parity assignment of the pronounced structure in the radiative capture of neutrons by /sup 238/U below 100 keV

Moore, M S; Corvi, F; Mewissen, L; Poortmans, F

Title: parity assignment of the pronounced structure in the radiative capture of neutrons by /sup 238/U below 100 keV

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Abstract

Some years ago, Perez and de Saussure reported evidence for intermediate structure in the radiative capture cross sections of /sup 238/U. More recently, these and additional data, obtained by a different experimental technique but which showed the same non-statistical behavior, were analyzed by Perez et al. Under the assumption that the structure could be attributed to doorway states in the p/sup 3/2/ neutron channel. The results of an experimental determination of the parity of the structure, using neutron capture-gamma ray spectroscopy are reported. Much of the structure below 50 keV appears to be due to s-wave interactions. The magnitude of the fluctuations is much larger than can be calculated with the usual unresolved - resonance treatment unless the average neutron and radiative-capture widths are correlated. It is shown that such an apparent correlation can arise as a result of multiple-scattering enhancement of radiative capture in the samples used, and it is concluded that the evidence for intermediate structure in the capture of neutrons by /sup 238/U is not yet firmly established.

Authors:: Moore, M S; Corvi, F; Mewissen, L; Poortmans, F

Publication Date:: Thu Jan 01 00:00:00 EST 1981

Research Org.:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

OSTI Identifier:: 5927566

Report Number(s):: LA-UR-81-2649; CONF-810957-3
ON: DE82000592; TRN: 82-001271

DOE Contract Number:: W-7405-ENG-36

Resource Type:: Conference

Resource Relation:: Conference: Joint IAEA/NEA consultants meeting on uranium and plutonium resonance parameters, Vienna, Austria, 28 Sep 1981

Country of Publication:: United States

Language:: English

Subject:: 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; NEUTRON REACTIONS; CAPTURE; URANIUM 238 TARGET; CROSS SECTIONS; ENERGY DEPENDENCE; FLUCTUATIONS; INTERMEDIATE STRUCTURE; KEV RANGE 10-100; P WAVES; PARITY; RESONANCE; S WAVES; TOTAL CROSS SECTIONS; BARYON REACTIONS; ENERGY RANGE; HADRON REACTIONS; KEV RANGE; NUCLEAR REACTIONS; NUCLEON REACTIONS; PARTIAL WAVES; PARTICLE PROPERTIES; TARGETS; VARIATIONS; 652025* - Nuclear Properties & Reactions, A=220 & above, Experimental- Nuclear Reactions & Scattering- (-1987)

Citation Formats


                    Moore, M S, Corvi, F, Mewissen, L, and Poortmans, F. parity assignment of the pronounced structure in the radiative capture of neutrons by /sup 238/U below 100 keV.  United States: N. p., 1981. 
        Web.

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                    Moore, M S, Corvi, F, Mewissen, L, & Poortmans, F. parity assignment of the pronounced structure in the radiative capture of neutrons by /sup 238/U below 100 keV.  United States.

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                    Moore, M S, Corvi, F, Mewissen, L, and Poortmans, F. 1981.  
        "parity assignment of the pronounced structure in the radiative capture of neutrons by /sup 238/U below 100 keV".  United States.  https://www.osti.gov/servlets/purl/5927566.

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@article{osti_5927566,

  title        = {parity assignment of the pronounced structure in the radiative capture of neutrons by /sup 238/U below 100 keV},

  author       = {Moore, M S and Corvi, F and Mewissen, L and Poortmans, F},

  abstractNote = {Some years ago, Perez and de Saussure reported evidence for intermediate structure in the radiative capture cross sections of /sup 238/U. More recently, these and additional data, obtained by a different experimental technique but which showed the same non-statistical behavior, were analyzed by Perez et al. Under the assumption that the structure could be attributed to doorway states in the p/sup 3/2/ neutron channel. The results of an experimental determination of the parity of the structure, using neutron capture-gamma ray spectroscopy are reported. Much of the structure below 50 keV appears to be due to s-wave interactions. The magnitude of the fluctuations is much larger than can be calculated with the usual unresolved - resonance treatment unless the average neutron and radiative-capture widths are correlated. It is shown that such an apparent correlation can arise as a result of multiple-scattering enhancement of radiative capture in the samples used, and it is concluded that the evidence for intermediate structure in the capture of neutrons by /sup 238/U is not yet firmly established.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/5927566},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Jan 01 00:00:00 EST 1981},

  month        = {Thu Jan 01 00:00:00 EST 1981}

}

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