Study of exclusive B→Xuℓν decays and extraction of |Vub| using full reconstruction tagging at the Belle experiment

By Belle Collaboration A. Sibidanov, K. Varvell, I. Adachi, H. Aihara, D. Asner, V. Aulchenko, T. Aushev, A. Bakich, A. Bala, A. Bozek and 158 more. 2013

141 citations recorded by the source corpus.

We report the results of a study of the exclusive semileptonic decays B-→π0l-ν¯l, B¯0→π+l-ν¯l, B-→ρ0l-ν¯l, B¯0→ρ+l-ν¯l and B-→ωl-ν¯l, where l represents an electron or a muon. The events are tagged by fully reconstructing a second B meson in the event in a hadronic decay mode. The measured branching fractions are B(B-→π0l-ν¯l)=(0.80±0.08±0.04)×10-4, B(B¯0→π+l-ν¯l)=(1.49±0.09±0.07)×10-4, B(B-→ρ0l-ν¯l)=(1.83±0.10±0.10)×10-4, B(B¯0→ρ+l-ν¯l)=(3.22±0.27±0.24)×10-4, and B(B-→ωl-ν¯l)=(1.07±0.16±0.07)×10-4, where the first error is statistical and the second one is systematic. The obtained branching fractions are inclusive of soft photon emission. We also determine the branching fractions as a function of the 4-momentum transfer squared to the leptonic system q2=(pl+pν)2, where pl and pν are the lepton and neutrino 4-momenta, respectively. Using the pion modes, a recent light cone sum rule calculation, lattice QCD results and a model-independent description of the hadronic form factor, a value of the Cabibbo-Kobayashi-Maskawa matrix element |Vub|=(3.52±0.29)×10-3 is extracted. A structure in the two-pion invariant mass distribution near 1.3 GeV/c2, which might be dominated by the decay B-→f2(1270)l-ν¯l, f2→π+π-, is seen. These results are obtained from a 711 fb-1 data sample that contains 772×106 BB¯ pairs, collected near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.

Subfields: Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/703bb5ee932dfcffaaad41bd1f94935cd4bd97a0

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Nuclear and High Energy Physics

Citations in the corpus

B →Vℓ+ℓ− in the Standard Model from light-cone sum rules (2015, methodology): “Figure 4: Our predictions for |Vub| from B → ρ`ν and B → ω`ν (blue) compared to global fits to Vub from exclusive [80] and inclusive channels [89] and indirect determinations from fits of the unitarity triangle [93,94].”
FLAG Review 2019 (2019, background): “The available state-of-the-art experimental input consists of five data sets: three untagged measurements by BaBar (6-bin [640] and 12-bin [641]) and Belle [642], all of which assume isospin symmetry and provide combined B0 → π− and B+ → π0 data; and the two tagged Belle measurements of B̄0 → π+ (13”
Determination of the quark coupling strength |Vub| using baryonic decays (2015, result): “This can be compared to the latest |Vub| determinations from B ! ⇡l ⌫̄l decays by the BaBar and Belle experiments which used data samples containing respectively 462 million [6] and 772 million [9] BB̄ pairs collected from ee collisions at the ⌥(4s) resonance.”
Review of lattice results concerning low-energy particle physics (2016, background): “, by HFAG, consists of five datasets: three untagged measurements by BaBar (6-bin [548] and 12-bin [438]) and Belle [437], all of which assume isospin symmetry and provide combined B0 → π− and B+ → π0 data; and the two tagged Belle measurements of B̄0 → π+ (13-bin) and B− → π0 (7-bin ) [549].”