Resonant betatron x-ray generation using chirped laser pulses

Laser wakefield acceleration (LWFA) is an advanced technique that utilizes intense laser pulses in a plasma medium for compact electron acceleration and X-ray generation. Despite its promise, a major limitation remains: the insufficient photon flux of the produced X-rays. Addressing this issue requires innovative strategies to improve efficiency. In this study, we investigate the impact of varying the laser chirp parameter on electron acceleration and betatron X-ray production in a preformed plasma density channel. Our findings show that applying a positive chirp to the laser pulse enhances the transverse momentum of the electrons, thereby increasing both the flux and total energy of the generated X-rays. We identify an optimal positive chirp value that strengthens the resonant interaction between the laser and the electrons, ultimately maximizing the X-ray photon flux and increasing the critical energy.