Speaker
Description
The ISAC facility at TRIUMF hosts two high purity germanium detector arrays which allow for world-class gamma-ray spectroscopy experiments: TIGRESS (mainly used for reaction studies) and GRIFFIN (for decay studies). These detectors are typically utilized in radioactive beam experiments, however the finite beamtime available at ISAC results in regular periods of downtime where the detector equipment is operable but remains unused. This downtime could be used to perform high statistics decay spectroscopy of radioactive sources, to investigate rare decay modes and other nuclear structure properties of the isotopes in question. The availability of small medical cyclotrons at TRIUMF allows for local production of sources with short half-lives, that would otherwise only be accessible through implantation or reaction studies using accelerated beams.
We have recently carried out a proof of concept in which a high activity (~ 5 MBq) source of the nuclear isomer $^{93m}$Mo (t1/2 = 6.85 hours) was produced via proton irradiation of a niobium target foil using the TR13 medical cyclotron. This source was then measured using GRIFFIN for several days, in an experiment designed to search for the predicted but as-yet unobserved E6 decay (a rare decay mode in which a gamma ray carries six units of angular momentum) of the isomer. The combination of high source activity (only achievable using local source production) and high detection efficiency of the GRIFFIN array resulted in a dataset with extremely high statistics compared to previously published data. Preliminary results of the data analysis will be shown, and the feasibility of other experiments using local source production will be discussed.
| Email address | ewilliams@triumf.ca |
|---|---|
| Supervisor's Name | Greg Hackman |
| Supervisor's email | hackman@triumf.ca |
| Classification | Isotope production, target, and ion source techniques |
