ALMA SIS14 apcal

Phase Calibration (per Scan)

First, we calibrate phase as a function of time.

# In CASA
listobs("sis14_ampandphase.ms")

Now we calibrate the phase correction for each antenna as a function of time.

# In CASA
os.system("rm -rf phase.cal")
gaincal(vis="sis14_ampandphase.ms",
        caltable="phase.cal",
        field="0",
        solint="inf",
        calmode="p",
        refant="DV22",
        gaintype="G")

Now we plot the results of the calibration.

# In CASA
plotcal(caltable="phase.cal", 
        xaxis="time",
        yaxis="phase",
        subplot=331,
        iteration="antenna",
        plotrange=[0,0,-180,180])

Amplitude Calibration (per Scan)

Now calibrate the amplitude response of each antenna as a function of time.

# In CASA
os.system("rm -rf amp.cal")
gaincal(vis="sis14_ampandphase.ms",
        caltable="amp.cal",
        field="0",
        solint="inf",
        calmode="a",
        refant="DV22",
        gaintype="G",
        gaintable="phase.cal")

Plot the results of this fit.

# In CASA
plotcal(caltable="amp.cal", 
        xaxis="time",
        yaxis="amp",
        subplot=331,
        iteration="antenna",
        plotrange=[0,0,0,0])

Phase and Amplitude Calibration (per Integration)

We can also solve for the antenna corrections on shorter timescales.

# In CASA
os.system("rm -rf apcal_int.cal")
gaincal(vis="sis14_ampandphase.ms",
        caltable="apcal_int.cal",
        field="0",
        solint="int",
        calmode="ap",
        refant="DV22",
        gaintype="G")

Plot the per-integration variation of the phase.

# In CASA
plotcal(caltable="apcal_int.cal", 
        xaxis="time",
        yaxis="phase",
        subplot=331,
        iteration="antenna",
        plotrange=[0,0,-180,180])

Now plot the per-integration variation of the amplitude.

# In CASA
plotcal(caltable="apcal_int.cal", 
        xaxis="time",
        yaxis="amp",
        subplot=331,
        iteration="antenna",
        plotrange=[0,0,0,0])