Published in:Physical review / D 89(5), 053015 (2014). doi:10.1103/PhysRevD.89.053015
Language:
English
DOI:
https://doi.org/10.1103/PhysRevD.89.053015
ISSN:
1550-2368;
1550-7998;
0556-2821;
1089-4918
Origination:
Footnote:
Diese Datenquelle enthält auch Bestandsnachweise, die nicht zu einem Volltext führen.
Description:
The Cabibbo-Kobayashi-Maskawa matrix element |Vub| is not well determined yet. It can be extracted from both inclusive or exclusive decays, like B→π(ρ)lν¯l. However, the exclusive determination from B→ρlν¯l, in particular, suffers from a large model dependence. In this paper, we propose to extract |Vub| from the four-body semileptonic decay B→ππlν¯l, where the form factors for the pion-pion system are treated in dispersion theory. This is a model-independent approach that takes into account the ππ rescattering effects, as well as the effect of the ρ meson. We demonstrate that both finite-width effects of the ρ meson as well as scalar ππ contributions can be considered completely in this way.