Laser-based K α X-ray emission characterization using a high contrast ratio and high-power laser system

Abstract

We characterized a laser-based \(K_\alpha\) X-ray source produced onto a Mo solid target. We used a laser system with a high laser pulse contrast ratio (LPCR) and an instantaneous power \(\sim\)30 TW. We investigated simultaneously the \(K_\alpha\) X-ray conversion efficiency, the X-ray source size, and the proton front surface emission. We found a high \(K_\alpha\) X-ray conversion efficiency up to \(2\times 10^{-4}\) associated with an X-ray source size only \(\sim\)1.8 times larger than the laser focal spot for the highest intensities. We found that using a high LPCR laser pulse with 245 mJ per pulse is of interest to develop a laser-based X-ray imaging system as it can combine a high conversion efficiency with a small increase in the X-ray source size compared to the laser focal spot.