Recent studies on the nuclear chemistry of technetium

Abstract

The present status of the nuclear chemistry of technetium and its applications are reviewed. Recent re-evaluations have given longer half-lives for Tc-97 and Tc-98 than those previously found. Nuclear reactions useful in the radioisotope production of technetium are described, emphasizing, in particular, positron-emmitting Tc-94m and Tc-96/Re-183 among the multitracers produced by heavy ion bombardment of gold. Understanding Tc-99 isomer excitation and de-excitation processes is essential to deriving a nuclear model which includes the nucleus-outer electron interaction. The nuclear synthesis of technetium in stars and the shortening of the half-life of Tc-99 with increasing temperature are presented. The 'Molecular rocket' and shock wave phenomena induced by nuclear reactions are further up-to-date subjects to which attention is directed. The results concerned with technetium are summarized and discussed.