CLEAN image for flat-field.
By default, with no option or only the /TRUNCATE option, correct the (single-field) CLEAN image from the (approximate) primary beam attenuation, in order to create the sky brightness image (named SKY). The truncation level is given by default by variable MOSAIC_TRUNCATE, and can be overriden by the /TRUNCATE option.
The primary beam model depends on the Telescope used in the data. If BeamSize (in radian) is specified, it is a Gaussian with the corresponding half-power beam size. If not, the parameters are taken from the telescope parameters, as found in the telescope section of the CLEAN image and the observing frequency from the CLEAN image. For ALMA, the model is the Fourier transform of a uniform 10.4 m diameter disc with 0.7 m central blockage. For NOEMA and all other telescopes, it is a simple Gaussian with appropriate size.
The SKY image is written with extension .lmv-sky by command WRITE.
Options /APPLY, /COMPUTE or /CORRECT modify the default behaviour. These 3 options are mutually exclusive.