The French accelerator mass spectrometry facility ASTER: Improved performance and developments

After the installation and acceptance test of the French 5 MV AMS facility ASTER, the focus has been on improving ¹⁰Be and ²⁶Al routine measurements. Quality assurance was established by introducing traceable AMS standards for each nuclide, self-monitoring by taking part in round-robin exercises and proficiency testing, and surveillance of long- and short-time variability of blank and reference materials. A background level of 3x10^-14 makes ASTER well-suited for measuring ⁴¹Ca/⁴⁰Ca in the 10^-12 region, which is sufficient for a wide range of applications. Routine AMS measurements of volatile elements like ³⁶Cl and ¹²⁹I are most likely feasible in the very near future after sophisticated ion source improvements took place.