Publications
| 2024 | Precision spectroscopy on 9Be overcomes limitations from nuclear structure Stefan Dickopf, Bastian Sikora, Annabelle Kaiser, Marius Müller, Stefan Ulmer, Vladimir A. Yerokhin, Zoltán Harman, Christoph H. Keitel, Andreas Mooser, Klaus Blaum
Orders of Magnitude Improved Cyclotron-Mode Cooling for Non-Destructive Spin Quantum Transition Spectroscopy with Single Trapped Antiprotons |
| BM Latacz, M Fleck, JI Jaeger, G Umbrazunas, BP Arndt, SR Erlewein, ... | |
| Phys. Rev. Lett. 133, 053201 (2024) | |
| Image-current mediated sympathetic laser cooling of a single proton in a Penning trap down to 170 mK axial temperature | |
| C. Will, M. Wiesinger, P. Micke, H. Yildiz, T. Driscoll, S. Kommu, F. Abbass, B. P. Arndt, B. B. Bauer, S. Erlewein, M. Fleck, J. I. Jäger, B. M. Latacz, A. Mooser, D. Schweitzer, G. Umbrazunas, E. Wursten, K. Blaum, J. A. Devlin, C. Ospelkaus, W. Quint, A. Soter, J. Walz, C. Smorra, S. Ulmer | |
| Phys. Rev. Lett. 133, 023002 (2024) | |
| Terrestrial very-long-baseline atom interferometry: Workshop summary | |
S Abend, B Allard, I Alonso, J Antoniadis, H Araújo, G Arduini, AS Arnold, ... | |
| AVS Quantum Science 6 (2), 2024 | |
| 2022 | A High-Q Superconducting Toroidal Medium Frequency Detection System with a Capacitively Adjustable Frequency Range >180 kHz. |
| F. Voelksen, M. J. Borchert, J. A. Devlin, S. Erlewein, M. Fleck, J. A. Harrington, B. Latacz, E. Wursten, A. H. Mooser, M. A. Bohman, V. Grunhofer, C. Smorra, M. Wiesinger, C. Will, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki, S. Ulmer | |
| Review of Scientific Instruments (akzeptiert, 2022) | |
| Direct Measurement of the 3He magnetic moments | |
| A. Schneider, B. Sikora, S. Dickopf, M. Müller, N. S. Oreshkina, A. Rischka, I. A. Valuev, S. Ulmer, J. Walz, Z. Harman, C. H. Keitel, A. Mooser & K. Blaum | |
| Nature 606, 878 (2022) | |
| Millicharged Dark Matter Detection with Ion Traps | |
| D. Budker, P. W. Graham, H. Ramani, F. Schmidt-Kaler, C. Smorra, and S. Ulmer | |
| PRX-Quantum 3, 010330 (2022). | |
| A 16 parts-per-trillion measurement of the antiproton-to-proton charge-mass ratio | |
| M. J. Borchert, J. A. Devlin, S. Erlewein, M. Fleck, J. A. Harrington, B. Latacz, E. Wursten, A. H. Mooser, M. A. Bohman, V. Grunhofer, C. Smorra, M. Wiesinger, C. Will, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki, S. Ulmer | |
| Nature 601, 53 (2022) | |
| 2021 | LC circuit mediated sympathetic cooling of a proton via image currents |
| M. A. Bohman, V. Grunhofer, C. Smorra, M. Wiesinger, C. Will, M. J. Borchert, J. A. Devlin, S. Erlewein, M. Fleck, J. A. Harrington, B. Latacz, E. Wursten, A. H. Mooser, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki, S. Ulmer | |
| Nature 596, 514 (2021) | |
| Quantum logic inspired techniques for spacetime-symmetry tests with (anti-)protons | |
| J. M. Cornejo, R. Lehnert, M. Niemann, J. Mielke, T. Meiners, A. Bautista-Salvador, M. Schulte, D. Nitzschke, M. J. Borchert, K. Hammerer, S. Ulmer, C. Ospelkaus | |
| New Journal of Physics 23, 073045 (2021) | |
| Constraints on the coupling between axion-like dark matter and photons using an antiproton superconducting tuned detection circuit in a cryogenic Penning trap | |
