Hyperelliptic Atkin-Lehner quotients of Shimura curves

Abstract

We work towards completely classifying all hyperelliptic Atkin-Lehner quotients of Shimura curves $X_0(D,N)/W$ with level $N$ coprime to $D$ and $W \le W_0(D,N)$, extending, on the one hand, a result of Ogg that provided such a classification for the trivial quotients (the case $W = 1$), and on the other hand, results of Furumoto and Hasegawa that provided such a classification for modular curves (the case $D = 1$). As a byproduct of our methods, building on the works of Guo and Yang, we also obtain models for some quotients of genus at most two, answering some questions of Padurariu and Saia.