Search for direct CP violation in K/sup 0/ decays by a measurement of epsilon'

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5496175

Black, J K

The CP violation parameter epsilon' has been measured at the Brookhaven AGS in an attempt to observe a deviation from zero in the value of this parameter. Such a deviation would indicate the presence of absolute value of ..delta..S = 1 CP violating amplitudes absent in superweak models of CP violation but generally present in gauge theory realizations of CP non-conservation. Two pion decays of neutral kaons were observed in a detector consisting of scintillation counters and proportional wire chambers arranged about a spectrometer magnet and a large, finely segmented lead glass array. The detector was situated around a 0/sup 0/ neutral beam line equipped with a carbon K/sub S/ regenerator which could be remotely moved in and out of the beam. Charged and neutral decays were observed simultaneously under two beam conditions: from an almost pure K/sub L/ beam (regenerator removed) and from a beam composed largely of K/sub S/ mesons (regenerator in the beam). Over 500 of the difficult K/sub L/ ..-->.. ..pi../sup 0/..pi../sup 0/ events were collected giving a measured value of epsilon'/epsilon = 0.015 +/- 0.018, consistent with the best previous measurement of epsilon'/epsilon = 0.00 +/- 0.02. This result places serious constraints of Higgs exchange models of CP violation which generally predict absolute value of epsilon'/epsilon greater than or equal to 0.02.

• Research Organization: Yale Univ., New Haven, CT (USA)
• OSTI ID: 5496175
• Country of Publication: United States
• Language: English

Related Subjects

645203* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Weak Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BOSONS
CP INVARIANCE
DATA
DECAY
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
HADRONS
HIGGS BOSONS
INFORMATION
INVARIANCE PRINCIPLES
KAONS
KAONS NEUTRAL
KAONS NEUTRAL LONG-LIVED
KAONS NEUTRAL SHORT-LIVED
MATHEMATICAL MODELS
MESONS
NUMERICAL DATA
PARTICLE DECAY
PARTICLE MODELS
PIONS
PIONS NEUTRAL
POSTULATED PARTICLES
PSEUDOSCALAR MESONS
STRANGE MESONS
STRANGE PARTICLES
UNIFIED GAUGE MODELS
WEAK HADRONIC DECAY
WEAK PARTICLE DECAY