Thallium-201 yields and excitation functions for the lead radioactivities produced by irradiation of natural thallium with 15-60 MeV protons

Excitation functions, production yields and radionuclidic purities are described for 201Tl production by the 203Tl(p,3n) 201Pb → 201Tl and 205Tl(p,5n)201Pb→201Tl nuclear reactions. The yields (mCi g-1 cm2/μA-hr) of the parent 201Pb(9.4hr), as well as the radiocontaminants 200Pb(21.5hr), sup(202m)Pb(3.62 hr), 203Pb(52.1 hr) and sup(204m)Pb(1.115 hr) were measured by irradiating a stack of thin natural Tl foils with protons from the 76-in isochronous cyclotron at the Crocker Nuclear Laboratory. The 201Tl thick-target yield (mCi/μA hr) was calculated for different target thicknesses and corresponding incident proton energies. The excitation functions for the 203Tl(p,3n)201Pb and 205Tl(p,5n)201Pb reactions were measured in the 15-60-MeV energy range. (author)