Improved upper limit on degree-scale CMB B-mode polarization power from
  the 670 square-degree POLARBEAR survey
  We report an improved measurement of the degree-scale CMB $B$-mode angular
power spectrum over 670 square-degree sky area 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 $\Lambda$CDM
model with Galactic foregrounds. We place an upper limit on the
tensor-to-scalar ratio $r$ < 0.33 at 95% confidence level.
