اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدObservation of $B^{+} rightarrow pbar{Lambda} K^+ K^-$ and $B^{+} rightarrow bar{p}Lambda K^+ K^+$
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We report the study of OK and SK using a $772 times 10^6$ $Bbar{B}$ pair data sample recorded on the $Upsilon({rm 4S})$ resonance with the Belle detector at KEKB. The following branching fractions are measured: $mathcal{B}$(OKPHSP) $=$ $(4.22^{+0.45}_{-0.44}pm 0.51)times10^{-6}$, $mathcal{B}$(SKPHSP) $=$ $(3.81^{+0.39}_{-0.37} pm 0.45)times 10^{-6}$, $mathcal{B}$(ETACD+c.c.) $=$ $(2.91^{+0.37}_{-0.35}pm 0.36)times 10^{-3}$ and $mathcal{B}$(PLPHI) $=$ $(8.18 pm 2.15 pm 0.79)times10^{-7}$, where c.c. denotes the corresponding charge-conjugation process. The intermediate resonance decays are excluded in the four-body decay measurements. We also found evidences for $mathcal{B}$(ETACS+c.c.) $=$ $(3.59 pm 1.52 pm 0.47) times 10^{-3}$ and $mathcal{B}$(LLKO) $=$ $(2.30 pm 0.65 pm 0.25) times 10^{-6}$. No significant signals are found for JPSIS+c.c. and LLKS ; we set the 90% confidence level upper limits on their decay branching fractions as $< 1.85times10^{-3}$ and $< 2.14times10^{-6}$, respectively.
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