Department
Physics
Document Type
Article
Publication Date
1-2018
Embargo Period
7-3-2018
Abstract
With the full data sample of 772×106 B¯B pairs recorded by the Belle detector at the KEKB electron-positron collider, the decay ¯B→D∗τ−¯ντ is studied with the hadronic τ decays τ−→π−ντ and τ−→ρ−ντ. The τ polarization Pτ(D∗) in two-body hadronic τ decays is measured, as well as the ratio of the branching fractions R(D∗)=B(¯B→D∗τ−¯ντ)/B(¯B→D∗ℓ−¯νℓ), where ℓ− denotes an electron or a muon. Our results, Pτ(D∗)=−0.38±0.51(stat)+0.21−0.16(syst) and R(D∗)=0.270±0.035(stat)+0.028−0.025(syst), are consistent with the theoretical predictions of the standard model. The polarization values of Pτ(D∗)>+0.5 are excluded at the 90% confidence level.
Journal Title
Physical Review D
Journal ISSN
2470-0010
Volume
97
Issue
1
Digital Object Identifier (DOI)
10.1103/PhysRevD.97.012004
Comments
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.