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arXiv · 0905.1803

Rank 2 stable sheaves with odd determinant on Fano threefolds of genus 9

Maria Chiara Brambilla·Daniele Faenzi
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Abstract

By the description due to Mukai and Iliev, a smooth prime Fano threefold X of genus 9 is associated to a surface P(V), ruled over a smooth plane quartic Gamma. We use Kuznetsov's integral functor to study rank-2 stable sheaves on X with odd determinant. For each c_2 \geq 7, we prove that a component of their moduli space M_X(2,1,c_2) is birational to a Brill-Noether locus of bundles on Gamma having enough sections when twisted by V. Moreover we prove that M_X(2,1,7) is isomorphic to the blowing-up of the Picard variety Pic^2(Gamma) along the curve parametrizing lines contained in X.

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Maria Chiara Brambilla, Daniele Faenzi. 2009-05-12. Rank 2 stable sheaves with odd determinant on Fano threefolds of genus 9. https://arxiv.org/abs/0905.1803

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