Fine structure of the isoscalar giant quadrupole resonance in 40Ca due to Landau damping?

The fragmentation of the Isoscalar Giant Quadrupole Resonance (ISGQR) in 40Ca has been investigated in high energy-resolution experiments using proton inelastic scattering at E_p = 200 MeV. Fine structure is observed in the region of the ISGQR and its characteristic energy scales are extracted from the experimental data by means of a wavelet analysis. The experimental scales are well described by Random Phase Approximation (RPA) and second-RPA calculations with an effective interaction derived from a realistic nucleon-nucleon interaction by the Unitary Correlation Operator Method (UCOM). In these results characteristic scales are already present at the mean-field level pointing to their origination in Landau damping, in contrast to the findings in heavier nuclei and also to SRPA calculations for 40Ca based on phenomenological effective interactions, where fine structure is explained by the coupling to two-particle two-hole (2p-2h) states.Comment: Phys. Lett. B, in pres

Evidence for Fragmentation of "Stretched" 6- Strength in 28-Si(p,p')28-Si

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Measurements of the Spin Observables D_NN' and P in the Inelastic Proton Scattering from 12-C and 16-O at 200 MeV

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The High Resolution K600 Spectrometer

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Shell Structure Studies in the Pb-Region

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Investigation of the Effective NN Interaction Through 28-Si(p,p')28-Si Polarization Transfer

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Test of a Density-Dependent Effective Interaction Using In-Plane 28-Si(p,p')28-Si Polarization Transfer Measurements

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K600 Small Angle Operation

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Shell Structure Studies in the Pb-Region

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Investigation of High-Spin, Particle-Hole Excitation in 208-Pb with Inelastic Proton Scattering at 200 MeV

This research was sponsored by the National Science Foundation Grant NSF PHY-931478