Abstract
We report on a new measurement of the neutron -asymmetry parameter with the instrument Perkeo II. The main enhancements are the high neutron polarization of from a novel arrangement of supermirror polarizers and reduced background from improvements in beam line and shielding. The leading corrections were thus reduced by a factor of 4, pushing them below the level of statistical error and resulting in a significant reduction of systematic uncertainty compared to our previous experiments. We derive the -asymmetry parameter and the ratio of the axial vector to the vector coupling constant .
- Received 13 April 2012
DOI:https://doi.org/10.1103/PhysRevLett.110.172502
© 2013 American Physical Society