First vertices for generic Newton polygons, and -cyclic coverings of the projective line
arXiv:0912.2051
Abstract
In this paper we compute the first vertex of a generic Newton polygon in some special cases, and the corresponding Hasse polynomial. This allows us to show the nonexistence of -cyclic coverings of the projective line in characteristic with supersingular jacobian for some (infinite families of) genera.
partial results, comments welcome