AMiBA first year observation

ABSTRACT Usingthearrayofseven0.6mantennasinHawaii,wehaveconductedshortobservationsonseveralgalaxyclustersthroughthe Sunyaev-Zeldovich effect at 3mm wavelength in 2007. The observations were done with a resolution of 6O, and wehave chosen the low redshift (z=0.09Ð0.32) massive clusters to optimize detection. Major contamination to the data comesfrom instrumental offset and ground pickup. We will demonstrate the results based on a simple on source - off sourceswitching observing scheme. In addition, the performance of a wideband analog 4-lag correlator was also investigated.Keywords: CMB N galaxy clusters: general N galaxy clusters: individual(A1689, A1995, A2142, A2163, A2261,A2390) N SZ effect 1. INTRODUCTION The power spectrum of the Cosmic Microwave Background (CMB) anisotropy is so far consistent with the standard modelin a sat universe with dark energy. On larger scales, the anisotropy is dominated by the primary CMB, whereas on smallerscales, secondary effects such as the Sunyaev-Zeldovich (SZ) effect from galaxy clusters should deÞne the shape of thepower spectrum. The strength and the distribution of the SZ power spectrum is particularly sensitive to the amplitudeof initial density perturbation, quantiÞed by