Chronological study archaeological sites from Caninde do Sao Francisco, Sergipe state, Brazil, by thermo thermoluminescence technique

The ceramic vestiges rescued in the archaeological excavations have been considered important sources of chronological information because they constitute direct fossil of certain cultural periods. The Thermoluminescence Method for dating of inorganic materials has made the determination of ancient ceramics ages possible with adequate precision and accuracy. The intensity of the thermoluminescence emission is proportional to the energy deposited in the crystals, present in the pottery, by means of natural radioisotope material irradiation (U, Th, K and Rb) and cosmic rays. With the objective of determining the chronological profile of archaeological sites from 'Xingo', situated in the Caninde do Sao Francisco city, Sergipe State, Brazilian Northeast, the ages of 4 pottery samples from Justino, Sao Jose, Saco da Onca and Curituba sites were determined in this work. The ceramic collection has great expression because many ceramics are associated to mortuary rites. The acquisition of the site chronology studied in this work is a contribution to studies of ancient communities that lived in the region. The additive dose method was used to determine of the paleodose in the samples, and the TL response of 320 deg C peak as function of the added dose was linear. The annual dose rate was determined by means of the instrumental neutron activation analysis, using the U, Th, K and RB concentration from soil and own sample, which yielded an average annual dose rate of 2.89 ± 0.33 mGy.yr-1. Using of the paleodose and annual dose rate, the ages were determined which remained between 457 - 3716 BP, value which matches with the results obtained by carbon - 14 method in the sample from burned charcoal in Justino site. (author)