Probing the quadrupole transition strength of 15C via deuteron inelastic scattering

TL;DR

This study investigates the quadrupole transition strength of 15C using deuteron inelastic scattering, providing experimental data and theoretical comparisons that enhance understanding of neutron-rich carbon isotopes.

Contribution

It introduces experimental measurements of quadrupole transition in 15C via inverse kinematics and compares results with ab-initio calculations, revealing core decoupling effects.

Findings

Measured matter deformation length δd = 1.04(11) fm

Determined neutron/proton matrix element ratio Mn/Mp = 3.6(4)

Supported moderate core decoupling in 15C

Abstract

Deuteron elastic scattering from 15C and inelastic scattering reactions to the first excited state of 15C were studied using a radioactive beam of 15C in inverse kinematics. The scattered deuterons were measured using HELIOS. The elastic scattering differential cross sections were analyzed using the optical model. A matter deformation length {\delta}d = 1.04(11) fm has been extracted from the differential cross sections of inelastic scattering to the first excited state. The ratio of neutron and proton matrix elements Mn/Mp = 3.6(4) has been determined from this quadrupole transition. Neutron effective charges and core-polarization parameters of 15C were determined and discussed. Results from ab-initio no-core configuration interaction calculations were also compared with the experimental observations. This result supports a moderate core decoupling effect of the valence neutron in 15C similarly to its isotone 17O, in line with the interpretation of other neutron-rich carbon isotopes.