Atkin--Lehner Quotients of Modular Curves at Primes of Bad Reduction

Lea Beneish, Boya Wen

Let $N$ be a square-free, positive integer and let $p\ge 5$ be a prime dividing $N$. In this work, we construct semistable models of Atkin--Lehner quotients of $X_0(N)$ over the Wi…