Prompt Gamma Activation Research Articles

Production technology and knowledge transfer of calcite‐tempered grey ware bowls from 2nd‐ to 5th‐century ceNoricum (Austria)

AbstractAspects of 2nd‐ to 5th‐century ce Roman production technology and knowledge transfer in southern Austria (known as Noricum) were examined. With no evidence for workshops identified in the study area, 44 grey ware bowls from two sites at Aguntum and Lavant were studied macroscopically, and combined with optical microscopy, X‐ray powder diffraction, prompt gamma activation, neutron activation and scanning electron microscopy, in order to understand whether one (large) workshop supplied these bowls, or whether the bowls were produced by several (small) workshops nearby. Combined with information from the geological background, the results were used to tentatively indicate the production location.The results indicate that the grey ware bowls from Aguntum and Lavant were produced by local workshops nearby. The bowls were manufactured with similar clay sources, tempered with crushed calcite‐marble rocks from the Tauern Window, their surface smoothed and burnished, and fired between 800 and 850°C in a reducing atmosphere of an open fire. This is taken to suggest that Roman potters, who were located at Aguntum and Lavant, shared strategies of raw materials selection, paste preparation, finishing and firing, and transferred technological knowledge through time.

Evaluation of Major and Trace Elements Present in Extracted Humic Acid from Bog Peat

The human consumption of humic acid is increasingly relevant therefore the knowledge of exact composition is essential. To make a step in that direction we present gap filling results obtained from three different element analytical investigations of humic acid extracted from fen peat examined in the Carpathian Basin. Prompt-gamma activation (PGAA), neutron activation analytical method (NAA) and X-ray fluorescence (XRF) analysis was carried out. After presenting and explaining the essence of used analytical methods we show some collected spectra and a table where all the concentration of the iden- tified elements are presented with the corresponding measurement errors. All together 42 elements were identified. PACS.78.70.En, 78.70. Nx,78. 90.+t X-ray emission spectra and fluorescence, Neutroninelastic scattering, Other topics in optical properties, condensed matter aspect.

Transformations of Metal Supply during the Bronze Age in the Carpathian Basin

This paper presents recent research questions which have been raised and methods which have been used in the study of Bronze Age metallurgy in connection with available natural resources (ores) in and around the Carpathian Basin. This topic fits in the most current trends in the research on European prehistoric archaeology. Given the lack of written sources, copper and bronze artifacts discovered in settlement and cemetery excavations and prehistoric mining sites provide the primary sources on which the studies in question are based. The aim of compositional and isotope analysis of copper and tin ores, metal tools, ornaments, and weapons is to determine the provenience of the raw materials and further an understanding of the chaine operatiore of prehistoric metal production. The Momentum Mobility Research Group of the Institute of Archaeology, Research Centre for the Humanities studies these metal artifacts using archaeological and scientific methods. It has focused on the first thousand years of the Bronze Age (2500–1500 BC). Multidisciplinary research include non-destructive XRF, PGAA (promptgamma activation), TOF-ND (time-of-flight neutron diffraction) analyses and neutron radiography, as well as destructive methods, e.g. metal sampling for compositional and lead isotope testing, alongside archaeological analysis. Microstructure studies are also efficient methods for determining the raw material and production techniques. The results suggest the use of regional ore sources and interregional connections, as well as several transformations in the exchange network of the prehistoric communities living in the Carpathian Basin.

Determination of chlorine concentrations in whole rock: Comparison between prompt-gamma activation and isotope-dilution AMS analysis

Accurate determination of chlorine concentrations in terrestrial rocks is of importance for the interpretation of terrestrial in-situ cosmogenic 36Cl. Neutron capture by 35Cl, together with production from Ca and K, is one of the three major production pathways of 36Cl in rocks. Here, we present an inter-comparison of chlorine determinations by two procedures. The first approach is an independent Cl determination by prompt-gamma (neutron) activation analysis (PGAA). The second method is isotope-dilution based on isotopically enriched stable chlorine carrier added during chemical sample preparation for accelerator mass spectrometry (ID-AMS). Twenty-six (26) whole rock samples have been processed for PGAA and ID-AMS analysis. This study constitutes the first published inter-comparison for concentrations below 100 μgCl/g. Our results show no significant difference in Cl concentrations between methods. This agreement indicates good retention of chloride during the procedure we employ for whole rock sample dissolution. No significant loss of stable chlorine from either the spike or the sample occurs before isotopic equilibrium is reached, prior to AgCl precipitation. Uncertainties, which are <5% for both methods, affect the uncertainty of the total 36Cl production rate less than 2% for our samples. The Cl concentration measured by PGAA can be used to calculate the amount of isotopically enriched spike for AMS-ID sample preparation with the aim to optimize 36Cl analysis. Furthermore, PGAA offers an advance for the interpretation of 36Cl measurements. It allows measurement of concentrations of major, minor and trace elements including the elements for 36Cl production (Cl, K, Ca, Ti, and Fe), as well as of neutron absorbers and neutron moderators (H, B, Sm and Gd). These measurements are performed simultaneously and with a precision necessary for calculating the relative contributions to 36Cl production from the different mechanisms.

Non-destructive analysis of a bulky sample from a natural fossil reactor

Two non-destructive and position sensitive methods were used to analyzea sample coming from the reactor site of Okelobondo near Oklo (Gabon). Atthe European Synchrotron Radiation Facility (ESRF), uranium and lead werevisualized in this piece by element sensitive tomography. The same samplewas then studied with the new prompt gamma activation (PGA) facility at theSwiss spallation neutron source SINQ (PSI Villigen). A neutron focusing capillarylens permits to upgrade PGA to a position sensitive method. In the Oklo samplethe concentration of uranium but also of 7 other elements were spatially analyzed.