Measurement of Time-Dependent $CP$-Violating Asymmetries in ${B}^{0}\ensuremath{\rightarrow}{K}^{*0}\ensuremath{\gamma}\left({K}^{*0}\ensuremath{\rightarrow}{K}_{S}^{0}{\ensuremath{\pi}}^{0}\right)$ Decays

Measurement of Time-Dependent $C P$ -Violating Asymmetries in $B^{0} \to K^{* 0} γ (K^{* 0} \to K_{S}^{0} π^{0})$ Decays

B. Aubert et al. (The BABAR Collaboration)

Phys. Rev. Lett. 93, 201801 – Published 8 November 2004

Abstract

We present a measurement of the time-dependent $C P$ -violating asymmetries in $B^{0} \to K^{* 0} γ (K^{* 0} \to K_{S}^{0} π^{0})$ decays based on $124 \times 10^{6}$ $Υ (4 S) \to B \bar{B}$ decays collected with the BABAR detector at the PEP-II asymmetric-energy $B$ Factory at the Stanford Linear Accelerator Center. In a sample containing $105 \pm 14$ signal decays, we measure $S_{K^{*} γ} = 0.25 \pm 0.63 \pm 0.14$ and $C_{K^{*} γ} = - 0.57 \pm 0.32 \pm 0.09$ , where the first error is statistical and the second, systematic.