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Title: NPDGamma: A Measurement of the Parity-Violating Gamma Asymmetry A in n-p Capture

Abstract

The NPDGamma Experiment measures the parity-violating correlation A{sub {Gamma}Y} between neutron spin and photon momentum in the reaction {rvec n} + p {yields} d + {gamma}. Knowledge of A{sub {Gamma}Y} and other parity-violating observables in few-body nuclear systems will provide constraints for a parameterized description of {Delta}S = 0 parity-violating phenomena free from complications of nuclear structure. The NPDGamma experiment uses a polarized cold pulsed neutron beam, a liquid parahydrogen target, and a cylindrical array of 48 CsI(Tl) scintillation detectors operated in current mode to search for the asymmetry. NPDGamma recently completed the first phase of the program to measure A{sub {Gamma}Y} at the Los Alamos Neutron Science Center with the preliminary result A{sub {Gamma}Y} = (-1.2 {+-} 2.1(stat.) {+-} 0.1(sys.)) x 10{sup -7}, reproducing the previous upper limit from a measurement at a reactor facility. We discuss the theoretical background and experimental method and report on preliminary analysis of the LANSCE data. The second phase of the program to measure A{sub {Gamma}Y} is in progress at the Spallation Neutron Source at Oak Ridge National Laboratory.

Authors:
 [1];  [2];  [2];  [3];  [4];  [5];  [1];  [6];  [7];  [5];  [8];  [9];  [10];  [11];  [12];  [13];  [8];  [14];  [15];  [16] more »;  [1];  [1];  [17];  [14];  [1];  [18];  [14];  [1];  [12];  [19];  [20];  [21];  [1];  [6];  [22];  [23];  [24];  [1];  [21];  [21] « less
  1. Indiana University
  2. Arizona State University
  3. Arizona State University & Univ. Nacional Autonoma de Mexico
  4. ORNL
  5. Thomas Jefferson National Accelerator Facility
  6. University of Michigan
  7. University of Kentucky, Lexington
  8. University of New Hampshire
  9. University of Tennessee, Knoxville (UTK)
  10. University of California, Berkeley
  11. National Institute of Standards and Technology (NIST), Gaithersburg, MD
  12. University of Manitoba, Canada
  13. University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)
  14. High Energy Accelerator Research Organization, KEK
  15. Hamilton College, New York
  16. Paul Scherrer Institut, Villigen, Switzerland
  17. University of Manitoba & Thomas Jefferson National Accelerator Facility
  18. University of California, Davis
  19. Oak Ridge National Laboratory (ORNL)
  20. TRIUMF, Canada
  21. Los Alamos National Laboratory (LANL)
  22. North Carolina State University
  23. Joint Institute for Nuclear Research, Dubna, Russia
  24. University of Dayton, Ohio
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1017365
DOE Contract Number:  
DE-AC05-00OR22725
Resource Type:
Journal Article
Journal Name:
Journal of Physics Conference Series
Additional Journal Information:
Journal Volume: 239; Journal Issue: 1; Journal ID: ISSN 1742--6596
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; NEUTRON BEAMS; NEUTRON SOURCES; NEUTRONS; NUCLEAR PHYSICS; NUCLEAR STRUCTURE; ORNL; PHOTONS; SCINTILLATION COUNTERS; SPALLATION; SPIN

