Applicability Conditions for the Approximation Presuming Small Influence of Radiation Damping on the Motion of a Classical Electron in the Field of a Monochromatic Plane Wave

摘要

We consider the motion of a classical electron in the field of a monochromatic plane wave of an arbitrary (linear, circular, or elliptic) polarization in an arbitrary inertial reference system. It is shown that the ratio of the energy emitted by an electron moving with acceleration in the field of the wave during the time equal to its period to the mean energy of the oscillatory motion of the electron can be expressed in terms of two dimensionless relativistic invariant parameters. As the criterion determining the applicability limit of the approximation presuming a small influence of the radiation damping on the motion of the classical electron in the field of the monochromatic plane wave, we consider the condition of equality of energy emitted by the electron during the period and the mean energy of the oscillatory motion. The applicability boundary of the approximation is constructed in the space of two dimensionless invariant parameters. In the reference system in which the electron has been at rest prior to the arrival of a wave with a sharp leading edge, one of these parameters is proportional to the frequency of the incident wave, while the other, to its intensity.