Measurement of $CP$ violation and constraints on the CKM angle $γ$ in $B^{\pm}\rightarrow D K^{\pm}$ with $D \rightarrow K_S^0 π^+ π^-$ decays

Journal article

A model-dependent amplitude analysis of $B^{\pm} \rightarrow D K^{\pm}$ with $D \rightarrow K_S^0 \pi^+ \pi^-$ decays is performed using proton-proton collision data, corresponding to an integrated luminosity of $1$ fb$^{-1}$, recorded by LHCb at a centre-of-mass energy of $7$ TeV in $2011$. Values of the $CP$ violation observables $x_{\pm}$ and $y_{\pm}$, which are sensitive to the CKM angle $\gamma$, are measured to be \begin{align*} x_- and= +0.027 \pm 0.044 ^{+0.010}_{-0.008} \pm 0.001, \\ y_- and= +0.013 \pm 0.048 ^{+0.009}_{-0.007} \pm 0.003, \\ x_+ and= -0.084 \pm 0.045 \pm 0.009 \pm 0.005, \\ y_+ and= -0.032 \pm 0.048 ^{+0.010}_{-0.009} \pm 0.008, \end{align*} where the first uncertainty is statistical, the second systematic and the third arises from the uncertainty of the $D \rightarrow K_S^0 \pi^+ \pi^-$ amplitude model. The value of $\gamma$ is determined to be $(84^{+49}_{-42})^\circ$, including all sources of uncertainty. Neutral $D$ meson mixing is found to have negligible effect.

Authors: collaboration, L; Aaij, R; Adeva, B; Adinolfi, M; Affolder, A

• Publication status: Published
• Publisher: Elsevier
• Journal: Nuclear Physics
• Volume: 888
• Issue: 1
• Pages: 9-193
• Publication date: 2014-07-23
• DOI: 10.1016/j.nuclphysb.2014.09.015
• ISSN: 0550-3213
• Language: English
• Keywords: hep-ex