Enhanced Tritium Production in Irradiated TiD2 from Collisional Fusion in the Solid-State

TL;DR

This paper investigates enhanced tritium production in irradiated TiD2, combining simulations and experiments, and suggests solid-state collision-induced fusion as a potential mechanism for higher neutron yields beyond known nuclear reactions.

Contribution

It provides experimental evidence of increased tritium production in TiD2 and proposes collision-induced fusion in solids as a novel mechanism for nuclear reactions.

Findings

Tritium production matches predictions in thermal neutron spectrum.

Significantly higher tritium yields observed in energetic neutron spectrum.

Suggests additional solid-state fusion mechanisms may be involved.

Abstract

Ongoing research in new nuclear mechanisms hold the potential for beneficial developments in nuclear power cycle designs. Recent reports investigated the possibility of lattice dynamics to influence nuclear processes in metals. Results from Steinetz et al., at the NASA Glenn Research Center indicated that it may be feasible to initiate deuterium deuterium fusion reactions that are enhanced using electron screening to reduce the deuterium deuterium fusion barrier. This article presents tritium production results from both simulations and experiments targeting specific nuclear processes in an effort to identify the source of higher energy neutrons observed in those results. We explore two pathways of tritium generation in TiD2 through this fusion cycle. Tritium production from TiD2 in the University of Missouri Research Reactor, where the neutron spectrum was approximately 90 percent thermal, was within 25 percent of the predicted amount from simulations, and well explained by known nuclear reactions without invoking screening enhanced recoil-induced fusion. Tritium production from TiD2 in the cyclotron vault at MURR, where the neutron spectrum was completely energetic with almost no thermal neutrons, was a factor of 2.9 to 5.1 times higher than predicted from simulations using known nuclear reactions. This indicates the likelihood of an additional mechanism, such as collision-induced fusion in the solid state, increasing the credibility in the results from Steinetz et al.