Advanced electron acceleration via chirped Hermite–Cosh–Gaussian laser and magnetic field interaction

In the present paper, we have realized the combined effect of linear frequency chirp (negative chirp) and external axial magnetic field on electron acceleration by radially polarized (RP) Hermite Cosh Gaussian (HChG) laser beam in vacuum. Electron energy gain has been analyzed by varying various laser parameters like intensity parameter ( \({\text{a}}_{0}\) ${\text{a}}_0$ ), laser spot size ( \({\text{r}}_{0}\) ${\text{r}}_0$ ), and decentered parameter ( \({\text{b}}\) $\text{b}$ ). Enhanced electron acceleration is observed with optimized value of magnetic field and frequency chirp parameter. A frequency chirp increases interaction duration between laser pulse and electron and hence, implements the resonance for longer time. The electron is accelerated with higher energy in the presence of axial magnetic field till the saturation of betatron resonance and significant results have been achieved. We have observed maximum energy \(\left( {\upgamma _{{\text{m}}} } \right)\) $\left({\mathrm{\gamma }}_{\text{m}}\right)$ gain at lower value of magnetic field (a few kG) and all other parameters are optimized. Optimistically, we can say that this theoretical study is good for low-cost future accelerators for radiation therapy.