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Correct for Bandpass Ripples

The Miriad task smatbpass removes time-dependent bandpass ripples. smatbpass reads multiple files (bpfile) containing antenna-based bandpass solved using either smamfcal or mfcal in time intervals at different time. The bandpasses are interpolated or extrapolated to a time with either linear fit from the two nearby solution points or orthogonal polynomial fit from all the solution points in the input bpfiles. Here is a usage of smatbpass:

 Task:   smatbpass
  bpfile   = 05aug1bp                  % root name of input files
                                         each of which contains
                                         bandpass solutions in
                                         the bandpass table at the
                                         corresponding time in the
                                         gain table.
  nfiles   = 3                         % The number of bandpass files
                                         (bpfile) to read.
  vis      = sgrb228a_rx0.lsb.tsys     % The name of the input uv data
                                         sets.
  bptime   = 30                        % The time interval, in minutes,
                                         to interpolate/extrapolate the
                                         bandpass solutions.
  options  = nocal                     % extra options
  out      = sgrb228a_rx0.lsb.tsys.bp  % The name of the output uv data
                                         set which has been applied
                                         for bandpass correction.

The visibility data in output file sgrb228a_rx0.lsb.tsys.bp has been corrected for the bandpass ripples.



Jun-Hui Zhao (miriad for SMA)
2012-07-09