Using the Fisher matrix formalism, we quantitatively investigate the constraints on a 10 dimensional space of cosmological parameters which may be obtained with future cluster surveys. We explore the dependence of the Ω m constraint on both angular coverage and depth of field. We show that in each case there is a natural cutoff beyond which the constraints on Ω m do not significantly improve. We also investigate the sensitivity of the constraints to changes in our knowledge of the Mass-Temperature (M-T) relation by including its normalization and scatter as two of the parameters in the Fisher matrix.To make our analysis more realistic, we have added, as priors, the Fisher matrices from hypothetical supernova and CMB experiments. We find that X-ray cluster surveys actually help to constrain the M-T relation, and explore the implications of this result.

The coupling of photons and baryons by Thomson scattering in the early universe imprints features in both the Cosmic Microwave Background (CMB) and matter power spectra. The former have been used to constrain a host of cosmological parameters, the latter have the potential to strongly constrain the expansion history of the universe and dark energy. Key to this program is the means to localize the primordial features in observations of galaxy spectra which necessarily involve galaxy bias, non-linear evolution and redshift space distortions. We present calculations, based on mock catalogs produced from high-resolution N-body simulations, which show the range of behaviors we might expect of galaxies in the real universe. We investigate physically motivated fitting forms which include the effects of non-linearity, galaxy bias and redshift space distortions and discuss methods for analysis of upcoming data. In agreement with earlier work, we find that a survey of several Gpc 3 would constrain the sound horizon at z ∼ 1 to about 1%. 4 djschlegel@lbl.gov 5 msw@lanl.gov 6 http://www.sdss.org/

We study the profiles of 75 086 elliptical galaxies from the Sloan Digital Sky Survey (SDSS) at both large (70-700 h −1 70 kpc) and small (∼4 h −1 70 kpc) scales. Weak lensing observations in the outskirts of the halo are combined with measurements of the stellar velocity dispersion in the interior regions of the galaxy for stacked galaxy samples. The weak lensing measurements are well characterized by a Navarro, Frenk and White (NFW) profile. The dynamical mass measurements exceed the extrapolated NFW profile even after the estimated stellar masses are subtracted, providing evidence for the modification of the dark matter profile by the baryons. This excess mass is quantitatively consistent with the predictions of the adiabatic contraction (AC) hypothesis. Our finding suggests that the effects of AC during galaxy formation are stable to subsequent bombardment from major and minor mergers. We explore several theoretical and observational systematics and conclude that they cannot account for the inferred mass excess. The most significant source of systematic error is in the initial mass function (IMF), which would have to increase the stellar mass estimates by a factor of two relative to the Kroupa IMF to fully explain the mass excess without AC. Such an increase could be achieved by switching from a Kroupa to a Salpeter IMF (with cut-off at 0.1 M ), but doing so would cause significant tension with results from SAURON. We demonstrate a connection between the level of contraction of the dark matter halo profile and scatter in the size luminosity relation, which is a projection of the fundamental plane. Whether or not AC is the mechanism supplying the excess mass, models of galaxy formation and evolution must reconcile the observed halo masses from weak lensing with the comparatively large dynamical masses at the half-light radii of the galaxies.

We use a simplified version of the halo model with a power law power spectrum to study scale dependence in galaxy bias at the very large scales relevant to baryon oscillations. In addition to providing a useful pedagogical explanation of the scale dependence of galaxy bias, the model provides an analytic tool for studying how changes in the Halo Occupation Distribution (HOD) impact the scale dependence of galaxy bias on scales between 10 and 1000 Mpc/h, which is useful for interpreting the results of complex N-body simulations. We find that changing the mean number of galaxies per halo of a given mass will change the scale dependence of the bias, but that changing the way the galaxies are distributed within the halo has a smaller effect on the scale dependence of bias at large scales. We use the model to explain the decay in amplitude of the baryon oscillations as k increases, and generalize the model to make predictions about scale dependent galaxy bias when redshift space distortions are introduced.Comment: 13 pages, 2 figures; corrected typos, extended discussion of redshift space distortions, matches published versio

We have created mock Sunyaev-Zel'dovich effect (SZE) surveys of galaxy clusters using high-resolution Nbody simulations. To the pure surveys, we add '' noise '' contributions appropriate to instrument and primary cosmic microwave background anisotropies. Applying various cluster finding strategies to these mock surveys, we generate catalogs that can be compared to the known positions and masses of the clusters in the simulations. We thus show that the completeness and efficiency that can be achieved depend strongly on the frequency coverage, noise, and beam characteristics of the instruments, as well as on the candidate threshold. We study the effects of matched filtering techniques on completeness and bias. We suggest a gentler filtering method than matched filtering in single-frequency analyses. We summarize the complications that arise when analyzing the SZE signal at a single frequency and assess the limitations of such an analysis. Our results suggest that some sophistication is required when searching for '' clusters '' within an SZE map.