The e+e– → π+π–π0χbJ (J = 0,1,2) processes are studied using a 118 fb–1 data sample acquired with the Belle detector at a center-of-mass energy of 10.867 GeV. Unambiguous π+π–π0χbJ (J = 1,2), ωχb1 ...signals are observed, and indication for ωχb2 is seen, both for the first time, and the corresponding cross section measurements are presented. No significant π+π–π0χb0 or ωχb0 signals are observed, and 90% confidence level upper limits on the cross sections for these two processes are obtained. In the π+π–π0 invariant mass spectrum, significant non-ω signals are also observed. In conclusion, we search for the X(3872)-like state (named Xb) decaying into ωΥ(1S); no significant signal is observed with a mass between 10.55 and 10.65 GeV/c2.
A
bstract
We present a measurement of the time-dependent
CP
violation parameters in
B
0
→
η
′
K
0
decays. The measurement is based on the full data sample containing 772 × 10
6
B
B
¯
pairs collected ...at the Υ(4
S
) resonance using the Belle detector at the KEKB asymmetric-energy
e
+
e
−
collider. The measured values of the mixing-induced and direct
CP
violation parameters are:
sin
2
ϕ
1
eff
=
+
0.68
±
0.07
±
0.03
,
A
η
′
K
0
=
+
0.03
±
0.05
±
0.04
,
where the first uncertainty is statistical and the second is systematic. The values obtained are the most accurate to date. Furthermore, these results are consistent with our previous measurements and with the world-average value of sin 2
ϕ
1
measured in
B
0
→
J/ψK
0
decays.
In this work, we observe D0- D ¯ 0 mixing in the decay D0 → K+π- using a data sample of integrated luminosity 976 fb-1 collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. ...We measure the mixing parameters x'2= ( 0.09±0.22 ) ×10-3 and y'= ( 4.6±3.4 ) ×10-3 and the ratio of doubly Cabibbo-suppressed to Cabibbo-favored decay rates RD= ( 3.53±0.13 ) ×10-3 , where the uncertainties are statistical and systematic combined. Our measurement excludes the no-mixing hypothesis at the 5.1 standard deviation level.
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