... RA (Dec) Offset & Strip Time: These parameters not only define the size of your map in the RA (Dec) direction in arcmin, but also, when combined with the strip time, set the drive rate on the sky; i.e., the RA drive rate is set to 2 60 (RA offset)/(Strip time) [in arcsec/sec]. The type of arcsecond (little circle or great circle) is set by the RA offset type (see below), or a Dec drive rate of 2 60 (Dec offset)/(Strip time) for the Dec/RA map option. ...

... 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. ...