Weakly bound Borromean structures of the exotic ^6,8He nuclei through direct reactions on proton

The data set of the direct reactions induced by the radioactive nuclei ^{6, 8}He can be used as benchmarks to test the validity of the microscopic structure theories. The reactions were analyzed and compared to microscopic calculations including various structure inputs. The interpretation for the structure of He isotopes is compared to the ones proposed via other probes. The consistency of the various data sets and of the reaction analysis using structure models is discussed. The root mean square radii of the matter and neutron densities, and the multipole moments M_{p, n} and B(E2) values are extracted in our approach and compared to the previous experiments and to the theories. From this comparison, we can discuss and point out the microscopic inputs of the models (like correlations, continuum-coupling effects), which are required to reach a consistent understanding for both the radii and the spectroscopy of the nuclei close to the drip-line. (orig.)