Internal conversion of nuclear transition in the ${}^{235m}U@C_{60-n}X_n$ molecules and related compounds

TL;DR

This paper investigates how the internal conversion process of the ${}^{235m}U$ nuclear isomer is affected by chemical environment and physical conditions, especially in fullerene molecules, impacting its decay rate.

Contribution

It demonstrates that the decay rate of ${}^{235m}U$ can be significantly altered by chemical and physical surroundings, particularly in fullerene compounds, which is a novel insight.

Findings

Decay rate depends on chemical composition and physical conditions.

Fullerene molecules can significantly modify the decay rate.

Potential applications in controlling nuclear decay processes.

Abstract

The internal conversion of nuclear transition in the ${}^{235}U$ atom is considered. The low-energy $\gamma-$quanta ($E_{\gamma} \approx$ 76.8 $eV$) are emitted during the $E3-$transition from the excited state ($I = (\frac12)^+$) of the ${}^{235}U$ nucleus to its ground state ($I = (\frac72)^-$). The decay rate of this ${}^{235m}U$ isomer ($E \approx 76.8$ $eV$) noticeably depends upon the chemical composition and actual physical conditions (i.e. temperature $T$ and pressure $p$). By varying such a composition and physical conditions one can change the life-time of the ${}^{235m}U$ isomer to relatively large/small values. A specific attention is given to the fullerene molecules containing the central ${}^{235}U$ atom. It is shown that the decay rate $\lambda$ of the ${}^{235m}U$ isomer in the ${}^{235m}U@C_{60-n}X_n$ molecules and related compounds can differ significantly from the values obtained for isolated ${}^{235}U$ atoms. Some applications of this effect are considered.