An atomic transition pertaining to a sub-valence electron, driven by chaotic SASE-FEL pulses G M Nikolopoulos P Lambropoulos 10.6084/m9.figshare.1012381.v1 https://iop.figshare.com/articles/figure/_An_atomic_transition_pertaining_to_a_sub_valence_electron_driven_by_chaotic_SASE_FEL_pulses/1012381 <p><strong>Figure 4.</strong> An atomic transition pertaining to a sub-valence electron, driven by chaotic SASE-FEL pulses. The resulting inner-shell vacancy in the excited atom decays with rate Γ<sub>2</sub>.</p> <p><strong>Abstract</strong></p> <p>Motivated by recent experiments pertaining to the interaction of weak SASE-free-electron-laser (FEL) pulses with atoms and molecules, we investigate the conditions under which such interactions can be described in the framework of a simple phase-diffusion model with decorrelated atom–field dynamics. The nature of the fluctuations that are inevitably present in SASE-FEL pulses is shown to play a pivotal role in the success of the decorrelation. Our analysis is performed in connection with specific recent experimental results from FLASH in the soft x-ray regime.</p> 2013-08-13 00:00:00 pulse flash fel interaction Atomic Physics Molecular Physics