A NEW HIGH-SENSITIVITY SPECTROMETER FOR 3-D THERMOLUMINESCENCE ANALYSIS

The features of a new spectrometer for measuring wavelength-resolved T L emission are described: the system is based on wide angle mirror opt ics and the dispersive element is a hat-held holographic grating, with numerical aperture f/2. The detector is a two stage MCP (micro-channe l plate) followed by a 512 photodiode array. The whale system, cooled by a Peltier control unit, reaches a signal-to-noise ratio comparable with a photomultiplier one. The high sensitivity of the apparatus allo ws the measurement in dosimetric materials, TL due to irradiations low er than 100 mu Gy. In quartz extracted from ancient ceramics the TL pr oduced by natural irradiation has been detected.