Semileptonic hyperon decays on the lattice: an exploratory study

We present preliminary results of an exploratory lattice study of the vector form factor f(1)(q(2) = 0) relevant for the semileptonic hyperon decay Sigma(-) --> n l v. This study is based on the same method used for the extraction of f(+)(0) for the decay K-0 --> pi(-) l v. The main purpose of this study is to test the method for hyperon form factors in order to estimate the precision that can be reached and the importance of SU(3)-breaking effects.