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arXiv · 2104.06883

Coherent systems and BGN extensions on nodal reducible curves

Sonia Brivio·Filippo F. Favale
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Abstract

Let $(C,\underline{w})$ be a polarized nodal reducible curve. In this paper we consider coherent systems of type $(r,d,k)$ on $C$ with $k < r$. We prove that the moduli spaces of $(\underline{w},\alpha)$-stable coherent systems stabilize for large $\alpha$ and we generalize several results known for the irreducible case when we chose a good polarization. Then, we study in details the components of moduli spaces containing coherent systems arising from locally free sheaves.

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Sonia Brivio, Filippo F. Favale. 2021-04-14. Coherent systems and BGN extensions on nodal reducible curves. https://doi.org/10.1142/s0129167x22500276

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