Signature of nonexponential nuclear decay

TL;DR

This paper predicts that nonexponential decay in nuclear fission occurs on attosecond timescales, suggesting that observed decay times may reflect quantum decoherence effects rather than actual decay durations.

Contribution

It introduces a quantum decoherence framework predicting attosecond nonexponential decay times in nuclear fission, explaining discrepancies in experimental measurements.

Findings

Decoherence time of nuclear decay is on the order of attoseconds.

Observed decay times may reflect quantum decoherence rather than true decay durations.

Controversy in experimental results can be explained by nonexponential decay effects.

Abstract

Precision tests of decay law of radioactive nuclei have not so far found any deviation from the exponential decay law at early time, as predicted by quantum mechanics. In this paper, we show that the quantum decoherence time (i.e. the timescale of nonexponential decay) of the quasifission or fission process should be of the order of attosecond considering the atom of the fissioning nucleus as a quantum detector. Hence, the observed decay timescale of the quasifission or fission process of even highly excited (EX greater than 50 MeV) transuranium and uraniumlike complexes should be rather long (of the order of attosecond) in spite of their very fast exponential decay timescale (of the order of zeptosecond) as measured by the nuclear techniques. Recent controversy regarding the observation of very long (of the order of attosecond ) and very short (of the order of zeptosecond ) quasifission or fission timescales for similar systems at similar excitation energies as obtained by direct techniques (crystal blocking, X ray fission fragment) and nuclear techniques could be interpreted as evidence for nonexponential decays in nuclear systems