A multi-reflection time-of-flight (MR-ToF) device has been set up for the development and test of new MR-ToF techniques and for future applications in atomic cluster research. The instrument, consisting of a laser-ablation ion source, a quadrupole bender, the MR-ToF analyzer (with ion mirrors and in-trap lift), and a channeltron detector, is described in detail and characterized with respect to preliminary results of its performance parameters. In addition, cluster ions were mass selected in the MR-ToF device and photodissociated. The charged fragments were stored and mass analyzed in a proof-of-principle MS/MS experiment where both MS steps were performed in the MR-ToF operation mode.

Multi-reflection time-of-flight (MR-ToF) devices are established as mass separators and analyzers with high resolving powers and fast processing times. For ion injection and ejection, either the ion mirrors or an in-trap lift electrode has to be switched. In the present work, these two methods are combined with in-trap lift switching for ion capture and exit-side mirror switching for ejection with higher information content. Measurements are performed with small lead clusters to illustrate individual advantages of both techniques and the gain of combining them with focus on the ions' ToF ejection window. (C) 2017 Elsevier B.V. All rights reserved.

The former Berlin electron-beam ion trap (EBIT) has been moved to Greifswald. In addition to X-ray studies the setup will be used for the investigation of interaction processes between highly-charged ions and atomic clusters such as charge exchange and fragmentation. The EBIT setup has been reassembled and highlycharged ions have been produced from Xe-Ar gas mixtures to study the “sawtooth effect”. In addition, the layout of the extraction beamline, interaction region and product analysis for the interaction studies with highly-charged ions are presented. PACS numbers: 34.80.Dp, 52.58.Qv

The former Berlin electron-beam ion-trap was moved to Greifswald. One of the first aims after the reinstallation was the continuation of experiments using mixed ensembles of low- and high-Z ions for further studies of the previously reported sawtooth-like oscillations of the trap plasma. First results of these studies for xenon/argon mixtures are presented.

The former Berlin electron-beam ion trap (EBIT) was moved to Greifswald. In addition to x-ray studies the setup will be used for the investigation of interaction processes between highly charged ions and atomic clusters such as charge exchange and fragmentation. The EBIT setup has now been reassembled and highly charged ions have been produced from Xe–Ar gas mixtures to study the ‘sawtooth effect’. In addition, the layout of the extraction beamline, the interaction region and product analysis for interaction studies with highly charged ions are presented.

The g factor of the electron bound in hydrogenlike28Si13+ has been measured to 10 significant digits. The valueagrees very well with bound-state quantum-electrodynamical calculations and represents todate the most stringent test of the theory. The experiment uses a single ion confined in atriple Penning trap. Here we present details of the setup, the experimental procedure andthe data evaluation.

We determined the experimental value of the g factor of the electron bound in hydrogenlike ²⁸Si¹³⁺ by using a single ion confined in a cylindrical Penning trap. From the ratio of the ion's cyclotron frequency and the induced spin flip frequency, we obtain g = 1.995 348 958 7(5)(3)(8). It is in excellent agreement with the state-of-the-art theoretical value of 1.995 348 958 0(17), which includes QED contributions up to the two-loop level of the order of (Zα)² and (Zα)⁴ and represents a stringent test of bound-state quantum electrodynamics calculations.

We determined the experimental value of the g factor of the electron bound in hydrogenlike ²⁸Si¹³⁺ by using a single ion confined in a cylindrical Penning trap. From the ratio of the ion's cyclotron frequency and the induced spin flip frequency, we obtain g = 1.995 348 958 7(5)(3)(8). It is in excellent agreement with the state-of-the-art theoretical value of 1.995 348 958 0(17), which includes QED contributions up to the two-loop level of the order of (Zα)² and (Zα)⁴ and represents a stringent test of bound-state quantum electrodynamics calculations.

Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability.The mass and its inherent connection with the nuclear binding energy is a fundamental property of a nuclide, a unique "fingerprint". Thus, precise mass values are important for a variety of applications, ranging from nuclear-structure studies like the investigation of shell closures and the onset of deformation, tests of nuclear mass models and mass formulas, to tests of the weak interaction and of the Standard Model. The required relative accuracy ranges from 10(-5) to below 10(-8) for radionuclides, which most often have half-lives well below 1 s. Substantial progress in Penning trap mass spectrometry has made this method a prime choice for precision measurements on rare isotopes. The technique has the potential to provide high accuracy and sensitivity even for very short-lived nuclides. Furthermore, ion traps can be used for precision decay studies and offer advantages over existing methods.With MATS (Precision Measurements of very short-lived nuclei using an Advanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10(-9) can be reached by employing highly-charged ions and a non-destructive Fourier-Transform Ion-Cyclotron-Resonance (FT-ICR) detection technique on single stored ions. This accuracy limit is important for fundamental interaction tests, but also allows for the study of the fine structure of the nuclear mass surface with unprecedented accuracy, whenever required. The use of the FT-ICR technique provides true single ion sensitivity. This is essential to access isotopes that are produced with minimum rates which are very often the most interesting ones. Instead of pushing for highest accuracy, the high charge state of the ions can also be used to reduce the storage time of the ions, hence making measurements on even shorter-lived isotopes possible.Decay studies in ion traps will become possible with MATS. Novel spectroscopic tools for in-trap high-resolution conversion-electron and charged-particle spectroscopy from carrier-free sources will be developed, aiming e. g. at the measurements of quadrupole moments and E0 strengths. With the possibility of both high-accuracy mass measurements of the shortest-lived isotopes and decay studies, the high sensitivity and accuracy potential of MATS is ideally suited for the study of very exotic nuclides that will only be produced at the FAIR facility.Laser spectroscopy of radioactive isotopes and isomers is an efficient and model-independent approach for the determination of nuclear ground and isomeric state properties. Hyperfine structures and isotope shifts in electronic transitions exhibit readily accessible information on the nuclear spin, magnetic dipole and electric quadrupole moments as well as root-mean-square charge radii. The dependencies of the hyperfine splitting and isotope shift on the nuclear moments and mean square nuclear charge radii are well known and the theoretical framework for the extraction of nuclear parameters is well established. These extracted parameters provide fundamental information on the structure of nuclei at the limits of stability. Vital information on both bulk and valence nuclear properties are derived and an exceptional sensitivity to changes in nuclear deformation is achieved. Laser spectroscopy provides the only mechanism for such studies in exotic systems and uniquely facilitates these studies in a model-independent manner.The accuracy of laser-spectroscopic-determined nuclear properties is very high. Requirements concerning production rates are moderate; collinear spectroscopy has been performed with production rates as few as 100 ions per second and laser-desorption resonance ionization mass spectroscopy (combined with beta-delayed neutron detection) has been achieved with rates of only a few atoms per second.This Technical Design Report describes a new Penning trap mass spectrometry setup as well as a number of complementary experimental devices for laser spectroscopy, which will provide a complete system with respect to the physics and isotopes that can be studied. Since MATS and LaSpec require high-quality low-energy beams, the two collaborations have a common beamline to stop the radioactive beam of in-flight produced isotopes and prepare them in a suitable way for transfer to the MATS and LaSpec setups, respectively.

Individual hydrogen- and lithium-like ions with medium nuclear charge Z are confined in a cylindrical triple Penning trap for nearly unlimited time under well-controlled conditions in a small volume in space. We present progress in a project to determine the magnetic moment of the electron bound in Si13+ and Ca19+ and their Li-like counterparts. This serves for testing bound-state quantum electrodynamic calculations. Significant technical improvements will allow for higher precision than in the previous similar experiments on C5+ and O7+.

S. Sturm, A. Wagner† , K. Blaum, W. Quint, B. Schabinger, and G. Werth Institut für Physik, Johannes Gutenberg-Universität, D-55099 Mainz; MPI für Kernphysik, D-69117 Heidelberg, Germany; GSI, D-64291 Darmstadt, Germany Bound-state quantum electrodynamics (BS-QED) calculations can be tested by high-precision measurements of the gyromagnetic factor (g-factor) of the electron bound in highly-charged ions [1, 2]. Therefore, it is planned to measure the g-factor of lithiumand hydrogen-like silicon and calcium in a double Penning trap setup [3]. In the last year important steps towards the final g-factor measurement were made by developing new detection techniques and characterizing the two traps.

Individual charged atomic or molecular particles can be confined by electromagnetic fields for nearly unlimited times under well controlled conditions in a small volume in space. This allows performing spectroscopic experiments with unprecedented accuracy. We discuss a project to determine the magnetic moment of the electron bound in hydrogen-like ions with different nuclear charges. This serves for testing bound-state quantum-electrodynamics calculations with high precision. Previous results on C5+ and O7+ as well as the present status of the project with Si13+ and Ca19+ are presented in this contribution and future possibilities are discussed.

High-precision measurements of the magnetic moment of the electron bound in hydrogen-and lithium-like ions can be used to test bound-state quantum electrodynamical calculations. In the past measurements with relative experimental uncertainties as low as 2×10-9 were performed on hydrogen-like carbon and oxygen ions. In the current experiment we plan to measure the g-factor of hydrogen-like and lithium-like calcium ions. A relative uncertainty δg/g in the order of 10-9 is aspired. Here, we will give the motivation for the experiment, present the experimental techniques and first results.

Penning traps serve for the precise measurement of magnetic moments of simple atomic systems and fundamental particles. Here we present attempts to measure the magnetic moment of the electron bound in hydrogen-like or lithium-like heavy ions as well as of the proton and antiproton. While the first experiment aims for a more stringent test of bound-state quantum-electrodynamic calculations the second experiment provides a new high-precision test of the CPT theorem in the baryonic sector.

The precise determination of the anomalous magnetic moment of the electron bound in hydrogen-like ions allows for a stringent test of quantum electrodynamics (QED)in the presence of strong electric fields. g-factor measurements on the electron bound in hydrogen-like ions 12 C 5+ and 16 O 7+ , using single ions confined in a Penning trap, have yielded values in agreement with theory on the ppb level. If the QED calculations are considered correct, the results can in turn be used for a determination of fundamental constants like the electron mass m e , the fine structure constant α or nuclear parameters. We report about presentdevelopments towards g-factor measurements also in medium-heavy and heavy highly-charged ions.

Bound-state quantum electrodynamical calculations can be tested by high precision measurements of the magnetic moment of the electron bound in hydrogen-like and lithium-like ions. Measurements of hydrogen-like carbon and oxygen achieved relative experimental uncertainties as low as 2 x 10(-9). In the current experiment we plan to measure the g-factor of hydrogen-like and lithium-like calcium ions. The aim is to reach a relative uncertainty delta g/g in the order of 10(-9). Here, we will give the motivation for the experiment, present the experimental techniques and the status of the experiment.