Large scale diffuse light in the Coma cluster: a multi-scale approach

C. Adami (1) , E. Slezak (2) , F. Durret (3) , C. J. Conselice , J. C. Cuillandre , J. S. Gallagher , A. Mazure (1) , R. Pello (4) , J. P. Picat (4) , M. P. Ulmer

1 LAM - Laboratoire d'Astrophysique de Marseille
2 CASSIOPEE - Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides
3 IAP - Institut d'Astrophysique de Paris
4 UMS 831 - Services communs OMP

We have obtained wide field images of the Coma cluster in the B, V, R and I bands with the CFH12K camera at CFHT. In order to search for large scale diffuse emission, we have applied to these images an iterative multi scale wavelet analysis and reconstruction technique which allowed to model all the sources (stars and galaxies) and subtract them from the original images. We found various concentrations of diffuse emission present in the central zone around the central galaxies NGC4874 and NGC4889. We characterize the positions, sizes and colors of these concentrations. Some sources do not seem to have strong star formation, while another one probably exhibits spiral-like color. One possible origin for the star forming diffuse emission sources is that in the region of the two main galaxies NGC4874 and NGC4889 spiral galaxies have recently been disrupted and star formation is still active in the dispersed material. We also use the characteristics of the sources of diffuse emission to trace the cluster dynamics. A scenario in which the group around NGC 4874 is moving north is consistent with our data.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Astrophysique [astro-ph]

C. Adami, E. Slezak, F. Durret, C. J. Conselice, J. C. Cuillandre, et al.. Large scale diffuse light in the Coma cluster: a multi-scale approach. Astronomy and Astrophysics - A&A, 2005, 429, pp.39-48. ⟨hal-00005094⟩