Exposure Time Calculator

Choosing File $\rightarrow$ Exposure Time Calculator... in the OT Menu bar will launch a separate window which provides a simple interface to the Exposure Time Calculator for ALMA observations. The ETC can also be launched from the Spectral Form of a RegionofInterest in the Science View. It implements a realistic but simple formula for the estimation of ALMA exposure time to reach a given sensitivity for unresolved (point) sources or a limited surface brightness sensitivity for extended sources. The ETC also provides the inverse facility, estimated sensitivity given an input exposure time. It makes use of a first version of the Observatory Receiver Expert (to obtain estimates of receiver system temperatures).

Figure 2: The Exposure Time Calculator
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The ALMA OT Team, 2012 May 25