Inelastic scattering of 72,74Ni off a proton target

M L Cortés ,Zs Dombrádi ,M Sasano ,J Lee ,J.-M Gheller ,A Peyaud ,S Koyama ,F Browne ,K Yoneda ,Yoshinori Shiga ,M Lettmann ,R Taniuchi ,I Stefan ,D Suzuki ,Zs Vajta ,T Uesaka ,S Nishimura ,D Steppenbeck ,P Doornenbal ,G Authelet ,L X Chung ,H Wang ,F Giacoppo ,C Shand ,D Calvet ,F Château ,P.-A Söderström ,A Obertelli ,H Otsu ,Clara Péron ,T Isobe ,Z Korkulu ,M Nııkura ,M Matsushita ,Takamichi Miyazaki ,C Louchart ,Y Kubota ,S Franchoo ,K Hadyńska-Klȩk ,V Werner ,S Ota ,Satoshi Takeuchi ,E Šahin ,A Gillibert ,T Motobayashi ,S Momiyama ,H Baba ,K Matsui ,Z Patel ,A Gottardo ,H Sakuraï ,V Lapoux ,N Pietralla ,C Santamaria ,E C Pollacco ,L Olivier ,J.-Y Roussé ,T Sumikama ,R Lozeva ,J Wu ,A Corsi ,A Delbart ,Z Y Xu

doi:10.1088/1742-6596/724/1/012008

Abstract

Inelastic scattering of 72,74Ni off a proton target was performed at RIBF, RIKEN, Japan. The isotopes were produced by the fission of 238U on a thick Beryllium target and were then selected and identified on an event-by-event basis using the BigRIPS separator. Selected isotopes were focused onto the liquid hydrogen target of the MINOS device and gamma rays from the reactions were measured with the DALI2 array. The energy of the ions in the middle of the target was 213 MeV/u. Outgoing particles were identified using the ZeroDegree spectrometer. Here, we report on the current status of the data analysis and preliminary results for the proton inelastic scattering cross sections for both isotopes.

Highlights

The study of very neutron-rich exotic nuclei has recently attracted a great deal of scientific attention and offers a unique opportunity to test the shell evolution as a function of isospin
We report on a second measurement of the proton inelastic scattering cross-section for 74Ni performed at intermediate energies, as well as the first measurement of proton inelastic scattering of 72Ni
Experimental setup The experiment was performed at the Radioactive Isotope Beam Factory (RIBF), operated by the RIKEN Nishina Center and the Center for Nuclear Study of the University of Tokyo as a part of the first SEASTAR campaign [7]

Summary

Introduction

The study of very neutron-rich exotic nuclei has recently attracted a great deal of scientific attention and offers a unique opportunity to test the shell evolution as a function of isospin. This evolution reflects properties of the nucleon-nucleon interaction, as well as the importance of the proton-neutron tensor force [1], and allows a better insight into the fundamental properties of the nuclear force. In order to distinguish the relative importance of the contribution of protons and neutrons to the collectivity, neutron and proton multipole matrix elements should be obtained. Following the approach by Bernstein et al [2, 3], the ratio of neutron-toproton matrix elements can be expressed as

Methods

Results

Conclusion