Stacks of uniform cyclic covers of curves and their Picard groups

Flavia Poma; Mattia Talpo; Fabio Tonini

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arXiv · 1312.5675

Stacks of uniform cyclic covers of curves and their Picard groups

Flavia Poma·Mattia Talpo·Fabio Tonini

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Abstract

We study the stack B_{h,g,n} of uniform cyclic covers of degree n between smooth curves of genus h and g and, for h >> g, present it as an open substack of a vector bundle over the universal Jacobian stack of M_g. We use this description to compute the integral Picard group of B_{h,g,n}, showing that it is generated by tautological classes of B_{h,g,n}.

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BibTeX RIS

Flavia Poma, Mattia Talpo, Fabio Tonini. 2017-03-16. Stacks of uniform cyclic covers of curves and their Picard groups. https://arxiv.org/abs/1312.5675

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