C.1 Quick Guide

This section is meant as a reminder for people who have some idea how to reduce straightforward VLBI data and a familiarity with AIPS. For further details see the rest of this appendix and/or Chapter 9. This section does not include things like CVEL or AVSPEC that might be useful for spectral line observations. Also, this section refers to procedures that can loaded by typing RUN VLBAUTIL. All these steps are also performed by the VLBARUN (section C.5) pipeline procedure.

  1.  VLBALOAD — load the data
  2.  VLBAFIX — fix the data (separate frequencies, merge tables, create index table, etc.)
  3.  VLBAEOPS — correct earth orientation parameters
  4.  VLBATECR — (if frequency < 10 GHz) remove dispersive delay from ionosphere
  5.  VLBACCOR — correct sampler threshold errors from correlator
  6.  VLBAPCOR or VLBAMPCL — (if more than 1 IF) correct instrumental delays, use POSSM to inspect correction
  7.  VLBABPSS — calibrate bandpass, use POSSM to inspect bandpass solutions
  8.  VLBAAMP — corrects any auto-correlation departure from unity caused by previous steps and performs a-priori amplitude calibration, use SNPLT to check that nothing has gone wrong in the amplitude calibration.
  9.  VLBAPANG — correct parallactic angle
  10.  VLBAFRNG or VLBAFRGP — fringe fit data
  11.  SPLIT — apply all calibration and possibly average data spectrally
  12.  IMAGR — image data