# High charge plasma electron bunches from two collinear laser pulses

## TL;DR

This paper investigates a laser wakefield acceleration scheme using two collinear laser pulses, demonstrating the generation of ultra-short, high-charge electron bunches suitable for advanced radiation sources and applications.

## Contribution

It introduces a localized injection method with two collinear pulses, achieving high-charge, ultra-short electron bunches with potential for various high-intensity applications.

## Key findings

- Generation of 6 fs, hundred-pC electron bunches
- Optimal injection at plasma wavelength intersection
- Localized injection enhances charge and control

## Abstract

An optical injection scheme into the laser wakefield accelerator by preceding injection pulse is investigated by means of 3D numerical particle-in-cell simulations. Quasimonoenergetic hundred-pC electron bunches as short as 6 fs can be generated. Optimal beam separation distance is found at the intersection point of the injection beam bubble with the collection volume for transverse injection into the accelerator beam bubble. It approximately corresponds to the plasma wavelength. The main advantage of this scheme is the localized injection of high charge. This injection mechanism can be useful for applications such as ultrashort and relatively intense X-ray radiation sources such as a betatron radiation or Thomson backscattering, time-resolved electron diffraction or for seeding of further acceleration stages.