[Previous] | [Session 58] | [Next]
A.E. Evrard (U. Michigan), Virgo Collaboration
The abundance of distant clusters is a sensitive probe of cosmology. We explore theoretical expectations for distant counts using clusters extracted from deep, light--cone datasets of the Hubble Volume simulations. Two cold, dark matter (CDM) dominated models with flat metric geometries are employed: a \tauCDM model dominated by matter (\Omegam = 1) and a LCDM model dominated by vacuum energy (\Omega\Lambda=0.7, \Omegam = 0.3). Each simulation uses one billion particles in cubes of side lengths 2000/h (\tauCDM) and 3000/h (LCDM) Mpc.
Examining synthetic sky surveys covering \pi steradians which extend to redshift z ~q 1.3, we identify ~ 105 clusters more massive than {1014 h-1 {\rm M}\odot}. Clear differences in the redshift evolution of the population are apparent between the two cosmologies. Guided by gas dynamic simulations of cluster formation, we make predictions for the expected behavior in X-ray and Sunyaev--Zel'dovich counts. The impact on current and future surveys of distant clusters is discussed.
If the author provided an email address or URL for general inquiries, it is a
s follows:
http://www.physics.lsa.umich.edu/hubble-volume