A1447 2000-May-27 15:36:30 Technical Page Proposal Type: Regular General Category: Astronomy Sub-Category: Spectroscopy Observation Category: Galactic Total Time Requested: 5 Hours Proposal Title: HI Self-Absorption study of B5 and L1544 ABSTRACT: We propose observing atomic hydrogen inside dark clouds through 21 cm self-absorption. ... With highest angular resolution and nest velocity resolution of HI dark-cloud maps ever achieved, the data set will reveal velocity structure and column density in HI. ...

... 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. ...