Emission and dose characterization of the 1 kHz repetition rate high-Z metal K _α source driven by 20 mJ femtosecond pulses

We present the hard X-ray generation of K _α lines in high-Z elements – platinum and tungsten – targets using the kHz repetition rate TW-class 850 nm, 10 fs laser pulses. The estimated Pt and W Kα1 X-ray photon flux from the recorded spectrum was 1.3 × 10 ⁷ and 1.4 × 10 ⁷  photons/s, respectively, in 2π solid angle. The calculated values of the photon conversion efficiency were 1.3 × 10 ^{- 8} for Pt Kα1 and 9 × 10 ^{- 9} for W Kα1. The additional experimental bremsstrahlung-induced dose measurements and modeling were performed. The correspondence between experimental and modeling data for the dose evaluation was found. The dose rate up to 25 μ Sv/h was measured on the top of the X-ray generation chamber.