Structure and Dynamics of the Coma Cluster
| dc.creator | Colless, Matthew | |
| dc.creator | Dunn, Andrew M. | |
| dc.date | 1995-08-16 | |
| dc.date.accessioned | 2026-07-07T11:08:21Z | |
| dc.date.available | 2026-07-07T11:08:21Z | |
| dc.description | We examine the structure and dynamics of the galaxies in the Coma cluster using a catalog of 552 redshifts including 243 new measurements. The velocity distribution is shown to be non-Gaussian due to structure associated with the group of galaxies around NGC4839, 40 arcmin SW of the cluster core. We apply a mixture-modelling algorithm to the galaxy sample and obtain a robust partition into two subclusters which we use to examine the system's dynamics. We find that the late-type galaxies are freely-falling into a largely virialised cluster core dominated by early types. We obtain a virial mass for the main cluster in close agreement with the estimates derived from recent X-ray data. The mass of the NGC4839 group is about 5-10% the mass of the main cluster. Assuming the main cluster and the NGC4839 group follow a linear two-body orbit, the favored solution has the two clusters lying at 74 degrees to the line of sight at a true separation of 0.8 Mpc and moving together at 1700 km/s. The cluster core shows evidence of an ongoing merger between two subclusters centered in projection on the dominant galaxies NGC4874 and NGC4889 but offset in velocity by 300 km/s and 1100 km/s respectively. Combining these results with X-ray and radio observations, and an interpretation of the presence or lack of an extended halo around the dominant galaxies, we develop a merger history for the Coma cluster. | |
| dc.description | To appear in Ap.J., 43 pages, Postscript of text only, see http://msowww.anu.edu.au/~colless/Preprints/coma.html for text, tables and figures | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9508070 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9508070 | |
| dc.identifier | Astrophys.J.458:435,1996 | |
| dc.identifier | doi:10.1086/176827 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/190108 | |
| dc.subject | Astrophysics | |
| dc.title | Structure and Dynamics of the Coma Cluster | |
| dc.type | text |