TY - JOUR A1 - Merchel, S. A1 - Bremser, Wolfram A1 - Akhmadaliev, S. A1 - Arnold, M. A1 - Aumaître, G. A1 - Bourlès, D.L. A1 - Braucher, R. A1 - Caffee, M. A1 - Christl, M. A1 - Fifield, L.K. A1 - Finkel, R.C. A1 - Freeman, S.P.H.T. A1 - Ruiz-Gómez, A. A1 - Kubik, P.W. A1 - Martschini, M. A1 - Rood, D.H. A1 - Tims, S.G. A1 - Wallner, A. A1 - Wilcken, K. M. A1 - Xu, S. T1 - Quality assurance in accelerator mass spectrometry: results from an international round-robin exercise for 10Be N2 - The first international round-robin exercise for the measurement of the long-lived radionuclide 10Be has been conducted. Ten participating accelerator mass spectrometry (AMS) facilities have each measured three samples at the 10-12 to 10-14 10Be/9Be level. All results have been made traceable to the NIST SRM 4325 standard to avoid additional discrepancies that arise when different facilities use different calibration materials. Hence, the data concentrates on pure measurement distinctions. Multivariate statistical investigations have been performed to reveal a bias between facilities, i.e. two distinguished groups could be identified. Maximum discrepancies between two single facilities are in the range of 6–31% depending on the absolute 10Be/9Be value. These findings should be considered when comparing 10Be data produced at one AMS facility with that produced at another facility, which is e.g. often the case for in situ 10Be dating studies. Round-robin exercises are a very helpful tool as part of an overall quality assurance scheme to improve the accuracy, and not only the precision, of AMS data. KW - Accelerator mass spectrometry KW - Terrestrial cosmogenic nuclides (TCN) KW - Cosmogenic nuclides (TCN) KW - Cosmogenic nuclide exposure dating KW - Calibration PY - 2012 DO - https://doi.org/10.1016/j.nimb.2012.07.038 SN - 0168-583X SN - 1872-9584 VL - 289 SP - 68 EP - 73 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-26772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Merchel, S. A1 - Bremser, Wolfram A1 - Alfimov, V. A1 - Arnold, M. A1 - Aumaître, G. A1 - Benedetti, L. A1 - Bourlès, D.L. A1 - Caffee, M. A1 - Fifield, L.K. A1 - Finkel, R.C. A1 - Freeman, S.P.H.T. A1 - Martschini, M. A1 - Matsushi, Y. A1 - Rood, D.H. A1 - Sasa, K. A1 - Steier, P. A1 - Takahashi, T. A1 - Tamari, M. A1 - Tims, S.G. A1 - Tosaki, Y. A1 - Wilken, K. M. A1 - Xu, S. T1 - Ultra-trace analysis of 36Cl by accelerator mass spectrometry: an interlaboratory study N2 - A first international 36Cl interlaboratory comparison has been initiated. Evaluation of the final results of the eight participating accelerator mass spectrometry (AMS) laboratories on three synthetic AgCl samples with 36Cl/Cl ratios at the 10-11, 10-12, and 10-13 level shows no difference in the sense of simple statistical significance. However, more detailed statistical analyses demonstrate certain interlaboratory bias and underestimation of uncertainties by some laboratories. Following subsequent remeasurement and reanalysis of the data from some AMS facilities, the round-robin data indicate that 36Cl/Cl data from two individual AMS laboratories can differ by up to 17%. Thus, the demand for further work on harmonising the 36Cl-system on a worldwide scale and enlarging the improvement of measurements is obvious. KW - Accelerator mass spectrometry KW - Long-lived radionuclides KW - Cosmogenic nuclides KW - Exposure dating PY - 2011 DO - https://doi.org/10.1007/s00216-011-4979-2 SN - 1618-2642 SN - 1618-2650 VL - 400 IS - 9 SP - 3125 EP - 3132 PB - Springer CY - Berlin AN - OPUS4-23676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartoschewitz, R. A1 - Appel, P. A1 - Barrat, J.-A. A1 - Bischoff, A. A1 - Caffee, M.W. A1 - Franchi, I.A. A1 - Gabelica, Z. A1 - Greenwood, R.C. A1 - Harir, M. A1 - Harries, D. A1 - Hochleitner, R. A1 - Hopp, J. A1 - Laubenstein, M. A1 - Mader, B. A1 - Marques, R. A1 - Morlok, A. A1 - Nolze, Gert A1 - Prudêncio, M.I. A1 - Rochette, P. A1 - Ruf, A. A1 - Schmitt-Kopplin, P. A1 - Seemann, E. A1 - Szurgot, M. A1 - Tagle, R. A1 - Wach, R.A. A1 - Welten, K. C. A1 - Weyrauch, M. A1 - Wimmer, K. T1 - The Braunschweig meteorite − a recent L6 chondrite fall in Germany N2 - On April 23rd 2013 at 2:07 a.m., a 1.3 kg meteorite fell in the Braunschweig suburb Melverode (52° 13′ 32.19″ N. 10° 31′ 11.60″ E). Its estimated velocity was 250 km/h and it formed an impact pit in the concrete fall site with a diameter of 7 cm and a depth of 3 cm. Radial dust striae are present around the impact pit. As a result of the impact, the meteorite disintegrated into several hundred fragments with masses up to 214 g. The meteorite is a typical L6 chondrite, moderately shocked (S4) – but with a remarkably high porosity (up to 20 vol%). The meteorite was ejected from its parent body as an object with a radius of about 10–15 cm (15–50 kg). The U,Th-He gas retention age of ∼550 Ma overlaps with the main impact event on the L-chondrite parent body ∼470 Ma ago that is recorded by many shocked L chondrites. The preferred cosmic-ray exposure age derived from production of radionuclides and noble gas isotopes is (6.0 ± 1.3) Ma. KW - Braunschweig meteorite KW - L chondrite KW - Fall reconstruction KW - Petrology and mineralogy KW - Organic matter KW - IR spectroscopy KW - Bulk chemistry KW - Radionuclides KW - Noble gas isotopes KW - Specific heat PY - 2016 DO - https://doi.org/10.1016/j.chemer.2016.10.004 SN - 0009-2819 SN - 1611-5864 VL - 77 IS - 1 SP - 207 EP - 224 AN - OPUS4-42018 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -