Perturbation on atomic alignment of Ag L₃-subshell by multiple ionization for heavy ions impact

Alignment of silver ion after electron in L3-subshell ionized by 1H+, 4He2+, 40Ar12+ and 129Xe30+ ions impact respectively are reported. Low incident energy range is investigated to explore collision-induced alignment in case of strong Coulomb deflection effect. Characteristic L X-ray spectra are measured in emission angle range of 115 degrees -155 degrees. For L & alpha; and L & beta; 2 lines, anisotropy parameter & beta; is determined respectively and then converted to degree of alignment .a60 by taking anisotropy coefficient & alpha; and Coster-Kronig (CK) correction coefficient & kappa; into account. The measured atomic alignment is compared to theoretical prediction basing on semiclassical model and satisfactory agreement is observed only for light ions impact. While the dealignment coefficient is determined to be 0.98, 0.71 and 0.30 for 4He2+, 40Ar12+ and 129Xe30+ ions impact at (vp/vL3 2 =0.011, respectively. This work demonstrates the strong dealignment due to multiple ionization for heavy ions impact even in ultra low incident energy regime.& COPY; 2023 Elsevier B.V. All rights reserved.