We have developed Antenna-coupled transition-edge sensor (TES) arrays for high-sensitivity cosmic microwave background (CMB) observations over a wide range of millimeter-wave bands. BICEP Array is the latest instrument in the BICEP/Keck experiment series, which is designed to search for inflationary B-Modes as low as the tensor-to-scalar ratio r=0.01 in the presence of galactic foregrounds. We will deploy BICEP Array to the South Pole starting at the end of 2019, with detectors spanning 30 to 270 GHz. In this talk, I will describe how we have optimized the low frequency 30/40 GHz detector antennas and packaging for optical efficiency and beam matching between polarization pairs. I will also describe how the uniformly illuminated antennas arrays provides a higher packing density than non-uniform alternatives and will share dual-color detector designs that could further increase detector density. I will finally report our latest measurements for the newly broad-band corrugation design to minimize the beam differential ellipticity between polarization pairs caused by the metal frame of the housing over 30/40 GHz.
|Less than 5 years of experience since completion of Ph.D||N|
|Student (Ph.D., M.Sc. or B.Sc.)||Y|