No Arabic abstract
Measurements of $C!P$ observables in $B^pm rightarrow D K^pm$ and $B^pm rightarrow D pi^pm$ decays are presented where the $D$ meson is reconstructed in the final states $K^pmpi^mp$, $pi^pm K^mp$, $K^+K^-$, $pi^+pi^-$, $K^pmpi^mp pi^+ pi^-$, $pi^pm K^mp pi^+ pi^-$ and $pi^+ pi^- pi^+ pi^-$. This analysis uses a sample of charged $B$ mesons from $pp$ collisions collected by the LHCb experiment in 2011 and 2012, corresponding to an integrated luminosity of 3.0 fb$^{-1}$. Various CP-violating effects are reported and together these measurements provide important input for the determination of the unitarity triangle angle $gamma$. The analysis of the four-pion $D$ decay mode is the first of its kind.
Measurements of $C!P$ observables in $B^pm rightarrow D^{(*)} K^pm$ and $B^pm rightarrow D^{(*)} pi^pm$ decays are presented, where $D^{(*)}$ indicates a neutral $D$ or $D^*$ meson that is an admixture of meson and anti-meson states. Decays of the $D^*$ meson to the $Dpi^0$ and $Dgamma$ final states are partially reconstructed without inclusion of the neutral pion or photon. Decays of the $D$ meson are reconstructed in the $K^pm pi^mp$, $K^+K^-$, and $pi^+pi^-$ final states. The analysis uses a sample of charged $B$ mesons produced in proton-proton collisions and collected with the LHCb experiment, corresponding to integrated luminosities of 2.0, 1.0, and 5.7 fb$^{-1}$ taken at centre-of-mass energies of 7, 8, and 13 TeV, respectively. The measurements of partially reconstructed $B^pm to D^* K^pm$ and $B^pm to D^* pi^pm$ with $D to K^mp pi^pm$ decays are the first of their kind, and a first observation of the $B^pm to (D pi^0)_{D^*} pi^pm$ decay is made with a significance of 6.1 standard deviations. All $C!P$ observables are measured with world-best precision, and in combination with other LHCb results will provide strong constraints on the CKM angle $gamma$.
Measurements of $CP$ observables in $B^{pm} rightarrow D K^{*pm}$ decays are presented, where $D$ denotes a superposition of $D^0$ and $overline{D^0}$ meson states. Decays of the $D$ meson to $K^{-}pi^{+}$, $K^{-}K^{+}$, $pi^{-}pi^{+}$, $K^{-}pi^{+}pi^{-}pi^{+}$ and $pi^{-}pi^{+}pi^{-}pi^{+}$ are used and the $K^{*pm}$ meson is reconstructed in the $K^{0}_{mathrm{S}}pi^{pm}$ final state. This analysis uses a data sample of $pp$ collisions collected with the LHCb experiment, corresponding to integrated luminosities of 1 $mathrm{fb}^{-1}$, 2 $mathrm{fb}^{-1}$ and 1.8 $mathrm{fb}^{-1}$ at centre-of-mass energies $sqrt{s} = $ 7 TeV, 8 TeV and 13 TeV, respectively. The sensitivity of the results to the CKM angle $gamma$ is discussed.
Measurements of $CP$ observables in $B^pm rightarrow D^{(*)} K^pm$ and $B^pm rightarrow D^{(*)} pi^pm$ decays are presented, where $D^{(*)}$ indicates a neutral $D$ or $D^*$ meson that is an admixture of $D^{(*)0}$ and $bar{D}^{(*)0}$ states. Decays of the $D^*$ meson to the $Dpi^0$ and $Dgamma$ final states are partially reconstructed without inclusion of the neutral pion or photon, resulting in distinctive shapes in the $B$ candidate invariant mass distribution. Decays of the $D$ meson are fully reconstructed in the $K^pm pi^mp$, $K^+ K^-$ and $pi^+ pi^-$ final states. The analysis uses a sample of charged $B$ mesons produced in $pp$ collisions collected by the LHCb experiment, corresponding to an integrated luminosity of 2.0, 1.0 and 2.0 fb$^{-1}$ taken at centre-of-mass energies of $sqrt{s}$ = 7, 8 and 13 TeV, respectively. The study of $B^{pm} to D^{*} K^{pm}$ and $B^{pm} to D^{*} pi^{pm}$ decays using a partial reconstruction method is the first of its kind, while the measurement of $B^{pm} to D K^{pm}$ and $B^{pm} to D pi^{pm}$ decays is an update of previous LHCb measurements. The $B^{pm} to D K^{pm}$ results are the most precise to date.
A search for $CP$ violation in $D^{pm}rightarrow eta^{prime} pi^{pm}$ and $D^{pm}_{s}rightarrow eta^{prime} pi^{pm}$ decays is performed using proton-proton collision data, corresponding to an integrated luminosity of $3$ fb$^{-1}$, recorded by the LHCb experiment at centre-of-mass energies of $7$ and $8$ TeV. The measured $CP$-violating charge asymmetries are $A_{CP}(D^{pm} rightarrow eta^{prime} pi^{pm})=(-0.61pm 0.72 pm 0.53 pm 0.12)%$ and $A_{CP}(D^{pm}_{s}rightarrow eta^{prime} pi^{pm})=(-0.82pm 0.36 pm 0.22 pm 0.27)%$, where the first uncertainties are statistical, the second systematic, and the third are the uncertainties on the $A_{CP}(D^{pm} rightarrow K^0_S pi^{pm})$ and $A_{CP}(D^{pm}_{s}rightarrow phi pi^{pm})$ measurements used for calibration. The results represent the most precise measurements of these asymmetries to date.