First season results from QUIET
Næss, Sigurd (Intitute of theoretical astrophysics, University of Oslo)

Inflationary cosmology predicts the excitation of gravitational waves during inflation, and these will leave a unique signature in the divergence-free part of the CMB polarization (B-modes). The Q/U Imaging ExperimenT (QUIET) is a coherent polarimeter experiment observing the CMB polarization at 43 GHz and 90 GHz in four 250 square degree low-foreground patches on the sky, with overlaps with POLARBEAR and ABS. The analysis of the 43 GHz data was recently completed, measuring the E- and B-mode power spectra in the multipole moment range l = 25-475. We confirm BICEP\'s detection of the first E-mode acoustic peak, while the B-mode spectrum is consistent with zero, giving a tensor-to-scalar ratio of r = 0.35 (+1.06 -0.87), with the lowest level of systematic contamination in the B-mode power so far reported. The 90 GHz data analysis is currently under way, and will significantly improve on the 43 GHz limits.