Simple model for sequential multiphoton ionization by ultraintense x rays

The beam transport system for the Small Quantum Systems instrument at the European XFEL: optical layout and first commissioning results

“…It uses the beam from the SASE3 soft X-ray undulator between the carbon and argon K edges, in the range 260-3200 eV. The instrument, described in detail by Mazza et al (2012) and Meyer et al (2023), was commissioned in 2018 (Meyer et al, 2023) and the results of the first successful user experiments have been published (Kastirke et al, 2020a,b;Eichmann et al, 2020;Mazza et al, 2020;LaForge et al, 2021;Jahnke et al, 2021;Li et al, 2021Li et al, , 2022aBoll et al, 2022;Feinberg et al, 2022). Experiments at the SQS instrument exploit the intense, short and coherent X-ray pulses for nonlinear phenomena studies (Mazza et al, 2020;Eichmann et al, 2020;LaForge et al, 2021;Boll et al, 2022), for time-resolved experiments following dynamical processes on the femtosecond timescale (Kastirke et al, 2020b;Jahnke et al, 2021;Grychtol et al, 2021;Rivas et al, 2022) and for investigations using coherent scattering techniques (Ekeberg et al, 2022;Feinberg et al, 2022).…”