Open AccessFurther improvement in the precision of 233U measurements by accelerator mass spectrometry at the Lawrence Livermore National Laboratory.
Author(s) -
Scott J. Tumey,
Thomas A. Brown,
T F Hamilton,
Bruce A. Buchholz
Publication year - 2008
Language(s) - English
Resource type - Reports
DOI - 10.2172/926045
Subject(s) - national laboratory , accelerator mass spectrometry , mass spectrometry , accuracy and precision , faraday cup , sample (material) , replicate , ion , nuclear engineering , analytical chemistry (journal) , physics , chemistry , engineering , chromatography , ion beam , engineering physics , mathematics , statistics , quantum mechanics
In response to sponsor interest in October 2005 we proposed two methods for enhancing the precision of {sup 233}U accelerator mass spectrometry (AMS) capabilities at the Lawrence Livermore National Laboratory (LLNL). In a previous report we evaluated the first method and demonstrated that by increasing sample loading by a factor of four coupled with performing four replicates of each sample, we could achieve measurement precision of {approx}1%. Recent modifications to our system have enabled us to test the second proposed method. By changing our setup to normalize {sup 233}U ions counted in a gas ionization chamber to {sup 238}U measured as a current in an off-axis Faraday cup we were able to attain 1% precision without the need for replicate analysis. This method could be further refined to achieve 0.5% precision in samples of interest