2003/07/29 by E. Sauvan, F. Cârstoiu, F. Carstoiu +16
Physics and Astronomy · #Astronomical and nuclear sciences #Nuclear Physics and Applications #Nuclear physics research studies #nucl-ex
paper · pdf · doi:10.1103/physrevc.69.044603
published as Phys.Rev. C69 (2004) 044603 · 50 pages, 19 figures, submitted to Phys. Rev. C
arxiv created 2003/07/29 · openalex publication_date 2004/04/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A study of high-energy (43--68\phantom\rule0.3em0exMeV∕nucleon) one-neutron removal reactions on a range of neutron-rich psd-shell nuclei (Z=5--9,\phantom\rule0.3em0exA=12--25) 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 psd 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 15B,17C,19--21N,21,23O,23--25F. In addition to the large spectroscopic amplitudes for the \ensuremathν2s1∕2 intruder configuration in the N=9 isotones, 14B and 15C, significant \ensuremathν2s1∕22 admixtures appear to occur in the ground state of the neighboring N=10 nuclei 15B and 16C. Similarly, crossing the N=14 subshell, the occupation of the \ensuremathν2s1∕2 orbital is observed for 23O, 24,25F. Recent claims of a modified shell structure for 23O are investigated and the original suggestion of a ground state J^\ensuremathπ=1∕2+ 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.