DIVISORS ON HURWITZ SPACES: AN APPENDIX TO 'THE CYCLE CLASSES OF DIVISORIAL MARONI LOCI'

摘要

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 <= g with a few exceptions and we calculate the divisor class of an extension of these divisors to the compactified Hurwitz space.