G. Possnert

A chronology of the Scythian antiquities of Eurasia based on new archaeological and C-14 data

The paper is compares the chronology of the monuments of the Scythian epoch located in the east and west of the Eurasian steppe zone on the basis of both archaeological and radiocarbon data. The lists of 14 C dates for the monuments located in different parts of Eurasia are presented according to the periods of their existence. Generally, the 14 C dates are confirmed the archaeological point of view and allow us to compare the chronological position of the European and Asian Scythian monuments on the united 14 C time scale.

The Quadrupole Moments of the First Excited 2+ States in 96 100 104Ru

The quadrupole moments of the first excited 2+ states in 96,100,104Ru have been measured using the reorientation precession technique. In 104Ru the sign of the Coulomb interference term P4 = M0+12+1 M0+12+2 M2+22+1 × M2+12+1 was determined and found to be P4 < 0. The quadrupole moment in 104Ru was determined to be -0.76 ± 0.19 eb. In 96Ru and 100Ru the measurements revealed quadrupole moments of -0.15 ± 0.27 eb and -0.40 ± 0.12 eb, respectively, independent of the sign of P4. The experimentally determined values are compared with theoretical calculations.

Experimental determination of electronic stopping for ions in silicon dioxide

The electronic energy loss for He4, Li7, Be9, C12, O16, F19, and Si28 ions in self-supporting silicon dioxide foils has been measured over a continuous range of energies. The measured He stopping powers are in good agreement with the SRIM-2003 (Stopping and Range of Ions in Matter) prediction. In the case of Li and C ions, the measured stopping powers exhibit some deviation from the SRIM-2003 predictions only around the Bragg peak; however, for Be, O, F, and Si ions, the measure stopping powers exhibit up to 10% deviation from the SRIM-2003 predictions over the entire energy range. The results indicate that the modified Bohr formula is suitable for scaling the stopping number for C and heavier ions in the classical interaction regime.

Sample requirements and design of an inter-laboratory trial for radiocarbon laboratories

Abstract An on-going inter-comparison programme which is focused on assessing and establishing consensus protocols to be applied in the identification, selection and sub-sampling of materials for subsequent 14 C analysis is described. The outcome of the programme will provide a detailed quantification of the uncertainties associated with 14 C measurements including the issues of accuracy and precision. Such projects have become recognised as a fundamental aspect of continuing laboratory quality assurance schemes, providing a mechanism for the harmonisation of measurements and for demonstrating the traceability of results. The design of this study and its rationale are described. In summary, a suite of core samples has been defined which will be made available to both AMS and radiometric laboratories. These core materials are representative of routinely dated material and their ages span the full range of the applied 14 C time-scale. Two of the samples are of wood from the German and Irish dendrochronologies, thus providing a direct connection to the master dendrochronological calibration curve. Further samples link this new inter-comparison to past studies. Sample size and precision have been identified as being of paramount importance in defining dating confidence, and so several core samples have been identified for more in-depth study of these practical issues. In addition to the core samples, optional samples have been identified and prepared specifically for either AMS and/or radiometric laboratories. For AMS laboratories, these include bone, textile, leather and parchment samples. Participation in the study requires a commitment to a minimum of 10 core analyses, with results to be returned within a year.

The 10Be marine record of the last 3.5 Ma

We present in this study a Be-10 profile from a deep-sea sediment section extending to 3.5 Ma. The Be-10 concentration ranges at 2-14 x 10(8) atoms/g and shows a clear decay trend. The flux of Be-1 ...

Transient magnetic fieldg-factor measurements of 2 1 + in64, 66, 68, 70Zn

The implantation perturbed angular correlation technique (IMPAC) has been used to determine the magnetic dipole moments of the first excited 2+ states in the stable even-even Zn-isotopes. Transient magnetic field measurements for56Fe in ferromagnetic Gd at 77 K have been performed for recoil velocities up tov/v0∼8. The result confirms the earlier reported linear velocity dependence. Theg-factors are deduced to be 0.46±0.10, 0.47±0.11, 0.46±0.14 and 0.30±0.07 for64, 66, 68Zn and70Zn respectively. The results are compared with theoretical predictions.

Temperature dependence of the hyperfine fields for fluorine in ferromagnetic iron, nickel and gadolinium

The temperature dependence of the magnetic hyperfine fields at the sites of F nuclei implanted into ferromagnetic Fe, Ni and Gd has been studied in the temperature range from 77 K to 670 K. A pulsed proton beam was used to observe the time-differential precession of the 5/2+ state in19F. Deviations from the bulk magnetization were found for Fe and Ni. The damping of the two observed fields in Ni was interpreted in terms of a field distribution caused by an induced radiation damage. The occupation sites for F and possible mechanisms of the anomalous temperature dependence are discussed.

127I and 129I Species and Transformation in the Baltic Proper, Kattegat, and Skagerrak Basins

Occurrence of anthropogenic (129)I in seawater has provided invaluable information about water circulation and exchange rates, but results on (129)I species (iodide and iodate) are limited and only available for surface water. We here present the first extensive results on (129)I and (127)I species in samples of seawater depth profiles, which were collected in August 2006 and April 2007 in the Skagerrak, Kattegat, and Baltic Proper. The results expose ≤10% annual reduction of iodate as (129)I is transported from the English Channel along the Dutch coast and German Bight into the Skagerrak and Kattegat. The results also suggest strong variability between surface and bottom seawater with respect to the predominant iodine species. Distribution of iodide and iodate of both (127)I and (129)I in the Kattegat mainly reflects water mixing process rather than speciation transformation. In water of the Baltic Proper, high (127)I(-)/(127)IO(3)(-) and (129)I(-)/(129)IO(3)(-) values suggest effective reduction of iodate with a maximum rate of 8 × 10(-7) ((127)IO(3)(-)) and 6 × 10(-14) ((129)IO(3)(-)) (g/m(3).day). The reduction process of iodate seems to be related to decomposition of organic matter and photochemically induced reactions.

Deep deuterium retention and Be/W mixing at tungsten coated surfaces in the JET divertor

Surface samples from a full poloidal set of divertor tiles exposed in JET through operations 2010-2012 with ITER-like wall have been investigated using SEM, SIMS, ICP-AES analysis and micro beam nu ...

Overview of nitrogen-15 application as a tracer gas for material migration and retention studies in tokamaks

Experimental and analytical procedures related to the application of nitrogen-15 isotope for material migration studies have been developed and used for tracer experiments in the TEXTOR and ASDEX-Upgrade tokamaks in order to assess the retention of nitrogen in plasma-facing components made of graphite and tungsten. The surface study was performed by time-of-flight heavy ion elastic recoil detection analysis and by means of nuclear reaction analysis based on the N-15(p, gamma alpha)C-12 process. In both tokamaks nitrogen retention has exceeded 10% of the injected gas. In ASDEX-Upgrade the largest fraction of N-15 has been detected on protruding parts near the injection port, while around 4% has been found in the divertor. The ASDEX-Upgrade results have also been modeled. Helium trapping has been measured in deposits containing tungsten and nitrogen.