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

Abstract 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 7 Be and R m = 2.58 ( 6 ) fm for 8 B were obtained. The radial density distribution deduced for 8 B 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.