Neutron Spin Rotation: Data Acquisition and Sensitivity Updates

The previous neutron spin rotation experiments conducted by the NSR Collaboration were able to obtain upper bounds of (2.1+/-8.3(stat.)+2.9/-0.2(sys.)) x10^-7 rad/m for liquid Helium [2] and (2.8+/-4.6(stat.)+/-4.0(sys.))x10^-5 rad/m for g_A² neutron coupling to matter [1]. In addition to new theoretical predictions and target system improvements, the NSR polarimeter has undergone several upgrades in its data acquisition software and instrumentation. These new systems will be used in an upcoming set of runs at the NIST NG-C beam line where significant systematic and statistical error reduction is expected. Details of the data acquisition and instrumentation and projections for statistical and systematic sensitivities will be discussed.

[1] Chris Haddock et al., Phys. Lett. B 783 (2018)

[2] H. E. Swanson et al., Phys. Rev. C 100 (2019)