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Title: Measurement of the relative longitudinal spin-dependent total cross-section difference in n(vector sign)-d(vector sign) scattering

Abstract

We report relative measurements of the n(vector sign)-d(vector sign) longitudinal spin-dependent total cross-section difference ({delta}{sigma}{sub L}){sub d}, at E{sub n}(lab) = 5.0, 6.88, and 9.0 MeV. The deuteron target was polarized via dynamic nuclear polarization at 250 mK in a 2.5-T external magnetic field. The target polarization was monitored by nuclear magnetic resonance and was calibrated by a ({delta}{sigma}{sub L}){sub d} measurement at E{sub n}(lab) = 1.18 MeV. The polarized neutron beams were produced through the {sup 3}H(p(vector sign),n(vector sign)){sup 3}He and {sup 2}H(d(vector sign),n(vector sign)){sup 3}He reactions. The neutron polarizations were determined either by direct measurement or from known or calculated polarization-transfer coefficients. The results for ({delta}{sigma}{sub L}){sub d} show agreement with theoretical calculations based on nucleon-nucleon potential models but are not of sufficient precision to distinguish the presence or absence of three-nucleon force contributions to the cross sections.

Authors:
; ; ; ;  [1];  [2];  [1];  [2]
  1. Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708-0308 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20771319
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevC.73.034002; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; DEUTERIUM; DEUTERIUM TARGET; DEUTERON BEAMS; DEUTERON REACTIONS; HELIUM 3; MAGNETIC FIELDS; MEV RANGE; NEUTRON BEAMS; NEUTRON REACTIONS; NEUTRONS; NUCLEAR MAGNETIC RESONANCE; NUCLEON-NUCLEON POTENTIAL; POLARIZATION; POLARIZED BEAMS; SCATTERING; SPIN; TOTAL CROSS SECTIONS; TRITIUM

Citation Formats

Foster, R.D., Gould, C.R., Haase, D.G., Kelley, J.M., Markoff, D.M., Physics Department, North Carolina State University, Raleigh, North Carolina 27695-8202, Tornow, W., and Physics Department, Duke University, Durham, North Carolina 27708-0308. Measurement of the relative longitudinal spin-dependent total cross-section difference in n(vector sign)-d(vector sign) scattering. United States: N. p., 2006. Web. doi:10.1103/PhysRevC.73.034002.
Foster, R.D., Gould, C.R., Haase, D.G., Kelley, J.M., Markoff, D.M., Physics Department, North Carolina State University, Raleigh, North Carolina 27695-8202, Tornow, W., & Physics Department, Duke University, Durham, North Carolina 27708-0308. Measurement of the relative longitudinal spin-dependent total cross-section difference in n(vector sign)-d(vector sign) scattering. United States. doi:10.1103/PhysRevC.73.034002.
Foster, R.D., Gould, C.R., Haase, D.G., Kelley, J.M., Markoff, D.M., Physics Department, North Carolina State University, Raleigh, North Carolina 27695-8202, Tornow, W., and Physics Department, Duke University, Durham, North Carolina 27708-0308. Wed . "Measurement of the relative longitudinal spin-dependent total cross-section difference in n(vector sign)-d(vector sign) scattering". United States. doi:10.1103/PhysRevC.73.034002.
@article{osti_20771319,
title = {Measurement of the relative longitudinal spin-dependent total cross-section difference in n(vector sign)-d(vector sign) scattering},
author = {Foster, R.D. and Gould, C.R. and Haase, D.G. and Kelley, J.M. and Markoff, D.M. and Physics Department, North Carolina State University, Raleigh, North Carolina 27695-8202 and Tornow, W. and Physics Department, Duke University, Durham, North Carolina 27708-0308},
abstractNote = {We report relative measurements of the n(vector sign)-d(vector sign) longitudinal spin-dependent total cross-section difference ({delta}{sigma}{sub L}){sub d}, at E{sub n}(lab) = 5.0, 6.88, and 9.0 MeV. The deuteron target was polarized via dynamic nuclear polarization at 250 mK in a 2.5-T external magnetic field. The target polarization was monitored by nuclear magnetic resonance and was calibrated by a ({delta}{sigma}{sub L}){sub d} measurement at E{sub n}(lab) = 1.18 MeV. The polarized neutron beams were produced through the {sup 3}H(p(vector sign),n(vector sign)){sup 3}He and {sup 2}H(d(vector sign),n(vector sign)){sup 3}He reactions. The neutron polarizations were determined either by direct measurement or from known or calculated polarization-transfer coefficients. The results for ({delta}{sigma}{sub L}){sub d} show agreement with theoretical calculations based on nucleon-nucleon potential models but are not of sufficient precision to distinguish the presence or absence of three-nucleon force contributions to the cross sections.},
doi = {10.1103/PhysRevC.73.034002},
journal = {Physical Review. C, Nuclear Physics},
number = 3,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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