The object of this paper is the theta divisor of the compactiﬁed jacobian of a nodal curve. We determine its irreducible components and give it a geometric interpretation. A characterization of hyperelliptic irreducible stable curves is appended as an application.
Cite this article
Lucia Caporaso, Geometry of the theta divisor of a compactiﬁed jacobian. J. Eur. Math. Soc. 11 (2009), no. 6, pp. 1385–1427DOI 10.4171/JEMS/185