Artificial Radioactivity of Tantalum

Abstract

Radioactivity has been induced in tantalum by slow neutrons, fast neutrons, and fast deuterons. (1) Slow neutron capture leads to ${\mathrm{Ta}}^{182}$ with a lifetime of 97 days. (2) Fast neutron bombardment excites, in addition, an 8.2 hour period with the emission of electrons, $K$ radiation of Ta, and $\gamma$-rays. The process responsible for these effects is probably the capture of one neutron with the ejection of two neutrons. The product nucleus, ${\mathrm{Ta}}^{180}$, goes over to ${\mathrm{Hf}}^{180}$ largely by $K$ electron capture; in this process either $\gamma$-rays are emitted or by their internal conversion extranuclear electrons ejected. (3) Deuteron bombardment of tantalum leads to a decay curve affected to such an extent by impurities that the tantalum activity can not be observed clearly.