Search for $CP$ violation in $D_{(s)}^{+}\to h^{+}{\pi }^0$ and $D_{(s)}^{+}\to h^{+}\eta$ decays

Abstract

Searches for $CP$ violation in the two-body decays $D_{(s)}^{+}\to h^{+}{\pi }^0$ and $D_{(s)}^{+}\to h^{+}\eta$ (where $h^{+}$ denotes a ${\pi }^{+}$ or $K^{+}$ meson) are performed using $pp$ collision data collected by the LHCb experiment corresponding to either 9 fb${}^{-1}$ or 6 fb${}^{-1}$ of integrated luminosity. The ${\pi }^0$ and $\eta$ mesons are reconstructed using the $e^{+}{e}^{-}\gamma$ final state, which can proceed as three-body decays ${\pi }^0\to e^{+}{e}^{-}\gamma$ and $\eta \to e^{+}{e}^{-}\gamma$, or via the two-body decays ${\pi }^0\to \gamma \gamma$ and $\eta \to \gamma \gamma$ followed by a photon conversion. The measurements are made relative to the control modes $D_{(s)}^{+}\to K_S^0{h}^{+}$ to cancel the production and detection asymmetries. The $CP$ asymmetries are measured to be \begin{align} \mathcal{A}_{CP}(D^{+}\rightarrow π^{+}π^{0}) &= (-1.3 \pm 0.9 \pm 0.6 )\%, \end{align} \begin{align} \mathcal{A}_{CP}(D^{+}\rightarrow K^{+}π^{0}) &= (-3.2 \pm 4.7 \pm 2.1 )\%, \end{align} \begin{align} \mathcal{A}_{CP}(D^{+}\rightarrow π^{+}η) &= (-0.2 \pm 0.8 \pm 0.4 )\%, \end{align} \begin{align} \mathcal{A}_{CP}(D^{+}\rightarrow K^{+}η) &= (-6 \pm 10 \pm 4 )\%, \end{align} \begin{align} \mathcal{A}_{CP}(D_{s}^{+}\rightarrow K^{+}π^{0}) &= (-0.8 \pm 3.9 \pm 1.2 )\%, \end{align} \begin{align} \mathcal{A}_{CP}(D_{s}^{+}\rightarrow π^{+}η) &= (0.8 \pm 0.7 \pm 0.5 )\%, \end{align} \begin{align} \mathcal{A}_{CP}(D_{s}^{+}\rightarrow K^{+}η) &= (0.9 \pm 3.7 \pm 1.1 )\%, \end{align} where the first uncertainties are statistical and the second systematic. These results are consistent with no $CP$ violation and mostly constitute the most precise measurements of ${\mathcal{A}}_{CP}$ in these decay modes to date.

arXiv commentAll figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2021-001.html (LHCb public pages)

References in corpus (21)

• A Brief Introduction to PYTHIA 8.1
• LHCb Detector Performance
• sPlot: a statistical tool to unfold data distributions
• Observation of $CP$ violation in charm decays
• Selection and processing of calibration samples to measure the particle identification performance of the LHCb experiment in Run 2
• Branching ratios and direct CP asymmetries in $D\to PP$ decays
• Direct CP violation in two-body hadronic charmed meson decays
• CP Violation and Flavor SU(3) Breaking in D-meson Decays
• CP asymmetries in singly-Cabibbo-suppressed $D$ decays to two pseudoscalar mesons
• Measurement of $CP$ asymmetry in $D^0\to K^{-}{K}^{+}$ and $D^0\to {\pi }^{-}{\pi }^{+}$ decays
• ReDecay: A novel approach to speed up the simulation at LHCb
• Testing for new physics in singly Cabibbo suppressed D decays
• On $SU(3{)}_F$ Breaking through Final State Interactions and CP Asymmetries in $D\to PP$ Decays
• Measurements of D Meson Decays to Two Pseudoscalar Mesons
• CP violating asymmetries in charged D meson decays
• Exploiting CP-asymmetries in rare charm decays
• Flavor Symmetry, K^0-\bar{K}^0 Mixing and New Physics Effects on CP Violation in D^{\pm} and D^{\pm}_s Decays
• Mapping the material in the LHCb vertex locator using secondary hadronic interactions
• Calibration and performance of the LHCb calorimeters in Run 1 and 2 at the LHC
• Search for $CP$ violation in the $D^{+}\to {\pi }^{+}{\pi }^0$ decay at Belle
• Search for $CP$ violation in $D_s^{+}\to K_S^0{\pi }^{+}$, $D^{+}\to K_S^0{K}^{+}$ and $D^{+}\to \varphi {\pi }^{+}$ decays

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• Measurement of the CP asymmetry in $D^{+}\to {\pi }^{+}{\pi }^0$ decays at Belle II
• A Review of $CP$ Violation Measurements in Charm at LHCb
• Search for $D^{+}\to K^{-}{K}_s^0{\pi }^{+}{\pi }^{+}{\pi }^0$ at Belle