Nuclear-matter distribution in the proton-rich nuclei Be-7 and B-8 from intermediate energy proton elastic scattering in inverse kinematics

摘要

Absolute differential cross sections for elastic p(7)Be and p(8)B small-angle scattering were measured in inverse kinematics at an energy of 0.7 GeV/u at GSI Darmstadt. The hydrogen-filled ionization chamber IKAR was used as an active target to detect the recoil protons. The projectile tracking and isotope identification were performed with multi-wire proportional chambers and scintillation detectors. The measured cross sections were analysed using the Glauber multiple-scattering theory. The root-mean-square (rms) nuclear matter radii R-m = 2.42(4) fm for Be-7 and R-m = 2.58(6) fm for B-8 were obtained. The radial density distribution deduced for B-8 exhibits a proton halo structure with the rms halo radius R-h = 4.24(25) fm. A comparison of the deduced experimental radii is displayed with existing experimental and theoretical data. (C) 2019 Elsevier B.V. All rights reserved.