English

Recoil-Order and Radiative Corrections to the aCORN Experiment

Nuclear Experiment 2024-03-04 v2

Abstract

The aCORN experiment measures the electron-antineutrino aa-coefficient in free neutron decay. We update the previous aCORN results to include radiative and recoil corrections to first order, and discuss a key issue in the comparison of results from different aa-coefficient experimental methods when these effects are considered. The corrected combined result is a=0.10779±0.00125(stat)±0.00133(sys)\overline{a} = -0.10779 \pm 0.00125\, ({\rm stat}) \pm 0.00133\, ({\rm sys}), averaged over the full Fermi neutron beta spectrum. The corresponding corrected result for the ratio of weak coupling constants λ=GA/GV\lambda = G_A/G_V is λ=1.2712±0.0061\lambda = -1.2712 \pm 0.0061. This improves agreement with previous aa-coefficient experiments, in particular the 2020 aSPECT result

Keywords

Cite

@article{arxiv.2306.15042,
  title  = {Recoil-Order and Radiative Corrections to the aCORN Experiment},
  author = {F. E. Wietfeldt and W. A. Byron and B. Collett and M. S. Dewey and T. R. Gentile and F. Gluck and M. T. Hassan and G. L. Jones and A. Komives and J. S. Nico and E. J. Stephenson},
  journal= {arXiv preprint arXiv:2306.15042},
  year   = {2024}
}