  We study base points of the generalized Theta-divisor on the moduli space of
vector bundles on a smooth algebraic curve X of genus g defined over an
algebraically closed field. To do so, we use the derived categories D(Pic(X)),
D(Jac(X)), and the equivalence between them given by the Fourier-Mukai
transform coming from the Poincar\'e bundle. The vector bundles P(m) on the
curve X defined by Raynaud play a central role in this description. Indeed, we
show that a vector bundle E is a base point of the generalized Theta-divisor,
if and only if there exists a nontrivial homomorphism P(rk(E)g+1) --> E.

Algebraic Geometry