First Results from the Atacama Cosmology Telescope: SZ Detections of Galaxy Clusters, Jack Hughes (Rutgers University)

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 scales of 1.5 arcmin. The camera observes simultaneously in three bands at frequencies of 145 GHz, 220 GHz, and 280 GHz.  One of the goals of the project is to find galaxy clusters through the Sunyaev-Zeldovich effect, which arises when hot electrons in the cluster inverse Compton scatter cold CMB photons. The SZ effect is manifest as a decrement in ACT's low frequency channel, an increment in its high frequency channel and a null in the middle channel.  In this seminar I will present results on clusters detected by ACT and discuss our on-going multiwavelength follow-up studies of the ACT cluster sample.