Search for the flavor-changing neutral current decay K sup + yields. pi. sup +. nu. nu

Conference · Mon Jan 01 00:00:00 EST 1990

OSTI ID:7039654

Ito, M M ^[1]

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1. Princeton Univ., NJ (USA). Joseph Henry Labs.

The observation that flavor-changing neutral currents (FCNC) in weak decays are highly suppressed was first explained by Glashow, Iliopoulos and Maiani in 1970, and their idea has since become a cornerstone of the Standard Model. They proposed a model of the weak interaction that included a then new fourth quark and which, in a natural way, allowed the existence of a neutral vector boson without inducing FCNC's at tree level. Thus the couplings of the neutral intermediary{hor ellipsis}cause no embarrassment.'' In higher order through, decays like K {yields} {pi}l{bar l} can proceed. Measurements of such processes provide a detailed test of the Standard Model since definite predictions for their rates can be calculated. Conversely, if no contradictions are found and the standard model is assumed to describe the physics, measurements limit the allowed values of the parameters of the model. As is often the case in studying processes that are highly suppressed and heretofore unseen, improvements in the sensitivity of experiments allow the possibility for the discovery of new physics that exhibits a similar experimental signature. This paper describes experiment 787 at Brookhaven which is expected to address some of these issues. The status and future of the experiment will be described here. The main goal of E787 is to measure the rate of K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}} at the standard model level. In addition, the experiment has sensitivity to other FCNC decays of the charged kaon, in particular the decays K{sup +} {yields} {pi}{sup +}{mu}{sup +}{mu}{sup {minus}} and K{sup +} {yields} {pi}{sup +}{gamma}{gamma}.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 7039654
• Report Number(s): BNL-44763; CONF-900135-17; ON: DE90013747; TRN: 90-022311
• Resource Relation: Conference: 15. general meeting of the Division of Particles and Fields of the American Physical Society, Houston, TX (USA), 3-6 Jan 1990
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
KAONS PLUS
WEAK PARTICLE DECAY
BRANCHING RATIO
CHERENKOV COUNTERS
FLAVOR MODEL
KOBAYASHI-MASKAWA MATRIX
MEASURING METHODS
TRIGGER CIRCUITS
WEAK NEUTRAL CURRENTS
ALGEBRAIC CURRENTS
BOSONS
COMPOSITE MODELS
CURRENTS
DECAY
ELECTRONIC CIRCUITS
ELEMENTARY PARTICLES
FIELD THEORIES
HADRONS
KAONS
MATHEMATICAL MODELS
MATRICES
MEASURING INSTRUMENTS
MESONS
NEUTRAL CURRENTS
PARTICLE DECAY
PARTICLE MODELS
PSEUDOSCALAR MESONS
PULSE CIRCUITS
QUARK MODEL
RADIATION DETECTORS
STRANGE MESONS
STRANGE PARTICLES
UNIFIED-FIELD THEORIES
645102* - High Energy Physics- Particle Interactions & Properties-Experimental- Weak Interactions & Properties