The present invention provides a method and system for measuring the spatial distribution of fluorescence from the excited radiochromic luminescent material; and for signal processing of the spatial distribution of fluorescence to thereby detect tracks of one or more heavy charged particles with which the luminescent material has been irradiated. The present invention also provides a method and system for measuring the spatial distribution of fluorescence from an excited radiochromic luminescent material that has been irradiated with a hot particle of a radioactive material. The present invention provides a method for detecting thermal and fast neutrons as well as a method for determining parameters of heavy charge particles. In several embodiments of the present invention, the luminescent material comprises Al.sub.2O.sub.3 doped with magnesium and carbon.