Coulomb excitation of exotic nuclei at the R3B-LAND setup

TL;DR

This study investigates the Coulomb excitation of exotic Ni isotopes at high energies using the R3B-LAND setup, revealing detailed nuclear structure information including the GDR and low-lying strength in 68Ni.

Contribution

First measurement of Coulomb excitation of exotic Ni isotopes at GSI with kinematically complete data and detailed decay analysis.

Findings

Observation of GDR and low-lying strength in 68Ni

Low-lying strength exhausts 4.1% of E1 sum rule

Non-statistical decay branching ratio of 24%

Abstract

Exotic Ni isotopes have been measured at the R3B-LAND setup at GSI in Darmstadt, using Coulomb excitation in inverse kinematics at beam energies around 500 MeV/u. As the experimental setup allows kinematically complete measurements, the excitation energy was reconstructed using the invariant mass method. The GDR and additional low-lying strength have been observed in 68Ni, the latter exhausting 4.1(1.9)% of the E1 energy-weighted sum rule. Also, the branching ratio for the non-statistical decay of the excited 68Ni nuclei was measured and amounts to 24(4)%.