Degree Angular Scale Interferometer 3 Year Cosmic Microwave Background Polarization Results

We present the analysis of the complete 3-year data set obtained with theDegree Angular Scale Interferometer (DASI) polarization experiment, operatingfrom the Amundsen-Scott South Pole research station. Additional data obtainedat the end of the 2002 Austral winter and throughout the 2003 season were addedto the data from which the first detection of polarization of the cosmicmicrowave background radiation was reported. The analysis of the combined datasupports, with increased statistical power, all of the conclusions drawn fromthe initial data set. In particular, the detection of E-mode polarization isincreased to 6.3 sigma confidence level, TE cross-polarization is detected at2.9 sigma, and B-mode polarization is consistent with zero, with an upper limitwell below the level of the detected E-mode polarization. The results are inexcellent agreement with the predictions of the cosmological model that hasemerged from CMB temperature measurements. The analysis also demonstrates thatcontamination of the data by known sources of foreground emission isinsignificant.Comment: 13 pages Latex, 10 figures, submitted to Ap