A search for effective strangeness-changing neutral currents in K sub L sup 0 decays

Miscellaneous · Sun Jan 01 00:00:00 EST 1989

OSTI ID:5246624

Mannelli, E B.M.

Results from AGS (Alternating Gradient Synchroton) experiment {number sign} 780 at Brookhaven National Laboratory are reported for the decay modes, K{sub L}{sup 0} {yields} {mu}{sup +} + {mu}{sup {minus}} and K{sub L}{sup 0} {yields} {pi}{sup 0} + e{sup +} + e{sup {minus}}. The detector consisted of a charged particle spectrometer of four mini-drift chambers, two upstream and two downstream of an analyzing magnet, a hydrogen Cherenkov counter and lead glass array for electron identification, and a muon filter and range stack consisting of a series of iron slabs followed by arrays of scintillator counters. Several additional counter arrays provided trigger level particle identification and event topology. Di-lepton triggers were accepted for {mu} + e, e + e and {mu} + {mu}. Two charged pion triggers were accepted for normalization to the Cp violating decay K{sub L}{sup 0} {yields} {pi}{sup +} + {pi}{sup {minus}}, and to K{sub L}{sup 0} {yields} {pi}{sup 0} + {pi}{sup +} + {pi}{sup {minus}}. Two events consistent with the decay K{sub L}{sup 0} {yields} {mu}{sup +} + {mu}{sup {minus}} were observed with a single event sensitivity of 4.6 {times} 10{sup {minus}9}. This result is consistent with the established branching ratio of (9.1 {plus minus} 1.9) {times} 10{sup {minus}9}. While the sensitivity achieved in experiment {number sign} 780 did not allow for an improved measurement of this decay mode, the result is important as a check of the sensitivity established using the K{sub L}{sup 0} {yields} {pi}{sup +} + {pi}{sup {minus}} decays. One event consistent with K{sub L}{sup 0} {yields} {pi}{sup 0} + e{sup +} + e{sup {minus}} was observed with a single event sensitivity of 2 {times} 10{sup {minus}7} for the observed lepton pair mass of 328 MeV/c{sup 2}.

• Research Organization: Yale Univ., New Haven, CT (United States)
• OSTI ID: 5246624
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
KAONS NEUTRAL LONG-LIVED
WEAK PARTICLE DECAY
BRANCHING RATIO
BROOKHAVEN AGS
CHERENKOV COUNTERS
CP INVARIANCE
DRIFT CHAMBERS
ELECTRONS
MUONS
PARTICLE IDENTIFICATION
PIONS NEUTRAL
POSITRONS
SCINTILLATION COUNTERS
SPECTROMETERS
ACCELERATORS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
BOSONS
CYCLIC ACCELERATORS
DECAY
ELEMENTARY PARTICLES
FERMIONS
HADRONS
INVARIANCE PRINCIPLES
KAONS
KAONS NEUTRAL
LEPTONS
MATTER
MEASURING INSTRUMENTS
MESONS
MULTIWIRE PROPORTIONAL CHAMBERS
PARTICLE DECAY
PIONS
PROPORTIONAL COUNTERS
PSEUDOSCALAR MESONS
RADIATION DETECTORS
STRANGE MESONS
STRANGE PARTICLES
SYNCHROTRONS
645102* - High Energy Physics- Particle Interactions & Properties-Experimental- Weak Interactions & Properties