  Let G = SL_2(K) with K a local function field of characteristic 2. We review
Artin-Schreier theory for the field K, and show that this leads to a
parametrization of L-packets in the smooth dual of G. We relate this to a
recent geometric conjecture. The L-packets in the principal series are
parametrized by quadratic extensions, and the supercuspidal L-packets by
biquadratic extensions. We compute the formal degrees of the elements in the
supercuspidal packets.
