# Higgs response and pair condensation energy in superfluid nuclei

## TL;DR

This paper introduces a novel method to characterize pair vibrations in superfluid nuclei by drawing an analogy to the Higgs mode, enabling extraction of pairing energy through response analysis.

## Contribution

The paper proposes a new Higgs-mode inspired approach to analyze pair vibrations and extract pairing energy in nuclei using linear response and sum rules.

## Key findings

- Demonstrated the method on Sn isotopes using QRPA and Skyrme-Hartree-Fock-Bogoliubov models.
- Showed that pairing energy can be obtained from the Higgs response strength and polarizability.
- Validated the approach as a potential tool for pair transfer experiments.

## Abstract

The pairing correlation in nuclei causes a characteristic excitation, known as the pair vibration, which is populated by the pair transfer reactions. Here we introduce a new method of characterizing the pair vibration by employing an analogy to the Higgs mode, which emerges in infinite superconducting/superfluid systems as a collective vibrational mode associated with the amplitude oscillation of the Cooper pair condensate. The idea is formulated by defining a pair-transfer probe, the Higgs operator, and then describing the linear response and the strength function to this probe. We will show that the pair condensation energy in nuclei can be extracted with use of the strength sum and the static polarizability of the Higgs response. In order to demonstrate and validate the method, we perform for Sn isotopes numerical analysis based the quasi-particle random phase approximation to the Skyrme-Hartree-Fock-Bogoliubov model. We discuss a possibility to apply this new scheme to pair transfer experiment.