Rational (quasi-)elliptic surfaces with global vector fields in odd characteristic

Abstract

We classify rational elliptic and quasi-elliptic surfaces with global vector fields over arbitrary algebraically closed fields of characteristic $p\ge 0$ different from $2$. For every such surface, we determine the multiple and reducible fibers, the identity component of the automorphism scheme, and the moduli. As a corollary, we deduce that rational (quasi-)elliptic surfaces with global vector fields are Jacobian if $p\ne 3,5$ and we describe all counterexamples in small characteristics.

arXiv comment39 pages, comments welcome