Abstract
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 GMp,n(t) of vector currents and those of axial ones. Explicitly, from the data of B̄0→np̄D*+ and Λp̄π+ we find a constant ratio of GMn(t)/GMp(t)=-1.3±0.4, which supports the FENICE experimental result. The vector and axial-vector form factors of pn̄, pp̄ and nn̄ pairs due to weak currents are also presented, which can be tested in future experiments. © 2007 The American Physical Society.