Observation of CP violation in K(L)-->pi(+)pi(-)e(+)e(-) decays
We report the first observation of a manifestly CP violating effect in the K(L)-->pi(+)pi(-)e(+)e(-) decay mode. A large asymmetry was observed in the distribution of these decays in the CP-odd and T-odd angle straight phi between the decay planes of the e(+)e(-) and pi(+)pi(-) pairs in the K(L) center of mass system. After acceptance corrections, the overall asymmetry is found to be [13.6+/-2. 5(stat)+/-1.2(syst)]%. This is the largest CP-violating effect yet observed when integrating over the entire phase space of a mode and the first such effect observed in an angular variable.
Alavi-Harati
A
University of Wisconsin, Madison, Wisconsin 53706, USA.
Albuquerque
IF
Alexopoulos
T
Arenton
M
Arisaka
K
Averitte
S
Barker
AR
Bellantoni
L
Bellavance
A
Belz
J
Ben-David
R
Bergman
DR
Blucher
E
Bock
GJ
Bown
C
Bright
S
Cheu
E
Childress
S
Coleman
R
Corcoran
MD
Corti
G
Cox
B
Crisler
MB
Erwin
AR
Ford
R
Glazov
A