Published 2024 | Version v1
Journal article

Updates on the determination of |Vcb|, R(D*) and |Vub|/|Vcb|

  • 1. INFN Sezione di Roma La Sapienza, Rome (Italy)
  • 2. Physics Department, Rome (Italy)
  • 3. Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tre, Rome (Italy)
  • 4. LAPTh, Université Savoie Mont-Blanc et CNRS, Annecy (France)

Description

We present an updated determination of the values of |Vcb|, R(D*) and |Vub|/|Vcb| based on the new data on semileptonic B → D*ℓν decays by the Belle and Belle-II Collaborations and on the recent theoretical progress in the calculation of the form factors relevant for semileptonic B → D*ℓν and Bs → Kℓν decays. In particular we present results derived by applying either the Dispersive Matrix (DM) method of Di Carlo et al. (Phys Rev D 104:054502, 2021), Martinelli et al. (Phys Rev D 104:094512, 2021), Martinelli et al. (Phys Rev D 105:034503, 2022), Martinelli et al. (Eur Phys J C 82:1083, 2022), Martinelli et al. (JHEP 08:022, 2022) and Martinelli et al. (Phys Rev D 106:093002, 2022) or the more standard Boyd-Grinstein-Lebed (BGL) (Boyd et al. in Phys Rev D 56:6895, 1997) approach to the most recent values of the form factors determined in lattice QCD. Using all the available lattice results for the form factors from the DM method we get the theoretical value Rth(D*) = 0.262 ± 0.009 and we extract from a bin-per-bin analysis of the experimental data the value |Vcb| = (39.92 ± 0.64) · 103. Our result for R(D*) is consistent with the latest experimental world average Rexp(D*) = 0.284 ± 0.012 (HFLAV Collaboration in Preliminary average of R(D) and R(D*) as for Summer 2023. See https://hflav-eos.web.cern.ch/hflav-eos/semi/summer23/html/RDsDsstar/RDRDs.html) at the 1.5σ level. Our value for |Vcb| is compatible with the latest inclusive determinations |Vcb|incl = (41.97 ± 0.48) · 103 (Finauri and Gambino in The q2 moments in inclusive semileptonic B decays. arXiv:2310.20324) and |Vcb|incl = (41.69 ± 0.63) · 103 (Bernlochner et al. in JHEP 10:068, 2022) within 2.6 and 2.0 standard deviations, respectively. From a reappraisal of the calculations of |Vub|/|Vcb|, we also obtain |Vub|/|Vcb| = 0.087 ± 0.009 in good agreement with the result |Vub|/|Vcb| = 0.0844± 0.0056 from the latest FLAG review (Flavour Lattice Averaging Group (FLAG) Collaboration in Phys J C 82:869, 2022).

Availability note (English)

Available from: http://dx.doi.org/10.1140/epjc/s10052-024-12742-5

Additional details

Publishing Information

Journal Title
European Physical Journal. C, Particles and Fields (Online)
Journal Volume
84
Journal Issue
4
Journal Page Range
vp.
ISSN
1434-6052
CODEN
EPCFFB

INIS

Country of Publication
Germany
Country of Input or Organization
Germany
INIS RN
56000667
Subject category
S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
Descriptors DEI
FORM FACTORS; PARTICLE DECAY; QUANTUM CHROMODYNAMICS
Descriptors DEC
DECAY; DIMENSIONLESS NUMBERS; FIELD THEORIES; PARTICLE PROPERTIES; QUANTUM FIELD THEORY

Optional Information

Notes
AID: 400