2000/06/07 by Matthias Neubert · 31 citations
Physics and Astronomy · #Hadron #High-Energy Particle Collisions Research #Invariant (physics) #Invariant mass #Lepton #Mass spectrometry #Mass spectrum #Mathematical physics #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Quark #Semileptonic decay #hep-ph
paper · pdf · doi:10.1088/1126-6708/2000/07/022
published in Journal of High Energy Physics 2000(07), 022 (Springer Nature) · 19 pages, 8 figures
arxiv created 2000/06/07 · openalex publication_date 2000/07/13 · arxiv updated 2014/11/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Bauer, Ligeti and Luke have recently proposed a new method for measuring |Vub| in inclusive semileptonic B decays, using a cut on the lepton invariant mass to discriminate against b->c transitions. We investigate the structure of the heavy-quark expansion for this case and show that to all orders the magnitude of the leading perturbative and nonperturbative corrections is controlled by a hadronic scale muc=O(mc) depending on the minimal value of q2. These corrections can be analyzed using a modified version of the heavy-quark expansion (``hybrid expansion''). We find that the theoretical uncertainty in the extraction of |Vub| is a factor 2.5 larger than previously estimated, which allows for a determination with 10% accuracy.