A method of estimating the electron affinity value of an insulator has been developed. The measurement was carried out from the simultaneous detection of thermoluminescence and thermostimulated exoelectronic emission (TSEE) curves presented by the material. This is possible when the TSEE phenomenon is governed by the thermoionic model and when the electron concentration of the considered trap becomes weaker than that of thermally disconnected traps. The application to an -alumina single crystal shows that the electron affinity can be evaluated as from the thermostimulated peak at 275 K and at from the thermostimulated peak at 440 K. The validity of the model and the signification of the results are discussed.

A systematic study of TSEE curves obtained after UV or X irradiations at 77 K from alumina samples of various origin is reported. These curves are systematically compared with TL glow curves recorded in similar conditions. Nine positions for thermostimulated peaks are detected in the 77 to 600 K range. These peaks appear with various occurrence frequencies. Except for the first peak (100 K, peak A) which does not exist in the majority of the TSEE curves recorded, the main TSEE peaks coincide fairly well with the correspondent TL peaks. A mechanism is proposed to interpret the behaviour of peak A.

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