setting the phase corrections to zero.
WARNING: if you modify the gains, the resulting amplitude gains will be
constant with time! The original gains table is overwritten.
The motivation for this routine arose from BIMA datasets in which the calibrator is weak so that conventional amplitude calibration was not very successful. This was compounded by old BIMA ant3 being blown about by the wind. The source, on the other hand, was strong but time variable, hence not susceptible to self-cal. From observations of strong planets before and after it was observed that the amplitude scale was reasonably stable, and certainly more stable than implied by the phase-calibrator data, so that only phase calibration really needs to be applied to the source. This program allows the amplitude scale to be forced to the desired values (in this case, obtained from the planet observations) without changing the phase calibration.
This routine is specific to CARMA, hardcoded for 15 antennae.
The mean, median and rms (about the mean) are reported.phase List the phase corrections. complex List complex gains for 10 antennas only (2 lines per soln) all List all complex gains (one line per antenna per solution
for all antennas; lots of output, better than options=complex if you want to grep one one antenna.)replace Replace the amplitude gains with the list supplied
Unless OPTIONS=FORCE is also set, only antennas with non-zero values in the list are affected so if jyperk is not set, nothing happens. Phases are preserved unless options=zerophas is also specifiedforce If set, then all values in jyperk are enforced when
doing a replace, even if they (or the initial gains) are zerolimit Impose an upper limit on the amplitude gains using the
list specified in jyperkmultiply Multiply existing sqrt(Jy/K) values in a gains table by
the list supplied in the jyperk variable. Only antennas corresponding to nonzero jyperk elements are changed. No effect on phases.zerophas Zero all phase corrections (no antenna selection method) addphase Correct gains by antenna based phases supplied in the
jyperk array, units degrees. Note that these phases are added to the existing phase gains, except when OPTIONS=ZEROPHAS is also used.clip Set to zero all gains outside range jyperk(1),jyperk(2)
Useful for pseudo-flagging of bad data, e.g., gplist vis=dummy options=clip jyperk=0.5,2.0 effectively flags data with gains outside 0.5-2 (default range). However, data are not really flagged. The next option is an alternative "flagging" option.sigclip Set to zero all gains more than jyperk(1)*rms away from
median on each antenna
Use options=replace,zerophas with suitable jyperk list to both set amp scale and zero phases (the two steps are carried out sequentially with the amplitudes being set first)
Use options=addphase to add phases to the existing ones.
Use options=addphase,force to replace phases.