... 1987A(IIP), 1993J(IIb), 2001gd(IIb) Science : Explosion Dynamics Evolution of the Circumstellar Medium ( CSM ) Needs : Sensitivity , High Resolution (~1 mas), Repetitive Monitoring Early Density Structure of the CSM Absorption Mechanisms 20cm-cyan 6cm-blue 3.5cm-green 2cm-red 1.3cm-black SN 1994I - type Ic Synchrotron Self Absorption Science : Progenitor Mass-Loss Rates Evolution of the Circumstellar Medium ( ... Progenitor & CSM Evolution Needs: Improved Sensitivity, ~1" Res.,...

... 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. ...