English

On the group of automorphisms of Horikawa surfaces

Algebraic Geometry 2024-05-14 v2

Abstract

Minimal algebraic surfaces of general type XX such that KX2=2χ(OX)6K^2_X=2\chi(\mathcal{O}_X)-6 are called Horikawa surfaces. In this note the group of automorphisms of Horikawa surfaces is studied. The main result states that given an admissible pair (K2,χ)(K^2, \chi) such that K2=2χ6K^2=2\chi-6, every irreducible component of Gieseker's moduli space MK2,χ\mathfrak{M}_{K^2,\chi} contains an open subset consisting of surfaces with group of automorphisms isomorphic to Z2\mathbb{Z}_2.

Keywords

Cite

@article{arxiv.2201.04890,
  title  = {On the group of automorphisms of Horikawa surfaces},
  author = {V. Lorenzo},
  journal= {arXiv preprint arXiv:2201.04890},
  year   = {2024}
}

Comments

Some changes following referee's report. Final version to appear in Comptes Rendus Math\'ematique. 12 pages