Hannover 2016 – wissenschaftliches Programm
MS 10.4: Poster
Donnerstag, 3. März 2016, 16:30–19:00, Empore Lichthof
AMS measurements of 10Be, 26Al and 41Ca at DREAMS — •Andreas Scharf1, Shavkat Akhmadaliev1, Maurice Arnold2, Pascal Bohleber3, Ingo Leya4, Silke Merchel1, Georg Rugel1, Thomas Smith4, René Ziegenrücker1, and Lars Zipf3 — 1HZDR, Dresden, Germany — 2CEREGE, Aix-en-Provence, France — 3Universität Heidelberg, Germany — 4University of Bern, Switzerland
DREAMS, the DREsden AMS-facility, is performing routine accelerator mass spectrometry for the isotopes 10Be, 26Al, 36Cl, 41Ca and 129I. Sample ratios of 10Be/9Be as low as 8 x 10−15 (background-corrected) have been measured and an exposure age of about 330 years of a boulder of 3000 t in Nepal could be determined . We could demonstrate that a by-product of ice core drilling, so-called drilling chips, are also suitable for 10Be analysis of ice cores, instead of using valuable ice core samples. A set of several in-house 26Al and 41Ca standards has been made traceable to primary standards by cross-calibration . Numerous 26Al and 41Ca concentrations of meteorites could be determined, but for marine sediments there is still a need for a low-level (10−13) 26Al standard. ICP-MS measurements have shown that the steel pins used to fix the CaF2 sample material in the cathodes have high K-concentrations of (44.6 ± 2.2) µg/g. By replacing the steel pins with copper pins the 41K background during 41Ca measurements could be lowered by a factor of three.
Ref.:  W. Schwanghart et al., Science (2015), DOI:10.1126/ science.aac9865.  G. Rugel et al., Nucl. Instr. Meth.B (2015), in review.