Validation of the Be 10 Ground-State Molecular Structure Using Be 10 (p,pα) He 6 Triple Differential Reaction Cross-Section Measurements

The cluster structure of the neutron-rich isotope Be10 has been probed via the (p,pα) reaction at 150 MeV/nucleon in inverse kinematics and in quasifree conditions. The populated states of He6 residues were investigated through missing mass spectroscopy. The triple differential cross section for the ground-state transition was extracted for quasifree angle pairs (θp,θα) and compared to distorted-wave impulse approximation reaction calculations performed in a microscopic framework using successively the Tohsaki-Horiuchi-Schuck-Röpke product wave function and the wave function deduced from antisymmetrized molecular dynamics calculations. The remarkable agreement between calculated and measured cross sections in both shape and magnitude validates the molecular structure description of the Be10 ground-state, configured as an α-α core with two valence neutrons occupying π-type molecular orbitals.