Rutgers, the State University of New Jersey
Clusters and Cosmology from the Atacama Cosmology Telescope
The Atacama Cosmology Telescope (ACT) is a 6-m diameter telescope with
a sensitive mm-wave band camera custom designed to survey the cosmic
microwave background (CMB) on arcminute angular scales. The camera
observes simultaneously in three bands at frequencies of 148 GHz, 220
GHz, and 270 GHz. One of the goals of the project is to find galaxy
clusters through the Sunyaev-Zel'dovich effect, which arises when hot
electrons in the cluster inverse Compton scatter cold CMB photons.
The SZ effect manifests as a decrement in ACT's low frequency channel,
an increment in its high frequency channel, and a null in the middle
channel. Over the past year the ACT team has pursued an ambitious
program to identify and characterize the ACT clusters and utilize them
to constrain the growth of structure in the Universe. In this
colloquium I will present our current results and describe our plans
for the future.