Recoil properties of Ta isotopes produced in the interaction of high-energy protons with Bi and U

Thick-target thick-catcher recoil properties were determined for neutron-deficient Ta isotopes produced in the interaction of 0.45- and 11.5-GeV protons with Bi and U. The production mechanism was shown to be a binary mass division process at 0.45 GeV. At 11.5 GeV, either a high-excitation-energy ("deep") spallation process or a fission process from light nuclei is a possible mechanism. The half-life of ${}_{}{}^{179}{}_{}{}^{}\mathrm{Ta}$, measured on two samples over a period of two years, was determined to be 588 ± 10 days.