skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Measurement of the absolute neutron beam polarization from a supermirror polarizer and the absolute efficiency of a neutron spin rotator for the NPDGamma experiment using a polarized 3He neutron spin-filter

Journal Article · · Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment
 [1];  [2];  [3];  [4];  [3];  [5];  [6];  [5];  [7];  [8];  [9];  [10];  [11];  [12];  [13];  [13];  [14];  [9];  [15];  [5] more »;  [9];  [11];  [5];  [5];  [16];  [7];  [17];  [13];  [18] « less
  1. Univ. of Tennessee, Knoxville, TN (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  2. Univ. of Virginia, Charlottesville, VA (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Arizona State Univ., Tempe, AZ (United States)
  4. National Autonomous Univ. of Mexico (UNAM), Mexico City (Mexico). Inst. of Physics
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  6. Univ. of Michigan, Ann Arbor, MI (United States)
  7. Univ. of Kentucky, Lexington, KY (United States)
  8. Univ. of Tennessee, Knoxville, TN (United States); Univ. of Kentucky, Lexington, KY (United States)
  9. Univ. of Tennessee, Knoxville, TN (United States)
  10. Univ. of Virginia, Charlottesville, VA (United States); Indiana Univ., Bloomington, IN (United States)
  11. Univ. of Manitoba, Winnipeg, MB (Canada)
  12. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Indiana Univ., Bloomington, IN (United States)
  13. Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  14. Univ. of Tennessee, Chattanooga, TN (United States)
  15. North Carolina State Univ., Raleigh, NC (United States)
  16. Indiana Univ., Bloomington, IN (United States)
  17. Indiana Univ., Bloomington, IN (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  18. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
+ Show Author Affiliations

Accurately measuring the neutron beam polarization of a high flux, large area neutron beam is necessary for many neutron physics experiments. The Fundamental Neutron Physics Beamline (FnPB) at the Spallation Neutron Source (SNS) is a pulsed neutron beam that was polarized with a supermirror polarizer for the NPDGamma experiment. The polarized neutron beam had a flux of ~109 neutrons per second per cm2 and a cross sectional area of 10 x 12 cm2. The polarization of this neutron beam and the efficiency of a RF neutron spin rotator installed downstream on this beam were measured by neutron transmission through a polarized 3He neutron spin-filter. The pulsed nature of the SNS enabled us to employ an absolute measurement technique for both quantities which does not depend on accurate knowledge of the phase space of the neutron beam or the 3He polarization in the spin filter and is therefore of interest for any experiments on slow neutron beams from pulsed neutron sources which require knowledge of the absolute value of the neutron polarization. The polarization and spin-reversal efficiency measured were done for the NPDGamma experiment, which measures the parity violating γ-ray angular distribution asymmetry with respect to the neutron spin direction in the capture of polarized neutrons on protons. Finally, the experimental technique, results, systematic effects, and applications to neutron capture targets are discussed.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Univ. of Kentucky, Lexington, KY (United States); Indiana Univ., Bloomington, IN (United States); Univ. of Virginia, Charlottesville, VA (United States); Univ. of Manitoba, Winnipeg, MB (Canada)
Sponsoring Organization:
USDOE Office of Science (SC). Nuclear Physics (NP) (SC-26); Natural Sciences and Engineering Council of Canada (NSERC); Canada Foundation for Innovation (CFI); USDOE Office of Science (SC), Nuclear Physics (NP); National Science Foundation (NSF); Natural Sciences and Engineering Research Council of Canada (NSERC)
Grant/Contract Number:
89233218CNA000001; AC05-00OR22725; FG02-03ER41258; SC0008107; SC0014622; PHY-1306942; PHY-1614545; NSF-0855610; NSF-1205833; SAPPJ 341289-2013
OSTI ID:
1483524
Alternate ID(s):
OSTI ID: 1479758; OSTI ID: 1548521
Report Number(s):
LA-UR-18-23163
Journal Information:
Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 895, Issue C; ISSN 0168-9002
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 10 works
Citation information provided by
Web of Science

References (19)

