Gordon Squires		Berkeley
Title: Probing the 3D Galaxy Cluster Structure with SZ, Gravitational
Lensing and X-ray Observations


Abstract:

We are entering a new epoch in rich cluster studies, with the imminent
availability of high signal-to-noise, and high resolution images at
X-ray, radio, and optical wavelengths which provide maps of the
projected X-ray emissivity, the SZ decrement, the cluster galaxy
distribution, and, via gravitational lensing, the projected total mass
distribution. I discuss a general method of deprojecting 2D images to
reconstruct the 3D structure of the projected object, assuming axial
symmetry. The combination of cluster observations at multiple
wavelengths allows a determination of symmetry axis angle, which is in
general unknown from any single observation. However, I show how that
even a single image contains sufficient information for a determination
of the 3D mass profile, using only the assumption of axial
symmetry. Furthermore, I discuss how the combination of SZ measurements
from interferometers (such as BIMA, OVRO) and weak gravitational lensing
observations provide an unbiased, non-parametric determination of the
cluster baryon fraction.  I will show the feasibility of the method as
tested against analytic cluster models, and numerical simulations.
Finally, time permitting, I will discuss an ongoing weak lensing cluster
survey of high-z (z>0.6) X-ray selected clusters, with the goal of
determining the cluster mass function and correlating mass and X-ray
properties in distant clusters.