| J. A. Devlin, M. J. Borchert, S. Erlewein, M. Fleck, J. A. Harrington, B. Latacz, J. Warncke, E. Wursten, M. A. Bohman, A. H. Mooser, C. Smorra, M. Wiesinger, C. Will, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki, S. Ulmer | |
| Phys. Rev. Lett. 126, 041301 (2021) | |
| Measurement of the Principal Quantum Number Distribution in a Beam of Antihydrogen Atoms | |
| B. Kolbinger et al. (ASACUSA collaboration) | |
| EPJD 75, 91 (2021) | |
| 2020 | Detection of Metastable Electronic States by Penning Trap Mass Spectrometry |
| R. X. Schüssler, H. Bekker,, M. Braß, H. Cakir, J. R. Crespo López-Urrutia, M. Door, P. Filianin, Z. Harman, M. W. Haverkort, W. J. Huang, P. Indelicato, C. H. Keitel, C. M. König, K. Kromer, M. Müller, Y. N. Novikov, A. Rischka, C. Schweiger, S. Sturm, S. Ulmer, S. Eliseev, K. Blaum | |
| Nature 581, 64 (2020) | |
| Elementary Laser-Less Quantum Logic Operations with Single (Anti-)Protons in Penning Traps | |
| M. Niemann, T. Meiners, J. Mielke, M. J. Borchert, J. M. Cornejo, S. Ulmer and C. Ospelkaus | |
| Advanced Quantum Technologies 3, 1900133 (2020) | |
| 2019 | Cryogenic Be+ Penning Trap for Precision Measurements with Antiprotons |
| M. Niemann, T. Meiners, J. Mielke, M. J. Borchert, J. M. Cornejo, S. Ulmer and C. Ospelkaus | |
| Measurement Science and Technology 31, 035003 (2019) | |
| Direct Limits on the Interaction of Antiprotons with Axion-Like Dark Matter | |
| C. Smorra, Y. Stadnik, M. Bohman, M. J. Borchert, S. Erlewein, J. A. Harrington, J. A. Devlin, P.E. Blessing, T. Higuchi, M. Wiesinger, G. Schneider, A. Mooser, K. Blaum, Y. Matsuda, W. Quint, J. Walz, D. Budker, and S. Ulmer | |
| Nature 575, 310 (2019) | |
| Measurement of Ultra-Low Heating Rates in a Cryogenic Penning Trap | |
| M. J. Borchert, P.E. Blessing, J.A. Devlin, J. A. Harrington, T. Higuchi, J. Morgner, E. Wursten, M. Bohman, M. Wiesinger, C. Smorra, K. Blaum, Y. Matsuda, W. Quint, J. Walz, and S. Ulmer | |
| Phys. Rev. Lett. 122, 043201 (2019) | |
| A Novel Penning Trap Design for the High Precision Measurement of the 3He2+ Nuclear Magnetic Moment | |
| A. Schneider, A. Mooser, A. Rischka, K. Blaum, S. Ulmer, J. Walz | |
| Ann. Phys. (Berlin) 531, 1800485 (2019) | |
| Superconducting Solenoid System with Adjustable Shielding Factor for Precision measurements of the Properties of the Antiprotons | |
| J.A. Devlin, E. Wursten, J. A. Harrington, M. J. Borchert, P.E. Blessing, T. Higuchi, J. Morgner, M. Bohman, M. Wiesinger, C. Smorra, K. Blaum, Y. Matsuda, W. Quint, J. Walz, and S. Ulmer | |
| Phys. Rev. Appl. 12, 044012 (2019) | |
| 2018 | Challenging the Standard Model by high precision comparisons of the fundamental properties of protons and antiprotons |
| S. Ulmer, A. Mooser, H. Nagahama, S. Sellner, C. Smorra | |
| Phil.Trans.R.Soc.A 376, 20170275 (2017) | |
| The ASACUSA antihydrogen and hydrogen program: results and prospects | |
| C. Malbrunot, et. al. (ASACUSA collaboration) | |
| Phil. Trans. R. Soc. A 376: 20170273 | |
| Imaging antimatter with a Micromegas detector | |
| V. Mäckel et al. (ASACUSA collaboration) | |
| Nucl. Instrum. Meth. B 422, 1 (2018) | |
| 2017 | Sympathetic cooling of protons and antiprotons with a common endcap Penning trap |
| M. Bohman, G. Schneider, A. Mooser, N. Schön, J. Harrington, T. Higuchi, H. Nagahama, S. Sellner, C. Smorra, K. Blaum, Y. Matsuda, W. Quint, J. Walz, S. Ulmer | |
