AbstractAbstract
[en] The specific purpose of this work is to provide a better understanding of the 14C level structure; the general purpose is to provide the details for using shell model calculations in R-matrix analyses. Using the TOF facilities of the Ohio University Accelerator Laboratory, the elastic and first 3 inelastic differential scattering cross sections for 13C + n were measured at 69 energies for 4.5 ≤ E/sub n/ ≤ 11 MeV. A multiple scattering code was developed which provided a simulation of the experimental scattering process allowing accurate corrections to the small inelastic data. The integrated 13C(n,α)10Be cross section is estimated. The sequential 2n-decay of 14C states populated by 13C + n was observed. A shell model code was developed. Normal and nonnormal parity calculations were made for the lithium isotopes using a new two-body interaction. The results for 5Li predict the 2s/sub 1/2/ and 1d/sub 5/2/ single-particle states to be located below the 3/2+ state. Similar calculations were made for 13C, 13N, and 14C. Results for 13C and 13N show for E/sub x/ < 10 MeV the Thomas-Ehrman shifts are related to the 2s/sub 1/2/ single-particle energies. For 7Li and 14C, 2 h-barω calculations were done. Shell model calculations generated the R-matrix parameters for the elastic and first 3 inelastic channels of 13C + n. After adjusting some energies, the predicted structure generally agrees with experiment for E/sub n/ < 4 MeV. Previous elastic 13C + n data were refit to replace R0 background terms by more realistic broad states and to get better agreement with model calculations. R-matrix fitting of the full data set produced new 14C level information. For E/sub n/ > 4 MeV (E/sub x/ > 12 MeV), 5 states are given definite J/sup π/ assignments; 3, tentative assignments. 122 refs., 91 figs., 30 tabs
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Mar 1987; 518 p; Available from NTIS, PC A22/MF A01; 1 as DE87008246; Portions of this document are illegible in microfiche products.; Thesis.
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Report
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Thesis/Dissertation
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Descriptors (DEC)
BARYON REACTIONS, BERYLLIUM ISOTOPES, BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, CARBON ISOTOPES, CHARGED PARTICLES, ENERGY RANGE, EVEN-EVEN NUCLEI, HADRON REACTIONS, HELIUM IONS, IONIZING RADIATIONS, IONS, ISOTOPES, LIGHT NUCLEI, MATHEMATICAL MODELS, MEV RANGE, NUCLEAR MODELS, NUCLEAR REACTIONS, NUCLEI, NUCLEON REACTIONS, RADIATIONS, RADIOISOTOPES, SCATTERING, TARGETS, YEARS LIVING RADIOISOTOPES
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