Vector bundles on Fano threefolds of genus 7 and Brill-Noether loci

Given a smooth prime Fano threefold $X$ of genus 7 we consider its homologically projectively dual curve $Γ$ and the natural integral functor $Φ^{!}:D^b(X) \to D^b(Γ)$. We prove that, for $d\geq 6$, $Φ^{!}$ gives a birational map from a component of the moduli scheme $M_X(2,1,d)$ of rank 2 stable sheaves on $X$ with $c_1=1$, $c_2=d$ to a generically smooth $2d-9$-dimensional component of the Brill-Noether variety $W^{2d-11}_{d-5,5d-24}$ of stable vector bundles on $Γ$ of rank $d-5$ and degree $5d-24$ with at least $2d-10$ sections. This map turns out to be an isomorphism for $d=6$, and the moduli space $M_X(2,1,6)$ is fine. For general $X$, this moduli space is a smooth irreducible threefold.

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