Neutron Spin Rotation: Theoretical Predictions and Experimental Updates

The NSR Collaboration has performed experiments using slow neutron polarimetry to test parity violation in the hadronic weak interaction (HWI) and to search for exotic interactions in beyond-the-Standard Model physics. Updated theoretical predictions suggesting a new upper bound for the neutron rotary power in liquid ⁴He will be compared with the previous measurement of slow neutron spin rotation due to PV in HWI^[1]. We will also discuss theoretical motivations for an improved NSR search for an exotic axial vector interaction via light boson exchange^[2] and compare to bounds on exotic coupling constants measured using other experimental methods. Ongoing updates to both target systems of the polarimeter will be discussed.

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

[2] C. Haddock et al., Phys. Lett. B 783 (2018)