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Observing time estimates

Observing time estimates must take into account:

For bolometer observations, integration time estimators are available in the NIC software [11]. For heterodyne observations, the total integration time should be derived using the standard radiometer formula:


where tex2html_wrap_inline1320 and tex2html_wrap_inline1322 are the telescope forward and main beam efficiencies, tex2html_wrap_inline1324 is the system temperature above the atmosphere (in the antenna temperature scale), B the channel noise bandwidth in Hz, and t the total (ON + OFF) integration time in seconds. For 3, 2, and 1.3mm observations, tex2html_wrap_inline1324 should be estimated for average winter conditions (4 mm of precipitable water, or tex2html_wrap_inline1332 at 230 GHz). Proposals for 0.8mm should adopt good winter conditions (1.5 mm of water, or tex2html_wrap_inline1334 at 345 GHz).

We ask you to specify in your proposal the parameter values ( tex2html_wrap_inline1336 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 issuegif 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.