Precision measurement of the ${\Lambda }_c^{+}$, ${\Xi }_c^{+}$ and ${\Xi }_c^0$ baryon lifetimes

Abstract

We report measurements of the lifetimes of the ${\Lambda }_c^{+}$, ${\Xi }_c^{+}$ and ${\Xi }_c^0$ charm baryons using proton-proton collision data at center-of-mass energies of 7 and 8\tev, corresponding to an integrated luminosity of 3.0 fb${}^{-1}$, collected by the LHCb experiment. The charm baryons are reconstructed through the decays ${\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+}$, ${\Xi }_c^{+}\to p{K}^{-}{\pi }^{+}$ and ${\Xi }_c^0\to p{K}^{-}{K}^{-}{\pi }^{+}$, and originate from semimuonic decays of beauty baryons. The lifetimes are measured relative to that of the $D^{+}$ meson, and are determined to be \begin{align*} τ_{Λ_c^+} &= 203.5\pm1.0\pm1.3\pm1.4~{\rm fs}, \newline τ_{Ξ_c^+} &= 456.8\pm3.5\pm2.9\pm3.1~{\rm fs}, \newline τ_{Ξ_c^0} &= 154.5\pm1.7\pm1.6\pm1.0~{\rm fs}, \end{align*} where the uncertainties are statistical, systematic, and due to the uncertainty in the $D^{+}$ lifetime. The measurements are approximately 3--4 times more precise than the current world average values. The ${\Lambda }_c^{+}$ and ${\Xi }_c^{+}$ lifetimes are in agreement with previous measurements; however, the ${\Xi }_c^0$ baryon lifetime is approximately 3.3 standard deviations larger than the world average value.

arXiv comment9 pages, 2 figures. All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2019-008.html

References in corpus (26)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Brief Introduction to PYTHIA 8.1
• LHCb Detector Performance
• PHOTOS Monte Carlo: a precision tool for QED corrections in Z and W decays
• 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
• Nonperturbative Corrections to Inclusive Beauty and Charm Decays: QCD versus Phenomenological Models
• Performance of the LHCb Vertex Locator
• Efficient, reliable and fast high-level triggering using a bonsai boosted decision tree
• The Rule of Discarding $1/N_c$ in Inclusive Weak Decays
• Strong Decays of Charmed Baryons in Heavy Hadron Chiral Perturbation Theory: An Update
• The Rule of Discarding $1/N_c$ in Inclusive Weak Decays. II
• Performance of the Muon Identification at LHCb
• Dimension-six matrix elements for meson mixing and lifetimes from sum rules
• D-meson lifetimes within the heavy quark expansion
• Measurements of the $B^{+}$, $B^0$, $B_s^0$ meson and ${\Lambda }_b^0$ baryon lifetimes
• B Decays and the Heavy-Quark Expansion
• Precision measurements of the Lambda_c+ and D0 lifetimes
• The QCD Perspective on Lifetimes of Heavy-Flavour Hadrons
• A New Measurement of the Cascade(c)+ Lifetime
• A High Statistics Measurement of the Lambdac+ Lifetime
• Measurement of the ${\Lambda }_c^{+}$ Lifetime
• Lifetimes of Charmed Hadrons Revisited. Facts and fancy
• A new measurement of the ${\Xi }_c^0$ lifetime

Cited by in corpus (21)

• Charmed Baryon Physics Circa 2021
• Two-body hadronic weak decays of antitriplet charmed baryons
• First Lattice QCD determination of semileptonic decays of charmed-strange baryons ${\Xi }_c$
• Revisiting semileptonic decays of ${\Lambda }_{b(c)}$ supported by baryon spectroscopy
• Charmed Baryon Weak Decays with Vector Mesons
• Charmed baryon decays in $SU(3{)}_F$ symmetry
• Direct CP violation in beauty and charm hadron decays
• First branching fraction measurement of the suppressed decay ${\Xi }_c^0\to {\pi }^{-}{\Lambda }_c^{+}$
• Semileptonic weak decays of anti-triplet charmed baryons in the light-front formalism
• Semileptonic decays of ${\Lambda }_c^{+}$ in dynamical approaches
• Study on the ${\Omega }_c^0$ States Decaying to ${\Xi }_c^{+}{K}^{-}$ in $pp$ collisions at $\sqrt{s}=7$, 13 TeV
• Precise measurement of the $D^0$ and $D^{+}$ lifetimes at Belle II
• Measurement of Branching Fractions of Singly Cabibbo-suppressed Decays ${\Lambda }_c^{+}\to {\Sigma }^0{K}^{+}$ and ${\Sigma }^{+}{K}_S^0$
• Update on splitting of lifetimes of $c$ and $b$ hyperons within the heavy quark expansion and decays ${\Xi }_Q\to {\Lambda }_Q\pi$
• Measurement of the ${\Lambda }_c^{+}$ lifetime
• ${\Xi }_c\to \Xi$ form factors from lattice QCD with domain-wall quarks: A new piece in the puzzle of ${\Xi }_c^0$ decay rates
• Charm Physics at the Super $\tau$-Charm Factory
• Study of the nonleptonic decay ${\Xi }_c^0\to {\Lambda }_c^{+}{\pi }^{-}$ in the covariant confined quark model
• Precision measurement of the ${\Xi }_b^{-}$ baryon lifetime
• Measurement of the lifetimes of promptly produced ${\Omega }_c^0$ and ${\Xi }_c^0$ baryons
• The strangest lifetime: A bizarre story of $\tau ({\Omega }_c^0)$