Experimental and Semi-Empirical Branching Fractions of the 3s(2)3p(2)-3s3p(3) J=2 Transition Array in P II

TL;DR

This paper uses a semi-empirical approach to analyze the branching fractions of a specific transition array in P II, combining theoretical modeling with experimental data to understand atomic transition behaviors.

Contribution

It introduces a semi-empirical method fitting parameters to experimental energy levels to predict transition branching fractions in P II, supporting LS-coupling approximations.

Findings

Results align closely with LS-coupling predictions.

Experimental branching ratios are compared with theoretical predictions.

Supports hypothesis on transition array behaviors in low Z atoms.

Abstract

A semi-empirical method is used to characterize the 3s(2)3p(2)-3s3p(3) J=2 transition array in P II. In this method, Slater, spin-orbit, and radial parameters are fitted to experimental energy levels in order to obtain a description of the array in terms of LS-coupling basis vectors. The various IC and CI amplitudes resulting from this model are then used to predict the branching fractions of transitions within the array. Results close to LS-coupling values are presented, and these are compared to branching ratios measured using beam-foil spectroscopy at the THIA laboratory. The work provides support for the hypothesis of Dr. Curtis that transition arrays with little upper state IC but significant upper state CI in atoms of low Z exhibit branching fractions close to LS-coupled values, although the data are inconclusive in this respect.