|Vub| from Exclusive Semileptonic B to pi Decays
We use Omnes representations of the form factors f_+ and f_0 for exclusive semileptonic B to pi decays, paying special attention to the treatment of the B* pole and its effect on f_+. We apply them to combine experimental partial branching fraction information with theoretical calculations of both form factors to extract |Vub|. The precision we achieve is competitive with the inclusive determination and we do not find a significant discrepancy between our result, |Vub| =(3.90+/-0.32+/-0.18)10^(-3), and the inclusive world average value, (4.45+/-0.20+/-0.26)10^(-3).