Parity violation constraints using 2006-2007 QUaD CMB polarization spectra

Authors :: QUaD Collaboration
Wu, E. Y. S.
Ade, P.
Bock, J.
Bowden, M.
Brown, M. L.
Cahill, G.
Castro, P. G.
Church, S.
Culverhouse, T.
Friedman, R.
Ganga, K.
Gear, W. K.
Gupta, S.
Hinderks, J.
Kovac, J.
Lange, A. E.
Leitch, E.
Melhuish, S. J.
Memari, Y.
Murphy, J. A.
Orlando, A.
Piccirillo, L.
Pryke, C.
Rajguru, N.
Rusholme, B.
Schwarz, R.
O'Sullivan, C.
Taylor, A. N.
Thompson, K. L.
Turner, A. H.
Zemcov, M.
Source :: Phys.Rev.Lett.102:161302,2009
Publication Year :: 2008
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 CMB photons. We measure the rotation angle due to such a possible "cosmological birefringence" to be 0.55 deg. +/- 0.82 deg. (random) +/- 0.5 deg. (systematic) using QUaD's 100 and 150 GHz TB and EB spectra over the multipole range 200 < l < 2000, consistent with null, and constrain Lorentz violating interactions to < 2^-43 GeV (68% confidence limit). This is the best constraint to date on electrodynamic parity violation on cosmological scales.<br />Comment: 4 pages, 2 figures, accepted to Physical Review Letters. Improved method, updated result and clarified language