  We give integral equations for the generating function of the cummulants of
the work done in a quench for the Kondo model in the thermodynamic limit. Our
approach is based on an extension of the thermodynamic Bethe ansatz to
non-equilibrium situations. This extension is made possible by use of a large
$N$ expansion of the overlap between Bethe states. In particular, we make use
of the Slavnov determinant formula for such overlaps, passing to a
function-space representation of the Slavnov matrix . We leave the analysis of
the resulting integral equations to future work.
