Emission and dose characterization of the 1 kHz repetition rate high-Z metal K $$_{\alpha }$$ α source driven by 20 mJ femtosecond pulses

Abstract

We present the hard X-ray generation of K $$_{\alpha }$$ 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 K $$_{\alpha _{1}}$$ X-ray photon flux from the recorded spectrum was 1.3 $$\times$$ 10 $$^{7}$$ and 1.4 $$\times$$ 10 $$^{7}$$ photons/s, respectively, in 2 $$\pi$$ solid angle. The calculated values of the photon conversion efficiency were 1.3 $$\times$$ 10 $$^{-8}$$ for Pt K $$_{\alpha _{1}}$$ and 9 $$\times$$ 10 $$^{-9}$$ for W K $$_{\alpha _{1}}$$ . 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 $$\upmu$$ Sv/h was measured on the top of the X-ray generation chamber.