Observation of the suppressed ${\Lambda }_b^0\to Dp{K}^{-}$ decay with $D\to K^{+}{\pi }^{-}$ and measurement of its $CP$ asymmetry

Abstract

A study of ${\Lambda }_b^0$ baryon decays to the $Dp{K}^{-}$ final state is presented based on a proton-proton collision data sample corresponding to an integrated luminosity of 9 fb${}^{-1}$ collected with the LHCb detector. Two ${\Lambda }_b^0$ decays are considered, ${\Lambda }_b^0\to Dp{K}^{-}$ with $D\to K^{-}{\pi }^{+}$ and $D\to K^{+}{\pi }^{-}$, where $D$ represents a superposition of $D^0$ and ${\overline{D}}^0$ states. The latter process is expected to be suppressed relative to the former, and is observed for the first time. The ratio of branching fractions of the two decays is measured, and the $CP$ asymmetry of the suppressed mode, which is sensitive to the CKM angle $\gamma$, is also reported.

arXiv commentAll figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2021-027.html (LHCb public pages). v2 matches published version

References in corpus (23)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Brief Introduction to PYTHIA 8.1
• LHCb Detector Performance
• sPlot: a statistical tool to unfold data distributions
• The LHCb Trigger and its Performance in 2011
• Performance of the LHCb RICH detector at the LHC
• Enhanced CP Violation with $B\to K{D}^0({\overline{D}}^0)$ Modes and Extraction of the CKM Angle gamma
• Decay Chain Fitting with a Kalman Filter
• Performance of the LHCb Vertex Locator
• Performance of the LHCb Outer Tracker
• The RooFit toolkit for data modeling
• Improved Methods for Observing CP Violation in B+/- --> K+/- D0 and Measuring the CKM Phase gamma
• Selection and processing of calibration samples to measure the particle identification performance of the LHCb experiment in Run 2
• Improved performance of the LHCb Outer Tracker in LHC Run 2
• Study of the $D^{0}p$ amplitude in ${\Lambda }_b^0\to D^{0}p{\pi }^{-}$ decays
• Studies of beauty baryon decays to $D^{0}p{h}^{-}$ and ${\Lambda }_c^{+}{h}^{-}$ final states
• Kernel density estimation of a multidimensional efficiency profile
• B Production Asymmetries in Perturbative QCD
• Observation of a ${\Lambda }_b^0-{\overline{\Lambda }}_b^0$ production asymmetry in proton-proton collisions at $\sqrt{s}=7\text{ and }8\text{TeV}$
• Possibility of extracting the weak phase $\gamma$ from ${\Lambda }_b\to \Lambda D^0$ decays
• Lambda_c^+/Lambda_c^- and Lambda_b^0/\bar{Lambda}_b^0 production asymmetry at the LHC from heavy quark recombination
• ${\Lambda }_b\to \Lambda +D({\bar{D}}^0)$ decays and CP-violation

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