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

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 نشر من قبل Gerard van der Geer
 تاريخ النشر 2015
  مجال البحث
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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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