[daip] Recognition of bad data (

[Jim Ulvestad]

You cannot tell if these data are bad until they are calibrated.
An approximate calibration is applied to the antennas on line, but
it is only approximate, and can easily be off relative to the
other antennas by 10% or 20%.  You must flux-calibrate your data
and then look for inconsistencies in the uv plot.

By the way, if you attach a plot at any time in the future, it
will be much easier for us if you just attach a simple postscript
plot, maybe g'zipped, but without all the uuencoding.  It was
tough for us to get access to your plot.

Hope this helps,

Jim Ulvestad

Johan van der Walt wrote:
> 
> Attached is a uuencode gzipped postscript file of amplitude vs uv distance
> for one of my phase calibrators. No calibration has been applied.
> 
> I would like to know whether it is possible to recognize bad data on
> such a plot. Eg. in the uvrange 35 to 90 there are points with
> amplitudes less than 125 mJy which seems to be separated by a small gap
> from those above it. Also, in the uv range between about 15 and 25
> there is a "spur-like" feature where the amplitudes are greater than
> about 150 mJy and which extend up to amplitudes slightly more than 160
> mJy.
> 
> Are these features examples of bad points that have to be flagged?
> 
> Thanks
> 
> Johan
> 
> 
> 
>   ------------------------------------------------------------------------
>                 Name: file1.uue
>    file1.uue    Type: Plain Text (TEXT/PLAIN)
>             Encoding: BASE64