Production of color centers in natural topaz neutron irradiated in the nucleus of Peruvian reactor RP-10

The ionizing radiation's give the necessary energy so that the electrons, originally bound to the atoms of the glass, they can occupy energy levels that are inside the forbidden band, producing defects in the topaz glass, creating in this way, color centers. The bands of energy absorption in the visible range (300-800 nm.) they are produced by the color centers in the natural topaz, after being irradiated with neutrons, in the nucleus of the Peruvian reactor RP-10. These bands are studied by the spectroscopy in the visible range. We find that the bands of energy absorption are different in colorless topazes and irradiated topazes. Depending of the energy of used radiation the impurities of the glass are activated, generating in this way, radioisotopes of lingering half life, it was developed a device made of aluminum and cadmium to absorb neutrons that are the causing of the activation of impurities and to favor the step to neutrons that cause the formation of color centers. These results are analyzed for the optimization of the irradiation with neutrons in the change of color of the topaz glass. (author)