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Trapping devices for atomic and nuclear physics experiments with radioactive ions are becoming more and more important at accelerator facilities. While about ten years ago only one online Penning trap experiment existed, namely ISOLTRAP at ISOLDE/CERN, meanwhile almost every radioactive beam facility has installed or plans an ion trap setup. This article gives an overview on ion traps in the operation, construction or planing phase which will be used for fundamental studies with short-lived radioactive nuclides such as mass spectrometry, laser spectroscopy and nuclear decay spectroscopy. In addition, this article summarizes the use of gas cells and radiofrequency quadrupole (Paul) traps at different facilities as a versatile tool for ion beam manipulation like retardation, cooling, bunching, and cleaning. [Copyright &y& Elsevier]

The highest precision in mass measurements on short-lived radionuclides is obtained using trapping and cooling techniques. Here, the experimental storage ring (ESR) at GSI/Darmstadt and the tandem Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN play an important role. Status and recent results on mass measurements of radioactive nuclides with ESR and ISOLTRAP are summarized. [Copyright &y& Elsevier]

The investigation of simple atomic systems in extreme electromagnetic fields with highest precision demands intense beams of heavy and highly charged ions to be decelerated and cooled to extremely low energies for long-time observation. Resistive cooling, i.e., the electronic dissipation of energy of a stored ion cloud on an external impedance, seems to be a good candidate for in-trap cooling of highly charged ions and has been chosen for the upcoming HITRAP (Highly charged Ion TRAP) facility at GSI, Darmstadt. Nevertheless, resistive cooling of large ensembles of ions confined in a Penning trap has never been thoroughly studied until now and the understanding of this highly nonlinear phenomenon is far from complete. Through the use of systematic simulations we give a proof of the feasibility of resistive cooling of large numbers of highly charged ions as well as the interpretation of some specific features observed experimentally. [ABSTRACT FROM AUTHOR]

The present work is concerned with the association of a temperature to a single ion stored in a Penning ion trap. Several methods are described which allow to determine the temperature by measurements of the ion’s cyclotron and axial trapping frequencies. Recent results of a measurement on a hydrogen-like carbon ion12C5 + by use of mode coupling are presented and possible further applications are discussed. [ABSTRACT FROM AUTHOR]

A common approach to wavelength measurement is the travelling interferometer (wavemeter). We present an evaluation procedure that allows to achieve high precision with a compact device. The zero crossings of the interference signal corresponding to the reference laser is used to sample the signal of the probe laser. Electronic noise and fluctuations of the laser frequency cancel due to the large number of sample points. The evaluation procedure has been applied to a wavemeter based on a continuously moving Mach–Zehnder interferometer. A travelling path of 10 cm was sufficient to yield 3σ-accuracy of Δλ/λ=3.2×10−9, demonstrated by comparison with cesium saturation spectroscopy. [Copyright &y& Elsevier]

Precise mass calibration is mandatory in many fields of mass spectrometry. We have performed laser desorption/ionization cluster studies with a MALDI-TOF mass spectrometer on gold and fullerene targets to produce atomic clusters. These investigations demonstrate that clusters are ideally suited for this purpose. Pulsed N2-laser and Nd:YAG-laser ablation was used to produce positively as well as negatively charged clusters. Earlier observations of dianionic metal clusters are confirmed. First results from the tandem Penning trap mass spectrometer ISOLTRAP using carbon clusters as mass references show how carbon clusters can be applied to precision mass spectrometry by providing absolute mass standards. [ABSTRACT FROM AUTHOR]

A new type of resonance ionization laser ion source, which shall combine the advantages of a laser ion source with those of an ion trap, is proposed. The primary purpose of such a laser ion source trap, which is based on a gas-filled linear radio-frequency quadrupole ion trap system, is the decoupling of evaporation and ionization processes. Furthermore optimum temporal control on the generated ion bunch is obtained. Both effects will lead to a significantly increased isobaric selectivity and ion beams of low emittance. A large variety of operational modes, ranging from quasi-dc to microseconds-bunched radioactive ion beams with variable pulse width and repetition rate, can be chosen freely and beam energies can easily be altered. The principles and the layout of LIST will be discussed on the basis of atom and ion trajectory simulations and resulting performance parameters. [Copyright &y& Elsevier]

