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All the 16F levels are unbound by proton emission. To date the four low-lying 16F levels below 1 MeV have been experimentally identified with well established spin-parity values and excitation energies with an accuracy of 4 - 6 keV. However, there are still considerable discrepancies in their level widths. The present work aims to explore these level widths through an independent method. The angular distributions of the 15N(7Li,6Li)16N reaction leading to the first four states in 16N were measured using a high-precision Q3D magnetic spectrograph. The neutron spectroscopic factors and the asymptotic normalization coefficients for these states in 16N were then derived based on distorted wave Born approximation analysis. The proton widths of the four low-lying resonant states in 16F were obtained according to charge symmetry of strong interaction. [ABSTRACT FROM AUTHOR]

The angular distributions of the 12C(11B,11B)12C and 12C(11B,12C)11B reactions have been measured at an incident energy of 50 MeV by using the high resolution Q3D magnetic spectrometer of the HI-13 tandem accelerator at China Institute of Atomic Energy, Beijing. The optical potential parameters of the 11B + 12C system are determined by fitting the angular distribution of the elastic scattering and then used to predict the cross sections of the elastic transfer reaction leading to the ground state in l 2C based on distorted-wave Born approximation (DWBA) analysis. Taking into account the interference between the elastic scattering and the elastic transfer processes, the proton spectroscopic factor of the, 12C ground state is extracted to be 2.15 ± 0.23 by constraining the geometrical parameters r0 and a using the rms radius of the valence proton in the 12C ground state. [ABSTRACT FROM AUTHOR]

The 13C(9Be,8Li)14N angular distribution was measured with a 9Be beam of 40 MeV. The proton spectroscopic factor of the 9Be ground state was extracted to be 0.73 ± 0.15 by the normalization of the calculated differential cross sections with the distorted-wave Born approximation (DWBA) to the experimental data. The spectroscopic factor was compared to existing theoretical and experimental values. [ABSTRACT FROM AUTHOR]

The C(Li, He) N reactions were measured at E (Li) = 34 MeV with the Q3D magnetic spectrometer of the HI-13 tandem accelerator, and the first peaks of the angular distributions were obtained for the first time. The N proton spectroscopic factors were extracted to be 0.67±0.09 and 0.73±0.10 , respectively. Using the C( p, γ) N direct capture S( E) factors derived by the spectroscopic factors, the direct measurement data for both 1 and 0 resonances were well fitted via updating the resonance parameters, and then the total astrophysical C( p, γ) N S( E) factors and reaction rates were determined at stellar energies. The present work offers an independent examination to the existing results of the C( p, γ) N reaction. [ABSTRACT FROM AUTHOR]

Abstract: Angular distributions of 2H(6He,7Li)n and 12C(7Li,6He)13N reactions were measured at the HI-13 tandem accelerator, Beijing. Asymptotic normalization coefficient (ANC) of 13N →12C + p was derived to be through distorted wave Born approximation (DWBA) analysis, which was then used to deduce the astrophysical S(E) factors for direct capture in 12C(p,γ)13N at energies of astrophysical relevance. [Copyright &y& Elsevier]

Several zirconium isotopes are in the path of slow neutron capture (s) process, and the direct components of (n,γ) reactions can be derived from their neutron spectroscopic factors. In the present work, the angular distributions of (12C,13C) and (13C,12C) reactions on targets 90,92,94,96Zr were obtained using the high-precision Q3D magnetic spectrograph at the Beijing HI-13 tandem accelerator in China Institute of Atomic Energy. The distorted-wave Born approximation calculations were performed to extract the spectroscopic factors, using three different sets of Woods-Saxon potential parameters for these heavy-ion systems. The neutron spectroscopic factors for the ground state of 90-97Zr have been obtained and compared with other experimental data. [ABSTRACT FROM AUTHOR]