Article
Limits on Tensor Coupling from Neutron β Decay
Physical Review C
(2013)
Abstract
Limits on the tensor couplings generating a Fierz interference term b in mixed Gamow-Teller Fermi decays can be derived by combining data from measurements of angular correlation parameters in neutron decay, the neutron lifetime, and GV=GFVud as extracted from measurements of the Ftvalues from the 0+→0+ superallowed decay data set. These limits are derived by comparing the neutron β-decay rate as predicted in the standard model with the measured decay rate while allowing for the existence of beyond the standard model (BSM) couplings. We analyze limits derived from the electron-neutrino asymmetry a, or the beta asymmetry A, finding that the most stringent limits for CT/CA under the assumption of no right-handed neutrinos is −0.0026<CT/CA<0.0024 (95% C.L.) for the two most recent values of A. The derived limits on scalar and tensor couplings have the useful property that they are independent of BSM extensions with vector or axial-vector symmetry to first order.
Keywords
- Limits,
- tensor coupling,
- β decay
Publication Date
October 16, 2013
DOI
10.1103/PhysRevC.92.069902
Publisher Statement
©2013 American Physical Society. Authors have the nonexclusive right to post the APS-prepared version of the article to an institutional repository. This document was originally published in Physical Review C.
Citation Information
Robert W. Pattie, Kevin P. Hickerson and Andrew R. Young. "Limits on Tensor Coupling from Neutron β Decay" Physical Review C Vol. 92 (2013) p. 069902 ISSN: 2469-9985 Available at: http://works.bepress.com/robert-pattie/28/