Empirical predictions of yrast energies in even-even nuclei

TL;DR

This paper presents an empirical formula to predict the lowest excitation energies (yrast energies) of even-even nuclei across the periodic table, based on mass number and valence nucleon numbers, with comprehensive data and comparisons.

Contribution

It introduces a simple empirical formula for yrast energies in even-even nuclei, providing a complete tabulation and encouraging further investigation into its underlying physics.

Findings

The empirical formula accurately predicts yrast energies across the periodic table.

Comparison with measured data shows good agreement for natural and unnatural parity states.

The study offers a basis for understanding the relationship between nuclear structure and excitation energies.

Abstract

The lowest excitation energies of the given multipole J^pi state (the J^pi yrast energies) are given for even-even nuclei throughout the entire periodic table. The yrast energies were calculated using the recently proposed empirical formula that depends only on the mass number A, and the valence nucleon numbers Np and Nn. We provide a complete tabulation and plots of the yrast energies calculated using the empirical formula together with the ones measured for the natural parity states up to 10+ and for the unnatural parity states up to 10^+ with the hope of encouraging active study on the possible origin of the relationship between the yrast energies, as revealed by the empirical formula.