B r arrow. pi. nu. nu. ,. rho. nu. nu. and determination of t bar V sub t d / V sub u b t bar

Journal Article · Mon Jul 01 00:00:00 EDT 1991 · Physical Review, D (Particles Fields); (USA)

DOI:https://doi.org/10.1103/PhysRevD.44.291· OSTI ID:5538382

Schwartz, A ^[1]; Deshpande, N G ^[2]; Urheim, J ^[3]

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1. Department of Physics, Stanford University, Stanford, California 94305-4060 (USA)
2. Institute of Theoretical Science, University of Oregon, Eugene, Oregon 97403 (USA)
3. Department of Physics, California Institute of Technology, Pasadena, California 91125 (USA)

The rare decays {ital B}{r arrow}{pi}{nu}{bar {nu}} and {ital B}{r arrow}{rho}{nu}{bar {nu}} are investigated. The ratio of branching fractions {ital B}({ital B}{r arrow}{ital M}{nu}{bar {nu}})/{ital B}({ital B}{r arrow}{ital Ml}{bar {nu}}) is shown to depend on the ratio {vert bar}{ital V}{sub {ital t}{ital d}}/{ital V}{sub {ital u}{ital b}}{vert bar} of Kobayashi-Maskawa matrix elements with little hadronic uncertainty. The measurement of these fractions thus gives a robust constraint on the Kobayashi-Maskawa matrix. The branching fractions for {ital B}{r arrow}{pi}{nu}{bar {nu}}, {rho}{nu}{bar {nu}} are estimated to range from 10{sup {minus}8} to 10{sup {minus}6}; an experimental method is presented which yields a single-event sensitivity below 10{sup {minus}4}.

• OSTI ID: 5538382
• Journal Information: Physical Review, D (Particles Fields); (USA), Vol. 44:1; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTINEUTRINOS
PARTICLE PRODUCTION
B MESONS
SEMILEPTONIC DECAY
NEUTRINOS
PIONS
BRANCHING RATIO
FORM FACTORS
ISOSPIN
KOBAYASHI-MASKAWA MATRIX
LAGRANGIAN FUNCTION
MATRIX ELEMENTS
MONTE CARLO METHOD
STANDARD MODEL
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
BEAUTY PARTICLES
BOSONS
DECAY
ELEMENTARY PARTICLES
FERMIONS
FIELD THEORIES
FUNCTIONS
HADRONS
LEPTONS
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MATHEMATICAL MODELS
MATRICES
MATTER
MESONS
PARTICLE DECAY
PARTICLE MODELS
PARTICLE PROPERTIES
PSEUDOSCALAR MESONS
UNIFIED GAUGE MODELS
UNIFIED-FIELD THEORIES
WEAK PARTICLE DECAY
645203* - High Energy Physics- Particle Interactions & Properties-Theoretical- Weak Interactions & Properties