Improved measurement of the K+-->pi+nunu; branching ratio.
An additional event near the upper kinematic limit for K+-->pi(+)nunu; has been observed by experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+-->pi(+)nunu;)=(1.47(+1.30)(-0.89))x10(-10) based on three events observed in the pion momentum region 211<P<229 MeV/c. At the measured central value of the branching ratio, the additional event had a signal-to-background ratio of 0.9.
Anisimovsky
V V
VV
Institute for Nuclear Research RAS, 60 October Revolution Prospect 7a, 117312 Moscow, Russia.
Artamonov
A V
AV
Bassalleck
B
B
Bhuyan
B
B
Blackmore
E W
EW
Bryman
D A
DA
Chen
S
S
Chiang
I-H
IH
Christidi
I-A
IA
Cooper
P S
PS
Diwan
M V
MV
Frank
J S
JS
Fujiwara
T
T
Hu
J
J
Ivashkin
A P
AP
Jaffe
D E
DE
Kabe
S
S
Kettell
S H
SH
Khabibullin
M M
MM
Khotjantsev
A N
AN
Kitching
P
P
Kobayashi
M
M
Komatsubara
T K
TK
Konaka
A
A
Kozhevnikov
A P
AP
Kudenko
Yu G
YG
Kushnirenko
A
A
Landsberg
L G
LG
Lewis
B
B
Li
K K
KK
Littenberg
L S
LS
Macdonald
J A
JA
Mildenberger
J
J
Mineev
O V
OV
Miyajima
M
M
Mizouchi
K
K
Mukhin
V A
VA
Muramatsu
N
N
Nakano
T
T
Nomachi
M
M
Nomura
T
T
Numao
T
T
Obraztsov
V F
VF
Omata
K
K
Patalakha
D I
DI
Petrenko
S V
SV
Poutissou
R
R
Ramberg
E J
EJ
Redlinger
G
G
Sato
T
T
Sekiguchi
T
T
Shinkawa
T
T
Strand
R C
RC
Sugimoto
S
S
Tamagawa
Y
Y
Tschirhart
R
R
Tsunemi
T
T
Vavilov
D V
DV
Viren
B
B
Yershov
N V
NV
Yoshimura
Y
Y
Yoshioka
T
T