Radiation reaction on a classical charged particle: a modified form of the equation of motion

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Physical Review E
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We present and numerically solve a modified form of the equation of motion for a charged particle under the influence of an external force, taking into account the radiation reaction. This covariant equation is integro differential, as Dirac-Rohrlich's, but has several technical improvements. First, the equation has the form of Newton's second law, with acceleration isolated on the left hand side and the force depending only on positions and velocities: Thus, the equation is linear in the highest derivative. Second, the total four-force is by construction perpendicular to the four-velocity. Third, if the external force vanishes for all future times, the total force and the acceleration automatically vanish at the present time. We show the advantages of this equation by solving it numerically for several examples of external force.
© 2013 American Physical Society. The authors would like to thank Norbert M. Nemes and Juan Ramirez Mittelbrunn for reading the manuscript.We also thank the constructive comments and additional references provided by the anonymous referees. This work was supported by Spanish Grants FPA2011-27853-01, FIS2008-01323 and UCM-BS GICC 910758.
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