Semi-leptonic B decays and the two-pion distribution amplitudes

摘要

We show that the semi-leptonic decay B~+ → π~+π~-l_(vl)~+ can be used as a source of information for two-pion distribution amplitudes. The connection between these amplitudes and the B-meson decay width is achieved by the light cone sum rule method. We show the relevant distribution amplitudes and give the formula for the decay width.