[daip] Advice please

Jim Ulvestad julvesta at aoc.nrao.edu
Fri Aug 18 09:08:49 EDT 2000


Johan van der Walt wrote:
> 
> Attached are the uv plots of two of my program sources. In both cases
> the calibration has been applied. I have the following two questions:
> 
> (1) 18290-0924: How should I interpret the larger fluxes at the
> very small uv distances compared to what seems like noise at larger uv
> distances? To me it seems to be too systematic to be bad data. I get
> the same type of behaviour also for another source.
> 
> (2) 18056-1954: (a) It appears as if this distribution indicates a source.
> Is that correct? (b) The flux density falls rapidly with increasing uv
> distance. Between 0 and 10 there are quite a lot of points that fall
> below what is the general decrease of flux density with increasing uv
> distance. Are these bad points that need to be flagged?
> 
> Thanks
> 
> Johan

I received no attachments ...

(1) This certainly sounds like resolution/halo.  Or possibly a confusing
source.  What is your observing band, what is your configuration, and
is this a snapshot or a lot of data?

(2) Can't make much of a response to this without seeing a plot.

jim ulvestad



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