Why measure CMB Polarization?: Why measure CMB Polarization?
Directly measures dynamics in early universe Critical test of the underlying theoretical framework if it’s not there at the predicted level, we’re back to the drawing board. Future: Can triple the number of CMB observables better constraints And, eventually, perhaps, measure the primordial gravity wave and directly test Inflation prediction and energy scale (this is going to be hard!) CMB Polarization: CMB Polarization Simultaneous differencing of 2 polarization states using correlation receivers with HEMT amplifiers New 2002 limit POLAR: Keating et al. astro-ph/0107013; PIQUE: Hedman et al. astro-ph/0204438 Slide8: Generating CMB Polarization Density mode velocities (hot to cold) hotter due to dopler shift Before decoupling: electron ‘sees’ only a local monopole During decoupling: mean free path increases and electron ‘sees’ quadrupole scattered light is polarized E-mode from density modes (scalar fluctuations) has to be there! E & B-mode from gravity waves (tensor) hotter due to dopl
