Ph.D. Description
H. Patrick Murphy
(Now Patrick P. Murphy)
Awarded January 1983 by
The National University of Ireland
- Title
- A comparison of Optical and X-ray properties of Selected Clusters of
Galaxies
- Advisors
- N.A. Porter, University College,
Dublin (National University of Ireland)
P.A. Wayman, Dunsink
Observatory, Dublin
Institute for Advanced Studies
T.C. Weekes, Smithsonian
Astrophysical Observatory (
F.L. Whipple Obs., Tucson)
- Abstract
- CCD Cameras are used to investigate the optical properties of
clusters of galaxies in the context of their X-ray properties and
appearance. A new cluster classification based on both optical
and X-ray appearance (the Forman-Jones scheme) is discussed in
the light of the new CCD observations. The properties of the CCD
cameras used are investigated and described, and the suitability
of this device for extragalactic research is reviewed. The
optical study is reported in two parts. Firstly, the brightest
member galaxies in 35 rich Abell clusters were observed and
analysed, resulting in confirmation of the known small dispersion
in Magnitudes of these objects, and the possibility of a relation
between X-ray and optical luminosity. Secondly, detailed
observations were made in two colours of the X-ray emitting
regions of three clusters at different evolutionary stages.
These observations indicate general agreement with the new
classification scheme but some discrepancies were found. The
central regions of the unevolved cluster A262 have a very high
galaxy density, and the evolved cluster A85 is shown to have a
peculiar colour distribution. These discoveries indicate a need
for more detailed observations.
- Related Publications
-
- P. Murphy and T.C. Weekes, CCD camera observations of
nearby rich clusters--III. Results and analysis for six
clusters, in perpetual preparation (probably will
never be finished, the data quality isn't that good
anymore compared to modern CCD data).
- H.P. Murphy, CCD camera observations of nearby rich
clusters--II. Techniques and results for A85,
Mon. Not. R. Astr. Soc. 211, 637
(1984).
- H.P. Murphy, R.E. Schild, and T.C. Weekes, CCD camera
observations of nearby rich clusters--I. R photometry of
brightest galaxies, Mon. Not. R. Astr. Soc.
202, 1127 (1983).