Galaxy clusters in the Perseus-Pisces region -- I. Spectroscopic and photometric data for early-type galaxies

We present new spectroscopic and photometric data for 137 early-type galaxiesin nine clusters, and for a set of nearby standard galaxies. The clustersstudied are Perseus (A0426), Pisces, A0262, A0347, J8, HMS0122+3305, 7S21,A2199 and A2634. Our spectroscopic data comprise radial velocities (cz),central velocity dispersions (sigma) and magnesium line strength indices (Mg).Internal errors (derived from repeat observations) are 7.6% on each measurementof sigma, and 0.010 mag on each Mg measurement. We correct the major publisheddatasets to a standard aperture size, and define a new `standard system' by theaperture-corrected Lick data of Davies et al. Through extensiveintercomparisons with data from the literature, we present the correctionsrequired to bring the major published datasets onto the standard system. Wedemonstrate that our new velocity dispersion data can be brought intoconsistency with the standard system, to an uncertainty of <0.01 dex. FromR-band CCD photometry, we derive effective diameter (A_e), mean surfacebrightness within effective diameter (mu_e) and an R-band diameter equivalentto the D_n parameter of Dressler et al. Internal comparisons indicate anaverage error of 0.005 in each measurement of log(D_n). The combinationlog(A_e) - 0.3 mu_e, approximately the quantity used in the Fundamental Planedistance indicator, has an uncertainty of 0.006 per measurement. Thephotometric data can be brought onto a system consistent with external data atthe level of 0.5% in distance. These data will be used in a companion paper toderive distance and peculiar velocity estimates for the nine clusters studied.(Abridged)