Vacuum-UV emission spectra were obtained in a discharge flow system for reactions of bromine-, chlorine- and iodine containing reagents with metastable argon atoms (Ar(3P2~0). Halogen atomic lines were observed for many of these spectra. Noble gas halide spectra were identified for the reactions of the bromine- and chlorine- containing reagents (ArBr- and ArCl- spectra). HC1 and DC1 spectra were observed for the reactions of these reagents. The pressure- and temperature-dependence behaviour of some of the argon halide spectra as well as their structure was studied, and the spectra were analysed by simulation calculations. Detailed studies of the effect of the various parameters on the calculated spectra were carried out for the simulation of the ArBr spectra. This showed that important information on the various parameters could be derived from the simulation calculations. Spectral contributions due to three different bound-free transitions (B-X, C-A(3/2)) and B-A(1/2)) and the spectral ranges of these were identified for some ArBr spectra. Only the very lowest vibrational levels in the excited states were found to emit due to an efficient predissociation of high vibrational levels. The occurrence of a collision induced crossing between the emitting states (B and C) and a vibrational relaxation in these states was observed. Estimates were made of relative rates of collisional deactivation processes and population distributions in the emitting states (B and C) for some of the spectra. Approximate potential curves (X, A(3/2), B and C) were obtained and the transition moments for the transitions B-X' and C-A(3/2) were found to vary rapidly with internuclear distance. Analyses of some ArCl MC spectra made it possible to estimate the population distribution in the ArCl B-state and the occurrence of a rapid vibrational relaxation in the B-state was observed. Approximate potential curves (X, B) were also obtained.