The capture and acceleration of short electron bunches externally injected into wakefields generated by an intense femtosecond laser pulse in the plasma channel are studied. The injection of low-energy bunches is analyzed, which allows to obtain a substantial longitudinal bunch compression, and also to obtain the bunch energy gain to the GeV range with a small energy spread at an acceleration length of about 10 centimetres. The influence of the beam loading to the final energy and the energy spread of the accelerated electrons is investigated.
A model for numerical simulation of the acceleration of polarized electrons has been elaborated. The effect of synchrotron radiation on the dynamics of energy gain and spin precession of a polarized electron beam is investigated in the process of acceleration at the self-consistent description of the nonlinear dynamics of a laser pulse and the generated accelerating and focusing plasma wake fields. It is shown that synchrotron radiation hardly affects the energy gain and polarization of the electrons, which are accelerated in fields characteristic of the moderately nonlinear mode of laser-plasma acceleration up to an energy of 4 TeV.
The methods of preserving the electron beam quality during acceleration and transportation of particles between stages was investigated. An analytical model of the dynamics of electron beam emittance has been elaborated. Matching the beam with an initial focusing force prevents the growth of the emittance during acceleration. The scheme with a smooth exit from the accelerating stage provides a quasiadiabatic change in the emittance and polarization of the beam.
|Working group||Laser-driven electron acceleration|