The Virial Mass Function of Nearby Galaxy Groups and Clusters

Details The Virial Mass Function of Nearby Galaxy Groups and Clusters The Virial Mass Function of Nearby Galaxy Groups and Clusters

Dec 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007aas...211.9606h&link_type=abstract

American Astronomical Society, AAS Meeting #211, #96.06; Bulletin of the American Astronomical Society, Vol. 39, p.901

Mathematics

Logic

Scientific paper

We present a new determination of the cluster mass function in a volume 107 h70-3 Mpc3 using an X-ray-selected sample of systems from the ROSAT All-Sky Survey in the redshift range 0.01 < z < 0.06. We compile optical redshifts for galaxies in these systems from data in the literature and from new data collected with the FAST spectrograph on Mt. Hopkins. We remove foreground and background galaxies (interlopers) using a dynamical maximum-velocity criterion. To estimate the group and cluster masses, we apply the full virial theorem (including the surface pressure term). We verify these results using different interloper removal schemes and mass estimation techniques, including the projected mass estimator. We briefly investigate the σP-LX and M-LX scaling relations and find agreement with previous studies. We then compute the virial mass function of our sample and compare it with that of CIRS (the Cluster Infall Regions in SDSS sample; Rines et al. 2006) and that expected from the WMAP results (Spergel et al. 2007). We discuss the implications of our results, focusing on the low-luminosity systems best probed with this survey. Finally, by comparing our mass function to predictions from various cosmological models, we constrain two cosmological parameters: the density of matter in the universe, Ωm, and the rms amplitude of the density fluctuations on scales of 8 h-1 Mpc, σ8. We find fair agreement between our values for these parameters and the Three-Year WMAP values. This work was supported by a NSF REU grant through the Smithsonian Astrophysical Observatory.

Affiliated with

Also associated with

No associations

Rating

The Virial Mass Function of Nearby Galaxy Groups and Clusters does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Virial Mass Function of Nearby Galaxy Groups and Clusters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Virial Mass Function of Nearby Galaxy Groups and Clusters will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1480203