  We report an exact solution of the Hartemann-Luhmann equation of motion for a
charged particle interacting with an intense electromagnetic wave/pulse. It is
found that the radiation reaction force has a significant affect on the charged
particle dynamics and the particle shows, on average, a net energy gain over a
period of time. Further, using a MATHEMATICA based single particle code, the
net energy gained by the particle is compared with that obtained using
Landau-Lifshitz and Ford-O'connell equation of motion, for different
polarizations of the electromagnetic wave. It is found that the average energy
gain is independent of both the chosen model equation and polarization of the
electromagnetic wave. Our results thus show, that the simpler and hence
analytically tractable Hartemann-Luhmann equation of motion ( as compared to
Landau-Lifshitz and Ford-O'connell equation of motion) is adequate for
calculations of practical use (for e.g. energy calculation).
