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We have been conducting a full sky survey of galaxies in nearby Abell clusters (z $<$ 0.04). This project has three main objectives. We wish to study the dependence of the mass--to--light distributions upon cluster density by comparing core galaxies to periphery and low density region members. We are also examining the relationship between radio and optical velocity widths to calibrate radio and optical Tully--Fisher relations. This validates within our sample a substantial number of galaxies with valid H$\alpha$ and [NII] rotation curves but no detectable HI line profile. We can thus derive Tully--Fisher distances to the clusters based upon the total sample in order to examine deviations from Hubble flow beyond the region dominated by the effects of the Local Supercluster and the Great Attractor.
We have used the Double Spectrograph on the Palomar 5--meter telescope to obtain 250 optical rotation curves in 11 clusters, with an additional 30 field galaxies at comparable distances. We have extracted velocity widths to better than 10 km/s. Over 500 HI line profiles have been acquired for galaxies observable from Arecibo Observatory, including all of the sources in the Palomar sample. I--band images have been taken with the KPNO 0.9--meter telescope for the complete sample. Preliminary results show a clear linear relationship with a small offset between optical and radio widths, and good agreement in deriving Tully--Fisher distances to clusters. We will present a representative sample of the rotation curve study and discuss the initial results of data analysis.
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