How did the Virgo cluster form?

作者：Sorce Jenny G; Gottloeber Stefan; Hoffman Yehuda; Yepes Gustavo

来源：Monthly Notices of the Royal Astronomical Society, 2016, 460(2): 2015-2024.

DOI：10.1093/mnras/stw1085

• methods: numerical
• techniques: radial velocities
• galaxies: clusters: general
• large-scale structure of Universe

While the Virgo cluster is the nearest galaxy cluster and therefore the best observed one, little is known about its formation history. In this paper, a set of cosmological simulations that resemble the Local Universe is used to shed the first light on this mystery. The initial conditions for these simulations are constrained with galaxy peculiar velocities of the second catalogue of the Cosmicflows project using algorithms developed within the Constrained Local UniversE Simulation project. Boxes of 500 h(-1) Mpc on a side are set to run a series of dark matter only constrained simulations. In each simulation, a unique dark matter halo can be reliably identified as Virgo's counterpart. The properties of these Virgo haloes are in agreement at a 10-20 per cent level with the global properties of the observed Virgo cluster. Their zero-velocity masses agree at 1 sigma with the observational mass estimate. In all the simulations, the matter falls on to the Virgo objects along a preferential direction that corresponds to the observational filament and the slowest direction of collapse. A study of the mass accretion history of the Virgo candidates reveals the most likely formation history of the Virgo cluster, namely a quiet accretion over the last 7 Gyr.

• 出版日期2016-8-1