9.2 Planning GREAT Observations

The Guide to Observation Planning with GREAT (GOPG) describes the GREAT instrument and the available observing modes. The information required to estimate observing times in each mode, along with examples on how to do so, are also contained in the GOPG.

Note that the sensitivity calculations for PSW and BMSW modes are the same. In the case of OTF mapping, the sensitivity reached depends on the scan rate and the overlap between successive rows. Information on how to plan OTF mapping observations can be found in the Guide to Planning OTF Maps with the upGREAT Array document.

If the frequency of interest has not already been used by GREAT, please contact the GREAT team to ensure that the line is feasible. There may be gaps where the broadband Local Oscillators do not provide enough power to pump the mixers.

9.2.1 Estimating Exposure Time

The exposure times for GREAT observations may be estimated using the Online Calculator.