CMB polarimetry with BICEP: instrument characterization, calibration,   and performance
  BICEP is a ground-based millimeter-wave bolometric array designed to target the primordial gravity wave signature on the polarization of the cosmic microwave background (CMB) at degree angular scales. Currently in its third year of operation at the South Pole, BICEP is measuring the CMB polarization with unprecedented sensitivity at 100 and 150 GHz in the cleanest available 2% of the sky, as well as deriving independent constraints on the diffuse polarized foregrounds with select observations on and off the Galactic plane. Instrument calibrations are discussed in the context of rigorous control of systematic errors, and the performance during the first two years of the experiment is reviewed. 
Yuki D. Takahashi, Denis Barkats, John O. Battle, Evan M. Bierman,   James J. Bock, H. Cynthia Chiang, C. Darren Dowell, Eri...