8B + 208Pb Elastic Scattering at Coulomb Barrier Energies

M La Commara,S Kubono ,E Strano ,M Nicoletto,N Imai,Y H Kim ,C Parascandolo,C Signorini,C J Lin ,Yukihiro Sakaguchi ,J Grębosz ,C Manea,C Boiano,Sohee Jeong ,D Torresi,F Soramel,M Mukai,D Pierroutsakou,H Yamaguchi,P Di Meo,M Mazzocco,L Yang,N Iwasa ,D Kahl,Takashi Teranishi ,H M Jia ,H Ishiyama ,Yutaka Watanabe ,S Kimura ,Y Wakabayashi ,A Boiano,Á M Sánchez-Benítez ,H Miyatake ,T Nakao ,Y Hirayama ,Y Yang

doi:10.1088/1742-6596/966/1/012010

Abstract

The scattering process of weakly-bound nuclei at Coulomb barrier energies provides deep insights on the reaction dynamics induced by exotic nuclei. Within this framework, we measured for the first time the scattering process of the short-lived Radioactive Ion Beam (RIB) 8B (Sp = 0.1375 MeV) from a 208Pb target at 50 MeV beam energy. The 8B RIB was produced by means of the in-flight facility CRIB (RIKEN, Japan) with an average intensity on target of 10 kHz and a purity about 25%. Elastically scattering ions were detected in the angular range θc.m. = 10°-160° by means of the detector array EXPADES. A preliminary optical model analysis indicates a total reaction cross section of about 1 b, a value, once reduced, 2-3 times larger than those obtained for the reactions induced by the stable weakly-bound projectiles 6,7Li on a 208Pb target in the energy range around the Coulomb barrier.

Highlights

Despite great efforts in experiments and theories over the past decades, the precise description on the influence of breakup channel on fusions is still elusive, due to the limited knowledge on the breakup process, especially for the unstable reaction systems. More knowledge in this framework can be obtained starting from the investigation of simple processes, as elastic scattering
It is well accepted by the nuclear physicists community that the presence of a proton halo or skin may heavily influence the behavior of an exotic nucleus in terms of nuclear reaction mechanism as well as can strongly influence its structure [1] [2]
Elastic scattering data for proton-halo isotopes around the Coulomb barrier are still not enough to fully understand the dynamics of this process. 8B is a proton-drip-line β−decaying isotope, conveying pretty much interest because of the role it plays in the production of high-energy neutrinos in the sun and its quite unusual structure, being considered a one-proton halo nucleus [3]

Summary

Introduction

Nuclei far from β−stability valley, as 6He, 11Be, 8B, are very interesting because of their peculiarities as far as their structure and their way to interact with other nuclei are concerned, indeed during the last decades many theoretical and experimental efforts have been devoted to Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Published under licence by IOP Publishing Ltd

Discussion and outlook