Nuclear Glory Phenomenon

TL;DR

This paper provides an analytical explanation for the nuclear glory effect, revealing a characteristic angular dependence of the production cross section near the backward direction, supported by qualitative agreement with experimental data.

Contribution

It introduces a small phase space method to explain the nuclear glory phenomenon and proves the angular dependence for multiple interaction processes in nuclear scattering.

Findings

Cross section behaves as 1/√(π - θ) near backward angles.

Qualitative agreement with experimental data.

Potential crater-like angular distribution near θ=π.

Abstract

Analytical explanation of the nuclear glory effect, which is similar to the known optical (atmospheric) glory phenomenon, is presented. It is based on the small phase space method for the multiple interaction processes probability estimates and leads to the characteristic angular dependence of the production cross section $d\sigma \sim 1/ \sqrt {\pi - \theta}$ in the vicinity of the strictly backward direction, for any number of interactions $N\geq 3$, either elastic or inelastic. Rigorous proof of this effect is given for the case of the optimal kinematics, as well as for arbitrary polar scattering angles in the case of the light particle rescattering, but the arguments in favor of the backward azimuthal (axial) focusing are quite general and hold for any kind of the multiple interaction processes. Such behaviour of the cross section near the backward direction agrees qualitatively with available data. In the small interval of final angles including the value $\theta =\pi$ the angular dependence of the cumulative particle production cross section can have the crater-like (or funnel-like) form. Further studies including, probably, certain numerical calculations, are necessary to clear up this point.