SMILETRAP - Atomic mass measurements with ppb accuracy by using highly charged ions

In the SMILETRAP facility externally produced highly charged ions are captured in a Penning trap and utilized for high precision measurements of atomic masses. Accuracy tests on a ppb level have been performed, using highly charged carbon, oxygen and neon ions. In all cases hydrogen ions served as a reference for the calibration and monitoring of the magnetic field in the trap. Deviations smaller than 3 ppb from the expected results were found in mass measurements of the O-16 and Ne-20 atomic masses. The proton atomic mass, determined from the reference measurements on hydrogen ions, is in good agreement with the accepted value [1]. A direct mass measurement on the Kr-86-isotope, using trapped Kr-86(29)-ions is reported.