Observation and branching fraction measurement of the decay ${\Xi }_b^{-}\to {\Lambda }_b^0{\pi }^{-}$

Abstract

The decay ${\Xi }_b^{-}\to {\Lambda }_b^0{\pi }^{-}$ is observed using a proton-proton collision data sample collected at center-of-mass energy $\sqrt{s}=13$ TeV with the LHCb detector, corresponding to an integrated luminosity of 5.5 fb${}^{-1}$. This process is mediated by the $s\to u\bar{u}d$ quark-level transition, where the $b$ quark in the ${\Xi }_b^{-}$ baryon is a spectator in the decay. Averaging the results obtained using the two ${\Lambda }_b^0$ decay modes, ${\Lambda }_b^0\to {\Lambda }_c^{+}{\pi }^{-}$ and ${\Lambda }_b^0\to {\Lambda }_c^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}$, the relative production ratio is measured to be $(f_{{\Xi }_b^{-}}/f_{{\Lambda }_b^0})\mathcal{B}({\Xi }_b^{-}\to {\Lambda }_b^0{\pi }^{-})=(7.3\pm 0.8\pm 0.6)\times 10^{-4}$. Here the uncertainties are statistical and systematic, respectively, and $f_{{\Xi }_b^{-}}(f_{{\Lambda }_b^0})$ is the fragmentation fraction for a $b$ quark into a ${\Xi }_b^{-}$ (${\Lambda }_b^0$) baryon. Using an independent measurement of $f_{{\Xi }_b^{-}}/f_{{\Lambda }_b^0}$, the branching fraction $\mathcal{B}({\Xi }_b^{-}\to {\Lambda }_b^0{\pi }^{-})=(0.89\pm 0.10\pm 0.07\pm 0.29)\%$ is obtained, where the last uncertainty is due to the assumed SU(3) flavor symmetry in the determination of $f_{{\Xi }_b^{-}}/f_{{\Lambda }_b^0}$.

arXiv comment14 pages, 4 figures. All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-015.html (LHCb public pages)

References in corpus (31)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Brief Introduction to PYTHIA 8.1
• LHCb Detector Performance
• Non-Standard Heavy Mesons and Baryons, an Experimental Review
• sPlot: a statistical tool to unfold data distributions
• The LHCb Trigger and its Performance in 2011
• Exotica
• Performance of the LHCb RICH detector at the LHC
• Performance of the LHCb Vertex Locator
• Efficient, reliable and fast high-level triggering using a bonsai boosted decision tree
• Performance of the LHCb muon system
• Measurement of the track reconstruction efficiency at LHCb
• 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
• Design and performance of the LHCb trigger and full real-time reconstruction in Run 2 of the LHC
• LHCb Topological Trigger Reoptimization
• ReDecay: A novel approach to speed up the simulation at LHCb
• Precision measurement of the mass and lifetime of the ${\Xi }_b^0$ baryon
• Observation of a new ${\Xi }_b^0$ state
• Measurement of the mass and production rate of ${\Xi }_b^{-}$ baryons
• Evidence for the strangeness-changing weak decay ${\Xi }_b^{-}\to {\Lambda }_b^0{\pi }^{-}$
• Light-Quark Decays in Heavy Hadrons
• Study of heavy quark conserving weak decays in the quark model
• Weak decays Xi_Q -> Lambda_Q pi
• Heavy-Flavor-Conserving Hadronic Weak Decays of Heavy Baryons
• Heavy-Flavor-Conserving Hadronic Weak Decays of Charmed and Bottom Baryons: an Update
• Heavy-Flavor-Conserving Hadronic Weak Decays of Charmed and Bottom Baryons
• Comments on Diquarks, Strong Binding and a Large Hidden QCD Scale
• The decays ${\Xi }_b\to {\Lambda }_b\pi$ and diquark correlations in hyperons
• S-wave nonleptonic hyperon decays and ${\Xi }_b^{-}\to {\pi }^{-}{\Lambda }_b$

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