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Title: Performance of the upgraded ultracold neutron source at Los Alamos National Laboratory and its implication for a possible neutron electric dipole moment experiment

Journal Article · · Physical Review C
 [1];  [2];  [2];  [3];  [1];  [4];  [1];  [5];  [1];  [6];  [7];  [8];  [1];  [1];  [1];  [1];  [1];  [2];  [1];  [9] more »;  [1];  [10];  [1];  [1];  [1];  [3] « less
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Indiana Univ., Bloomington, IN (United States)
  3. North Carolina State Univ., Raleigh, NC (United States)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); North Carolina State Univ., Raleigh, NC (United States)
  5. Virginia Polytechnic Institute and State University, Blacksburg, VA (United States)
  6. Institut Laue-Langevin, Grenoble (France)
  7. Yale Univ., New Haven, CT (United States)
  8. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Indiana Univ., Bloomington, IN (United States)
  9. Joint Institute of Nuclear Research, Dubna, Moscow Region (Russia)
  10. Univ. of Kentucky, Lexington, KY (United States)

We report the ultracold neutron (UCN) source at Los Alamos National Laboratory (LANL), which uses solid deuterium as the UCN converter and is driven by accelerator spallation neutrons, has been successfully operated for over 10 years, providing UCN to various experiments, as the first production UCN source based on the superthermal process. It has recently undergone a major upgrade. This paper describes the design and performance of the upgraded LANL UCN source. Measurements of the cold neutron spectrum and UCN density are presented and compared to Monte Carlo predictions. The source is shown to perform as modeled. The UCN density measured at the exit of the biological shield was 184(32) UCN / cm3, a fourfold increase from the highest previously reported. Finally, the polarized UCN density stored in an external chamber was measured to be 39(7) UCN / cm3, which is sufficient to perform an experiment to search for the nonzero neutron electric dipole moment with a one-standard-deviation sensitivity of σ(dn) = 3 × 10-27 e cm.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Laboratory Directed Research and Development (LDRD) Program
Grant/Contract Number:
AC52-06NA25396; FG02-97ER41042; 20140015DR; AC05-00OR22725
OSTI ID:
1422926
Alternate ID(s):
OSTI ID: 1418395; OSTI ID: 1481656
Report Number(s):
LA-UR-17-29313; PRVCAN; TRN: US1801672
Journal Information:
Physical Review C, Vol. 97, Issue 1; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 38 works
Citation information provided by
Web of Science

References (36)

The neutron and its role in cosmology and particle physics journal October 2011
Experimental searches for the neutron electric dipole moment journal September 2009
Microscopic model for the neutron dynamic structure factor of solid methane in phase II
  • Shin, Yunchang; Mike Snow, W.; Liu, C. Y.
  • 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.2010.03.109
journal August 2010
Electroweak baryogenesis journal December 2012
Demonstration of a solid deuterium source of ultra-cold neutrons journal July 2004
First production of ultracold neutrons with a solid deuterium source at the pulsed reactor TRIGA Mainz⋆ journal November 2007
Measurement of the neutron β -asymmetry parameter A 0 with ultracold neutrons journal November 2012
Precision measurement of the neutron β -decay asymmetry journal March 2013
New search for the neutron electric dipole moment with ultracold neutrons at ILL journal November 2015
Super-thermal sources of ultra-cold neutrons journal June 1975
Improved Determination of the Neutron Lifetime journal November 2013
First Measurement of the Neutron β Asymmetry with Ultracold Neutrons journal January 2009
Realization of a gravity-resonance-spectroscopy technique journal April 2011
Neutron scattering kernel for solid deuterium journal June 2009
New scattering kernels for some materials of interest as advanced cold neutron moderators journal November 2006
Beta decay measurements with ultracold neutrons: a review of recent measurements and the research program at Los Alamos National Laboratory journal October 2014
The interaction of Ultra-Cold Neutrons (UCN) with liquid helium and a superthermal UCN source journal September 1977
Measurements of Ultracold-Neutron Lifetimes in Solid Deuterium journal December 2002
Performance of the Los Alamos National Laboratory spallation-driven solid-deuterium ultra-cold neutron source journal January 2013
Improved Experimental Limit on the Electric Dipole Moment of the Neutron journal September 2006
Electric dipole moments as probes of new physics journal July 2005
A thin film source of ultra-cold neutrons journal June 1986
Understanding of ultra-cold–neutron production in solid deuterium journal December 2010
Revised experimental upper limit on the electric dipole moment of the neutron journal November 2015
MSSM baryogenesis and electric dipole moments: an update on the phenomenology journal January 2010
Neutron lifetime measurements using gravitationally trapped ultracold neutrons journal September 2008
Determination of the Weak Axial Vector Coupling λ = g A / g V from a Measurement of the β -Asymmetry Parameter A in Neutron Beta Decay journal April 2013
CP Violation Without Strangeness book January 1997
Electric dipole moments of nucleons, nuclei, and atoms: The Standard Model and beyond journal July 2013
Evaluation of commercial nickel–phosphorus coating for ultracold neutron guides using a pinhole bottling method
  • Pattie, R. W.; Adamek, E. R.; Brenner, T.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 872 https://doi.org/10.1016/j.nima.2017.07.051
journal November 2017
Beta decays and non-standard interactions in the LHC era journal July 2013
New type of low temperature source of Ultra-cold neutrons and production of continous beams of UCN journal June 1983
Toward a new polyethylene scattering law determined using inelastic neutron scattering
  • Lavelle, C. M.; Liu, C. -Y.; Stone, M. B.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 711 https://doi.org/10.1016/j.nima.2013.01.048
journal May 2013
Detection system for neutron β decay correlations in the UCNB and Nab experiments
  • Broussard, L. J.; Zeck, B. A.; Adamek, E. R.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 849 https://doi.org/10.1016/j.nima.2016.12.030
journal March 2017
A new source of cold and ultracold neutrons journal June 1986
Determination of the Axial-Vector Weak Coupling Constant with Ultracold Neutrons journal October 2010

Cited By (7)

Final results for the neutron β -asymmetry parameter A 0 from the UCNA experiment journal January 2019
A next-generation inverse-geometry spallation-driven ultracold neutron source journal December 2019
Axionlike dark matter search using the storage ring EDM method journal April 2019
Measurement of the neutron lifetime using a magneto-gravitational trap and in situ detection journal May 2018
CP Violation in Higgs-Gauge Interactions: From Tabletop Experiments to the LHC text January 2019
Axion dark matter search using the storage ring EDM method text January 2017
A next-generation inverse-geometry spallation-driven ultracold neutron source text January 2019

Figures / Tables (6)


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