Dependence of plasma wake wave amplitude on the shape of Gaussian chirped laser pulse propagating in a plasma channel

• The generation of wakefields by a chirped Gaussian laser pulse propagating in a plasma channel has been presented.
• The influence of the asymmetry of the laser pulse on the wake wave amplitude has been study numerically.
• The results indicate that a fast rise time asymmetric positive chirped Gaussian pulses can excite a much larger wake wave.

The generation of longitudinal electrostatic plasma waves (wakefields) due to the propagation of a chirped laser pulse through a parabolic plasma channel is studied. The wakes generated by a temporally symmetric Gaussian laser pulse are compared with those generated by asymmetric one. The main interest in this paper is to investigate the effects of a laser pulse shape with of sharp rising and slow falling time scales on the excited wakefield amplitude. Moreover, positive, negative and un-chirped laser pulses are employed in numerical codes to evaluate the influence of the initial chirp on wakefield excitation. Numerical results showed that for an appropriate laser pulse length compared with the plasma wavelength, the wakefield amplitude can be enhanced for a positively chirped asymmetric Gaussian laser pulse with a fast rise time.