Canonical coverings of Enriques surfaces in characteristic $2$

Abstract

Let $\bar{Y}$ be a normal surface that is the canonical ${\mu }_2$- or ${\alpha }_2$-covering of a classical or supersingular Enriques surface in characteristic $2$. We determine all possible configurations of singularities on $\bar{Y}$, and for each configuration we describe which type of Enriques surfaces (classical or supersingular) appear as quotients of $\bar{Y}$.

comments welcome / v2 contains several new results: the case of elliptic double point singularity is taken into consideration, and the description of 1-dimensional family of Enriques quotients is added / v3 (23 pages) minor revision, former Section 2 split into Sections 2 and 3

References in corpus (1)

• A 1-dimensional family of Enriques surfaces in characteristic 2 covered by the supersingular K3 surface with Artin invariant 1

Cited by in corpus (1)

• Coble surfaces in characteristic two