Toward a Unified Description of Isoscalar Giant Monopole Resonances in a Self-Consistent Quasiparticle-Vibration Coupling Approach

Abstract

The nuclear incompressibility is a key parameter of the nuclear Equation of State (EoS) that can be extracted from the measurements of the so-called "breathing mode" of finite nuclei. The most serious discrepancy so far is between values extracted from Pb and Sn, that has provoked the longstanding question "Why is tin so soft?". To solve this puzzle, a fully self-consistent Quasiparticle Random-Phase Approximation (QRPA) plus Quasiparticle-Vibration Coupling (QPVC) approach based on Skyrme-Hartree-Fock-Bogoliubov is developed. We show that the many-body correlations introduced by QPVC, which shift the ISGMR energy in Sn isotopes by about 0.4 MeV more than the energy in 208 Pb, play a crucial role in providing a unified description of the ISGMR in Sn and Pb isotopes. The best description of the experimental strength functions is given by SV-K226 and KDE0, which are characterized by incompressibility values K ∞ = 226 MeV and 229 MeV, respectively, at mean field level.

Ab initio description of monopole resonances in light- and medium-mass nuclei

“…the centroid and the dispersion obtained according to Eqs. ( 18) and (19), respectively. Results are displayed in Fig.…”

“…At the same time, beyond-RPA calculations such as self-consistent-RPA (SCRPA) (see Ref. [15] for a recent review), Second RPA (SRPA) [16,17] or particle-vibration coupling (PVC) [6,18,19] techniques have shown to be instrumental to quantitatively address refined aspects of GRs such as their (Landau) width.…”