A measurement of the parity-violating gamma-ray asymmetry in the neutron-proton capture

Conference · Tue Jan 01 04:00:00 EST 2002

DOI:https://doi.org/10.1142/9789812795151_0077· OSTI ID:976399

Penttila, S I ^[1]; Bowman, J D ^[2]; Carlini, R D ^[3]; Case, T; Chupp, T E; Coulter, K P; Freedman, S J; Gentile, T R; Gericke, M T ^[4]; Greene, G L; Hersmann, B; Ishimoto, S; Jones, G L; Leuschner, M B; Masuda, Y; Mitchell, G S ^[5]; Morimoto, K; Nann, H; Page, S A; Ramsay, W D ; Sharapov, Ė I ^[6]; Smith, T B ^[7]; Snow, W M ^[8]; Wilburn, S W; Yuan, V W ^[9]

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1. Seppo I.
2. J. David
3. Roger D.
4. Michael T.
5. Gregory S.
6. Ėduard Ivanovich
7. Todd B.
8. William M.
9. Vincent W.

The {rvec n} + p {yields} d + {gamma} experiment under construction at LANSCE studies the weak interaction between neutrons and protons. The experiments will measure the directional dependence of the parity-violating {gamma}-ray asymmetry, A{sub {gamma}}, in the polarized cold neutron capture by para-hydrogen. The goal is to measure A{sub {gamma}} with uncertainty of 0.5 x 10{sup -8}, 10% of its predicted value. A{sub {gamma}} primarily isolates the {Delta}I = 1 component of the hadronic weak interaction and thus will determine the long-range weak pion-nucleon coupling constant H{sub {pi}}{sup 1}. The experiment is carefully designed for the LANSCE pulsed spallation neutron source to achieve the proposed statistical precision and to control systematic errors. We discuss the experiment and its status.

• Research Organization: Los Alamos National Laboratory
• Sponsoring Organization: DOE
• OSTI ID: 976399
• Report Number(s): LA-UR-02-6560
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACCURACY
ASYMMETRY
COLD NEUTRONS
CONSTRUCTION
COUPLING CONSTANTS
NEUTRON SOURCES
NEUTRONS
PROTONS
SPALLATION
SPECTROSCOPY
WEAK INTERACTIONS