Transient Joule- and (ac) Josephson-like photon emission in one- and two- nucleon tunneling processes between superfluid nuclei: blackbody and coherent spectral functions

TL;DR

This paper investigates photon emission during nucleon tunneling in superfluid nuclei, revealing distinct spectral and angular features linked to thermal and coherent transfer processes, akin to Joule and Josephson effects.

Contribution

It introduces a novel analysis of gamma-ray spectral functions and angular distributions associated with nucleon tunneling, highlighting the different physics of Joule-like and Josephson-like nuclear processes.

Findings

Blackbody spectral dependence in one-nucleon transfer

Gaussian spectral dependence in two-nucleon transfer

Distinct angular distribution patterns for different processes

Abstract

Effective charged neutrons involved in one- and two- nucleon tunneling processes in heavy ion collisions between superfluid nuclei are expected to emit photons. Although the centroid, width and integrated energy area characterizing the associated gamma-strength functions are rather similar, the corresponding line shapes reflect the thermal equilibrated-like character of the quasiparticle transfer (1n-channel, blackbody spectral functional dependence), and the quantal coherent character of the Cooper pair transfer (2n-channel, Gaussian functional dependence) respectively. The predicted angular distributions, polarizations and analyzing power provide further insight into the profoundly different physics to be found at the basis of what can be considered a transient Joule-like and a (ac) Josephson-like nuclear processes