Artin-Schreier-Witt extensions and ramification breaks

G. Griffith Elder, Kevin Keating

Let $K=k((t))$ be a local field of characteristic $p>0$, with perfect residue field $k$. Let $\vec{a}=(a_0,a_1,\dots ,a_{n-1})\in W_n(K)$ be a Witt vector of length $n$. Artin-Schre…