# In CASA default(plotms) vis='sis14_twhya_calibrated_flagged.ms' xaxis='time' yaxis='amp' avgchannel='384' avgtime='30s' field='TW Hya' uvrange='<50' coloraxis='baseline' plotms
Use select and locate to identify the bad data. Look in the logger. The fragment below shows the important details: In scan 16, all the bad data involve antenna DV19 and in scan 36, all the bad data involve DV20.
Scan=16 Field=TW Hya[5] Time=2012/11/19/08:08:24.7 BL=DV08@A021 & DV19@A008[14&21] Scan=16 Field=TW Hya[5] Time=2012/11/19/08:08:24.7 BL=DV19@A008 & DV22@A011[21&24] Scan=16 Field=TW Hya[5] Time=2012/11/19/08:08:24.7 BL=DV19@A008 & DV23@A007[21&25] Scan=36 Field=TW Hya[5] Time=2012/11/19/09:05:30.7 BL=DA48@A046 & DV20@A020[5&22] Scan=36 Field=TW Hya[5] Time=2012/11/19/09:05:30.7 BL=DV06@A037 & DV20@A020[12&22] Scan=36 Field=TW Hya[5] Time=2012/11/19/09:05:30.7 BL=DV08@A021 & DV20@A020[14&22]
Use flagdata to flag the first set of bad data:
# In CASA default(flagdata) vis='sis14_twhya_calibrated_flagged.ms' antenna='DV19' scan='16' inp flagdata
You can see the flagging progress in the logger. Now change the parameters values to specify the other bad data noted above. If you also enter these (and further values you have to fill in) in twhya.py, you will have a script you can run later.
# In CASA default(flagdata) vis='sis14_twhya_calibrated_flagged.ms' antenna='**' # The other bad antenna scan='**' # The other bad scan inp flagdata
Check in plotms by ticking the reload button at the bottom and press plot. Then set the x-axis to channel and remove the uv range and channel averaging, but average all times, scans and baselines (see figure below). You can see a hint of a line but it so faint we can ignor it and average all channels for initial continuum imaging.
amsr@jb.man.ac.uk 15 Oct 2015