The Superallowed Transition Beta-Neutrino Decay Ion Coincidence Trap (St. Benedict) is currently under construction at the Nuclear Science Laboratory (NSL) of the University of Notre Dame. It aims to measure the beta-neutrino angular correlation parameter for superallowed mixed mirror beta decay transitions. Measurements of this kind offer unique insight into the electroweak part of the Standard Model through tests of unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. St. Benedict is comprised of several beam-manipulating components including a radio frequency quadrupole (RFQ) ion guide. This ion guide features an off-line source at 90∘ to the beam path for testing and calibration of downstream components once St. Benedict is online. Off-line commissioning of the ion guide demonstrated a transport efficiency greater than 95% for ions coming from the upstream RF carpet chamber. When taking ions from the 90∘ off-line source a lower efficiency of 60% was obtained.
@article{arxiv.2603.10037,
title = {Off-line Commissioning of the St. Benedict Radio Frequency Quadrupole Ion Guide},
author = {R. Zite and M. Brodeur and O. Bruce and D. Gan and P. D. O'Malley and W. S. Porter and F. Rivero},
journal= {arXiv preprint arXiv:2603.10037},
year = {2026}
}