Beyond mean-field calculation for pairing correlation

TL;DR

This paper applies a symmetry-conserving energy density functional method with Skyrme interaction to improve pairing correlation calculations, especially in magic nuclei, by restoring particle number symmetry and enhancing pairing gaps.

Contribution

It extends the symmetry-conserving approach to include density-dependent terms and performs systematic studies on Kr and Sn isotopes, showing improved pairing predictions.

Findings

Non-zero pairing in magic nuclei achieved

Global enhancement of pairing gaps observed

Highlights importance of readjusting pairing interaction strength

Abstract

The recently proposed Symmetry-Conserving Energy Density Functional approach [G. Hupin, D. Lacroix and M. Bender, Phys. Rev. C84, 014309 (2011)] is applied to perform Variation After Projection onto good particle number using Skyrme interaction, including density dependent terms. We present a systematic study of the Kr and Sn isotopic chains. This approach leads to non-zero pairing in magic nuclei and a global enhancement of the pairing gap compared to the original theory that breaks the particle number symmetry. The need to consistently readjust the pairing effective interaction strength is discussed.