Cross-section measurement of the Tm-169(p,n) reaction for the production of the therapeutic radionuclide Yb-169 and comparison with its reactor-based generation

摘要

The radionuclide Yb-169 (T-1/2 = 32.0 d) is potentially important for internal radiotherapy. It is generally produced using a nuclear reactor. In this work the possibility of its production at a cyclotron was investigated. A detailed determination of the excitation function of the Tm-169(p,n)Yb-169 reaction was done over the proton energy range up to 45 MeV using the stacked-foil technique and high-resolution gamma-ray spectrometry. The integral yield of Yb-169 was calculated. Over the optimum energy range E-P = 16 -> 7 MeV the yield amounts to 1.5 MBq/mu A h and is thus rather low. A comparison of this production route with the established Yb-168(n,gamma) Yb-169 reaction at a nuclear reactor is given. The Yb-169 yield via the reactor route is by several orders of magnitude higher than by the cyclotron method. The latter procedure, however, leads to "no-carrier-added" product. (c) 2005 Elsevier Ltd. All rights reserved.