[en] To comply with regulations and to ensure state of the art treatment of historical conditioned radioactive waste in Austria, as well as to guarantee safe interim storage until 2045, historic conditioned radioactive waste is being reconditioned in an ongoing project. Drums with waste forms of all three main conditioning types (drums with super-compacted pellets, homogeneously cemented and in-homogeneously cemented drums) found in Austria have already been reconditioned. Experiences from the reconditioning of all three types of drums and information regarding the status of the project is being shared. Steps of special importance proved to be the pre-sorting of the different waste types derived from existing documentation, the use of a specialized modular machinery for the dismantling of the drums layer by layer to limit cross-contamination, and the characterization of the waste performed in tandem and afterwards. As a last step, documentation of the original drum is consolidated with the information from the reconditioning processes and from radiological and chemical assays. (author)

[en] After 38-year safe operation the 10 MW ASTRA Research Reactor Seibersdorf was switched off in the year 1999. Shortly after the dismantling began and were finalized in the year 2006. The research reactor was housed in a cylindrical building (reactor building, reactor hall) with 26 m diameter and 22.5 m height, which were conceived as reactor containment and which should be free-measured for unlimited applications. Because no neutron activation of the building was expected, the free measurements were confined only of contamination measurements of the building (walls, floors, covers and crane superstructures), which was possibly surface-contaminated by handling for many years with radioactive substances. After free-measurements an application for release of the building was filed at the authorities. After arrival of the release answer the reactor containment was cleared and released from the radiation protection law. The released empty reactor building should be reorganized into a transfer storage of non radioactive material. (orig.)

[en] Full text: Samples required to environmental questions are often complex (e.g., contaminated soils, lake and dump sediments). They consist of mixtures of mineral phases (often with small particle sizes), microbes, and living tissues. Elemental distribution, spatially resolved chemical speciation and mineral phase identification are helpful to uncover relationships between mineral phases, main and trace elements and finally to comprehensively understand anthropogenic affected systems. Such problems can be addressed by a combination of microfocused synchrotron x-ray techniques as they have been setup with the Synchrotron Radiation Laboratory for Environmental Studies (SUL) at the synchrotron radiation facility ANKA. The lab consists of a microfocus x-ray beamline (SUL-X) that enable elemental mapping using x-ray fluorescence analysis (XRF), chemical speciation with x-ray absorption spectroscopy (XAS) and mineral phase determination by x-ray diffraction (XRD), successively at the same sample position. Moreover, the laboratory is supplemented with an infrared microscope (SUL-IR) at an IR beamline. The experimental station of SUL-X is equipped with various detectors for different x-ray techniques: Ionization chambers, 7 element solid state detector for XAS and XRF-spectroscopy; a CCD detector for x-ray diffraction and a light microscope in transmission and reflection for adjusting sample positions. Research fields during the first commissioning period comprised speciation of As from mining activities, incorporation of Pb in the human body and mineral precipitations that may have an influence on the carbon exchange between ocean water and atmosphere. SUL-X is now open from 4 to 16 keV for users. To meet the demand of speciation of low Z elements like Al, Si, P, S for environmental questions, it is planned to offer XAS at energies from about 20 keV down to the Al K edge (1.5 keV). Because of the low energy option the experimental station can be operated under vacuum. (author)

[en] The cross section of the Li-7(n,gamma)Li-8 reaction was studied in the neutron energy range 25-420 keV to investigate the role of this reaction for the production of nuclei with A of 12 or greater in primordial nucleosynthesis. The experimental results are compared with theoretical model calculations. The reaction rate obtained is significantly smaller than previously suggested. This results in a reduced production of heavy elements and in reduced feeding of a proposed primordial r-process. 33 refs

[en] The paper presents work performed in the last phase of the decommissioning of the ASTRA research reactor at the Austrian Research Centers Seibersdorf. Dismantling the pump room installations and the ventilation system, as well as the clearance of the buildings is described. Some conclusions and summary data regarding the time table, material management, and the cost of the entire project are also presented. (author)

[en] An efficient referencing and sample positioning system is a basic tool for a micro focus beamline at a synchrotron. The seven years ago introduced command line based system was upgraded at SUL-X beamline at ANKA [1]. A new combination of current server client techniques offers direct control and facilitates unexperienced users the handling of this frequently used tool. (paper)

[en] Different methods have been proposed to calculate the vertical position of the photon beam centroid from the four blade currents of staggered pair X-ray beam position monitors (XBPMs) at bending magnet beamlines since they emerged about 15 years ago. The original difference-over-sum method introduced by Peatman and Holldack is still widely used, even though it has been proven to be rather inaccurate at large beam displacements. By systematically generating bumps in the electron orbit of the ANKA storage ring and comparing synchronized data from electron BPMs and XBPM blade currents, we have been able to show that the log-ratio method by S. F. Lin, B.G. Sun et al. is superior (meaning the characteristic being closer to linear) to the ratio method, which in turn is superior to the difference over sum method. These findings are supported by simulations of the XBPM response to changes of the beam centroid. The heuristic basis for each of the methods is investigated. The implications on using XBPM readings for orbit correction are discussed

[en] Initially, ANKA has been equipped with 8 beamlines, which is by far less than the overall potential of the facility. As a result, several proposals for additional installations have been proposed. Among these, the most demanding are focusing on insertion devices like a superconducting miniundulator. Such an undulator is planned for producing X-rays for a dedicated Synchrotron Environmental Laboratory at ANKA. Furthermore, this concept based on superconductivity provides an enormous potential for other medium-energy synchrotron light sources. Other examples for new ideas include an insertion device for low-cost-high-throughput micro-fabrication. (orig.)

[en] The dissolution parameters of calcium carbonates play a key role in agriculture as they regulate the plant nutrients uptake and buffer the pH-value of the soil. The combination of μXRF, μXAS and μXRD mapping in the hard X-ray regime for the examination of both short- and long range order in natural limestones revealed that their dissolution properties depend both on the crystallinity of the mineral phases and their composition. The results particularly show that in many cases the presence of magnesium inhibits dissolution of the phases. (paper)

[en] The cross section of the ³³S(n,α)³⁰Si reaction was measured in a neutron energy spectrum yielding the stellar rate for a thermal energy of kT=25 keV. For the ³⁶Cl(n,p)³⁶S reaction, the experiment was performed in the neutron energy range from 10 to 260 keV. Our new result for ³³S resolves the problem of a large discrepancy between two previous experiments. In case of ³⁶Cl it could be shown that the (n,α) channel is negligibly small compared to the (n,p) reaction at s-process conditions. The present results are used for a detailed discussion of a possble s-process origin of the rare neutron-rich isotope ³⁶S