Absence of a self-induced decay effect in 198Au

TL;DR

This study conducted precise measurements of the half-life of 198Au in different shapes to test for a hypothesized self-induced decay effect, finding no evidence supporting its existence.

Contribution

The paper provides an improved experimental test for the self-induced decay effect in 198Au by comparing half-lives in different geometries with increased activity and surface/volume ratios.

Findings

No significant difference in half-lives between sphere and wire

Results are compatible with no self-induced decay effect

Enhanced experimental setup increased sensitivity

Abstract

We report the results of an improved experiment aimed at determining whether the half-life ($T_{1/2}$) of $^{198}$Au depends on the shape of the source. In this experiment, the half-lives of a gold sphere and a thin gold wire were measured after each had been irradiated in the NIST Center for Neutron Research. In comparison to an earlier version of this experiment, both the specific activities of the samples and their relative surface/volume ratios have been increased, leading to an improved test for the hypothesized self-induced decay (SID) effect. We find T_1/2(sphere)/T_1/2(wire) = 0.9993+/-0.0002, which is compatible with no SID effect.