Commissioning of the RFQ Cooler and Buncher for St. Benedict

Unique insight into the electroweak part of the Standard Model can be found through precision measurements of nuclear beta decays. Non-unitarity of the Cabibo-Kobayashi-Maskawa (CKM) quark mixing matrix would be indicative of physics beyond the Standard Model. Measurements of the beta-neutrino angular correlation parameter for superallowed mixed mirror beta decays can be used to probe the unitarity of this matrix. The Superallowed Transition Beta-Neutrino Decay Ion Coincidence Trap (St. Benedict) is currently under construction at the Nuclear Science Laboratory (NSL) at the University of Notre Dame to improve the accuracy of the V_ud CKM matrix element. St. Benedict is comprised of several beam manipulating devices including a gas catcher, radiofrequency carpet, radiofrequency quadrupole (RFQ) cooler and buncher, and a measurement Paul trap. In order to make measurements at the needed precision, a bunch of ions with a well defined energy and emittance are required. To this effect, an RFQ cooler and buncher, following the design of such a device used for the NSCL EBIT, is currently being commissioned. The off-line commissioning setup consists of a thermionic emission source of potassium ions which sends beam through the RFQ where it is bunched and subsequently measured on a micro channel plate detector. With this system we are able to transport DC beam with 80% efficiency and obtain bunches with an 80 ns full-width-half-maximum. Progress on the off-line commissioning of the radiofrequency cooler and buncher will be presented.