A method for estimation of isotope yield in a thick target under photonuclear production

A model for analytical description of high-energy Bremsstrahlung radiation and activation of the thick production target is presented. Simple formulas including limited number of testable radiation parameters and the excitation function in the Breit-Wigner form are derived for determining effective cross-section of photonuclear reaction and isotope yield. As an illustration, we consider the 48Ti(γ, p)47Sc, 68Zn(γ, p)67Cu, 100Mo(γ, n)99Mo, 112Sn(γ, p)111In, and 193Ir(γ, n)192Ir reactions that can be used for production of some medical isotopes. It has been shown that the values of the proportionality factor between peak and effective cross-sections for the reactions under study (in the range of target atomic number Z ∼ 20-80) are adjacent for a specified endpoint energy of Bremsstrahlung spectrum in the range of practical interest 40-100 MeV. The obtained data on isotope yield are compared with experimental and simulation results.