Are There Nuclear Structure Effects on the Isoscalar Giant Monopole Resonance and Nuclear Incompressibility near A~90?

TL;DR

This study uses high-precision alpha scattering to investigate if nuclear shell effects influence the isoscalar giant monopole resonance and nuclear incompressibility near mass number 90, finding no such influence.

Contribution

It provides experimental evidence that nuclear shell structure does not affect nuclear incompressibility near A~90, challenging recent claims.

Findings

ISGMR strength distributions are similar for $^{90, 92}$Zr and $^{92}$Mo

Nuclear incompressibility is unaffected by shell effects near A~90

Results contradict recent measurements suggesting shell influence

Abstract

"Background-free" spectra of inelastic $\alpha$-particle scattering have been measured at a beam energy of 385 MeV in $^{90, 92}$Zr and $^{92}$Mo at extremely forward angles, including 0$^{\circ}$. The ISGMR strength distributions for the three nuclei coincide with each other, establishing clearly that nuclear incompressibility is not influenced by nuclear shell structure near $A\sim$90 as was claimed in recent measurements.