Recent results on CP-violation from Fermilab experiment E731

Conference · Sat Dec 01 04:00:00 EST 1990

OSTI ID:6030749

Hsiung, Yee B

We report the current status of the analysis for the CP-violation parameters, {var epsilon}{prime}/{var epsilon}, from the entire data sample of Fermilab experiment E731. A new measurement of the CP-violation parameter {eta}{sub {plus minus}{gamma}} was extracted from the K{sub L} {minus} K{sub S} interference of the {pi}{sup +}{pi}{sup {minus}}{gamma} decay mode downstream of a regenerator. The preliminary result, {vert bar}{eta}{sub {plus minus}{gamma}}{vert bar} = 0.0020 {plus minus} 0.0002(stat) {plus minus} 0.0003(syst), is consistent with {vert bar}{eta}{sub {plus minus}}{vert bar} from {pi}{sup +}{pi}{sup {minus}} decay mode. Some results on the measurements of the branching ratio for K{sub L} {yields} {pi}{sup +}{pi}{sup {minus}}{gamma} and K{sub S} {yields} {pi}{sup +}{pi}{sup {minus}}{gamma} are presented here. For the very first time, the quadratic decay parameter of K{sub L} {yields} 3{pi}{sup 0} has been measured from the 3{pi}{sup 0} Dalitz plot. Our result, b = ({minus}0.6 {plus minus} 1.4) {times} 10{sup {minus}3}, is consistent with zero, indicating a flat Dalitz distribution. It is inconsistent with the fitted result, b = ({minus}8.3 {plus minus} 2.4) {times} 10{sup {minus}3}, from Devlin and Dickey's review. 13 refs., 5 figs.

• Research Organization: Fermi National Accelerator Lab., Batavia, IL (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 6030749
• Report Number(s): FNAL/C-90/268; CONF-900822--27; ON: DE91007549
• Country of Publication: United States
• Language: English

Related Subjects

645102* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Weak Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BOSONS
BRANCHING RATIO
CP INVARIANCE
DATA
DECAY
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
HADRONS
INFORMATION
INVARIANCE PRINCIPLES
KAONS
MASS SPECTRA
MESONS
NUMERICAL DATA
PARTICLE DECAY
PSEUDOSCALAR MESONS
SPECTRA
STRANGE MESONS
STRANGE PARTICLES
WEAK PARTICLE DECAY