The Current Status of Precision Superallowed Fermi beta-Decay Measurements at TRIUMF-ISAC

摘要

Recent experimental work at the TRIUMF-ISAC radioactive ion-beam facility in Vancouver Canada, has produced several new results related to precise experimental tests of fundamental symmetries. The nature of these programs range from campaigns using existing setups, to the development of new apparati to further the experimental reach. One of the primary goals has been the investigation of superallowed Fermi beta-decay, and its relation to Standard Model tests of CVC and CKM unitarity. The extraction of experimental beta-decay ft values requires the measurement of three quantities: the half-life, the superallowed branching ratio, and the parent-daughter mass difference. TRIUMF-ISAC has the ability to measure each of these values with very high precision, using a gas-proportional-counter, the 8pi gamma-ray spectrometer, and TITAN, respectively. This report focuses on the recent experimental progress of the superallowed program, as well as highlighting some results from the successful halo-nucleus mass-measurement program at TITAN.