English

Simpson Jacobians of reducible curves

Algebraic Geometry 2007-05-23 v1

Abstract

For any projective curve XX let Mˉd(X)\bar{M}^d(X) be the Simpson moduli space of pure dimension one rank 1 degree dd sheaves that are semistable with respect to a fixed polarization HH on XX. When XX is a reduced curve the connected component of Mˉd(X)\bar{M}^d(X) that contains semistable line bundles can be considered as the compactified Jacobian of XX. In this paper we give explicitly the structure of this compactified Simpson Jacobian for the following projective curves: tree-like curves and all reduced and reducible curves that can appear as Kodaira singular fibers of an elliptic fibration, that is, the fibers of types IIIIII, IVIV and INI_N with N2N\geq 2

Keywords

Cite

@article{arxiv.math/0410393,
  title  = {Simpson Jacobians of reducible curves},
  author = {Ana Cristina Lopez},
  journal= {arXiv preprint arXiv:math/0410393},
  year   = {2007}
}

Comments

Latex file with 13 figures. Final version to appear in J. Reine. Angew. Math