AMiBA Observations, Data Analysis and Results for Sunyaev-Zel'dovich Effects

TL;DR

This paper reports on the first-year results of AMiBA, an interferometric experiment measuring the Sunyaev-Zel'dovich effects in galaxy clusters, demonstrating successful observations and data analysis techniques at 3 mm wavelength.

Contribution

It introduces AMiBA's first-year observational results, calibration methods, and data analysis formalism for studying the Sunyaev-Zel'dovich effects in galaxy clusters.

Findings

Detected SZE in six galaxy clusters at redshifts 0.091 to 0.322

Calibrated AMiBA using planets and quasars

Presented images and profiles of galaxy clusters

Abstract

We present observations, analysis and results for the first-year operation of AMiBA, an interferometric experiment designed to study cosmology via the measurement of Cosmic Microwave Background (CMB). AMiBA is the first CMB interferometer operating at 3 mm to have reported successful results, currently with seven close-packed antennas of 60-cm diameter giving a synthesized resolution of around 6'. During 2007 AMiBA detected the Sunyaev-Zel'dovich effects (SZE) of six galaxy clusters at redshift 0.091 <= z <= 0.322. An observing strategy with on-off-source switching is used to minimize the effects from electronic offset and ground pickup. Planets were used to test the observational capability of AMiBA and to calibrate the conversion from correlator time-lag data to visibilities. The detailed formalism for data analysis is given. We summarize our early tests including observations of planets and quasars, and present images, visibility profiles, the estimated central coordinates, sizes, and SZE amplitudes of the galaxy clusters. Science results are summarized. We also discuss possible systematic effects in the results.