Search for Intrinsic Excitations in 152Sm

TL;DR

This study investigates the low-energy excited states of 152Sm using Coulomb excitation and neutron scattering, finding no evidence for two-phonon quadrupole vibrational states but identifying a 2+ K=2 state and a probable 3+ band member.

Contribution

The paper provides experimental data on 152Sm's excited states, challenging the expected two-phonon excitations and identifying specific non-phonon states.

Findings

No two-phonon K=0+ quadrupole vibrational states found

Identification of a 2+ K=2 state with strong E2 decay

Probable 3+ band member established

Abstract

The 685 keV excitation energy of the first excited 0+ state in 152Sm makes it an attractive candidate to explore expected two-phonon excitations at low energy. Multiple-step Coulomb excitation and inelastic neutron scattering studies of 152Sm are used to probe the E2 collectivity of excited 0+ states in this "soft" nucleus and the results are compared with model predictions. No candidates for two-phonon K=0+ quadrupole vibrational states are found. A 2+, K=2 state with strong E2 decay to the first excited K=0+ band and a probable 3+ band member are established.