Continuum discretised coupled-channels(CDCC) method with a ^(10)Be(0^+) + n two-body cluster model is applied to systematically analyze the elastic scattering of the halo nucleus ^(11)Be from the proton target at various incident energies below 100 MeV/nucleon.Using the renormalized ^(10)Be- p potential deduced from the ^(10)Be+ p elastic scattering data, the differential cross sections of ^(11)Be + p scattering are well reproduced by the CDCC calculations without any further adjustment parameters, demonstrating the applicability of this approach for describing the scattering of exotic nuclei based on the scattering of the less exotic core nuclei.
A cluster-transfer experiment of ~9Be(~9Be,^(14)C→α+^(10)Be)α at an incident energy of 45 MeV was carried out in order to investigate the molecular structure in high-lying resonant states in ^(14)C.This reaction is of extremely large Q-value,making it an excellent case to select the reaction mechanism and the final states in outgoing nuclei.The high-lying resonances in ^(14)C are reconstructed for three sets of well discriminated final states in ^(10)Be.The results confirm the previous decay measurements with clearly improved decay-channel selections and also show a new state at 23.5(1) MeV.The resonant states at 22.4(3) and 24.0(3) MeV decay primarily into the typical molecular states at about 6 MeV in ^(10)Be,indicating a well developed cluster structure in these high-lying states in ^(14)C.Further measurements of more states of this kind are suggested.
A transfer-reaction experiment of ~9Be(~9Be,^(10)Be)~8Be was performed at a beam energy of 45 Me V.Excited states in ^(10)Be up to 18.80 Me V are produced using missing mass and invariant mass methods.Most of the observed high-lying resonant states,reconstructed from theα+~6He and t+~7Li decay channels,agree with the previously reported results.In addition,two new resonances at 15.6 and 18.8 Me V are identified from the present measurement.The 18.55 Me V state is found to decay into both the t + ~7Lig:s: and t + ~7Li?(0.478 MeV) channels, with a relative branching ratio of 0:93 ± 0:33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei.
From an inelastic excitation and breakup experiment with a12Be beam at 29 MeV/u,a large4He+8He cluster decay width of 1.1(2)MeV is determined for a state at an excitation energy of 10.3 MeV and with a spin parity of 0+.By using the R-matrix analysis,a cluster spectroscopic factor of 0.53(10)is extracted from the cluster partial width,providing a strong support for the clustering structure in12Be.A specially designed zero-degree telescope played an essential role in the present experiment and has been demonstrated to be a promising tool in future studies of the molecular-like resonances near the cluster separation threshold.
