Measurement of $D^0-{\overline{D}}^0$ mixing and search for $CP$ violation with $D^0\to K^{+}{\pi }^{-}$ decays

Abstract

A measurement of the time-dependent ratio of the $D^0\to K^{+}{\pi }^{-}$ to ${\overline{D}}^0\to K^{+}{\pi }^{-}$ decay rates is reported. The analysis uses a sample of proton-proton collisions corresponding to an integrated luminosity of 6 fb${}^{-1}$ recorded by the LHCb experiment from 2015 through 2018 at a center-of-mass energy of 13 TeV. The $D^0$ meson is required to originate from a $D^{\ast +}\to D^0{\pi }^{+}$ decay, such that its flavor at production is inferred from the charge of the accompanying pion. The measurement is performed simultaneously for the $K^{+}{\pi }^{-}$ and $K^{-}{\pi }^{+}$ final states, allowing both mixing and $CP$-violation parameters to be determined. The value of the ratio of the decay rates at production is determined to be $R_{K\pi }=(343.1\pm 2.0)\times 10^{-5}$. The mixing parameters are measured to be $c_{K\pi }=(51.4\pm 3.5)\times 10^{-4}$ and $c_{K\pi }^{\prime }=(13\pm 4)\times 10^{-6}$, where $\sqrt{R_{K\pi }}{c}_{K\pi }$ is the linear coefficient of the expansion of the ratio as a function of decay time in units of the $D^0$ lifetime, and $c_{K\pi }^{\prime }$ is the quadratic coefficient, both averaged between the $K^{+}{\pi }^{-}$ and $K^{-}{\pi }^{+}$ final states. The precision is improved relative to the previous best measurement by approximately 60%. No evidence for $CP$ violation is found.

arXiv commentAll figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://lbfence.cern.ch/alcm/public/analysis/full-details/1800

References in corpus (52)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Brief Introduction to PYTHIA 8.1
• LHCb Detector Performance
• The LHCb Trigger and its Performance in 2011
• Decay Chain Fitting with a Kalman Filter
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2021
• Efficient, reliable and fast high-level triggering using a bonsai boosted decision tree
• Observation of $CP$ violation in charm decays
• New Physics and CP Violation in Singly Cabibbo Suppressed D Decays
• Evidence for D0-anti-D0 Mixing
• Nonleptonic weak decays of charmed mesons
• Tesla : an application for real-time data analysis in High Energy Physics
• The Standard Model confronts CP violation in $D^0\to {\pi }^{+}{\pi }^{-}$ and $D^0\to K^{+}{K}^{-}$
• Reweighting with Boosted Decision Trees
• Testing New Indirect CP Violation
• The Emergence of the $\Delta U=0$ Rule in Charm Physics
• Direct CP asymmetry in $D\to {\pi }^{-}{\pi }^{+}$ and $D\to K^{-}{K}^{+}$ in QCD-based approach
• On Indirect CP Violation and Implications for D0-\overline{D0} and Bs -\overline{Bs} mixing
• Measurement of D0-D0bar mixing parameters and search for CP violation using D0->K+pi- decays
• Measurement of the mass difference between neutral charm-meson eigenstates
• On $SU(3{)}_F$ Breaking through Final State Interactions and CP Asymmetries in $D\to PP$ Decays
• $\Delta A_{CP}$ within the Standard Model and beyond
• SU(3) Breaking Effects in Charmed Meson Decays
• Observation of the mass difference between neutral charm-meson eigenstates
• Simultaneous determination of CKM angle $\gamma$ and charm mixing parameters
• Search for CP Violation in Neutral D Meson Cabibbo-suppressed Three-body Decays
• Strong phases and D0-anti-D0 mixing parameters
• Mixing and $CP$ violation in the charm system
• Updated Measurement of the Strong Phase in D0 --> K+pi- Decay Using Quantum Correlations in e+e- --> D0 D0bar at CLEO
• Experimental Implications of Large CP Violation and Final State Interactions in the Search for $D^0\overline{D^0}$ Mixing
• Dispersive and Absorptive CP Violation in $D^0-\overline{D^0}$ Mixing
• Measurement of the time-integrated $CP$ asymmetry in $D^0\to K^{-}{K}^{+}$ decays
• Theoretical and experimental status of rare charm decays
• Measurement of the CKM angle $\gamma$ in $B^{\pm }\to D{K}^{\pm }$ and $B^{\pm }\to D{\pi }^{\pm }$ decays with $D\to K_{\mathrm{S}}^0{h}^{+}{h}^{-}$
• Updated determination of $D^0$-$\overline{D}{}^0$ mixing and CP violation parameters with $D^0\to K^{+}{\pi }^{-}$ decays
• Direct CP violation in beauty and charm hadron decays
• New Physics Effects in Doubly Cabibbo Suppressed D Decays
• Final-state interactions in the CP asymmetries of charm-meson two-body decays
• Observation of $D^0-{\bar{D}}^0$ Mixing in $e^{+}{e}^{-}$ Collisions
• Search for time-dependent $CP$ violation in $D^0\to K^{+}{K}^{-}$ and $D^0\to {\pi }^{+}{\pi }^{-}$ decays
• Measurement of $CP$ observables in $B^{\pm }\to D^{(\ast )}{K}^{\pm }$ and $B^{\pm }\to D^{(\ast )}{\pi }^{\pm }$ decays using two-body $D$ final states
• Measurement of the charm-mixing parameter $y_{CP}$
• Updated measurement of decay-time-dependent CP asymmetries in $D^0\to K^{+}{K}^{-}$ and $D^0\to {\pi }^{+}{\pi }^{-}$ decays
• Strong phases, asymmetries, and SU(3) symmetry breaking in D --> K pi decays
• Improved measurement of the strong-phase difference ${\delta }_D^{K\pi }$ in quantum-correlated $D\bar{D}$ decays
• Measurement of the charm mixing parameter $y_{CP}-y_{CP}^{K\pi }$ using two-body $D^0$ meson decays
• Measurement of the CKM angle $\gamma$ with $B^{\pm }\to D[K^{\mp }{\pi }^{\pm }{\pi }^{\pm }{\pi }^{\mp }]h^{\pm }$ decays using a binned phase-space approach
• Search for time-dependent $CP$ violation in $D^0\to {\pi }^{+}{\pi }^{-}{\pi }^0$ decays
• Model-independent measurement of charm mixing parameters in $\bar{B}\to D^0(\to K_S^0{\pi }^{+}{\pi }^{-}){\mu }^{-}{\bar{\nu }}_{\mu }X$ decays
• Search for $CP$ violation in the phase space of $D^0\to {\pi }^{-}{\pi }^{+}{\pi }^0$ decays with the energy test
• Recent advances in charm mixing and $CP$ violation at LHCb

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