Proposal Identi cation No.: A1969 Date Received: 2004-May-28 00:06:53 Technical Page Proposal Type: Regular General Category: Astronomy Sub-Category: Spectroscopy Observation Category: Galactic Total Time Requested: 200 Hours Proposal Title: Tracing high-mass star formation in the Galaxy ABSTRACT: Theoretical and observational studies have revealed that the 6.668 GHz methanol masers are precursors of ultracompact HII regions, and are excellent tracers of high-mass star formation. ...

... 2.3 Data acquisition Spectra generated by the Multibeam correlator contain the usual structure seen in spectra from other H i instruments: a bandpass spectrum which is the sum of the sky , ground and receiver temperatures multiplied by the product of the filters in the receiver chain; superimposed on this is a noise ... Note also that sources extended much beyond ,40 arcmin can be imaged poorly in HIPASS images because of the bandpass sidelobe effect described in Section 3.3. ...