The Crab Nebula As a Calibrator for Wide-beam Cosmic Microwave Background Polarization Surveys

We analyze the effect of polarized diffuse emission in the calibration of wide-beam millimeter-wave polarimeters, when using the Crab Nebula as a reference source for both polarized brightness and polarization angle. We show that, for CMB polarization experiments aiming at detecting B-mode in a scenario with a tensor to scalar ratio r similar to 0.001, wide (a few degrees in diameter), precise (sigma(Q),sigma(U)similar to 20 mu K(CMB)arcmin), high angular resolution (更多