Positron and gamma-ray intensities in the decay of Ti-45

摘要

To evaluate the PET-imaging properties of the promising positron emitter Ti-45, its beta(+)- and gamma-ray intensities were measured. Use of the cation-exchange resin DOWEX 50Wx8 (H+-form) enabled the isolation of radiochemically pure, no-carrier-added Ti-45 from "bulk" scandium after proton bombardment. Thin, no-carrier-added Ti-45 sampleswere prepared. The combination of gamma-ray and X-ray spectrometry with gamma gamma-coincidence counting allowed for the first time the experimental determination of the positron intensity as (85.67 +/- 2.23)% and the absolute intensity of the 720.22 keV gamma-ray as (0.1171 +/- 0.0057)%.