| Journ. Mod. Opt. DOI: 10.1080/09500340.2017.1404656 (2017) | |
| Double-trap measurement of the proton magnetic moment at 0.3 parts per billion precision | |
| G. Schneider, A. Mooser, M. Bohman, N. Schön, J. Harrington, T. Higuchi, H. Nagahama, S. Sellner, C. Smorra, K. Blaum, Y. Matsuda, W. Quint, J. Walz, S. Ulmer | |
| Science 358, 1081 (2017) | |
| A parts-per-billion measurement of the antiproton magnetic moment | |
| C. Smorra, S. Sellner, M. J. Borchert, J. A. Harrington, T. Higuchi, H. Nagahama, T. Tanaka, A. Mooser, G. Schneider, M. Bohman, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki and S. Ulmer | |
| Nature 550, 371-374 (2017) | |
| Improved limit on the directly measured antiproton lifetime | |
| S. Sellner, M. Besirli, M. Bohman, M.J. Borchert, J. Harrington, T. Higuchi, A. Mooser, H. Nagahama, G. Schneider, C. Smorra, T. Tanaka, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki and S. Ulmer | |
| New J. Phys. 19 083023 (2017) | |
| High-Precision Measurement of the Proton’s Atomic Mass | |
| F. Heiße, F. Köhler-Langes, S. Rau, J. Hou, S. Junck, A. Kracke, A. Mooser, W. Quint, S. Ulmer, G. Werth, K. Blaum, and S. Sturm | |
| Phys. Rev. Lett. 119, 033001 (2017) | |
| Observation of individual spin quantum transitions of a single antiproton | |
| C. Smorra, A. Mooser, M. Besirli, M. Bohman, M. J. Borchert, J. Harrington, T. Higuchi, H. Nagahama, T. Tanaka, S. Sellner, G. Schneider, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki, and S. Ulmer | |
| Phys. Lett. B 769, 1 (2017) | |
| Optical transition seen in antihydrogen | |
| S. Ulmer | |
| Nature 541, 467 (2017) | |
| Sixfold improved single particle measurement of the magnetic moment of the antiproton | |
| H. Nagahama, C. Smorra, S. Sellner, J. Harrington, T. Higuchi, M. J. Borchert, T. Tanaka, M. Besirli, A. Mooser, G. Schneider, K. Blaum, Y. Matsuda, C. Ospelkaus, W. Quint, J. Walz, Y. Yamazaki, and S. Ulmer | |
| Nat. Commun. 8 14084 (2017) | |
| 2016 | Highly sensitive superconducting circuits at 700 kHz with tunable quality factors for image-current detection of single trapped antiprotons. |
| H. Nagahama, G. Schneider, A. Mooser, M. Besirli, M. J. Borchert, K. Blaum, J. Harrington, T. Higuchi, Y. Matsuda, C. Ospelkaus, W. Quint, S. Sellner, C. Smorra, T. Tanaka, J. Walz, Y. Yamazaki, and S. Ulmer | |
| Rev. Sci. Instrum. 87 113305 (2016) | |
| 2015 | The ASACUSA-CUSP, an antihydrogen experiment |
| N. Kuroda et al. | |
| DOI 10.1007/s10751-015-1205-1 | |
| High-precision comparison of the antiproton-to-proton charge-to-mass ratio | |
| S. Ulmer, C. Smorra, A. Mooser, K. Franke, H. Nagahama, G. Schneider, T. Higuchi, S. Van Gorp, K. Blaum, Y. Matsuda, W. Quint, J. Walz, Y. Yamazaki | |
| Nature 524, 196 (2015) | |
| BASE - The Baryon Antibaryon Symmetry Experiment | |
| C. Smorra, K. Blaum, L. Bojtar, M. Borchert, K. A. Franke, T. Higuchi, N. Leefer, H. Nagahama, Y. Matsuda, A. Mooser, M. Niemann, C. Ospelkaus, W. Quint, G. Schneider, S. Sellner, T. Tanaka, S. Van Gorp, J. Walz, Y. Yamazaki, S. Ulmer | |
| Eur. Phys. J. Special Topics 224, 3055 (2015) | |
| Das magnetische Moment des Protons | |
| A. Mooser, C. Smorra, S. Ulmer | |
| PhiuZ 46, 92 (2015) | |
| A reservoir trap for antiprotons | |
