Simple experiment transparent for interpretation is presented in which afterglow of a discharge in helium with a small admixture of neon was studied. The intensities of the spectral lines of the Ne ^* atom at the stage of plasma decay were analyzed to find the conditions under which the dissociative recombination of heteronuclear ions HeNe ⁺ + e → He + Ne ^* played a predominant role in the formation of part of the afterglow spectrum. The absolute values of partial coefficients responsible for the formation of excited neon atoms in the 2p ⁵3p configuration were determined.