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arXiv · 2503.04912

The integral chow ring of $M_2^{ct}$

Joseph Helfer·Eric Jovinelly·Eric Larson·Anda Tenie·Chengxi Wang
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Abstract

This paper computes the integral Chow ring of the moduli space $M_2^{ct}$ of stable genus 2 curves of compact type. This is done by excising boundary strata from $\bar M_2$ one-by-one. During this process, we determine the Chow rings of all other open strata in $\bar M_2$ with $Z[1/2]$-coefficients.

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Joseph Helfer, Eric Jovinelly, Eric Larson, Anda Tenie, Chengxi Wang. 2025-03-06. The integral chow ring of $M_2^{ct}$. https://arxiv.org/abs/2503.04912

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