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Abstract We show the effects of ladder ionization and hyperfine quenching on charge state distributions and spectral features of ions in electron beam ion trap (EBIT) devices. Ladder ionization with intermediate excitation of metastable states proceeds at lower than ionization potential electron beam energies, while hyperfine quenching reduces the lifetimes of these states by enhancing particular decay channels through nuclear-electronic coupling. Using Ni-like Pr and Nd ions, we show that these processes significantly alter ion populations and spectra, emphasizing the importance of incorporating hyperfine level specific modeling in EBIT studies. 

Maleimides serve as crucial components in various synthetic processes and are of significant interest to researchers in bioorganic chemistry and biotechnology. Although thermal reactions involving maleimides have been studied extensively, light-mediated reactions with maleimides remain relatively underutilized. This review focuses on understanding the behavior of maleimides in their excited state, particularly their role as synthetic scaffolds for excited-state reactions. Specific emphasis is placed on the diverse photoreactions involving maleimides and photophysical evaluation from our research group. 

In this work, we investigate anharmonic vibrational polaritons formed due to strong light–matter interactions in an optical cavity between radiation modes and anharmonic vibrations beyond the long-wavelength limit. We introduce a conceptually simple description of light–matter interactions, where spatially localized cavity radiation modes couple to localized vibrations. Within this theoretical framework, we employ self-consistent phonon theory and vibrational dynamical mean-field theory to efficiently simulate momentum-resolved vibrational-polariton spectra, including effects of anharmonicity. Numerical simulations in model systems demonstrate the accuracy and applicability of our approach. 

Abstract Charge-exchange recombination with neutral atoms significantly influences the ionization balance in electron beam ion traps (EBIT) because its cross section is relatively large compared to cross sections of electron collision induced processes. Modeling the highly charged ion cloud requires the estimate of operating parameters, such as electron beam energy and density, the density of neutral atoms, and the relative velocities of collision partners. Uncertainty in the charge-exchange cross section can dominate the overall uncertainty in EBIT experiments, especially when it compounds with the uncertainties of experimental parameters that are difficult to determine. We present measured and simulated spectra of few-electron Fe ions, where we used a single charge-exchange factor to reduce the number of free parameters in the model. The deduction of the charge-exchange factor from the ratio of Li-like and He-like features allows for predicting the intensity of H-like lines in the spectra.