Separated Oscillatory Fields for High-Precision Penning Trap Mass Spectrometry

George, S.; Baruah, S.; Blank, B.; Blaum, K.; Breitenfeldt, M.; Hager, U.; Herfurth, F.; Herlert, A.; Kellerbauer, A.; Kluge, H. J.; Kretzschmar, M.; Lunney, D.; Savreux, R.; Schwarz, S.; Schweikhard, L.; Yazidjian, C.

Separated Oscillatory Fields for High-Precision Penning Trap Mass Spectrometry

Authors

Description

Ramsey's method of separated oscillatory fields is applied to the excitation of the cyclotron motion of short-lived ions in a Penning trap to improve the precision of their measured mass. The theoretical description of the extracted ion-cyclotron-resonance line shape is derived out and its correctness demonstrated experimentally by measuring the mass of the short-lived $^{38}$Ca nuclide with an uncertainty of $1.6\cdot 10^{-8}$ using the ISOLTRAP Penning trap mass spectrometer at CERN. The mass value of the superallowed beta-emitter $^{38}$Ca is an important contribution for testing the conserved-vector-current hypothesis of the electroweak interaction. It is shown that the Ramsey method applied to mass measurements yields a statistical uncertainty similar to that obtained by the conventional technique ten times faster.
5 pages, 4 figures, 0 tables