Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

K. B. Grammer, Ricardo Alarcon, L. Barrón-Palos, D. Blyth, J. D. Bowman, J. Calarco, C. Crawford, K. Craycraft, D. Evans, N. Fomin, J. Fry, M. Gericke, R. C. Gillis, G. L. Greene, J. Hamblen, C. Hayes, S. Kucuker, R. Mahurin, M. Maldonado-Velázquez, E. MartinM. McCrea, P. E. Mueller, M. Musgrave, H. Nann, S. I. Penttilä, W. M. Snow, Z. Tang, W. S. Wilburn

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσdΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also 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. We describe our measurements and compare them with previous work.

Original languageEnglish (US)
Article number180301
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume91
Issue number18
DOIs
StatePublished - May 8 2015

Fingerprint

thermal neutrons
scattering cross sections
Neutrons
Scattering
neutrons
Liquids
liquids
Hydrogen
liquid hydrogen
Neutron sources
cross sections
neutron sources
neutron cross sections
moderators
Moderators
spallation
hydrogen
Neutron scattering
energy
ridges

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission. / Grammer, K. B.; Alarcon, Ricardo; Barrón-Palos, L.; Blyth, D.; Bowman, J. D.; Calarco, J.; Crawford, C.; Craycraft, K.; Evans, D.; Fomin, N.; Fry, J.; Gericke, M.; Gillis, R. C.; Greene, G. L.; Hamblen, J.; Hayes, C.; Kucuker, S.; Mahurin, R.; Maldonado-Velázquez, M.; Martin, E.; McCrea, M.; Mueller, P. E.; Musgrave, M.; Nann, H.; Penttilä, S. I.; Snow, W. M.; Tang, Z.; Wilburn, W. S.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 91, No. 18, 180301, 08.05.2015.

Research output: Contribution to journalArticle

Grammer, KB, Alarcon, R, Barrón-Palos, L, Blyth, D, Bowman, JD, Calarco, J, Crawford, C, Craycraft, K, Evans, D, Fomin, N, Fry, J, Gericke, M, Gillis, RC, Greene, GL, Hamblen, J, Hayes, C, Kucuker, S, Mahurin, R, Maldonado-Velázquez, M, Martin, E, McCrea, M, Mueller, PE, Musgrave, M, Nann, H, Penttilä, SI, Snow, WM, Tang, Z & Wilburn, WS 2015, 'Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission', Physical Review B - Condensed Matter and Materials Physics, vol. 91, no. 18, 180301. https://doi.org/10.1103/PhysRevB.91.180301
Grammer, K. B. ; Alarcon, Ricardo ; Barrón-Palos, L. ; Blyth, D. ; Bowman, J. D. ; Calarco, J. ; Crawford, C. ; Craycraft, K. ; Evans, D. ; Fomin, N. ; Fry, J. ; Gericke, M. ; Gillis, R. C. ; Greene, G. L. ; Hamblen, J. ; Hayes, C. ; Kucuker, S. ; Mahurin, R. ; Maldonado-Velázquez, M. ; Martin, E. ; McCrea, M. ; Mueller, P. E. ; Musgrave, M. ; Nann, H. ; Penttilä, S. I. ; Snow, W. M. ; Tang, Z. ; Wilburn, W. S. / Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission. In: Physical Review B - Condensed Matter and Materials Physics. 2015 ; Vol. 91, No. 18.
@article{c6aba39324c743a2b2ad3bc41444bc1e,
title = "Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission",
abstract = "Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσdΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also 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. We describe our measurements and compare them with previous work.",
author = "Grammer, {K. B.} and Ricardo Alarcon and L. Barr{\'o}n-Palos and D. Blyth and Bowman, {J. D.} and J. Calarco and C. Crawford and K. Craycraft and D. Evans and N. Fomin and J. Fry and M. Gericke and Gillis, {R. C.} and Greene, {G. L.} and J. Hamblen and C. Hayes and S. Kucuker and R. Mahurin and M. Maldonado-Vel{\'a}zquez and E. Martin and M. McCrea and Mueller, {P. E.} and M. Musgrave and H. Nann and Penttil{\"a}, {S. I.} and Snow, {W. M.} and Z. Tang and Wilburn, {W. S.}",
year = "2015",
month = "5",
day = "8",
doi = "10.1103/PhysRevB.91.180301",
language = "English (US)",
volume = "91",
journal = "Physical Review B-Condensed Matter",
issn = "0163-1829",
publisher = "American Institute of Physics Publising LLC",
number = "18",

}

TY - JOUR

T1 - Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

AU - Grammer, K. B.

AU - Alarcon, Ricardo

AU - Barrón-Palos, L.

AU - Blyth, D.

AU - Bowman, J. D.

AU - Calarco, J.

AU - Crawford, C.

AU - Craycraft, K.

AU - Evans, D.

AU - Fomin, N.

AU - Fry, J.

AU - Gericke, M.

AU - Gillis, R. C.

AU - Greene, G. L.

AU - Hamblen, J.

AU - Hayes, C.

AU - Kucuker, S.

AU - Mahurin, R.

AU - Maldonado-Velázquez, M.

AU - Martin, E.

AU - McCrea, M.

AU - Mueller, P. E.

AU - Musgrave, M.

AU - Nann, H.

AU - Penttilä, S. I.

AU - Snow, W. M.

AU - Tang, Z.

AU - Wilburn, W. S.

PY - 2015/5/8

Y1 - 2015/5/8

N2 - Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσdΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also 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. We describe our measurements and compare them with previous work.

AB - Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσdΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also 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. We describe our measurements and compare them with previous work.

UR - http://www.scopus.com/inward/record.url?scp=84929603681&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84929603681&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.91.180301

DO - 10.1103/PhysRevB.91.180301

M3 - Article

AN - SCOPUS:84929603681

VL - 91

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 0163-1829

IS - 18

M1 - 180301

ER -