Further Acceleration of MeV Electrons by a Relativistic Laser Pulse

With the development of photocathode rf electron gun, electrons with high-brightness and mono-energycan be obtained easily. By numerically solving the relativistic equations of motion of an electron generated from thisfacility in laser fields modelled by a circular polarized Gaussian laser pulse, we find the electron can obtain high energygain from the laser pulse. The corresponding acceleration distance for this electron driven by the ascending part of thelaser pulse is much longer than the Rayleigh length, and the light amplitude experienced on the electron is very weakwhen the laser pulse overtakes the electron. The electron is accelerated effectively and the deceleration can be neglectd.be neglected.For intensities around 10Wμm~2/cm~2 an electron’s energy gain near O.1 GeV can be realized when its initial energyis 4.5 McV, and the final velocity of the energetic electron is parallel with the propagation axis. The energy gain can beup to l GeV if the intensity is about 10W-μm~2/cm~2. The final energy gain of the electron as a function of its initialconditions and the parameters of the laser beam has also been discussed.