| C. Smorra, A. Mooser, K. Franke, H. Nagahama, G. Schneider, T. Higuchi, S. V. Gorp, K. Blaum, Y. Matsuda, W. Quint, J. Walz, Y. Yamazaki, S. Ulmer | |
| Int. J. Mass. Spectrom. 389, 10 (2015) | |
| The development of the antihydrogen beam detector and the detection of the antihydrogen atoms for in-flight hyperfine spectroscopy | |
| Y. Nagata et al. | |
| Journ. Phys. Conf. Ser. 635, 022061 (2015) | |
| Precise Tests of Fundamental Symmetries with Exotic Particles in Penning Traps | |
| S. Ulmer, W. Quint and K. Blaum | |
| World Scientific Books, Lecture Notes (2015) | |
| 2014 | Towards a high-precision measurement of the antiproton magnetic moment |
| C. Smorra, K. Blaum, K. Franke, Y. Matsuda, A. Mooser, H. Nagahama, C. Ospelkaus, W. Quint, G. Schneider, S. Van Gorp, J. Walz, Y. Yamazaki, S. Ulmer | |
| Hyp. Int. 228, 31 (2014) | |
| Direct high-precision measurement of the magnetic moment of the proton | |
| A. Mooser, S. Ulmer, K. Blaum, K. Franke, H. Kracke, C. Leiteritz, W. Quint, C. C. Rodegheri, C. Smorra, und J. Walz | |
| Nature 509, 596 (2014) | |
| The magnetic moments of the proton and the antiproton | |
| S. Ulmer, A. Mooser, K. Blaum, S. Braeuninger, K. Franke, H. Kracke, C. Leiteritz, Y. Matsuda, H. Nagahama, C. Ospelkaus, C. C. Rodegheri, W. Quint, G. Schneider, C. Smorra, S. Van Gorp, J. Walz und Y. Yamazaki | |
| J. Phys.: Conf. Ser. 488, 012033 (2014) | |
| A Source of Antihydrogen for In-Flight Hyperfine Spectroscopy | |
| N. Kuroda, S. Ulmer, D. J. Murtagh, S. Van Gorp, Y. Nagata, et al. | |
| Nature Communications 5, 3089 (2014) | |
| The magnetic moments of the proton and the antiproton | |
| S. Ulmer and C. Smorra | |
| Book chapter in: PRECISION SPECTROSCOPY IN ION TRAPS FOR FUNDAMENTAL PHYSICS, Editors: W. Quint and M. Vogel (Springer 2014) | |
| Towards a spin polarized antihydrogen beam | |
| N. Kuroda et al. | |
| Hyperfine Interactions 228, 67 (2014) | |
| 2013 | Demonstration of the double Penning trap technique with a single proton |
| A. Mooser, S. Bräuninger, K. Franke, H. Kracke, C. Leiteritz, C.C. Rodegheri, H. Nagahama, G. Schneider, C. Smorra, K. Blaum, Y. Matsuda, W. Quint, J. Walz, Y. Yamazaki, S. Ulmer | |
| Phys. Lett. B 723, 78 (2013) | |
| Resolution of single spin flips of a single proton | |
| A. Mooser, H. Kracke, K. Blaum, S. A. Bräuninger, K. Franke, C. Leiteritz, W. Quint, C. C. Rodegheri, S. Ulmer, und J. Walz | |
| Phys. Rev. Lett. 110, 140405 (2013) | |
| A cryogenic detection system at 28.9 MHz for the non-destructive observation of a single proton at low particle energy | |
| S. Ulmer, K. Blaum, H. Kracke, A. Mooser, W. Quint, C.C. Rodegheri, J. Walz | |
| Nucl. Instrum. Methods A 705, 55 (2013) | |
| CPT symmetry tests with cold antiprotons and antihydrogen | |
| Y. Yamazaki and S. Ulmer | |
| Ann. d. Phys. 525, 493 (2013) | |
| Resolution of Single Spin-Flips of a Single Proton | |
| A. Mooser, H. Kracke, K. Blaum, S. A. Braeuninger, K. Franke, C. Leiteritz, W. Quint, C. C. Rodegheri, S. Ulmer, J. Walz | |
| Phys. Rev. Lett. 110, 140405 (2013) | |
| Measurement of the Hyperfine Structure of Antihydrogen in a Beam | |
| E. Widmann, M. Diermaier, B. Juhász, C. Malbrunot, O. Massiczek, C. Sauerzopf, K. Suzuki, B. Wünschek, J. Zmeskal, S. Federmann, N. Kuroda, S. Ulmer, Y. Yamazaki | |
