Acceleration of electrons by high intensity laser radiation in a magnetic field

Abstract

We consider the acceleration of electrons in vacuum by means of the circularly-polirized electromagnetic wave, propagating along a magnetic field. We show that the electron energy growth, when using ultrashort and ultra-intense laser pulses (1 ps, 10 18 W/cm 2 , CO 2 laser) in the presence of a magnetic field, may reach up to the value 2, 1 Gev. The growth of the electron energy is shown to increase proportionally with the increase of the laser intensity and the initial energy of the electron. We find that for some direction of polarization of the wave, the acceleration of electrons does not depend on the initial phase of the electromagnetic wave. We estimate the laser intensity, necessary for the electron acceleration. In addition, we find the formation length of photon absorption by electrons, due to which one may choose the required region of the interaction of the electrons with the electromagnetic wave and magnetic field. We also show that as a result of acceleration of electrons in the vacuum by laser radiation in a magnetic field one may obtain electron beam with small energy spread of the order δǫ /ǫ ≤ 10 −2 .

Combined influence of azimuthal and axial magnetic fields on resonant electron acceleration in plasma

“…The combined influence of frequency chirp and azimuthal magnetic field has been studied, employing linearly and circularly polarized lasers, and it is reported that the combined effect of chirping and azimuthal magnetic field not only enhances the electron energy gain, but retains this electron energy gain for longer distances [20,23]. Results have shown that small energy spread of the order δε/ε 10 −2 is obtained by laser induced electron acceleration in vacuum in magnetic field [21].…”