T01_03

Radiocarbon AMS below 100 keV

Maxeiner S¹,  Synal H², De Maria D², Wacker L², Müller A², Fahrni S¹, Suter M²

¹Ionplus AG, Dietikon, Switzerland, ²Laboratory of Ion Beam Physics, ETH Zurich, Zurich, Switzerland

New technologies such as He-stripping have enabled the miniaturization and simplification of compact accelerator mass spectrometry (AMS) systems over the last two decades. As one of the most compact AMS systems, the MICADAS was optimized for stripping energies of around 240 keV and provides precise and efficient radiocarbon measurements for more than 15 years. In a collaboration between ETH Zurich and Ionplus AG, a new ultra-compact radiocarbon AMS system has been developed. It is based on many of the principles of MICADAS and operates near or at the physical limits of efficient radiocarbon AMS with stripping energies of around 100 keV. Measurements performed with an early prototype system showed that, despite the much lower beam energies, highly efficient, sensitive, and precise measurements comparable to MICADAS are possible. The technical challenges at such low voltages and the measurement results with different prototype configurations will be discussed and a new commercial product will be presented: the Low Energy Accelerator (“LEA”). With a footprint of 2.6 m x 1.8 m and with a tandem acceleration voltage of 50 kV, LEA is expected to perform similarly to the MICADAS at less than half its energy.