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We analyze the recently obtained new data on the partial cross sections and parallel momentum distributions for transitions to ground as well as excited states of the 16 C core, in the one-neutron removal reaction 197 Au( 17 C, 16 Cγ)X at the beam energy of 61 MeV/nucleon. The Coulomb and nuclear breakup components of the one-neutron removal cross sections have been calculated within a finite range distorted wave Born approximation theory and an eikonal model, respectively. The nuclear contributions dominate the partial cross sections for the core excited states. By adding the nuclear and Coulomb cross sections together, a reasonable agreement is obtained with the data for these states. The shapes of the experimental parallel momentum distributions of the core states are described well by the theory.PACS numbers: 24.10.Eq., 25.60.-t, 25.60.Gc, 24.50.+g KEYWORD: structure of neutron rich nuclei, Coulomb and nuclear breakup, finite range DWBA and eikonal models 1

Measurements of deexcitation g rays in coincidence with the momentum distribution of the projectile residues produced in reactions of the type 9 Be͑ 28 P, 27 Si 1 g͒X at energies around 65 MeV͞u are used to study single-nucleon stripping to individual states. The cross sections are compared with calculations based on an eikonal model description of the reaction and the shell model. The measurements indicate that the halo character of the ground state and other detailed spectroscopic information can be derived using knockout reactions in inverse kinematics. [S0031-9007(98)

The structure of the neutron-rich carbon isotopes 16,17,19 C has been investigated using one-neutron knockout reactions on a 9 Be target at approximately 60 MeV/nucleon. Partial cross sections and associated momentum distributions corresponding to final states of the 15,16,18 C residues were measured and compared with predictions based on a shell-model theory and an eikonal model of the reaction mechanism. Spectroscopic factors and l-value assignments are given. The ground-state spins of 17,19 C are ϩ , respectively. It is suggested that the accepted one-neutron separation energy for the ground state of 19 C needs to be revised upwards.

The momentum distributions of the residual nuclei after one-neutron removal have been measured in coincidence with gamma rays identifying the distributions associated with the excited and ground state levels of these residues. These differential partial cross sections map the momentum content of the removed-nucleon wave functions and their description provides an exacting test of the reaction dynamics. Momentum distribution data when populating the 14 C and 10 Be ground states show a low-high momentum asymmetry that is incompatible with the hitherto used eikonal descriptions. A fully dynamical coupled discretized continuum channels description of the elastic breakup mechanism is shown to provide an understanding of this new observation which is most pronounced for weakly bound, s-wave, nuclear halo states. This interpretation is clarified further by an analysis of the momentum distributions as a function of the angle of detection of the heavy ground state residues.

Breakup temperatures were deduced from double ratios of isotope yields for target spectators produced in the reaction 197 The good agreement with the breakup temperatures measured previously for projectile spectators at an incident energy of 600 MeV per nucleon confirms the universality established for the spectator decay at relativistic bombarding energies. The measured temperatures also agree with the breakup temperatures predicted by the statistical multifragmentation model. For these calculations a relation between the initial excitation energy and mass was derived which gives good simultaneous agreement for the fragment charge correlations.The energy spectra of light charged particles, measured at θ lab = 150• , exhibit Maxwellian shapes with inverse slope parameters much higher than the breakup temperatures. The statistical multifragmentation model, because Coulomb repulsion and sequential decay processes are included, yields light-particle spectra with inverse slope parameters higher than the breakup temperatures but considerably below the measured values. The systematic behavior of the differences suggests that they are caused by light-charged-particle emission prior to the final breakup stage. Keywords:197 Au projectiles and targets, E/A = 600 and 1000 MeV; measured fragment cross sections, isotopic yield ratios; deduced breakup temperatures, pre-breakup emission; analysis using quantum statistical and statistical multifragmentation models.