EVIDENCE FOR THE FORMATION OF LONG-LIVED Bi208 BY THE (n, 2n) REACTION ON BISMUTH

Abstract

Long-lived Bi²⁰⁸ has been observed through its decay by electron capture to the first excited state of Pb²⁰⁸ at 2.61 Mev. It has been produced by the (n, 2n) reaction on Bi²⁰⁹ in the NRX reactor. The half-life of Bi²⁰⁸ has been estimated to be 3 × 10⁴ years, with an uncertainty of a factor of about 2.