Nuclear data for production of ⁸⁸Y, ¹⁴⁰Nd, ¹⁵³Sm and ¹⁶⁹Yb via novel routes

The possibilities of production of the therapy-related radionuclides ¹⁴⁰Nd, ¹⁵³Sm and ¹⁶⁹Yb, and of ⁸⁸Y, in no-carrier-added form were investigated. For ⁸⁸Y production the nuclear processes ^natSr(p,xn)⁸⁸Y and ^natRb(α, xn)⁸⁸Y over the energy ranges E_p = 14→9 MeV and E_α = 18→12 MeV, respectively, can be utilised, although the former reaction is superior, both in terms of yield and radionuclidic purity. For ¹⁴⁰Nd production the reactions ¹⁴¹Pr(p, 2n)¹⁴⁰Nd and ^natCe(³He, xn)¹⁴⁰Nd were investigated in detail. The optimum energy ranges are E_p = 30→15 MeV and E_³He = 35→ 20 MeV, respectively. Both processes yield high-purity ¹⁴⁰Nd. The former reaction, however, leads to a product yield about 17 times higher than the latter reaction, and is therefore to be preferred. In the case of ¹⁵³Sm, investigations were done on the ¹⁵³Eu(n,p)¹⁵³Sm reaction with 14 MeV d(Be) neutrons as well as on the ¹⁵⁰Nd(α, n)¹⁵³Sm reaction. The yield of the (n,p) reaction is very low, but the (α, n) reaction over the energy range E_α = 25→15 MeV offers a good potential for production of no-carrier-added ¹⁵³Sm in quantities sufficient for therapeutic applications. Also for the radionuclide ¹⁶⁹Yb a novel route, viz.¹⁶⁹Tm(p,n)¹⁶⁹Yb reaction, was investigated. A critical comparison of this route with the commonly used (n, γ) route, however, showed that, due to the much higher cost involved, the (p,n) process should be utilised only when there is a real need of the high specific radioactivity product.