Astrophysics 405 Homework Assignment 4 Tully­Fisher Galaxies in the Expanding Universe Due 1999 April 15 This assignment is a ``dry lab'' simulation of a galaxy observation project. ... Images, spectra, and apparent magnitudes mB for a collection of nearby galaxies have been provided. ... For those galaxies you are unable to classify, assume type Sc. (g) Compute the T­F distance for each galaxy. ... 2 Galaxy Data Use the following data in your calculations. There are 32 galaxies in this sample. ...

... 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. ...