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arXiv · 1803.05360

On the irreducible components of the compactified Jacobian of a ribbon

Michele Savarese
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Abstract

In this paper we study the irreducible components of the compactified Jacobian of a ribbon $X$ of arithmetic genus $g$ over a smooth curve $X_{\mathrm{red}}$ of genus $\bar{g}$. We prove that when $g\geq 4\bar{g}-2$ the moduli space of rank $2$ semistable vector bundles over $X_{\mathrm{red}}$ is not an irreducible component and we determine the irreducible components in which it is contained. This answers a question of D. Chen and J.L. Kass in [CK] and completes their results.

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Michele Savarese. 2018-03-14. On the irreducible components of the compactified Jacobian of a ribbon. https://doi.org/10.1080/00927872.2018.1506464

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