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arXiv · 1510.07401

Divisors on Hurwitz spaces: an appendix to 'The cycle classes of divisorial Maroni loci'

Gerard van der Geer·Alexis Kouvidakis
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Abstract

The Maroni stratification on the Hurwitz space of degree $d$ covers of genus $g$ has a stratum that is a divisor only if $d-1$ divides $g$. Here we construct a stratification on the Hurwitz space that is analogous to the Maroni stratification, but has a divisor for all pairs $(d,g)$ with $d \leq g$ with a few exceptions and we calculate the divisor class of an extension of these divisors to the compactified Hurwitz space.

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Gerard van der Geer, Alexis Kouvidakis. 2015-10-26. Divisors on Hurwitz spaces: an appendix to 'The cycle classes of divisorial Maroni loci'. https://arxiv.org/abs/1510.07401

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