Mj. Hudson et al., Streaming motions of galaxy clusters within 12 000 km s(-1) - III. A standardized catalogue of Fundamental Plane data, M NOT R AST, 327(1), 2001, pp. 265-295
We report the construction of a new, standardized all-sky catalogue of Fund
amental Plane (FP) data from early-type galaxies in clusters, for peculiar
velocity applications. This catalogue is based on a compilation of spectros
copic and photometric data consisting of data reported in previous papers o
f this series, plus data from published sources. We compare velocity disper
sion and Mg-2 line-strength data from 27 sources, and determine the correct
ions that bring, all data sets on to a standardized system. For the velocit
y dispersions, the corrections are typically at the level of similar to0.01
5 dex, corresponding to 5 per cent in the FP-estimated distance. The uncert
ainties in these corrections, however, are considerably smaller: the new da
ta obtained by our group are closely matched on to the standard system, wit
h systematic uncertainties at the level of similar to0.005 dex in velocity
dispersion (<2 per cent in distance). In this respect our catalogue signifi
cantly improves upon previously published FP data sets. For the Mg2 line-st
rength index, corrections are typically at the level of 0.01 mag, but the u
ncertainties in these corrections are only <similar to>0.002 mag.
A similar procedure is employed to compare photometric data from nine diffe
rent sources, correcting for the average colours of early-type galaxies. We
focus on the combination of parameters appearing in the FP, X-FP = log R-e
- 0.32 [mu](e), where R-e and [mu](e) are the effective radius and effecti
ve surface brightness, respectively. For the data sets considered here we s
how that no further corrections are required to X-FP, given the typical sys
tematic zero-point uncertainties per data source (0.003-0.006 dex, or 0.7-1
.4 per cent in distance). Finally, we use redshift data to assign galaxies
to clusters in an objective way.
We present a master catalogue of FP data for 699 galaxies in 56 clusters, t
he largest high-quality data set of its kind. These data will be used in fu
ture papers to determine the distances and peculiar velocities of these clu
sters, and thus probe the peculiar velocity field within 12 000 km s(-1).