Unusual A2142 supercluster with a collapsing core: distribution of light and mass
Abstract
Context. Superclusters of galaxies can be used to test cosmological models of the formation and evolution of the largest structures in the cosmic web, and of galaxy and cluster evolution in superclusters.
Aims: We study the distribution, masses, and dynamical properties of galaxy groups in the A2142 supercluster.
Methods: We analyse the global luminosity density distribution in the supercluster and divide the supercluster into the high-density core and the low-density outskirts regions. We find galaxy groups and filaments in these regions, calculate their masses and mass-to-light ratios and analyse their dynamical state with 1D and 3D statistics. We use the spherical collapse model to study the dynamical state of the supercluster.
Results: In the A2142 supercluster rich groups and clusters lie along an almost straight line forming the 50h-1 Mpc long main body of the supercluster. The A2142 supercluster has a very high density core surrounded by lower-density outskirts. The total estimated mass of the supercluster is Mest = 6.2 × 1015 M⊙. More than a half of groups with at least ten member galaxies in the supercluster lie in the high-density core of the supercluster, centred at the X-ray cluster
Conclusions: A2142 supercluster with collapsing core and straight body, is an unusual object among superclusters. In the course of the future evolution, the supercluster may split into several systems.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- August 2015
- DOI:
- 10.1051/0004-6361/201526399
- arXiv:
- arXiv:1505.07233
- Bibcode:
- 2015A&A...580A..69E
- Keywords:
-
- cosmology: miscellaneous;
- large-scale structure of Universe;
- galaxies: groups: general;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 13 pages, 9 figures, Astronomy and Astrophysics, in press. References updated