the efficiency ratio (integration time/observing time) is .
RASTER 84 6 0 6/REF 3600 0/ON 2/T 30 45,
the calculation gives:
and R= 0.78.
Note that the measured average time for such a raster scan was actually 1050 s and R= 0.74.
i.e. , or 2500s (0.7h), to which you may add your own reaction time, typing time, etc...
In total, in this typical PSW mode, you can expect to observe in 3 hours (10800 s) about (10800-2500)/ scans (total 7000s (2h)). The observing `efficiency' is thus only .
In the Wobbling mode, these numbers would drop to 21 scans, s and . (You could increase them somewhat by setting set subs 12).
The following preparation costs about 0.4 hours:
First slew to the source: 5 min
Skydip: 5 min
Observation of a Line Calibrator: 15 min (with slew)
Observations: 6 h (including 3.7 to 3.9 h of integration ON+OFF source, see example C above).