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For the measurement of the g-factor of the electron in extremely heavy ions, a novel cryogenic Penning trap, called ALPHATRAP, is currently set up at MPIK. It features an access to the Heidelberg EBIT [1], which can deliver even the heaviest highly charged ions up to 208Pb81+. With these systems it becomes possible to probe QED at the boundary of our knowledge in the most extreme fields. The ions are transported via a beamline including ion-optic elements and diagnostic stations to ALPHATRAP. There, the trap region is surrounded by a liquid-helium cryostat to provide a cryogenic environment. To ensure sufficient vacuum conditions for the storage of highly charged ions despite the connection to the room-temperature vacuum, a cryogenic vacuum valve is developed to cut the beamline off the trap setup.

Besides mechanical differences due to the open system most technical elements can in principal be adopted from the Mainz setup. However, adjustments are necessary for several issues. For instance, the higher charge states of the ions lead to a corresponding systematic shift of the ion frequencies due to the image-charge effect and, thus, a larger trap diameter is needed compared to the Mainz-trap. Another example is the even more complex and extensive detection system, which is currently under development.


[1] Optimization of the charge state distribution of the ion beam extracted from an EBIT by dielectronic recombination
J. R. Crespo López-Urrutia, J. Braun1, G. Brenner, H. Bruhns, A. Lapierre, A. J. González Martı́nez, V. Mironov, R. Soria Orts, H. Tawara, M. Trinczek and J. Ullrich
Rev. Sci. Instrum. 75, 1560 (2004) 


ERC Advanced Grant

This project receives funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme under grant agreement No 832848 - FunI.

9 High-Precision Determination of g Factors and Masses of 20Ne9+ and 22Ne9+

F. Heiße, M. Door, T. Sailer, P. Filianin, J. Herkenhoff, C. M. König., K. Kromer, D. Lange, J. Morgner, A. Rischka, C.. Schweiger, B. Tu, Y. N. Novikov, S. Eliseev, S. Sturm, and K. Blaum
Physical Review Letters 131, 253002 (2023)

8 Stringent test of QED with hydrogen-like tin

J. Morgner, B. Tu, C. M. König., T. Sailer, F. Heiße, H. Bekker, B. Sikora, C. Lyu, V. A. Yerokhin, Z. Harman, J. R. Crespo López-Urrutia, C. H. Keitel, S. Sturm, and K. Blaum
Nature 622, 53-57 (2023)
 MPIK press release: Precise testing of quantum electrodynamics
 MPIK-Pressemitteilung: Quantenelektrodynamik auf dem Prüfstand
 MPG press release: When the laws of physics are at stake - Quantum electrodynamics put to the test
 MPG-Presssemitteilung: Wenn Gesetze der Physik auf dem Spiel stehen - Quantenelektrodynamik auf dem Prüfstand
 Nature research briefings: Testing the limits of the standard model of particle physics with a heavy, highly charged ion A precise test of quantum electrodynamics: Measuring the g factor of electrons in hydrogen-like tin

7 Measurement of the bound-electron g-factor difference in coupled ions

T. Sailer, V. Debierre, Z. Harman, F. Heiße, C. König, J. Morgner, B. Tu, A. V. Volotka, C. H. Keitel, K. Blaum, and S. Sturm
Nature 606, 479-483 (2022)
 Nature News & Views: Tiny isotopic difference tests standard model of particle physics
 MPIK press release: Quantum electrodynamics tested 100 times more accurately
 MPIK-Pressemitteilung: Quantenelektrodynamik 100-fach genauerer getestet Quantum electrodynamics tested 100 times more accurately than ever Präzisionsprüfung der Quantenelektrodynamik

6 Tank-Circuit Assisted Coupling Method for Sympathetic Laser Cooling

B. Tu, F. Hahne, I. Arapoglou, A. Egl, F. Heiße, M. Höcker, C. König, J. Morgner, T. Sailer, A. Weigel, R. Wolf, and S. Sturm
Advanced Quantum Technologies 4, 2100029 (2021)

5 Perspectives on testing fundamental physics with highly charged ions in Penning traps

K. Blaum, S. Eliseev, and S. Sturm
Quantum Science and Technology 6, 014002 (2020)

4 g Factor of Lithiumlike Silicon: New Challenge to Bound-State QED

D. A. Glazov, F. Köhler-Langes, A. V. Volotka, K. Blaum, F. Heiße, G. Plunien, W. Quint, S. Rau, V. M. Shabaev, S. Sturm, and G. Werth
Physical Review Letters 123, 173001 (2019)

3 Application of the Continuous Stern-Gerlach Effect for Laser Spectroscopy of the 40Ar13+ Fine Structure in a Penning Trap

A. Egl, I. Arapoglou, M. Höcker, K. König, T. Ratajczyk, T. Sailer, B. Tu, A. Weigel, K. Blaum, W. Nörtershäuser, and S. Sturm
Physical Review Letters 123, 123001 (2019)

2 g Factor of Boronlike Argon 40Ar13+

I. Arapoglou, A. Egl, M. Höcker, T. Sailer, B. Tu, A. Weigel, R. Wolf, H. Cakir, V. A. Yerokhin, N. S. Oreshkina, V. A. Agababaev, A. V. Volotka, D. V. Zinenko, D. A. Glazov, Z. Harman, C. H. Keitel, S. Sturm, and K. Blaum
Physical Review Letters 122, 253001 (2019) Alphatrap-Experiment liefert erste Ergebnisse
 idw press release: First results of the new Alphatrap experiment
 MPIK-Pressemitteilung: Erste Resultate des neuen ALPHATRAP-Experiments

1 The ALPHATRAP experiment

S. Sturm, I. Arapoglou, A. Egl, M. Höcker, S. Kraemer, T. Sailer, B. Tu, A. Weigel, R. Wolf, J. R. Crespo López-Urrutia, and K. Blaum
European Physical Journal - Special Topics 227, 1425-1491 (2019)