TL-201 YIELDS AND EXCITATION-FUNCTIONS FOR 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→205Tl and 205Tl(p,5n)201Pb→201Tl nuclear reactions. The yields (Ci g-1cm2/μA-hr) of the parent 201Pb(9.4 hr), as well as the radiocontaminants 200Pb(21.5 hr), 202mPb (3.62 hr), 203Pb(52.1 hr) and 204mPb(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 (CNL). 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 the 205Tl(p,5n)201Pb reactions were measured in the 15-60-MeV energy range. © 1978.