Citation Formats

Gillis, R. C., Alarcon, R., Balascuta, S., Barron-Palos, L., Bowman, James D, Carlini, R. D., Chen, W., Chupp, T. E., Crawford, C., Covrig, S., Dabaghyan, M., Fomin, N., Freedman, S., Gentile, T. R., Gericke, M. T., Greene, G., Hersman, F. W., Ino, T., Jones, G., Lauss, B., Leuschner, M., Lozowski, W. R., Mahurin, R., Masuda, Y., Mei, J., Mitchell, G. S., Muto, S., Nann, H., Page, S. A., Penttila, Seppo, Ramsay, W. D., Salas-Bacci, A., Santra, S., Sharma, M., Seo, P. -N., Sharapov, E. I., Smith, T. B., Snow, W. M., Wilburn, W. S., and Yuan, V. NPDGamma: A Measurement of the Parity-Violating Gamma Asymmetry A in n-p Capture. United States: N. p., 2010. Web. doi:10.1088/1742-6596/239/1/012012.
Gillis, R. C., Alarcon, R., Balascuta, S., Barron-Palos, L., Bowman, James D, Carlini, R. D., Chen, W., Chupp, T. E., Crawford, C., Covrig, S., Dabaghyan, M., Fomin, N., Freedman, S., Gentile, T. R., Gericke, M. T., Greene, G., Hersman, F. W., Ino, T., Jones, G., Lauss, B., Leuschner, M., Lozowski, W. R., Mahurin, R., Masuda, Y., Mei, J., Mitchell, G. S., Muto, S., Nann, H., Page, S. A., Penttila, Seppo, Ramsay, W. D., Salas-Bacci, A., Santra, S., Sharma, M., Seo, P. -N., Sharapov, E. I., Smith, T. B., Snow, W. M., Wilburn, W. S., & Yuan, V. NPDGamma: A Measurement of the Parity-Violating Gamma Asymmetry A in n-p Capture. United States. https://doi.org/10.1088/1742-6596/239/1/012012
Gillis, R. C., Alarcon, R., Balascuta, S., Barron-Palos, L., Bowman, James D, Carlini, R. D., Chen, W., Chupp, T. E., Crawford, C., Covrig, S., Dabaghyan, M., Fomin, N., Freedman, S., Gentile, T. R., Gericke, M. T., Greene, G., Hersman, F. W., Ino, T., Jones, G., Lauss, B., Leuschner, M., Lozowski, W. R., Mahurin, R., Masuda, Y., Mei, J., Mitchell, G. S., Muto, S., Nann, H., Page, S. A., Penttila, Seppo, Ramsay, W. D., Salas-Bacci, A., Santra, S., Sharma, M., Seo, P. -N., Sharapov, E. I., Smith, T. B., Snow, W. M., Wilburn, W. S., and Yuan, V. Fri . "NPDGamma: A Measurement of the Parity-Violating Gamma Asymmetry A in n-p Capture". United States. https://doi.org/10.1088/1742-6596/239/1/012012.
@article{osti_1017365,
title = {NPDGamma: A Measurement of the Parity-Violating Gamma Asymmetry A in n-p Capture},
author = {Gillis, R. C. and Alarcon, R. and Balascuta, S. and Barron-Palos, L. and Bowman, James D and Carlini, R. D. and Chen, W. and Chupp, T. E. and Crawford, C. and Covrig, S. and Dabaghyan, M. and Fomin, N. and Freedman, S. and Gentile, T. R. and Gericke, M. T. and Greene, G. and Hersman, F. W. and Ino, T. and Jones, G. and Lauss, B. and Leuschner, M. and Lozowski, W. R. and Mahurin, R. and Masuda, Y. and Mei, J. and Mitchell, G. S. and Muto, S. and Nann, H. and Page, S. A. and Penttila, Seppo and Ramsay, W. D. and Salas-Bacci, A. and Santra, S. and Sharma, M. and Seo, P. -N. and Sharapov, E. I. and Smith, T. B. and Snow, W. M. and Wilburn, W. S. and Yuan, V.},
abstractNote = {The NPDGamma Experiment measures the parity-violating correlation A{sub {Gamma}Y} between neutron spin and photon momentum in the reaction {rvec n} + p {yields} d + {gamma}. Knowledge of A{sub {Gamma}Y} and other parity-violating observables in few-body nuclear systems will provide constraints for a parameterized description of {Delta}S = 0 parity-violating phenomena free from complications of nuclear structure. The NPDGamma experiment uses a polarized cold pulsed neutron beam, a liquid parahydrogen target, and a cylindrical array of 48 CsI(Tl) scintillation detectors operated in current mode to search for the asymmetry. NPDGamma recently completed the first phase of the program to measure A{sub {Gamma}Y} at the Los Alamos Neutron Science Center with the preliminary result A{sub {Gamma}Y} = (-1.2 {+-} 2.1(stat.) {+-} 0.1(sys.)) x 10{sup -7}, reproducing the previous upper limit from a measurement at a reactor facility. We discuss the theoretical background and experimental method and report on preliminary analysis of the LANSCE data. The second phase of the program to measure A{sub {Gamma}Y} is in progress at the Spallation Neutron Source at Oak Ridge National Laboratory.},
doi = {10.1088/1742-6596/239/1/012012},
url = {https://www.osti.gov/biblio/1017365}, journal = {Journal of Physics Conference Series},
issn = {1742--6596},
number = 1,
volume = 239,
place = {United States},
year = {2010},
month = {1}
}