Simpson Jacobians of Reducible Curves
نویسنده
چکیده
For any projective curve X let M d (X) be the Simpson moduli space of pure dimension one rank 1 degree d sheaves that are semistable with respect to a fixed polarization H on X . When X is a reduced curve the connected component of M d (X) that contains semistable line bundles can be considered as the compactified Jacobian of X . 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 III, IV and IN with N ≥ 2
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