Nuclear matter distributions in the 6He and 8He nuclei from differential cross sections for small-angle proton elastic scattering at intermediate energy

Abstract A Glauber based analysis of the experimental cross sections for small-angle elastic p 6,8 He scattering at 0.7 GeV has been performed. The radii and radial shape of the 6 He and 8 He nuclei have been determined using phenomenological nuclear density distributions with two free parameters. The deduced shapes of the 6 He and 8 He nuclear matter radial distributions conform with the concept that both nuclei consist of an α -particle core and a significant neutron halo. The accuracy of the theoretical analysis of the elastic-scattering cross-section data is discussed, and possible sources of systematic uncertainty related to some basic limitations in the applied method are outlined. The experimental p 6,8 He elastic-scattering cross sections have also been utilized for probing the matter density distributions resulting from various nuclear microscopic models. Besides, the sensitivity of the total p 6,8 He reaction cross sections to the size of the 6 He and 8 He nuclei has been considered.