Exact analysis of particle dynamics in combined field of finite duration laser pulse and static axial magnetic field

Abstract

Dynamics of a charged particle is studied in the field of a relativistically intense linearly polarized finite duration laser pulse in the presence of a static axial magnetic field. For a finite duration laser pulse whose temporal shape is defined by Gaussian profile, exact analytical expressions are derived for the particle trajectory, momentum, and energy as function of laser phase. From the solutions, it is shown that, unlike for the monochromatic plane wave case, resonant phase locking time between the particle and laser pulse is finite. The net energy transferred to the particle does not increase monotonically but tends to saturate. It is further shown that appropriate tuning of cyclotron frequency of the particle with the characteristic frequency in the pulse spectrum can lead to the generation of accelerated particles with variable energies in MeV-TeV range.

Effect of radiation-reaction on charged particle dynamics in a focused electromagnetic wave

“…ω B ≥ ω . One striking result of this study was, that a charged particle does not gain any energy from a transverse electromagnetic wave [2][3][4] . This may be understood from the underlying mechanism of charged particle acceleration in a transverse electromagnetic wave, which is the following.…”

“…when the cyclotron frequency of the particle in the external magnetic field matches the Doppler shifted frequency of the wave seen by the particle. This is the well known auto-resonant particle acceleration scheme [5][6][7] , where one of the constants of motion viz. the perpendicular component of canonical momentum is not conserved.…”

Polarization effects in cosmic-ray acceleration by cyclotron autoresonance

“…Here, the role that could be played in CARA by polarization of the radiation field is investigated [22][23][24][25]. Issues regarding plausibility of the classical approach, radiation loss, and the radiation-reaction effects, will all be left out as they have been discussed elsewhere [16].…”

Radiation reaction effect on laser driven auto-resonant particle acceleration

“…couples the particle dynamics along the transverse spatial components and decoupling of the motion yields driven harmonic oscillator equations along these components [25,27]. The oscillators are driven by externally applied field of laser together with the static axial magnetic fields.…”

“…The previous studies[ [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]] on the topic have not considered the effect of radiation reaction in this scheme. The radiation reaction (or radiative friction) is a recoil force acting on the accelerating (retarding) particle as a result of emission of radiation and can in turn influence the motion of the particle.…”