| Hyp. Int. 215, 1 (2013) | |
| 2012 | An experiment for the direct determination of the g-factor of a single proton in a Penning trap |
| C. C. Rodegheri, K. Blaum, H. Kracke, S. Kreim, A. Mooser, W. Quint, S. Ulmer und J. Walz | |
| New J. Phys. 14, 063011 (2012) | |
| 2011 | Direct measurement of the free cyclotron frequency of a single particle in a Penning trap |
| S. Ulmer, K. Blaum, H. Kracke, A. Mooser, W. Quint, C. C. Rodegheri, und J. Walz | |
| Phys. Rev. Lett. 107, 103002 (2011) | |
| Observation of spin flips with a single trapped proton | |
| S. Ulmer, C. C. Rodegheri, K. Blaum, H. Kracke, A. Mooser, W. Quint, und J. Walz | |
| Phys. Rev. Lett. 106, 253001 (2011) | |
| Towards a direct measurement of the g-factor of a single isolated proton | |
| A. Mooser, K. Blaum, H. Kracke, S. Kreim, W. Quint, C. C. Rodeghéri, S. Ulmer, und J. Walz | |
| Can. J. Phys. 89, 165 (2011) | |
| 2009 | The quality factor of a superconducting rf resonator in a magnetic field |
| S. Ulmer, H. Kracke, K. Blaum, S. Kreim, A. Mooser, W. Quint, C. C. Rodegheri, und J. Walz | |
| Rev. Sci. Instrum. 80, 123302 (2009) | |
| Developments for the direct determination of the g-factor of a single proton in a Penning trap | |
| C. C. Rodegheri, K. Blaum, H. Kracke, S. Kreim, A. Mooser, C. Mrozik, W. Quint, S. Ulmer und J. Walz | |
| Hyp. Int. 194, 93 (2009) | |
| g-factor experiments on simple systems in Penning traps | |
| K. Blaum, H. Kracke, S. Kreim, A. Mooser, C. Mrozik, W. Quint, C. C. Rodegheri, B. Schabinger, S. Sturm, S. Ulmer, A. Wagner, J. Walz und G. Werth | |
| J. Phys. B: At. Mol. Opt. Phys. 42, 154021 (2009) | |
| Recent developments in ion detection techniques for Penning trap mass spectrometry at Triga-Trap | |
| J. Ketelaer, K. Blaum, M. Block, K. Eberhardt, M. Eibach, R. Ferrer, S. George, F. Herfurth, J. Ketter, Sz. Nagy, J. Repp, L. Schweikhard, C. Smorra, S. Sturm, and S. Ulmer | |
| Eur. Phys. J. A 42, 311–317 (2009) | |
| Older Calculation of electrostatic fields using quasi-Green's functions: application to the hybrid Penning trap | |
| J. Verdú, S. Kreim, K. Blaum, H. Kracke, W. Quint, S. Ulmer, and J. Walz | |
| New J. Phys. 10, 103009-1 - 103009-23 (2008) | |
| Penning trap measurement of the magnetic moment of the antiproton | |
| J. Verdú, K. Blaum, S. Djekic, S. Kreim, W. Quint, S. Stahl, S. Ulmer, M. Vogel, J. Walz, G. Werth | |
| AIP Conference Proceedings 796, 260-265 (2005) | |
| Technical Documents | |
| BASE Letter of Intent, BASE Technical Design Report, BASE Annual Reports and BASE future proposal are found on CERN’s document server. | |
| BASE – Future Proposal | |
| S. Ulmer et al. | |
| CERN Document server: https://cds.cern.ch/record/2702758 (2019) | |
| This document contains the full future program of the BASE collaboration at CERN, which was approved by CERN’s SPSC committee in January 2020 | |
| Technical Design Report BASE | |
| S. Ulmer et al. | |
| CERN Document server: http://cds.cern.ch/record/1503514 (2013) | |
| Letter of Intent: Direct high-precision measurement of the g-factor of a single antiproton stored in a cryogenic Penning trap | |
| S. Ulmer et al. | |
| CERN Document server: https://cds.cern.ch/record/1455847 (2012) | |
| Annual Progress Reports on BASE are available on the CERN Document Server |