#
waynehu

## Professor,
Department of Astronomy and Astrophysics

University of Chicago

# High Redshift Cluster Abundance

##
Michael Mortonson, Wayne Hu, & Dragan Huterer

Driver and fitting routines for computing the predicted number of clusters
in a ΛCDM cosmology that agrees with CMB, SN, BAO, H_{0} measurements
(up to 2010) at some specified parameter confidence and the mass which would rule out that cosmology at
some specified sample confidence.

Code:

Inputs:

- cluster mass defined at an overdensity &Delta=200 with respect to the mean
density in units of
*h*^{-1}M_{s}
- cluster redshift
- survey area in which it was found (sq degrees)
- desired confidence level for ΛCDM parameters: e.g. 0.5
for the typical prediction, 0.95 for 95% allowed parameters that maximize the abundance

Outputs:

- mean predicted number above the input mass and redshift
- sample variance exclusion level for finding one such cluster
- mass required for a 95% sample variance exclusion
- local slope of the mass function (for Eddington deboosting)
- all of the above for the 50% parameter (typical) ΛCDM confidence level

Outputs are provided for ΛCDM parameters found by analyzing supernovae
(SN) with MCLS2k2 and with SALT2. MCLS2k2 gives higher predicted abundances and more
conservative exclusion levels. SALT gives a better global fit to ΛCDM models.

### References

[1] ''Simultaneous Falsification of ΛCDM and Quintessence with Massive
Distant Clusters,'' Mortonson, Hu, & Huterer (2010) PRD, submitted,
1011.0004