Precision Model Independent Determination of |Vub| from B→πlν

A precision method for determining |V_ub| using the full range in q² of B→πℓν data is presented. At large q² the form factor is taken from unquenched lattice QCD, at q²=0 we impose a model independent constraint obtained from B→ππ using the soft-collinear effective theory, and the shape is constrained using QCD dispersion relations. We find |V_ub|=(3.54±0.17±0.44)×10^-3. With 5% experimental error and 12% theory error, this is competitive with inclusive methods. Theory error is dominated by the input points, with negligible uncertainty from the dispersion relations.