A systematic theoretical investigation of proton-induced nuclear reactions on 169 Tm was performed using the TALYS-2.0 nuclear reaction code for incident proton energies up to 200 MeV. Excitation functions were calculated for the 169 Tm(p, n+ α ) 165 Er, 169 Tm(p, α ) 166 Er, 169 Tm(p, 3 He) 167 Er, 169 Tm(p, t) 167 Tm, 169 Tm(p, n+p) 168 Tm, 169 Tm(p, 4n) 166 Yb, 169 Tm(p, 3n) 167 Yb, 169 Tm(p, 2n) 168 Yb, 169 Tm(p, n) 169 Yb, and 169 Tm(p, γ ) 170 Yb reaction channels using six nuclear level density models (CTM, BFM, GSM, SHFB, SHFB(C), and GHFB). Particular attention was given to the medically important 169 Tm(p, n) 169 Yb reaction for the production of the therapeutic radionuclide 169 Yb. The calculated excitation functions were compared with available experimental data from the EXFOR database and the TENDL-2023 evaluated library. Model performance was assessed through statistical deviation factors ( F , D , and R ), revealing that no single level density model consistently outperformed the others across all reactions and datasets. Phenomenological models generally showed better agreement with TENDL-2023 evaluations, whereas microscopic models provided improved consistency with several experimental measurements. The 169 Tm(p, n) 169 Yb reaction exhibited an optimum energy region around 10 - 15 MeV, with a maximum cross section near 11 MeV. Production characteristics, including activity, production amount, and integral yield, confirmed the feasibility of accelerator-based 169 Yb production. The present results provide valuable nuclear data for reaction channels lacking experimental information and support the development of reliable production routes for 169 Yb in nuclear medicine applications.
Keywords169 Tm(pn) 169 Yb ReactionTherapeutic Radionuclide 169 YbTALYS-2.0Nuclear Level Density ModelsExcitation Function
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