We report an improved measurement of the degree-scale cosmic microwave background B-mode angular-power spectrum over 670 square-degree sky area at 150 GHz with POLARBEAR. In the original analysis of the data, errors in the angle measurement of the continuously rotating half-wave plate, a polarization modulator, caused significant data loss. By introducing an angle-correction algorithm, the data volume is increased by a factor of 1.8. We report a new analysis using the larger data set. We find the measured B-mode spectrum is consistent with the ΛCDM model with Galactic dust foregrounds. We estimate the contamination of the foreground by cross-correlating our data and Planck 143, 217, and 353 GHz measurements, where its spectrum is modeled as a power law in angular scale and a modified blackbody in frequency. We place an upper limit on the tensor-to-scalar ratio r < 0.33 at 95% confidence level after marginalizing over the foreground parameters.
@article{arxiv.2203.02495,
title = {Improved upper limit on degree-scale CMB B-mode polarization power from the 670 square-degree POLARBEAR survey},
author = {The POLARBEAR Collaboration and S. Adachi and T. Adkins and M. A. O. Aguilar Faúndez and K. S. Arnold and C. Baccigalupi and D. Barron and S. Chapman and K. Cheung and Y. Chinone and K. T. Crowley and T. Elleflot and J. Errard and G. Fabbian and C. Feng and T. Fujino and N. Galitzki and N. W. Halverson and M. Hasegawa and M. Hazumi and H. Hirose and L. Howe and J. Ito and O. Jeong and D. Kaneko and N. Katayama and B. Keating and T. Kisner and N. Krachmalnicoff and A. Kusaka and A. T. Lee and E. Linder and A. I. Lonappan and L. N. Lowry and F. Matsuda and T. Matsumura and Y. Minami and M. Murata and H. Nishino and Y. Nishinomiya and D. Poletti and C. L. Reichardt and C. Ross and Y. Segawa and P. Siritanasak and R. Stompor and A. Suzuki and O. Tajima and S. Takakura and S. Takatori and D. Tanabe and G. Teply and K. Yamada and Y. Zhou},
journal= {arXiv preprint arXiv:2203.02495},
year = {2022}
}