Determination of nucleon form factors from baryonic B decays

It is the first time that the study of three-body baryonic B decays offers an independent determination of the nucleon form factors for the timelike four momentum transfer (t>0) region, such as G{sub M}{sup p,n}(t) of vector currents and those of axial ones. Explicitly, from the data of B{sup 0}{yields}npD*{sup +} and {lambda}p{pi}{sup +} we find a constant ratio of G{sub M}{sup n}(t)/G{sub M}{sup p}(t)=-1.3{+-}0.4, which supports the FENICE experimental result. The vector and axial-vector form factors of pn, pp and nn pairs due to weak currents are also presented, which can be tested in future experiments.