Proposal Identification No.: T1937 Date Received: 2004­Feb­02 15:07:54 Technical Page Proposal Type: Regular General Category: Terrestrial Aeronomy Observation Category: Ionosphere Total Time Requested: 48 Hours Proposal Title: Ionospheric disturbances resulting from Atlantic tropical storms and hurricanes ABSTRACT: Recent observations have shown a possible connection between the occurrence of hurricanes and tropical storms and F­region range spreading and velocity variations. ...

... 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. ...