Hyperon decay form factors in chiral perturbation theory

We present a complete calculation of the SU(3)-breaking corrections to the hyperon vector form factors up to O(p(4)) in covariant baryon chiral perturbation theory. Partial higher-order contributions are obtained, and we discuss chiral extrapolations of the vector form factor at zero momentum transfer. In addition we derive low-energy theorems for the subleading moments in hyperon decays, the weak Dirac radii and the weak anomalous magnetic moments, up to O(p(4))