We have investigated the electron stimulated desorption of neutral metastable atoms from solid Argon condensed on a Pt (111) surface at 14 K. With time of flight techniques, we have observed the emission of photons and the ejection of two groups of metastable atoms, of very low kinetic energy (< 300 meV) and narrow angular distribution (15° width at half -maximum) along the surface normal. The photon signal is interpreted as resulting from the radiative de-excitation of the low-lying excimer states within the film and at the surface. Metastables originate mainly in the conversion of n=1 bulk free excitons to dissociative metastable states at the surface.