Abstract
Phys.Rev.D67:023003,2003 We compute upper limits on CMB cross-polarization by cross-correlating the
PIQUE and Saskatoon experiments. We also discuss theoretical and practical
issues relevant to measuring cross-polarization and illustrate them with
simulations of the upcoming BOOMERanG 2002 experiment. We present a method that
separates all six polarization power spectra (TT, EE, BB, TE, TB, EB) without
any other "leakage" than the familiar EE-BB mixing caused by incomplete sky
coverage. Since E and B get mixed, one might expect leakage between TE and TB,
between EE and EB and between BB and EB - our method eliminates this by
preserving the parity symmetry under which TB and EB are odd and the other four
power spectra are even.
