[daip] Re: Problem with the `IMAG' option of UVSUB and CALIB in 31DEC03 AIPS

[Eric Greisen]

Subhashis Roy writes:
 > Hi,
 > 
 > I notice that while using the CMODEL `IMAG' option in UVSUB with
 > FACTOR=-1, the flux density which is added with the CLEAN components is
 > exhorbitently high than expected.
 > 
 > It appears that UVSUB is taking Fourier Transform of flux densities of each
 > pixel, without normalising by the `square of the number of pixels per Beam' 
 > (at least the extra flux density can be expressed closely by the
 > `(number of pixels per Beam)**2').
 > 
 > Same problem exists with CALIB (i.e., with CMODEL `IMAG' and SOLMODE
 > 'A&P', the UV data of the output file has flux densities multiplied by
 > the `(number of pixels per Beam)**2'.

I have put back a change to the modeling routines so that they all
scale the model by
   1) The beam area in the case of Clean image models (with a stern
      warning) 
   2) The total flux / sum of the CC flux in the case of Clean
      component models
It will be available for a MNJ in about 4-5 hours.

Eric Greisen