The Cluster Mass Function from Early SDSS Data: Cosmological Implications
摘要
The mass function of clusters of galaxies is determined from 400 deg^2 of early commissioning imaging data of the Sloan Digital Sky Survey; ~300 clusters in the redshift range z = 0.1 - 0.2 are used. Clusters are selected using two independent selection methods: a Matched Filter and a red-sequence color magnitude technique. The two methods yield consistent results. The cluster mass function is compared with large-scale cosmological simulations. We find a best-fit cluster normalization relation of sigma_8*omega_m^0.6 = 0.33 +- 0.03 (for 0.1 ~< omega_m ~< 0.4), or equivalently sigma_8 = (0.16/omega_m)^0.6. The amplitude of this relation is significantly lower than the previous canonical value, implying that either omega_m is lower than previously expected (omega_m = 0.16 if sigma_8 = 1) or sigma_8 is lower than expected (sigma_8 = 0.7 if omega_m = 0.3). The best-fit mass function parameters are omega_m = 0.19 (+0.08,-0.07) and sigma_8 = 0.9 (+0.3,-0.2). High values of omega_m (>= 0.4) and low sigma_8 (=< 0.6) are excluded at >~ 2 sigma.
引用
@article{arxiv.astro-ph/0205490,
title = {The Cluster Mass Function from Early SDSS Data: Cosmological Implications},
author = {Neta A. Bahcall and Feng Dong and Paul Bode and Rita Kim and James Annis and Timothy A. McKay and Sarah Hansen and James Gunn and Jeremiah P. Ostriker and Marc Postman and Robert C. Nichol and Tomotsugu Goto and Jon Brinkmann and Gillian R. Knapp and Don O. Lamb and Donald P. Schneider and Michael S. Vogeley and Donald G. York},
journal= {arXiv preprint arXiv:astro-ph/0205490},
year = {2009}
}
备注
AASTeX, 25 pages, including 7 figures, accepted for publication in ApJ, vol.585, March 2003