  We study the plasmon mass scale in weakly coupled strongly interacting
nonabelian gauge theory in a two dimensional configuration that mimics the
boost invariant initial color fields in a heavy ion collision. We numerically
measure the plasmon mass scale using three different methods: a Hard Thermal
Loop (HTL) expression involving the quasiparticle spectrum constructed from
Coulomb gauge field correlators, an effective dispersion relation and the
measurement of oscillations between electric and magnetic energies after
introducing a spatially uniform perturbation to the electric field. We find
that the hard thermal loop expression and the uniform electric field
measurement are in rough agreement. The effective dispersion relation agrees
with other methods within a factor of two. We also study the dependence on time
and occupation number, observing similar trends as in three spatial dimensions,
where a power law dependence sets in after an occupation number dependent
transient time. We observe a decrease of the plasmon mass squared as
$t^{\frac{-1}{3}}$ at late times.