Unified treatment of the parity violating nuclear force journal February 1980
Lattice QCD calculation of nuclear parity violation journal February 2012
A measurement of the absolute neutron beam polarization produced by an optically pumped neutron spin filter
  • Rich, D. R.; Bowman, J. D.; Crawford, B. E.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 481, Issue 1-3 https://doi.org/10.1016/S0168-9002(01)01331-6
journal April 2002
A large area polarized 3He neutron spin filter
  • Chupp, T. E.; Coulter, K. P.; Kandes, M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 574, Issue 3 https://doi.org/10.1016/j.nima.2007.02.091
journal May 2007
Parity violation in neutron–proton capture—The NPDGamma experiment
  • Gericke, Michael; Page, S.; Ramsay, D.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 611, Issue 2-3 https://doi.org/10.1016/j.nima.2009.07.057
journal December 2009
Measurement of parity-violating γ -ray asymmetry in the capture of polarized cold neutrons on protons journal January 2011
Neutron Beam Effects on Spin-Exchange-Polarized He 3 journal August 2008
The Spallation Neutron Source in Oak Ridge: A powerful tool for materials research journal November 2006
Fundamental neutron physics beamline at the spallation neutron source at ORNL
  • Fomin, N.; Greene, G. L.; Allen, R. R.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 773 https://doi.org/10.1016/j.nima.2014.10.042
journal February 2015
A method for the accurate determination of the polarization of a neutron beam using a polarized 3He spin filter
  • Greene, G. L.; Thompson, A. K.; Dewey, M. S.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 356, Issue 2-3 https://doi.org/10.1016/0168-9002(94)01249-0
journal March 1995
Neutron interferometric measurement of the scattering length difference between the triplet and singlet states of n − He 3 journal December 2014
The implementation of a super mirror polarizer at the SNS fundamental neutron physics beamline
  • Balascuta, S.; Alarcon, R.; Baeβler, S.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 671 https://doi.org/10.1016/j.nima.2011.12.088
journal April 2012
High-efficiency resonant rf spin rotator with broad phase space acceptance for pulsed polarized cold neutron beams journal August 2008
A liquid parahydrogen target for the measurement of a parity-violating gamma asymmetry in
  • Santra, S.; Barrón Palos, L.; Blessinger, C.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 620, Issue 2-3 https://doi.org/10.1016/j.nima.2010.04.135
journal August 2010
Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission journal May 2015
Polarized 3He Neutron Spin Filters at Oak Ridge National Laboratory journal January 2013
McStas, a general software package for neutron ray-tracing simulations journal January 1999
3He neutron spin filter at ILL journal December 1997
Lattice QCD Calculation of Nuclear Parity Violation text January 2011

Figures / Tables (16)

Figure 1(p. 6)figure Figure 1
Figure 2(p. 7)figure Figure 2
Figure 3(p. 7)figure Figure 3
Figure 4(p. 8)figure Figure 4
Figure 5(p. 8)figure Figure 5
Figure 6(p. 8)figure Figure 6
Figure 7(p. 9)figure Figure 7
Figure 8(p. 9)figure Figure 8
Figure 10(p. 10)figure Figure 10
Figure 9(p. 10)figure Figure 9
Figure 11(p. 11)figure Figure 11
Table 1(p. 11)table Table 1
Figure 12(p. 12)figure Figure 12
Figure 13(p. 13)figure Figure 13
Table 2(p. 13)table Table 2
Table 3(p. 13)table Table 3

Similar Records

Precision Measurements with Low Energy Neutrons (Final Report)
Technical Report · Wed Apr 10 00:00:00 EDT 2019 · OSTI ID:1483524
Monte Carlo calculation and verification of the geometrical factors for the NPDGamma experiment
Journal Article · Sat Jun 30 00:00:00 EDT 2018 · Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment · OSTI ID:1483524
+5 more
A Liquid Parahydrogen Target for the Measurement of a Parity-violating Gamma Asymmetry in Polarized Neutron Capture on Protons
Journal Article · Sat May 01 00:00:00 EDT 2010 · Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment · OSTI ID:1483524

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
polarized neutrons
polarized 3He
polarimetry
spin-exchange optical pumping
NPDGamma