The congruence subgroup property for the hyperelliptic modular group: the open surface case

Marco Boggi

Let ${\mathcal{M}}_{g,n}$ and ${\mathcal{H}}_{g,n}$, for $2g-2+n>0$, be, respectively, the moduli stack of $n$-pointed, genus $g$ smooth curves and its closed substack consisting of hyperell…