Development of direct temperature measurements of ISAC and ARIEL targets at TRIUMF

To improve the thermal modelling of high power isotope separation on-line (ISOL) targets at TRIUMF, an optical technique is being developed that allows for direct off-line and on-line temperature measurements of targets for radioactive isotope production. In this setup the light coming from a hot target through the ionizer opening is collected via a set of optics and coupled into a spectrometer. Thus, from the emission spectrum and Planck’s law, the target temperature can be deduced. Tantalum targets were heated to high temperatures and preliminary temperature measurements confirm the correlation between the spectrum of the radiation emitted from the target and the currents used to resistively heat the targets. The final goal is to apply this technique to on-line targets and correlate the isotope releases with the target temperatures for a better understanding of the diffusion and effusion processes happening in the target and for optimizing the delivery of short-lived species.