High resolution studies of projectile breakup at intermediate energies /
This dissertation is a study of heavy ion breakup reactions
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1996.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739667901&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | This dissertation is a study of heavy ion breakup reactions at intermediate energies. The main focus is on 16 O breakup in view of its possible astrophysical application. A 30 AMeV 16 O beam from the Texas A&M K500 cyclotron was used to irradiate 58Ni, 120 Sn, and 208 Pb targets. Two detectors were placed in the focal plane of an Enge Split-Pole Magnetic Spectrograph. Measurements were carried out at laboratory angles of 3[], 5[], 8[], and 11[]. Additional measurements were made with 30A MeV 2ONe incident on 12C, 58Ni, 120Sn, and 208Pb targets. The 16 O elastic breakup component was found to be dominated by discrete peaks due to the sequential breakup of the projectile. Little, if any, continuum component was observed. The elastic breakup data were compared to theoretical calculations to evaluate the relative importance of Coulomb and nuclear breakup. Both the shapes and absolute magnitudes of the double differential cross sections for the sequential breakup of 30 AMeV 16 O on 120Sn and 208Pb nuclei were reasonably well reproduced by a coupled channels calculation using cluster model wavefunctions. The calculations indicate a strong contribution from the nuclear breakup even at small angles. In the 16 O experiments, breakup was observed over a broad range of inelasticities while in the 20Ne measurements mainly elastic breakup is observed. The relative kinetic energy spectra for inelastic breakup show many discrete resonances and a possible continuum component. A simulation was developed for the sequential breakup of 16 O into 12C + [] using all known states in 16 O up to E* = 25 MeV. Using an initial thermal population, the relative energy spectra for energy losses greater than = 30 MeV are well reproduced. This again shows the dominance of a sequential mechanism. Fits to the data give apparent temperatures which are surprisingly large. |
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| Item Description: | Vita. "Major Subject: Chemistry". |
| Physical Description: | xiii, 140 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 136-139. |