Improved branching ratio measurement for the decay K(0)(L) --> &mgr;(+)&mgr;(-)
We report results from Experiment 871, performed at the BNL AGS, of a measurement of the branching ratio K(0)(L)-->&mgr;(+)&mgr;(-) with respect to the CP-violating mode K(0)(L)-->pi(+)pi(-). This experiment detected over 6200 candidate &mgr;(+)&mgr;(-) events, a factor of 6 more than that seen in all previous measurements combined. The resulting branching ratio gamma(K(0)(L)-->&mgr;(+)&mgr;(-))/gamma(K(0)(L)-->pi(+)pi(-)) = (3. 474+/-0.057)x10(-6) leads to a branching fraction B(K(0)(L)-->&mgr;(+)&mgr;(-)) = (7.18+/-0.17)x10(-9), which is consistent with the current world average, and reduces the uncertainty in this decay mode by a factor of 3.
Ambrose
D
University of Texas, Austin, Texas 78712, USA.
Arroyo
C
Bachman
M
Connor
D
Eckhause
M
Graessle
S
Hancock
AD
Hartman
K
Hebert
M
Hoff
CH
Hoffmann
GW
Irwin
GM
Kane
JR
Kanematsu
N
Kuang
Y
Lang
K
Lee
R
Martin
RD
McDonough
J
Milder
A
Molzon
WR
Pommot-Maia
M
Riley
PJ
Ritchie
JL
Rubin
PD
Vassilakopoulos
VI