LASER-BEAM INDUCED REMOTE THERMOLUMINESCENCE (R-TL) IMAGE FOR FUTURE PLANETARY MATERIAL SURVEY

Thermoluminescence (TL) of calcite (CaCO3) irradiated by gamma-rays ha s been measured from a distance by heating with a CO2 infrared laser b eam. The diameter of a TL spot at the exposure site increased due to t hermal diffusion and became dark. The surrounding area showed TL in th e form of a broad ring. TL images obtained after the exposure were com pared with those simulated by numerically solving the equation of thre e-dimensional heat diffusion using the parameters of the TL peaks, i.e ., frequency factors v(0I) = v(0II) = 5 x 10(11) s(-1) and activation energies E-I = 1.28 and E-II = 1.58eV, the thermal conductivity and th e specific heat. The remote TL (R-TL) may be used in the future for pl anetary survey by heating or exciting a ground object from a rover or from a spacecraft.