Evaluation of the cross section data for cyclotron production of medical radionuclides 201Pb→201Tl and 203Pb

Lead Isotopes can be effectively used in nuclear medicine, ²⁰³Pb forms a theranostic pair with ²¹²Pb whereas ²⁰¹Pb→ ²⁰¹Tl, facilitate the production of ²⁰¹Tl via the generator system. The aim of this work was to achieve the high purity production of ²⁰³Pb and ²⁰¹Tl via a cyclotron. To achieve this, several charged particle induced reactions namely ²⁰⁵Tl(p,3n)²⁰³Pb, ²⁰⁵Tl(d,4n)²⁰³Pb, ²⁰⁵Tl(p,5n)²⁰¹Pb→²⁰¹Tl, ²⁰⁵Tl(d,6n)²⁰¹Pb→²⁰¹Tl, ²⁰³Tl(p,3n)²⁰¹Pb→²⁰¹Tl, and ²⁰³Tl(d,4n)²⁰¹Pb→²⁰¹Tl were evaluated. First the consistency and reliability of the experimental data were ensured by using established nuclear model codes like TALYS 1.9 and EMPIRE 3.2. A robust methodology, based on experimental data and theoretical nuclear models, was used to generate the recommended cross sections for each production route and associated radioisotopic impurities. The thick target yields were calculated for each production route and its corresponding impurity reaction by utilizing the recommended/reference data. Following a thorough analysis and comparison of the evaluated production routes, it was concluded that the most promising options are ²⁰⁵Tl(d,4n)²⁰³Pb and ²⁰³Tl(p,3n)²⁰¹Pb→²⁰¹Tl. Their optimum conditions were determined as E_d = 30 → 21 MeV and Ep = 30 → 21 MeV with integral yields of 568.9 MBq/μAh and 1223.5 MBq/μAh respectively.