Picard groups of the moduli spaces of semistable sheaves I USHA
نویسنده
چکیده
We compute the Picard group of the moduli space U ′ of semistable vector bundles of rank n and degree d on an irreducible nodal curve Y and show that U ′ is locally factorial. We determine the canonical line bundles of U ′ and U ′ L, the subvariety consisting of vector bundles with a fixed determinant. For rank 2, we compute the Picard group of other strata in the compactification of U ′.
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