2022/07/11 by C. Miller, Miller, Caleb
Chemistry · Engineering · Physics and Astronomy · #Advanced NMR Techniques and Applications #Atomic and Subatomic Physics Research #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Particle Accelerators and Free-Electron Lasers
paper · pdf · doi:10.48550/arxiv.2207.05563
openalex publication_date 2022/07/11 · openalex created_date 2022/07/15 · openalex updated_date 2026/07/28
The BABAR collaboration has demonstrated the first application of the new Tau Polarimetry technique. This polarimetry technique exploits the kinematic coupling of τ decay products to the spin states of the τ and initial state electron, to precisely determine the average beam polarization in an e+e- collider. The Tau Polarimetry technique is expected to be used at Belle II following an upgrade to a polarized electron beam, where the precision with which the average beam polarization is known is expected to be the dominant systematic uncertainty in proposed future measurements which require polarized beams. Applying Tau Polarimetry, BABAR has preliminarily measured the PEP-II average beam polarization to be ⟨ P⟩=-0.0010±0.0036_\textrmstat±0.0030_\textrmsys.