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First Lattice Study of the Form Factors A_0 and A_3 in the Decay Bbar^0 to rho^+ l^- nubar_l

UKQCD Collaboration·J M Flynn·J Nieves
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Abstract

We report on a lattice calculation of the form factors A_0 and A_3 for the pseudoscalar to vector meson semileptonic decay Bbar^0 to rho^+ l^- nubar_l. We find that resonant (or pole-type) contributions alone are unable to describe these two form factors simultaneously. For the quantity A_0(q^2=0), which is important phenomenologically for the determination of |Vub|, we extract a range of values, A_0(q^2=0) = (0.16--0.35) +0.09-0.06, where the range is due to systematic uncertainty and the quoted error is statistical. We have also determined A_2(q^2=0) = 0.28 +0.09-0.06 +0.04-0.05.

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UKQCD Collaboration, J M Flynn, J Nieves. 1996-02-01. First Lattice Study of the Form Factors A_0 and A_3 in the Decay Bbar^0 to rho^+ l^- nubar_l. https://doi.org/10.1016/0550-3213(96)00307-0

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