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arXiv · 1206.4301

The class of the bielliptic locus in genus 3

Carel Faber·Nicola Pagani
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Abstract

Let the bielliptic locus be the closure in the moduli space of stable curves of the locus of smooth curves that are double covers of genus 1 curves. In this paper we compute the class of the bielliptic locus in \bar{M}_3 in terms of a standard basis of the rational Chow group of codimension-2 classes in the moduli space. Our method is to test the class on the hyperelliptic locus: this gives the desired result up to two free parameters, which are then determined by intersecting the locus with two surfaces in \bar{M}_3.

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Carel Faber, Nicola Pagani. 2014-02-01. The class of the bielliptic locus in genus 3. https://arxiv.org/abs/1206.4301

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