An inter-comparison of 10Be and 26Al AMS reference standards and the 10Be half-life

摘要: Abstract We have completed a survey and inter-comparison of several 10 Be 26 Al standard reference materials (SRMs) that are in routine use at various AMS laboratories to assess their relative values the accuracy quoted nominal ratios. The accelerator measurement cycle, analysis procedure setup used ANTARES facility for this described. focused on new set serial dilutions prepared by Kuni Nishiizumii University California, Berkeley, found excellent systematic reproducibility internal consistency. For other materials, minor deviations evident even when results been recalibrated common half-life. In particular, we confirm NIST SRM-4325 has 14% greater Be/Be ratio than certified it is calibrated against SRMs whose ratios normalized 1.5 Ma order investigate apparent discrepancy, report an absolute, normalization independent, measure NIST-4325 ratio. Within constraints type its errors, determine absolute value range 26,050 24,800 × 10 −15 support 26,800 × 10 given NIST. hesitate directly infer as consequence half-life 1.34 Ma because such inference contingent direct accurate specific activity parent solution, which present not available.