We report the first precise measurement of a β-recoil correlation from a radioactive noble gas (6He) confined via a magneto-optical trap. The measurement is motivated by the search for exotic tensor-type contributions to the charged weak current. Interpreted as tensor currents with right-handed neutrinos, the measurements yield: ∣CT/CA∣2≤0.022 (90\% C.L.). On the other hand, for left-handed neutrinos the limits are 0.007<CT/CA<0.111~(90\%\ C.L.). The sensitivity of the present measurement is mainly limited by experimental uncertainties in determining the time response properties and the distance between the atom cloud and the micro-channel plate used for recoil ion detection.
@article{arxiv.2206.00742,
title = {$\beta$-nuclear-recoil correlation from $^6$He decay in a laser trap},
author = {P. Müller and Y. Bagdasarova and R. Hong and A. Leredde and K. G. Bailey and X. Fléchard and A. García and B. Graner and A. Knecht and O. Naviliat-Cuncic and T. P. O'Connor and M. G. Sternberg and D. W. Storm and H. E. Swanson and F. Wauters and D. W. Zumwalt},
journal= {arXiv preprint arXiv:2206.00742},
year = {2022}
}