[en] Photon induced L₃X-ray measurements for L_α/L_ℓ cross-sectionratios in elements, 66 ⩽ Z ⩽ 83, at tuned photon energies on synchrotron Beamline-16 atIndus-2, India have been used to study the effect of Coster-Kronig (CK) transitions andphoton energies on alignment of L₃ vacancies. Certainty and reliability of the measurementswere checked from comparison of measured L_α and L_ℓ fluorescencecross-sections at E₁ excitation with availabletheoretical/empirical/experimental values that required additional measurements forsource, geometry and efficiency factor S₀GεL_α/ℓ in the used set-up.Fall/rise trend of the ratios with energy for different Z’s was found to resemblethe off/on-set pattern of CK transitions as pointed out by Bambynek et al. and Campbell.Evaluated alignment parameter A₂ values are very much within thelimits, 0.05<A₂< 0.5, except for Lu, Ta and Pb atE₂ excitation and for W, Pt and Hg atE₁ excitation where values are<0.05. At E₃ excitation,the vacancies only in L₃ are aligned (A₂ ≦ 0.2) in all the cases. The patternof A′₂ (Coster-Kronig corrected A₂) variationwith energy for Dy, W, Pt, Hg and Bi resembles our previously reported theoreticalpatterns that lends mutual support for both current measurements and earlier theoreticalresults. Graphical abstract: .