[daip] IMAGR without beam maps

[Eric Greisen]

Steven Spangler wrote:
> Hi Eric,
> I am running IMAGR and calculating only the dirty maps; no cleaning. The 
> question I have is that if I am only calculating the dirty maps, how do 
> I tell IMAGR to not compute the dirty beam?  My motivation in doing so 
> is that I don't want to fill up the disk with hundreds of beam maps.
> 
> The documentation indicates that specifying "allokay=1" will do it, but 
> my experience is that it has as much effect as an ordinary bullet on a 
> vampire.
> 
> I should probably explain what I am up to so you don't think that my 
> senility has finally become completely obvious and I am reverting to 
> interferometry, 1976-style.
> 
> I image sources through the solar corona, and would like to do fast 
> cadence to see if I can see coronal disturbances propagating across 
> double radio sources.  I have a beautiful data set from August 2003, and 
> I am seeing if I can do anything from maps with 30 second records. 
> These  maps are pretty crummy (they look about the ones in your summer 
> student interferometry lecture from 1976), and my thinking is that CLEAN 
> isn't necessary since I am only measuring the two brightest components 
> in the source.  I am not sure this is correct, but I would like to do 
> enough analysis of this sort to know what the story is.
> 
> Suppressing beam calculations would save me some time in housekeeping.
> 
> I expect to be at the AOC in mid August.  If you will be in Socorro at 
> that time, I would enjoy talking with you about this.

The beam image is used to provide a correct scaling factor for the data 
image and so is essential.  The allokay option is for restarting a clean 
  and states that the beams and perhaps even the residual images are all 
set already.  It checks that the beam is present and will not let you 
fool it.  A script that includes a zap will be needed.

Eric