Semistable models of elliptic curves over residue characteristic 2

Abstract

Given an elliptic curve $E$ in Legendre form $y^2 = x(x - 1)(x - \lambda)$ over the fraction field of a Henselian ring $R$ of mixed characteristic $(0, 2)$, we present an algorithm for determining a semistable model of $E$ over $R$ which depends only on the valuation of $\lambda$. We provide several examples along with an easy corollary concerning $2$-torsion.