A SOUTHERN SKY SURVEY OF THE PECULIAR VELOCITIES OF 1355 SPIRAL GALAXIES

The data from photometric and spectroscopic observations of 1355 southern spiral galaxies are presented and used to determine their distances and peculiar velocities via the Tully-Fisher (TF) relation. I-band CCD surface photometry was carried out using the 1 m and 3.9 m telescopes at Siding Spring Observatory. The GASP software of M. Cawson was used to reduce the CCD images. Luminosity profiles are presented for the 1355 galaxies. H-alpha and H I spectroscopy were carried out using the dual-beam spectrograph on the 2.3 m telescope at Siding Spring Observatory and the 64 m Parkes radio telescope of CSIRO, respectively. H-alpha-rotation curves for 965 galaxies and 551 H I profiles are presented. A comparison of the results of measuring the projected velocity of rotation of spiral galaxies by the two different techniques is made. The Fornax cluster was used to calibrate the Tully-Fisher relation. All distances are measured relative to the Fornax cluster whose distance was taken to be 1340 km s-1. There is no sign of nonlinearity in the TF relation. Table 1 contains the physical parameters, photometric and velocity data, distances, and peculiar velocities of the galaxies. Tests indicate that the corrections for extinction in our Galaxy and the internal extinction in the galaxies are correct. There does not appear to be a dependence on morphological type. Malmquist bias is found to be not very sensitive to the space distribution of galaxies encountered within the survey region. The "zero-velocity" H I was observed in the direction of each galaxy using the 64 m radio telescope at Parkes and used to measure the extinction in our Galaxy following the method of Burstein & Heiles. Table 2 lists the member galaxies of the 24 clusters in the sample, some previously known, others identified by the proximity in space of a number of galaxies. The mean distance, systemic velocity, and peculiar velocity of each cluster are given. Tully-Fisher diagrams are presented for each cluster. The average of the scatter in the Tully-Fisher relation for the seven most populous clusters is 0.32 mag, which gives an accuracy of +/- 16% for the distance measurements. A comparison with other distance measurements shows that on average our distances are 4% lower than the distances given in the Burstein data set which is based on a distance to the Coma Cluster of 7380 km s-1. A magnetic tape containing Table 1, Table 2, the luminosity profiles, the H I profiles, and the H-alpha-rotation curves is available on request.