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Appendix 2: Calibration data questions

Providing calibration data for EVN experiments - some questions
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(as asked from a user's point of view by Richard Porcas !)

a) Is it correct ?
   -------------
   Correct gain-curve ?
   Correct K/Jy ?
   Correct calibrator fluxes used ?
   Correct noise-source value used for Tsys measurements ?

b) Is it complete ?
   --------------
   Can the PI reconstruct T/(K/Jy) for every scan (for both 
   polarisations) ?
   - appropriate data provided for both polarisations, if needed ?
   - appropriate combination of Tsys, Tnoise, gain, etc provided ?
   - data provided for both Mark2 and Mark3 experiments ?
   - special requirements for spectral line experiments ?

c) How accurate are the measurements ?
   ---------------------------------
   How accurate is the derived ratio T/(K/Jy) ?
   Is a sensible noise-source value used ?
   Would continuous Tsys measurements help ?
   Are there any peculiar bandpasses ?
   Would channel(i.e.vc)-specific calibration help ?
   How large are the polarisation cross-talk terms ?
   Are there likely to be coherence losses ?
   Are there special features of your antenna (eg phased arrays) which
   the PI has been informed about, which affect calibration ?

d) How easily can the PI access the data ?
   -------------------------------------
   How quickly is it "available" ?
   Where is it available ? (ASTBO1 ? Correlator ? Home institute ?)
   How easily can the data be read into the appropriate post-correlation
       analysis programs ?
   How much hand-editing of files by the PI is necessary ?
   How does the PI know how to interpret and use the data from YOUR  
       observatory ?
   Why not try to feed the calibration data from YOUR observatory
      into e.g. AIPS (via ANCAL) ,with the help of a local astronomer
      if needed ? Could this task have been made easier ?