Compactification of the Prym Map for Non Cyclic Triple Coverings
نویسندگان
چکیده
According to [LO], the Prym variety of any non-cyclic étale triple cover f : Y → X of a smooth curve X of genus 2 is a Jacobian variety of dimension 2. This gives a map from the moduli space of such covers to the moduli space of Jacobian varieties of dimension 2. We extend this map to a proper map Pr of a moduli space S3M̃2 of admissible S3-covers of genus 7 to the moduli space A2 of principally polarized abelian surfaces. The main result is that Pr : S3M̃2 → A2 is finite surjective of degree 10.
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