# The 2009 Europhysics Conference on High Energy Physics

Jul 16 – 22, 2009
Kraków, Poland
Europe/Warsaw timezone

## b -> s hadronic decays at Belle

Jul 18, 2009, 9:00 AM
15m
Large Lecture - Hall A (Kraków, Poland)

### Large Lecture - Hall A

#### Kraków, Poland

The Auditorium Maximum of the Jagiellonian University 33 Krupnicza Street 31-123 Kraków
Flavour Physics

### Speaker

Sunghyon KYEONG (Yonsei University)

### Description

Study of $B^+ \to \rho^+ \omega$ decay at Belle We report the results of a search for the charmless decay $B^+ \to \rho^+ \omega$. The analysis is based on a large data sample recorded at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. Study of inclusive $B \to X_s \eta$ at Belle We report results on a search for inclusive high momentum $\eta$ decays of the $B$ meson using a large data sample accumulated at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric $e^+ e^-$ collider. Measurements of $B \to \phi \phi K$ Decays We report improved measurements of the charmless decay $B \to \phi \phi K$ using a 605 fb$^{-1}$ data sample collected on the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric energy $e^+ e^-$ collider. The results of the related charmonium decays such as $B \to J/\psi K$ and $J/\psi \to \phi \phi$ are also shown. Measurements of Charmless Hadronic $b\to s$ Penguin Decays in the $\pi^+\pi^- K^+\pi^-$ Final State and Observation of $B^0\to \rho^0 K^+\pi^-$ We report measurements of charmless hadronic $B^0$ decays into the $\pi^ \pi^- K^+\pi^-$ final state. The analysis uses a sample of $657\times10^6$ $B\bar{B}$ pairs collected with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider at the $Y(4S)$ resonance. The decay $B^0\to\rho^0 K^+\pi^-$ is observed for the first time; the significance is $5.0\sigma$ and the corresponding partial branching fraction for $M_{K\pi} \in (0.75,1.20)~{\rm GeV}/c^2$ is $[2.8 \pm 0.5(stat) \pm 0.5(syst)]\times 10^{-6}$. We also obtain the first evidence for $B^0 \to f_0 K^+\pi^-$ with $3.5\sigma$ significance and for $B^0 \to\pi^+\pi^-K^{*0}$ with $4.5\sigma$ significance. For the two-body decays $B^0\to\rho^0 K^{*0}$ and $B^0\to f_0 K^{*0}$, the significances are $2.7\sigma$ and $2.5\sigma$, respectively, and the upper limits on the branching fractions are $3.4 \times 10 ^{-6}$ and $2.2 \times 10^{-1}$ at 90\% confidence level.

### Primary author

Sunghyon KYEONG (Yonsei University)

 Slides