2001ApJ...548..550N

We present an investigation of the dynamical state of the cluster A262. Existing optical line-of-sight velocities for select cluster galaxies have been augmented by new data obtained with the Automated Multi-Object Spectrograph at Lick Observatory. We find evidence for a virialized early-type population distinct from a late-type population infalling from the Pisces-Perseus supercluster ridge. We also report on a tertiary population of low-luminosity galaxies the velocity dispersion of which distinguishes them from both the early- and late-type galaxies. We supplement our investigation with an analysis of archival X-ray data. A temperature is determined using ASCA GIS data, and a gas profile is derived from ROSAT HRI data. The increased statistics of our sample results in a picture of A262 with significant differences from earlier work. A previously proposed solution to the ``β-problem'' in A262 in which the gas temperature is significantly higher than the galaxy temperature is shown to result from using too low a velocity dispersion for the early-type galaxies. Our data present a consistent picture of A262 in which there is no ``β-problem'', and the gas and galaxy temperature are roughly comparable. There is no longer any requirement for extensive galaxy-gas feedback to drastically overheat the gas with respect to the galaxies. We also demonstrate that entropy floor models can explain the recent discovery that the β values determined by cluster gas and the cluster core radii are correlated.