Study of gaussian fitting methods applied to thermoluminescent emission spectrum of CaSO4:Dy

In the present work, two methods used to represent the peaks of the thermoluminescence (TL) glow curve of CaSO4:Dy, from a gaussian approximation, are evaluated. Several glow curves with single and double peaks and known parameters were computationally simulated. Two procedures were applied to the data: gaussian curve fitting to the simulated data by the least squares method; and peak approximation by a gaussian function, from a method developed in the Applied Physics Division of IEAv/CTA. The obtained results (gaussian curve areas) in comparison with the original area of the TL glow curve generated for the single peak case show a tendency of underestimate the real area from 0.8 to 7.0%, depending on the fitting method applied. For the double peak case, it was observed an emphasized tendency of overestimate the original curve area from 3.7 to 6.2%, depending on the fitting method used. The obtained result is discussed in relation to the utilization of the method as a dosimetry routine, its implications and limitations. (author)