Measurement of the CKM angle ${\phi }_1$ in $B^0\to \bar{D}{}^{(\ast )0}{h}^0$, $\bar{D}{}^0\to K_S^0{\pi }^{+}{\pi }^{-}$ decays with time-dependent binned Dalitz plot analysis

Abstract

We report a measurement of the CP violation parameter ${\phi }_1$ obtained in a time-dependent analysis of $B^0\to \bar{D}{}^{(\ast )0}{h}^0$ decays followed by $\bar{D}{}^0\to K_S^0{\pi }^{+}{\pi }^{-}$ decay. A model-independent measurement is performed using the binned Dalitz plot technique. The measured value is ${\phi }_1=11.7^{\circ }\pm 7.8^{\circ }(stat.)\pm 2.1^{\circ }(syst.)$. Treating $\sin 2{\phi }_1$ and $\cos 2{\phi }_1$ as independent parameters, we obtain $\sin 2{\phi }_1=0.43\pm 0.27(stat.)\pm 0.08(syst.)$ and $\cos 2{\phi }_1=1.06\pm 0.33(stat.{)}_{-0.15}^{+0.21}(syst.)$. The results are obtained with a full data sample of $772\times 10^{6}B\bar{B}$ pairs collected near the ${\rm Y}(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider.

Comments: Submitted to PRD