Chen [1] derived expressions for evaluating E using numerical approximations. The Chen method is useful for a broad range of energies ranging between 0.1 eV and 2.0 eV and pre-exponential factors between 10 ⁵ sec ^?1 and 10 ¹³ sec ^?1 and it does not make any use of iterative procedures. Furthermore, the method does not need any knowledge of the kinetics order which is directly found from the peak shape.

Its method is based on the shape of a TL peak, similarly to the Lushchik [2] and Halberin-Braner methods [3], For smplicity, the parameters involved in a well resolved peak are here reported in Fig.1,

Fig. 1: Parameters characterising a single peak.

where

• T _M , T ₁ , T ₂ : are respectively the peak temperature at the maximum and the temperatures on either side of the temperature at the maximum, corresponding to half intensity,

• ?=T _M ?T ₁: is the half-width at the low temperature side of the peak,

• ?=T ₂ ?T _M: is the half-width towards the fall-off of the glow peak,

• ?=T ? T ₁: is the total half-width,

• : is the symmetrical geometrical factor.

Total half-width peak method

• First order kinetics

Starting from the following first order equation, giving the TL intensity as a function of the temperature,

(1)

the equation for the maximum intensity, I _M, is given...