Tensor interaction constraints from beta decay recoil spin asymmetry of trapped atoms
Abstract
We have measured the angular distribution of recoiling daughter nuclei emitted from the Gamow-Teller decay of spin-polarized Rb. The asymmetry of this distribution vanishes to lowest order in the Standard Model (SM) in pure Gamow-Teller decays, producing an observable very sensitive to new interactions. We measure the non-SM contribution to the asymmetry to be = 0.015 0.029 (stat) 0.019 (syst), consistent with the SM prediction. We constrain higher-order SM corrections using the measured momentum dependence of the asymmetry, and their remaining uncertainty dominates the systematic error. Future progress in determining the weak magnetism term theoretically or experimentally would reduce the final errors. We describe the resulting constraints on fundamental 4-Fermi tensor interactions.
Keywords
Cite
@article{arxiv.0811.0052,
title = {Tensor interaction constraints from beta decay recoil spin asymmetry of trapped atoms},
author = {J. R. A. Pitcairn and D. Roberge and A. Gorelov and D. Ashery and O. Aviv and J. A. Behr and P. G. Bricault and M. Dombsky and J. D. Holt and K. P. Jackson and B. Lee and M. R. Pearson and A. Gaudin and B. Dej and C. Höhr and G. Gwinner and D. Melconian},
journal= {arXiv preprint arXiv:0811.0052},
year = {2009}
}
Comments
11 pages, 13 figures; v2 published in Phys. Rev. C, with referee clarifications and figures improved for black-and-white