Studies of the Kα X-ray spectra of low-density SiO₂ aerogel induced by Ca projectiles for different penetration depths

The Kα X-ray emission spectra of the low-density SiO₂ aerogel target bombarded by ⁴⁸Ca ions with initial energy of 11.4 MeV/u were measured with a high spectral and spatial resolution along 80% of the ion beam stopping path. The Si KαL⁰ diagram and KαLⁿ (up to n = 5) X-ray satellite lines corresponding to the radiative decays of atomic states with one hole in the K-shell and n-holes in the L-shell were measured. Energy shifts of the KαLⁿ satellites with respect to their diagram Kα lines were determined and compared with the results of multiconfiguration Dirac-Fock (MCDF) calculations. The experimental energy shifts are smaller than values obtained from free-ion MCDF theory assuming an empty M-shell. The influence of the valence M-shell configuration on the satellite X-ray spectra is discussed.