Flagging the beginning of scans

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3.6.1.2 Flagging the beginning of scans

You can use quack=True to drop integrations from the beginning of scans (as in the AIPS task QUACK):

quack               =       True        #  Clip beginning or ending of scans
     quackinterval  =        0.0        #  Quack n seconds from scan beginning/end
     quackmode      =      ’beg’        #  Quack mode. ’beg’ ==> beginning of scan. ’endb’ ==>
                                        #   end of scan. ’end’ ==> all but end of scan. ’tail’
                                        #   ==> all but beginning of scan
     quackincrement =      False        #  Flag incrementally in time?

Note that the time is measured from the first integration in the MS for a given scan, and this is often already flagged by the online system.

For example, assuming the integration time is 3.3 seconds (e.g. for VLA), then

quack = True
quackinterval = 14.0

will flag the first 4 integrations in every scan.

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