TL dating of pottery fragments from four archaeological sites in Taquari Valley, Brazil

Sixty-three pottery fragments from four archaeological sites, numbered RST110, RST101, RST114 and RST114, in the Taquari Valley, vicinity of the city of Lajeado, Rio Grande do Sul state, southern Brazil, have been dated by the thermoluminescence method. Some of them from RST110 and RST101 are as old as 1400-1200 years, whereas those from RST114 and RST107 are younger than 800 years. This result indicates that RST101 and RST110 were peopled earlier than RST114 and RST107. The recent dates found are 302, 295 and 146 years and they are possible, since the first German immigrants who arrived in this region encountered Tupi-Guarani Indians still living there. One interesting result refers to the glow curves of quartz grains RST110, RST101 and RST114 that differ from the glow curves of RST107 quartz grains.

First measurement of beta decay half-lives in neutron-rich Tl and Bi isotopes

Neutron-rich isotopes around lead, beyond N = 126, have been studied exploiting the fragmentation of an uranium primary beam at the FRS-RISING setup at GSI. For the first time beta-decay half-lives of Bi-219 and Tl-211,Tl-212,Tl-213 isotopes have been derived. The half-lives have been extracted using a numerical simulation developed for experiments in high-background conditions. Comparison with state of the art models used in r-process calculations is given, showing a systematic underestimation of the experimental values, at variance from close-lying nuclei. (c) 2012 Elsevier B.V. All rights reserved.

TL, OSL and C-14 dating results of the sediments and bricks from mummified nuns' grave

This paper presents the results of TL and OSL dating of soil and fragments of bricks from a grave, which was occupied by two mummified nuns, found at "Luz" Monastery, located in the state of São Paulo, Brazil. The TL and OSL ages were compared to C-14 dating ones obtained from bone collagens of the mummies. The majority of the ages is related to the eighteenth century. The gamma-ray spectroscopy was used to evaluate natural radioisotope concentrations in the samples, and by using these concentrations the annual dose rates, from 3.0 to 5.3 Gy/kyr, were obtained. Neutron activation analysis was performed and the radioisotope contents results are in agreement with those obtained by gamma-ray spectroscopy. The contents of U, Th and Ce elements were higher than those found in usual sediments.