A flowing afterglow chemiluminescence apparatus has been used to analyze visible fluorescence in the Ar*(3P 20)+Ca(1S0) reaction. The rate constants for production of Ca+(2P 3/20) and Ca+(2P 1/20) were measured to be 1.6×10−10 and 3.2×10−11 cm3 molecule−1 sec−1, respectively. These results demonstrate a transfer of the total electronic angular momentum polarization in Ar* to the excited ion levels. The molecular band spectrum of the associative ionization product CaAr+(A 2Π) was observed. Molecular fluorescence constituted 14% of the total fluorescence from all ion products. This spectrum was analyzed with a model (exp-Z4) potential, yielding, for the ground state X 2Σ+, Re = 2.8 Å, ωe″ = 87 cm−1, and De″ = 1000 cm−1, and, for the A 2Π state, Re = 2.6 Å, ωe′ = 200 cm−1, and De′ = 4900 cm−1. The nascent internal state distribution in CaAr+ is found to consist of a fairly narrow range of high vibrational levels.