On the Neron-Severi group of Jacobians of curves with automorphisms
Let \(C\) be a smooth projective complex curve with a cyclic group of automorphisms of prime order. By using the well-known isomorphism between NS(J) (the Neron-Severi group of the jacobian of \(C)\) and the invariant part (under the Rosati involution) of its ring of endomorphisms, the author gives a geometric description of certain elements of NS(J) which allows him to estimate rank NS(J) from below. Then the author proves the main result which asserts that under certain hypotheses, about the eigenspaces of the space of holomorphic differentials, those found elements span NS(J).
scientific article; zbMATH DE number 510028