English

Even sets of four nodes on rational surfaces

Algebraic Geometry 2007-05-23 v1

Abstract

We describe smooth rational projective algebraic surfaces X, over an algebraically closed field of characteristic different from 2, having an even set of four disjoint (-2)-curves N_1,...,N_4, i.e. such that N_1+...+N_4 is divisible by 2 in Pic(X).

Keywords

Cite

@article{arxiv.math/0407250,
  title  = {Even sets of four nodes on rational surfaces},
  author = {Alberto Calabri and Ciro Ciliberto and Margarida Mendes Lopes},
  journal= {arXiv preprint arXiv:math/0407250},
  year   = {2007}
}

Comments

9 pages

R2 v1 2026-07-22T17:07:47.866Z