We investigate the Coulomb breakup of neutron rich nuclei 11 Be and 19,17,15 C within a theory developed in the framework of Distorted Wave Born Approximation. Finite range effects are included by a local momentum approximation, which allows incorporation of realistic wave functions for these nuclei in our calculations. Energy and angular as well as parallel momentum distributions of the fragments emitted in the breakup of these nuclei on heavy targets have been calculated using several structure models for their ground state. Comparison with the available experimental data shows that the results are selective about the ground state wave function of the projectile. Our investigations confirm that the nuclei 11 Be, 19 C and 15 C have a one-neutron halo structure in their ground states. However, for 17 C such a structure appears to be less likely. Calculations performed within our method have also been compared with those from an adiabatic model and the results are discussed. PACS numbers: 21.10. Hw, 24.10.Eq, 25.60.Gc Key words: Coulomb breakup, one-neutron halo nucleus, effects of projectile structure.

No abstract

No abstract

No abstract

We study the breakup of one-neutron halo nuclei in the Coulomb field of a target nucleus. In the post-form distorted wave Born approximation theory of this reaction, with only Coulomb distortions in the entrance and the outgoing channels, an analytic solution for the breakup T -matrix is known. We study this T -matrix and the corresponding cross-sections numerically. This formula can be related to the first order semiclassical treatment of the electromagnetic dissociation. This theory contains the electromagnetic interaction between the core and the target nucleus to all orders. We show that higher order effects (including postacceleration) are small in the case of higher beam energies and forward scattering. We investigate the beam energy dependence of the postacceleration effects. They are found to be quite important for smaller beam energies (slow collisions), but almost negligible at larger ones.PACS numbers: 24.10.Eq, 25.60.Gc, 24.50.+g KEYWORD: Finite range DWBA theory of Coulomb breakup, first order and higher order contributions, postacceleration effects

We investigate the Coulomb part of the one-neutron removal cross section in breakup reactions of the neutron rich nuclei 11 Be and 19 C. Approximate Coulomb breakup amplitudes are derived from two distinct theoretical viewpoints. One of these uses an approximation to the distorted-wave Born approximation. The other assumes an adiabatic treatment of the projectile excitation to the low energy continuum. Both approaches include approximately the finite range of the interaction between the breakup fragments and so can treat nons-wave projectiles. Calculations are analyzed and compared with available experimental data for total oneneutron removal cross sections, neutron angular distributions, heavy charged fragment momentum distributions, and excitation energy spectra for breakup on high Z targets. ͓S0556-2813͑98͒00108-3͔ PACS number͑s͒: 24.10. Eq, 25.60.Ϫt, 25.70.Mn

We investigate the structure of the neutron rich nucleus 19 C through studies of its breakup in the Coulomb field of target nuclei. The breakup amplitude is calculated within an adiabatic treatment of the projectile excitation, which allows the use of the realistic wave functions for the relative motion between the fragments in the ground state of the projectile. The angular distribution of the center of mass of 19 C, longitudinal momentum distribution of 18 C, and relative energy spectrum of the fragments ͑neutron-18 C) following the breakup of 19 C on heavy targets at beam energies below 100 MeV/nucleon have been computed using different configurations for the ground state wave function of 19 C. In all cases, the data seem to favor a 18 C(0 ϩ ) 1s 1/2 configuration for the ground state of 19 C, with a one-neutron separation energy of 0.53 MeV.

No abstract