3 papers
astro-ph2004
Chandra Observations of low velocity dispersion groups
Stephen F. Helsdon, Trevor J. Ponman, J. S. Mulchaey
Deviations of galaxy groups from cluster scaling relations can be understood in terms of an excess of entropy in groups. The main effect of this excess is to reduce the density and…
astro-ph2002
The morphology-density relation in X-ray bright galaxy groups
Stephen F. Helsdon, Trevor J. Ponman
We have examined the morphological make-up of X-ray bright groups. The brighter galaxies in these groups exhibit clear morphology-density and morphology-radius relations. The group…
astro-ph2002
X-ray bright groups and their galaxies
Stephen F. Helsdon, Trevor J. Ponman
Combining X-ray data from the ROSAT PSPC and optical data drawn from the literature, we examine in detail the relationship between the X-ray and optical properties of X-ray bright…