Measurement of the Ωc0 baryon lifetime with LHCb

Ward, Jake Alexander (2021) Measurement of the Ωc0 baryon lifetime with LHCb. MSc(R) thesis, University of Glasgow.

Abstract

The results of the measurement of the Ωc0 charmed baryon lifetime via the Ωb → Ωc0π decay mode are presented in this thesis. The result makes use of the proton-proton collision data collected by the LHCb detector at CERN in the years 2011-2012 and 2015-2016 using the full 8.7 fb⁻¹ total integrated luminosity data.
The lifetime of the Ωc0 baryon was measured to be
τΩc0 = 238 ± 33 (stat) ± 21 (syst) ± 1 (τD⁰) fs,
where the first uncertainty is statistical, the second systematic, and the third due to the use of the world-average D⁰ lifetime. The lifetime is measured as a ratio of Ωb → Ωc0π to B → D⁰π decays in order to cancel out the decay time dependent reconstruction and selection efficiencies, using 284 Ωc0 and 55317 D⁰ candidates. The measurement agrees with the previous LHCb measurement in 2016 [1], at -0.63σ from the measurement, using data collected in 2011-2012 of
τΩc0 = 268 ± 24 ± 10 fs,
which reorders the hierarchy of the charmed baryon lifetimes predicted in the heavy quark effective theory.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Keywords: Baryon, CERN, LHCb, lifetime, Omega, neutral, charm, flavour, physics, D0, hqet, run 2, run 1, proton proton, collision data, tau, heavy quark effective theory, pkkpi.
• Subjects: Q Science > QC Physics
• Colleges/Schools: College of Science and Engineering > School of Physics and Astronomy
• Supervisor's Name: Eklund, Professor Lars
• Date of Award: 2021
• Embargo Date: 20 November 2021
• Depositing User: Alastair Arthur
• Unique ID: glathesis:2021-82220
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 25 May 2021 13:30
• Last Modified: 25 May 2021 13:31
• Thesis DOI: 10.5525/gla.thesis.82220
• URI: https://theses.gla.ac.uk/id/eprint/82220