Enhanced orbital electron-capture nuclear decay rate in compact medium

TL;DR

This study demonstrates that spatial confinement in small lattices enhances the orbital electron-capture decay rates of certain radioactive isotopes by increasing electron density at the nucleus.

Contribution

It provides experimental evidence that lattice size influences electron-capture decay rates, highlighting the role of spatial confinement in nuclear decay processes.

Findings

Electron capture rates increased by about 1% in Au lattice.

Decay rate increase observed for 109In and 110Sn isotopes.

Results support the theory that confinement affects nuclear decay.

Abstract

The eigenstate energies of an atom increase under spatial confinement and this effect should also increase the electron density of the orbital electrons at the nucleus thus increasing the decay rate of an electron-capturing radioactive nucleus. We have observed that the orbital electron capture rates of 109In and 110Sn increased by (1.00+-0.17)% and (0.48+-0.25)% respectively when implanted in the small Au lattice versus large Pb lattice. These results have been understood because of the higher compression experienced by the large radioactive atoms due to the spatial confinement in the smaller Au lattice.