gc.contcal(tcal=1.0,average=T,baseline=F,nfit=0,range=20)

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gc.contcal(tcal=1.0,average=T,baseline=F,nfit=0,range=20)

contcal performs the basic calibration on the data. It has arguments for tcal (to over-ride the system determined value). The default is to average all polarizations (as available); this can be toggled off by setting average=F. Optionally, a baseline can be subtracted from each row of the data. The range argument determines the beginning and end percentage of each scan row that will be used for the baseline determination; the default is 20%.

The initial continuum maps obtained at the GBT are four phase data representing the states of noise-diode off and on for two separate receptors. contcal performs the following calculation for each OTF strip of the map:

T_ANT = T_CAL x $\displaystyle {\frac{{V_{ON} + V_{OFF}}}{{2 \times <V_{ON} - V_{OFF}>}}}$ - < T_CAL/2. > (5.1)

V_ON are the counts for the CAL ON phase
V_OFF are the counts for the CAL OFF phase
T_CAL is the K/counts conversion

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