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PDF, English - main document Download (74MB) | Lizenz: Injection of Highly Charged Ion Ensembles for Spectroscopy of Magnetic Interactions in the ARTEMIS Penning Trap by Klimes, Jeffrey underlies the terms of Creative Commons Attribution 4.0

Abstract

Quantum electrodynamics (QED) is the most precisely validated theory in modern physics, yet it remains mostly untested in the most extreme fields. In addition, atomic nuclei generate fields much stronger than can be made in even the most advanced laser and magnet facilities. Therefore, heavy highly charged ions (HCIs) present themselves as natural laboratories for investigating QED in strong fields. ARTEMIS is a Penning trap experiment designed for measurement of electron and nuclear magnetic moments in heavy HCIs using laser-microwave double-resonance (LMDR) spectroscopy. This technique enables measurement of magnetic moments in atomic systems with hyperfine structure, in which the transitions are often in the near ultraviolet (UV) regime such as hydrogenlike bismuth, 209Bi82+. Precision spectroscopy of such heavy, HCIs requires an exceedingly well isolated trapping environment with vacuum pressure better than 10−15 mbar. This work presents the implementation of the first ion trap capable of long-term storage of heavy HCIs with a residual gas pressure better than 2.4x10−16 mbar and with rapid cycle times as fast as 100 ms for irradiation with UV laser light, as well as the design of the corresponding injection beamline. The trapping conditions are verified by non-destructive monitoring of trapped HCIs over a few days, which were ultimately stored for about 2 weeks. The operation of such a fast-opening cryogenic valve (FCV) is essential to the LMDR technique for many heavy ion systems where excellent environmental conditions in the trapping region and direct line of sight for laser irradiation are required.