Interpretation of the neutron electric dipole moment: Possible relationship to t bar. epsilon. prime t bar

Journal Article · Mon Jan 01 04:00:00 EST 1990 · Physical Review, D (Particles Fields); (USA)

DOI:https://doi.org/10.1103/PhysRevD.41.177· OSTI ID:6965339

Booth, M J; Briere, R A; Sachs, R G ^[1]

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1. Enrico Fermi Institute and Physics Department, The University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637 (US)

Recent measurements of {ital D}{sub {ital n}} indicate that it {ital may} be of order {ital G}{sub {ital F}} (milliweak), which is much larger than predicted by the Kobayashi-Maskawa (KM) model. The predicted KM moment is shown to be small because it is of second order in {ital G}{sub {ital F}} (superweak) {ital and} suppressed by the Glashow-Iliopoulos-Maiani (GIM) mechanism. GIM cancellations have their largest effect on the calculation of the moment of a single quark so that {ital W}-exchange contributions between pairs of quarks dominate {ital D}{sub {ital n}} in the KM model. Experimental confirmation that {ital D}{sub {ital n}} is of order {ital G}{sub {ital F}} (in the range 10{sup {minus}27}--10{sup {minus}25} e cm) would require a {ital T}-violating phase between the {ital P}-conserving and {ital P}-violating first-order weak interactions, as occurs in the Weinberg model. Any such {ital T} violation would lead to a relationship between {epsilon}{prime} and {ital D}{sub {ital n}} of the form {vert bar}{ital D}{sub {ital n}}{vert bar}{similar to}{vert bar}{epsilon}{prime}{vert bar}. We estimate the ratio {vert bar}{ital D}{sub {ital n}}/{epsilon}{prime}{vert bar} for the Weinberg model, and show that it is consistent with current data on {ital D}{sub {ital n}}, {vert bar}{epsilon}{prime}/{epsilon}{vert bar}, and {vert bar}{epsilon}{vert bar}. However, the current data are also consistent with {ital D}{sub {ital n}}={epsilon}{prime}=0, so that a firm conclusion cannot be drawn now.

• DOE Contract Number: AC02-80ER10587
• OSTI ID: 6965339
• Journal Information: Physical Review, D (Particles Fields); (USA), Journal Name: Physical Review, D (Particles Fields); (USA) Vol. 41:1; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

645202* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Electromagnetic Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
COMPOSITE MODELS
CP INVARIANCE
DIPOLE MOMENTS
ELECTRIC DIPOLE MOMENTS
ELECTRIC MOMENTS
ELEMENTARY PARTICLES
FERMIONS
FIELD THEORIES
HADRONS
INVARIANCE PRINCIPLES
KOBAYASHI-MASKAWA MATRIX
MATHEMATICAL MODELS
MATRICES
NEUTRONS
NUCLEONS
P INVARIANCE
PARTICLE MODELS
QUARK MODEL
T INVARIANCE
UNIFIED GAUGE MODELS
UNIFIED-FIELD THEORIES
WEINBERG-SALAM GAUGE MODEL