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Linearization of group stack actions and the Picard group of the moduli of $\SL_r/μ_s$-bundles on a curve

Yves Laszlo
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Abstract

We first study the descent theory of line bundles under a morphism which is tors or under a group stack and then use this technical result to determine the exact structure of $\Pic(\M_G)$ where $G=\SL_r/μ_s$ (we include a minor modification to explain the genus 0 case).

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Yves Laszlo. 1997-01-22. Linearization of group stack actions and the Picard group of the moduli of $\SL_r/μ_s$-bundles on a curve. https://arxiv.org/abs/alg-geom/9610002

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