Rood D.H.,Lawrence Livermore National Laboratory |
Rood D.H.,University of California at Santa Barbara |
Hall S.,University of California at Santa Cruz |
Guilderson T.P.,Lawrence Livermore National Laboratory |
And 4 more authors.
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2010
We determined the overall efficiency for 10Be of the high-intensity LLNL modified Middleton cesium sputter source in combination with the CAMS FN mass spectrometer. BeO- ionization efficiency is >3%. Charge exchange efficiency including transmission through the tandem for 7.5 MeV Be+3 is ∼34%, resulting in a total system efficiency of just over 1%. At this efficiency and with very low backgrounds, we estimate our detection limit to be ∼1000 10Be atoms. Cathodes prepared with only ∼80 μg of 9Be show only an ∼33% reduction in 9Be beam current compared to a sample with ∼200 μg. These same samples, prepared from 07KNSTD1032 standard material, contained 1 × 107 and 5 × 106 10Be atoms and exhibited similar ionization and total system efficiency. These results demonstrate the feasibility of pursuing applications that require precise measurement of samples with low 10Be concentrations and/or small sample size. © 2009 Elsevier B.V. Source