Abstract : The muon decay parameter ξ'' has been determined in a measurement of the longitudinal polarization of positrons emitted from polarized and depolarized muons. The result, ξ''=0.981±0.045stat±0.003syst, is consistent with the Standard Model prediction of unity, and provides an order of magnitude improvement in the relative precision of this parameter. This value sets new constraints on exotic couplings beyond the dominant V−A description of the leptonic weak interaction.
http://hal.in2p3.fr/in2p3-01090724
Contributor : Sandrine Guesnon <>
Submitted on : Thursday, December 4, 2014 - 9:43:23 AM Last modification on : Wednesday, January 6, 2021 - 6:44:02 PM
R. Prieels, O. Naviliat-Cuncic, P. Knowles, P. van Hove, X. Morelle, et al.. Measurement of the parameter xi" in polarized muon decay and Implications on exotic couplings of the leptonic weak interaction. Physical Review D, American Physical Society, 2014, 90, pp.112003. ⟨10.1103/PhysRevD.90.112003⟩. ⟨in2p3-01090724⟩