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Delayed neutron measurements from fast fission of actinide waste isotopes
dc.creator | Charlton, William S. | |
dc.date.accessioned | 2012-06-07T22:48:09Z | |
dc.date.available | 2012-06-07T22:48:09Z | |
dc.date.created | 1997 | |
dc.date.issued | 1997 | |
dc.identifier.uri | https://hdl.handle.net/1969.1/ETD-TAMU-1997-THESIS-C4427 | |
dc.description | Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to digital@library.tamu.edu, referencing the URI of the item. | en |
dc.description | Includes bibliographical references. | en |
dc.description | Issued also on microfiche from Lange Micrographics. | en |
dc.description.abstract | A study was performed to determine the delayed neutron emission properties from fast fission of several actinide waste isotopes. The specific isotopes evaluated were U-235, Np-237, and Am-243. A calculational technique based on the microscopic method was used to predict initial guesses for the delayed neutron parameters (group decay constants and yields). Based on these calculations, an alternate "seven-group" structure, in contrast to the traditional "six-group" structure used previously, was suggested which would yield a superior fit to the measured data. A series of measurements were performed to test the hypothesis suggested by this alternate group structure. Using a set of highly purified actinide samples (provided by Oak Ridge National Laboratory), the delayed neutron emission decay constants and yields for six groups of the "seven-group" structure were measured for U-235, Np-237, and Am-243. These experiments were performed using the Texas A&M University Nuclear Science Center Reactor, a quick pneumatic transfer system, an integrated computer control and counting system, and a specially designed in-core irradiation device. The values for the total delayed neutron yield (per 100 fissions) from fast-neutron induced fission of U-235, Np237, and Am-243 were determined to be 1.67 ︢0.08, 1.14 ︢0.07, 0.86 ︢0.05, respectively. The newly measured values were compared with other values recommended by Keepin et al., Waldo et al., Saleh et al., and Brady and England. Good agreement was found in all cases. The "seven-group" structure was shown to yield a superior fit to the measured data, as well as, provide a more direct correlation between delayed neutron groups and their associated delayed neutron precursors. | en |
dc.format.medium | electronic | en |
dc.format.mimetype | application/pdf | |
dc.language.iso | en_US | |
dc.publisher | Texas A&M University | |
dc.rights | This thesis was part of a retrospective digitization project authorized by the Texas A&M University Libraries in 2008. Copyright remains vested with the author(s). It is the user's responsibility to secure permission from the copyright holder(s) for re-use of the work beyond the provision of Fair Use. | en |
dc.subject | nuclear engineering. | en |
dc.subject | Major nuclear engineering. | en |
dc.title | Delayed neutron measurements from fast fission of actinide waste isotopes | en |
dc.type | Thesis | en |
thesis.degree.discipline | nuclear engineering | en |
thesis.degree.name | M.S. | en |
thesis.degree.level | Masters | en |
dc.type.genre | thesis | en |
dc.type.material | text | en |
dc.format.digitalOrigin | reformatted digital | en |
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