Abstract
A study of high-energy one-neutron removal reactions on a range of neutron-rich -shell nuclei has been undertaken. The inclusive longitudinal and transverse momentum distributions for the core fragments together with the cross sections have been measured for breakup on a carbon target. Momentum distributions for reactions on tantalum were also measured for a subset of nuclei. An extended version of the Glauber model incorporating second-order noneikonal corrections to the Jeukenne, Lejeune, and Mahaux parametrization of the optical potential has been used to describe the nuclear breakup, while the Coulomb dissociation is treated within first-order perturbation theory. The projectile structure has been taken into account via shell-model calculations employing the interaction of Warburton and Brown. Both the longitudinal and transverse momentum distributions together with the integrated cross sections were well reproduced by these calculations and spin-parity assignments are thus proposed for . In addition to the large spectroscopic amplitudes for the intruder configuration in the isotones, and , significant admixtures appear to occur in the ground state of the neighboring nuclei and . Similarly, crossing the subshell, the occupation of the orbital is observed for , . Recent claims of a modified shell structure for are investigated and the original suggestion of a ground state is confirmed. Analysis of the longitudinal and transverse momentum distributions reveals that both carry spectroscopic information, often of a complementary nature. The general utility of high-energy nucleon removal reactions as a spectroscopic tool is also examined.
12 More- Received 13 August 2003
DOI:https://doi.org/10.1103/PhysRevC.69.044603
©2004 American Physical Society