Observing time estimates must take into account:

- integration time on source and comparison field(s), including overheads for ON/OFF telescope motions, deadtime for device switching and data transfer.
- pointing, focus, continuum and line calibrations
- telescope slew motions
- receiver tunings (for heterodyne observations),

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 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 in Hz, and *t* the total (ON + OFF) integration time
in seconds.
For 3, 2, and 1.3mm observations,
should be estimated for *average* winter conditions
(4 mm of precipitable water, or at 230 GHz).
Proposals for 0.8mm should adopt *good* winter conditions
(1.5 mm of water, or at 345 GHz).

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*.

guelin@iram.fr