Parity Violation Constraints Using Cosmic Microwave Background Polarization Spectra from 2006 and 2007 Observations by the QUaD Polarimeter

Abstract

We constrain parity-violating interactions to the surface of last scattering using spectra from the QUaD experiment’s second and third seasons of observations by searching for a possible systematic rotation of the polarization directions of cosmic microwave background photons. We measure the rotation angle due to such a possible ‘‘cosmological birefringence’’ to be $0.55^{\circ} \pm 0.82^{\circ}$ (random) $\pm 0.5^{\circ}$ (systematic) using QUaD’s 100 and 150 GHz temperature-curl and gradient-curl spectra over the spectra over the multipole range 200 <$\ell$< 2000, consistent with null, and constrain Lorentz-violating interactions to <2 $\times$ 10$^ {-43}$ GeV (68% confidence limit). This is the best constraint to date on electrodynamic parity violation on cosmological scales.Astronom