Speaker
Description
A calibration for polarization responses (i.e. angle and gain) is an important subject for sucess of CMB polarization experiments. We (I and my colleagues) have developed calibration systems using sparse wire grid. Wires in ambient make a blackbody signal which is linearly polarized. Focal plane detectors measure the polarization signal when we set the wires in front of receiver or telescope aparture. The direction of polarization is parallel to the wire derection, and its intensity is proportional to the wire dencity. Thus far, this type calibration has been demonstrated in QUIET, ABS, POLARBEAR, and Simons Aarray experiments. In future, Small Aparture Telescopes in the Simons Observatory will regurally use this type calibrator towards the best systematic error control to date. In this presentation, I will review ideas/systems/experiences for each experiment.
