The 2009 Europhysics Conference on High Energy Physics

Inclusive radiative B meson decays at Belle

17 Jul 2009, 09:00

15m

Large (Kraków, Poland)

Flavour Physics II. Flavour Physics

Speaker

Bostjan Golob (University of Ljubljana, Jozef Stefan Inst.)

Description

Improved measurement of inclusive radiative $B$-meson decays We report a fully inclusive measurement of the flavor changing neutral current decay $B\to X_s\gamma$ in the energy range $1.7\mathrm{G}\mathrm{e}\mathrm{V}\le E_{\gamma }^{\mathrm{c}.\mathrm{m}.\mathrm{s}.}\le 2.8\mathrm{G}\mathrm{e}\mathrm{V}$, covering 97\% of the total spectrum, where c.m.s. is the center of mass system. Using 605 fb${}^{-1}$ of data we obtain measurements of the partial branching fraction and first and second moments of the photon energy spectrum for lower energy thresholds including and above $1.7\mathrm{G}\mathrm{e}\mathrm{V}$. Improved Measurement of the Electroweak Penguin Process $B\to X_s{\ell }^{+}{\ell }^{-}$ We present a measurement of the branching fraction for the electroweak penguin process $B\to X_s{\ell }^{+}{\ell }^{-}$, where $\ell$ is an electron or a muon and $X_s$ is a hadronic system containing an $s$-quark. The $X_s$ hadronic system is reconstructed with one $K^{\pm }$ or $K_s^0$ and up to four pions, where at most one pion can be neutral. The measurement is based on a data sample four times larger than used in the previous analysis, accumulated at the $\mathrm{{\rm Y}}(4S)$ resonance with the Belle detector at the KEKB $e^{+}{e}^{-}$ asymmetric-energy collider.

Presentation materials

Slides

Bradiative_eps09_pdf.pdf

Bradiative_eps09_ppt.ppt