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Thermogravimetric (TG/DTG), thermoluminescence (TL), and X-ray powder diffraction (XRD) techniques were applied to characterize samples collected from the archaeological site of Polutepe in Azerbaijan, dating to the Neolithic period, and gave new information on the firing technology. The thermogravimetric analysis of ceramic shards from Polutepe revealed that the firing temperature of the samples was in the range of 700°C, based on the presence of calcite in the sample. XRD analysis confirmed the presence of quartz, feldspar, and clay minerals in the ceramic samples. According to XTD analysis the mineral composition of the ceramic sample from Polutepe site was as follows: Quartz-33.8 mass%, Feldspar (albite)-21.7 mass%, Muscovite- 33.6 mass%, and Calcite- 10.9 mass%. TL glow-curve intensity at 325°C was measured to estimate the historical dose of the sample, which was found to be 22.19±1.36 Gy. The concentration of U, Th, and K were 2.24±0.20 ppm , 8.31±0.80 ppm, 2.39±0.23% respectively. Dose rate and age calculation were conducted using the DRAC, version 1.2 and output results are as follows: Environmental dose rate: 3.46±0.19 mGy/a; Age of the sample: 4.400±530 BC years which are in line with the stratigraphically estimated age of this area and with the radiocarbon age (4270±160 BC) reported in our previous work. The results obtained from this multidisciplinary approach provide insights into the firing technology and age of the ceramic samples.

Isothermal decay of the TL glow curve has been studied at ambient temperature. Heating of feldspar at 600ºC leads to increased sensitivity of the samples upon irradiation for the whole range of glow curve. In general, we observe a sensitivity increase of about five times. Fading of the glow curve is observed at the low-temperature part of the glow curve while it has been kept in the dark at the ambient, constant temperature. After a certain period, approximately in 40 to 50 days, the low-temperature region of the glow curve fades down while the high-temperature part remains unchanged. Peaks at the low-temperature region of the TL glow curve were isolated by the curve subtraction method. Activation energy and frequency factor parameters of the isolated peaks were calculated, taking first and second-order kinetics into account. The values of the calculated activation energy vary between 0.7 to 1.1 eV, and frequency factor values of the isolated peaks change within the order of 109 to 1013s-1. The µ values clearly indicate that all isolated peaks are more likely to be second-order kinetics.