Observing time estimates

Observing time estimates must take into account:

• receiver tunings (for heterodyne observations),
• pointing, focus, continuum and line calibrations (be aware that receiver alignment corrections, if needed, will eventually be counted against your observing time),
• telescope motions when changing sources as well as dead times due to telescope motion and/or data writing between ON and OFF subscans,
• integration time on source and comparison field(s).

The total integration time should be derived using the standard formula:

where and are the telescope forward and main beam efficiencies, is the system temperature above the atmosphere (in the antenna temperature scale), B the channel noise bandwidth, and t the total (ON + OFF) integration time. should be estimated for an `average' summer humidity for 3mm, 2mm and 1.3mm observations (7 mm of precipitable water, or at 145 GHz and 0.5 at 230 GHz, see Table 4.2 of the 30-m telescope Manual [10]).

We ask you to specify in your proposal the parameter values ( total integration time, overheads and dead times) adopted in your calculation of the needed telescope time.

A technical report explaining how to estimate the telescope time needed to reach a given sensitivity level in various modes of observation was published in the January 1995 issue of the IRAM Newsletter [9] . It has been included in the 30-m telescope Manual [10]. You are asked to follow the guidelines given in this report (or to justify particular requirements) in your proposal.