Date of Award
Doctor of Philosophy (PhD)
CERN, CP Violation, Lambda_c Baryon, LHCb, Vcb
Physical Sciences and Mathematics | Physics
A preliminary measurement of the quark-mixing parameter |Vcb| using the exclusive decay Λ0b→ Λ+c μ−νμ is presented. A sample of Λb semileptonic decays is provided by √s = 13TeV proton-proton collisions collected by the LHCb detector in 2017. Λ0b → Λ+c μ−νμX decays are identified from muon tracks, combined with a Λc baryon. The ground state Λ0b → Λ+c μ−νμ is isolated by a fit to the Λb corrected mass spectrum. The raw yield NRaw(Λ0b → Λ+c μ−νμ) is corrected, and the semileptonic width ΓMeas. (Λ0b → Λ+c μ−νμ) is obtained. Lattice QCD calculations predict ΓTh.(Λ0b → Λ+c μ−νμ)/|Vcb|2. A comparison between the measured and predicted widths gives |Vcb| from the relative normalization. This method also provides a measurement of the branching fraction B(Λ0b → Λ+c μ−νμ) using well-measured properties of B-meson decays.
Ely, Scott Edward, "Measurement of |vcb| Using the Semileptonic Decay Λb → Λcμνμ" (2022). Dissertations - ALL. 1552.