Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission
- Univ. of Tennessee, Knoxville, TN (United States)
- Arizona State Univ., Tempe, AZ (United States)
- Univ. Nacional Autonoma de Mexico (Mexico)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Univ. of New Hampshire, Durham, NH (United States)
- Univ. of Kentucky, Lexington, KY (United States)
- Univ. of Tennessee, Knoxville, TN (United States); Univ. of Kentucky, Lexington, KY (United States)
- Univ. of Virginia, Charlottesville, VA (United States)
- Indiana Univ., Bloomington, IN (United States)
- Univ. of Manitoba, Winnipeg (Canada)
- Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Univ. of Tennessee-Chattanooga, Chattanooga, TN (United States)
- Middle Tennessee State Univ., Murfreesboro, TN (United States); Univ. of Manitoba, Winnipeg (Canada)
- Indiana Univ., Bloomington, IN (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
The scattering of slow neutron beams provides unique, non-destructive, quantitative information on the structure and dynamics of materials of interest in physics, chemistry, materials science, biology, geology, and other fields. Liquid hydrogen is a widely-used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. In particular the rapid drop of the slow neutron scattering cross section of liquid parahydrogen below 15 meV, which renders the moderator volume transparent to the neutron energies of most interest for scattering studies, is therefore especially interesting and important. We have placed an upper bound on the total cross section and the scattering cross section for slow neutrons with energies between 0.43 meV and 16.1 meV on liquid hydrogen at 15.6 K using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. At 1 meV this new upper bound is a factor of 3 below the data from previous work which has been used in the design of liquid hydrogen moderators at slow neutron sources. We describe our measurements, compare them with previous work, and discuss the implications for designing more intense slow neutron sources.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
- Sponsoring Organization:
- USDOE Office of Science (SC), Nuclear Physics (NP)
- Grant/Contract Number:
- FG02-03ER41258; PHY1068712; PHY1205833; IN111913; AC52-06NA25396; AC05-00OR22725; PHY-1068712; PHY-1205833
- OSTI ID:
- 1234661
- Alternate ID(s):
- OSTI ID: 1179193; OSTI ID: 1286791
- Report Number(s):
- LA-UR-14-27825; PRBMDO
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 91, Issue 18; ISSN 1098-0121
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Cryostat for the provision of liquid hydrogen with a variable ortho-para ratio for a low-dimensional cold neutron moderator
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text | January 2020 |
Optimization of moderators and beam extraction at the ESS
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journal | March 2018 |
Cryostat for the provision of liquid hydrogen with a variable ortho-para ratio for a low-dimensional cold neutron moderator
|
journal | January 2020 |
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