The decline rate of the production cross-section of superheavy nuclei with $Z=114-117$ at high excitation energies

TL;DR

This paper predicts the production cross sections of superheavy nuclei with Z=114-117 at high excitation energies, highlighting a slower decline in cross sections due to nuclear stability factors, which could aid future synthesis efforts.

Contribution

It provides the first comprehensive predictions of superheavy nuclei production cross sections using a consistent nuclear data approach, revealing unexpected stability at higher excitation energies.

Findings

Cross sections decline slowly with increasing excitation energy.

Fission barriers protect the compound nucleus, enabling neutron evaporation.

Formation probabilities remain promising in 5n-7n channels.

Abstract

The production cross sections of superheavy nuclei with charge numbers $114-117$ are predicted in the $(5-9)n$-evaporation channels of the $^{48}$Ca-induced complete fusion reactions for future experiments. The estimates of synthesis capabilities are based on a uniform and consistent set of input nuclear data provided by the multidimensional macroscopic-microscopic approach. The contributions of various factors to the final production cross section are discussed. As shown, the specific interplay between survival and fusion probabilities unexpectedly leads to a relatively slow decline of the total cross-sections with increasing excitation energy. This effect is supported by a favorable arrangement of fission barriers protecting the compound nucleus against splitting concerning energetic thresholds for the emission of successive neutrons. In particular, the probabilities of the formation of superheavy nuclei in the $5n$-, $6n$-, and in some cases even in $7n$-evaporation channels are still promising. This may offer a new opportunity for the future synthesis of unknown neutron-deficient superheavy isotopes.