X-ray spectroscopic study of stopping dynamics for Ca$^{6+}$ ion in an aerogel target

Variation of the velocity of Ca$^{6+}$ ions with initial energies of 5.9 and 11.4 MeV/nucleon has been experimentally studied in the course of ion stopping in a solid aerogel target. The method is based on measuring the Doppler shift in the $K$-shell spectrum of decelerated Ca$^{19+}$ and Ca$^{18+}$ ions. High spatial resolution (30-50 mm) in the direction of the ion beam propagation achieved simultaneously with high spectral resolution ($\lambda/\Delta \lambda=1000\div 3000$) in the X-ray wavelength interval of $2\div 4$ Å allowed the ion beam dynamics in the solid target to be directly measured. By measuring variations in the relative intensity of spectral lines, it is possible to monitor the redistribution of the ions over charged states during their motion in the target.