(1) Tata Institute of Fundamental Research, Homi Bhabha Road, 400 005 Mumbai, India
Abstract:
We compute the Picard group of the moduli spaceU′ of semistable vector bundles of rankn and degreed on an irreducible nodal curveY and show thatU′ is locally factorial. We determine the canonical line bundles ofU′ andUL′, the subvariety consisting of vector bundles with a fixed determinant. For rank 2, we compute the Picard group of other strata
in the compactification ofU′.