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Multiple merging in the Abell cluster 1367

L. Cortese·G. Gavazzi·A. Boselli·J. Iglesias-Paramo·L. Carrasco
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Abstract

We present a dynamical analysis of the central ~1.3 square degrees of the cluster of galaxies Abell 1367, based on 273 redshift measurements (of which 119 are news). From the analysis of the 146 confirmed cluster members we derive a significantly non-Gaussian velocity distribution, with a mean location C_{BI} = 6484+/-81 km/s and a scale S_{BI} = 891+/-58 km/s. The cluster appears elongated from the North-West to the South-East with two main density peaks associated with two substructures. The North-West subcluster is probably in the early phase of merging into the South-East substructure (~ 0.2 Gyr before core crossing). A dynamical study of the two subclouds points out the existence of a group of star-forming galaxies infalling into the core of the South-East subcloud and suggests that two other groups are infalling into the NW and SE subclusters respectively. These three subgroups contain a higher fraction of star-forming galaxies than the cluster core, as expected during merging events. Abell 1367 appears as a young cluster currently forming at the intersection of two filaments.

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L. Cortese, G. Gavazzi, A. Boselli, J. Iglesias-Paramo, L. Carrasco. 2004-06-16. Multiple merging in the Abell cluster 1367. https://doi.org/10.1051/0004-6361%3A20040381

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