Speaker
Description
Laser wakefield acceleration (LWFA) can generate compact relativistic electron beams, but its performance is often limited by uncontrolled self-injection. In this work, we use quasi-3D Smilei particle-in-cell simulations to study nanoparticle-assisted injection in helium plasma with lithium, aluminium, and copper nanoparticles. These nanoparticles act as localized plasma perturbations that modify the injection dynamics, producing material-dependent regimes ranging from weak perturbation to enhanced injection. We then focus on lithium, distinguishing helium plasma electrons injected by the nanoparticle-triggered wake from electrons born directly from the nanoparticle. Further optimization of the lithium case produces keV-range betatron X-ray emission and, to our knowledge, represents the first study of betatron radiation in nanoparticle-assisted LWFA. These results not only show that nanoparticles can control electron beam injection and quality,but also suggest a promising path toward reliable compact plasma-based X-ray generation for multidisciplinary applications.