No abstract available

No abstract available

[en] Electrodeposition is the major method for source preparation of actinides, Pu, Am, Th, U using stainless steel discs and spontaneous deposition for Polonium using discs of silver. Worldwide coins are manufactured of bronze, steel, copper plated steel, cupronickel, brass and alloys of Cu-Ni-Zn. The price of the coins which can be used have a value between 0.1 and 0.4 Euro considerably cheaper than electropolished stainless steel discs, 0.8 Euro. This investigation had the purpose to show the possibility to use coins from different countries for source preparation, the energy resolution and deposition efficiency. We obtained plating recoveries ranging from 50 to 100 % and the energy resolution varied between 21 and 75 keV for the different coins tested. (author)

[en] The development of radioanalytical methods for low level radionuclides in marine environmental samples is presented. In particular, emphasis is placed on the introduction of extraction chromatography (EC) as a tool for improving the quality of results as well as reducing the analysis time. However, the advantageous application of EC often depends on the effective use of suitable preconcentration techniques, such as co-precipitation, to reduce the amount of matrix components which accompany the analytes of interest. On-going investigations in this field relevant to the determination of environmental levels of actinides, ¹³⁷Cs and ⁹⁰Sr are discussed. (author)

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[en] A novel fabrication method for soft x-ray transmission grating and other optical elements is presented. The method uses focused-ion-beam technology to fabricate high-quality free standing grating bars on transmission electron microscopy grids. High quality transmission gratings are obtained with superb accuracy and versatility. Using these gratings and back-illuminated CCD camera, absolutely calibrated x-ray spectra can be acquired for soft x-ray source diagnostics in the 100−3000 eV spectral range. Double grating combinations of identical or different parameters are easily fabricated, allowing advanced one-shot application of transmission grating spectroscopy. These applications include spectroscopy with different spectral resolutions, bandwidths, dynamic ranges, and may serve for identification of high-order contribution, and spectral calibrations of various x-ray optical elements.

[en] Daily air monitoring of radionuclides in the Principality of Monaco (43°73′N, 7°43′E) after the Fukushima Daiichi nuclear power plant accident showed that only Iodine-131 (¹³¹I) and Caesium isotopes (¹³⁴Cs and ¹³⁷Cs) were detected. The peak of ¹³¹I varied and reached its maximum between March 29th and April 5th, meanwhile both peaks of ¹³⁴Cs and ¹³⁷Cs arrived later and attained a maximum between April 1st and 4th. Their maximum activity concentrations in air were 354, 30, and 37 μBq m⁻³ respectively. The ¹³⁴Cs to ¹³⁷Cs activity ratio was close to 1, which is different from that one observed after the Chernobyl accident (around 0.54). Up to 95% of caesium isotopes were washed out by wet scavenging during 27–28th of March, where the maximum deposition rates of ¹³⁴Cs and ¹³⁷Cs (13.7 and 19.1 mBq m⁻² day⁻¹, respectively) were observed. The significant input of ¹³⁴Cs and ¹³⁷Cs into the Mediterranean seawater column (30 m depth) was detected later, on the 24th of May. Radioisotopes of caesium and iodine were found far above the applied detection limits, but still with no concern for harmful radiation exposure and public health. The contamination gradually decreased in air and activity concentrations returned to background values after one or two months. - Highlights: ► Daily air concentrations of radionuclide in Monaco have been monitored. ► Radionuclides originating from the Fukushima accident were detected. ► Iodine-131 and ¹³⁴Cs and ¹³⁷Cs were detected in low levels, 354, 30, and 37 μBq m⁻³. ► The peak of ¹³¹I varied and reached its maximum between March 29th and April 5th.► ¹³⁴Cs and ¹³⁷Cs were later than ¹³¹I, and attained a maximum between April 1st and 4th.

No abstract available

[en] Extremely radiation hard sensors are needed in particle physics experiments to instrument the region near the beam pipe. Examples are beam halo and beam loss monitors at the Large Hadron Collider, FLASH or XFEL. Currently artificial diamond sensors are widely used. In this paper single crystal sapphire sensors are considered as a promising alternative. Industrially grown sapphire wafers are available in large sizes, are of low cost and, like diamond sensors, can be operated without cooling. Here we present results of an irradiation study done with sapphire sensors in a high intensity low energy electron beam. Then, a multichannel direction-sensitive sapphire detector stack is described. It comprises 8 sapphire plates of 1 cm"2 size and 525 μ m thickness, metallized on both sides, and apposed to form a stack. Each second metal layer is supplied with a bias voltage, and the layers in between are connected to charge-sensitive preamplifiers. The performance of the detector was studied in a 5 GeV electron beam. The charge collection efficiency measured as a function of the bias voltage rises with the voltage, reaching about 10%  at 095 V. The signal size obtained from electrons crossing the stack at this voltage is about 02200 e, where e is the unit charge. The signal size is measured as a function of the hit position, showing variations of up to 20% in the direction perpendicular to the beam and to the electric field. The measurement of the signal size as a function of the coordinate parallel to the electric field confirms the prediction that mainly electrons contribute to the signal. Also evidence for the presence of a polarisation field was observed

[en] Extremely radiation hard sensors are needed in particle physics experiments to instrument the region near the beam pipe. Examples are beam halo and beam loss monitoring systems at the Large Hadron Collider, FLASH or XFEL. Artificial diamond sensors are currently widely used as sensors in these systems. In this paper single crystal sapphire sensors are considered as a promising alternative. Industrially grown sapphire wafers are available in large sizes, are of low cost and, like diamond sensors, can be operated without cooling. Here we present results of an irradiation study done with sapphire sensors in a high intensity low energy electron beam. Then, a multichannel direction-sensitive sapphire detector stack is described. It comprises 8 sapphire plates of 1 cm² size and 525 μm thickness, metallized on both sides, and apposed to form a stack. Each second metal layer is supplied with a bias voltage, and the layers in between are connected to charge-sensitive preamplifiers. The performance of the detector was studied in a 5 GeV electron beam. The charge collection efficiency of the sensors was measured as a function of the bias voltage. It rises with the voltage, reaching about 10 % at 950 V. The signal size obtained from an electron crossing the stack at this voltage is about 22000 e, where e is the unit charge. Using the EUDET beam telescope, beam electrons trajectories where reconstructed, allowing to determine the position of the hits on the detector. The signal size is measured as a function of the hit position, showing variations of up to 20 % in the direction perpendicular to the beam and to the electric field. The measurement of the signal size as a function of the coordinate parallel to the electric field confirms the prediction that mainly electrons contribute to the signal. Also evidence for the presence of a polarization field was observed.