| Texto completo | |
| Autor(es): |
Lima Neto‚ GB
;
Capelato‚ HV
;
Sodré Jr‚ L.
;
Proust‚ D.
Número total de Autores: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Astronomy & Astrophysics; v. 398, n. 1, p. 31-39, 2003. |
| Resumo | |
We report new results on the cluster of galaxies Abell 970 obtained from X-ray observation with BeppoSAX. Our analysis of the BeppoSAX MECS and LECS data in the range [0.15-10] keV reveals a mean cluster gas temperature of kT = 4.46(-0.15)(+0.14), a metallicity of Z = 0.31(-0.04)(+0.05) Z., and an interstellar hydrogen absorption column density of N-H = 6.05(-0.97)(+1.29)x10(20) cm(-2). Moreover, we obtained azimuthally averaged radial profiles of these quantities. Our results are consistent with the hypothesis that Abell 970 has been disturbed by a past merger or by the ongoing merger process of a substructure, that put the cluster out of equilibrium. This is also demonstrated by the offset between the gas and galaxy distributions. Combining the X-ray data with a recently published analysis of new galaxy radial velocities, we conclude that a subcluster 8 arcmin to the NW is falling into Abell 970 and will merge in a few Gigayears, thus disturbing Abell 970's newly acquired equilibrium. The high alpha-elements/iron ratio that we derive for this cluster supports the hypothesis of early intracluster medium enrichment by Type II supernovae. (AU) | |
| Processo FAPESP: | 00/06770-2 - Radiação cósmica de fundo em microondas e formação de estruturas no universo |
| Beneficiário: | Reuven Opher |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 00/06695-0 - Evolução e atividade de galáxias |
| Beneficiário: | Ronaldo Eustaquio de Souza |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |