Development of TES Bolometer Camera for ASTE Telescope: II. Performance of Detector Arrays

We are developing transition edge sensor (TES) bolometer arrays for a new multicolor millimeter-submillimeter camera for the Atacama Submillimeter Telescope Experiment located at an altitude of 4860 m in the Atacama desert. Our goal is to sensitive multi-color observations for estimating the photometric redshift of dusty star-forming distant galaxies and for precise measurements of properties of galaxy clusters through Sunyaev-Zel'dovich effect. We will have three bands with center wavelengths of 1.1, 0.85, and 0.45 mm, respectively. As the first year of the development program, detector arrays which consist of 169 and 271 TESs designed for observations in 1.1 and 0.85 mm bands are fabricated. Detectors are designed to meet requirements set by the high optical loadings and the need for a high loop gain to enable high-speed scanning. The TES could be successfully brought into the transition as deep as 50% of the normal resistance and loop gain of
$\sim$
40 were achieved. Although other basic parameters of the TES were also in agreement with the designed value, current noise of the TES showed an unexpected rise when the TES is brought into the transition.