Excitation functions of 74Se(d,xn) 75,74mBr reactions: Comparative evaluation of possible routes for the production of 75Br at a small cyclotron

Abstract

Excitation functions were measured for the first time for 74Se(d,n) 75Br and 74Se(d,2n) 74mBr reactions from threshold to 23 MeV. Use was made of the stacked-foil technique, and thin samples were prepared by electrolytic deposition of 31.4% enriched 74Se on Al-backing. Differential and integral yields of 74mBr and 75Br were calculated from the measured excitation functions. The optimum energy range for the production of 75Br via the 74Se(d,n)-process was found to be E d = 12 → 8 MeV, with 75Br-yield amounting to 509 MBq (13.75 mCi)/μAh and the 74mBr impurity to <I%. A comparative evaluation of the two routes, namely 78Kr(p,α) 75Br and 74Se(d,n) 75Br, suggested for the production of 75Br at a small cyclotron is given. The (d,n) reaction gives higher yield than the (p,α) process and is preferable at cyclotrons with E d ⩾ 10 MeV. In general, at a small cyclotron the achievable batch yields of 75Br via both the processes are limited.