The design of a novel electrode structure for electric-field ionization of Rydberg atoms in a fast atomic beam is described. It allows the resolution of the ion signal from Rydberg atoms with adjacent effective principal quantum numbers n[sup *] in the range of 14≤n[sup *]≤40 and minimizes the volume where field ionization takes place. These features drastically reduce the number of background events arising from collisions of fast atoms with residual gas molecules and thus are essential for trace analysis applications of the technique of resonance ionization spectroscopy in collinear geometry. [ABSTRACT FROM AUTHOR]

A new excitation/detection scheme for Fourier-transform-ion-cyclotron-resonance (FT-ICR) studies is described. The ions are created in the center of a hyperbolic Penning trap and excited to a large magnetron radius. Parametric-mode excitation is used to drive the cyclotron motion. The ions are detected in the conventional dipole-mode detection scheme by use of a segmented ring electrode. Since the resonance frequencies of excitation (ν[sub +] - ν[sub -]) and detect/on (ν[sub +], the reduced cyclotron frequency) differ by the magnetron frequency (ν[sub -]), this method allows the simultaneous excitation and detection of the ion motion. [ABSTRACT FROM AUTHOR]

Laser resonance ionization has been applied to ionize radioactive atoms released from thick ISOLDE/CERN targets. Laser light from pulsed dye lasers with a high repetition rate (10 kHz) was used for stepwise excitation and ionization. By this method, efficiency as well as the selectivity of the target/ion source system could be improved. In a series of off- line and on-line studies, the resonance ionization of elements with different ionization potentials, such as Yb (E[sub i] = 6.2 eV), Tm (E[sub i] = 5.8 eV) and Sn (E[sub i] = 7.3 eV), was investigated. For Yb, photoionization efficiencies of up to 15% have been measured. An efficiency of 0.2% was obtained for Sn at the on-line separator ISOLDE-3. However, this value can be improved by about two orders of magnitude using a transition to an autoionizing state at 59 375.9 cm[sup -1]. [ABSTRACT FROM AUTHOR]

Discusses the thermionic electron emission of small tungsten cluster anions on the milliseconds time scale. Storage of the anions in a Penning trap; Electronic excitation of the cluster ions by photoabsorption; Observation of delayed electron emission on the milliseconds time scale by variation of the storage duration between laser excitation and ion detection.

Abstract: The study of nuclear electron capture (EC) offers an exciting alternative for the determination of the neutrino mass. Whereas only tritium and 187Re can be used in the case of β-decay experiments involving the anti-neutrino, a potentially large number of EC-nuclides can be used in experiments involving the monochromatic neutrino. This alternative to β-decay experiments requires an accurate measurement of -values of appropriate candidates. In the present work we initiate a search for such a candidate and determined the -value of the electron capture in 194Hg by direct mass measurements of 194Hg and 194Au. The new -value of 29(4) keV determined by the ISOLTRAP Penning-trap mass spectrometer at ISOLDE/CERN forbids the K-capture for 194Hg. However, it allows a determination of the neutrino mass by a combination of a micro-calorimetric measurement of the de-excitation spectrum from L-capture in 194Hg and a comparable -value remeasurement by high-precision Penning trap mass spectrometry. [ABSTRACT FROM AUTHOR]

At the Helmholtz center GSI, PHELIX (Petawatt High Energy Laser for heavy Ion eXperiments) has been commissioned for operation in stand-alone mode and, in combination with ions accelerated up to an energy of 13 MeV/u by the heavy ion accelerator UNILAC. The combination of PHELIX with the heavy-ion beams available at GSI enables a large variety of unique experiments. Novel research opportunities are spanning from the study of ion–matter interaction, through challenging new experiments in atomic physics, nuclear physics, and astrophysics, into the field of relativistic plasma physics. [ABSTRACT FROM AUTHOR]

The mass of an atom incorporates all its constituents and their interactions. The difference between the mass of an atom and the sum of its building blocks (the binding energy) is a manifestation of Einstein’s famous relation E = mc2. The binding energy determines the energy available for nuclear reactions and decays (and thus the creation of elements by stellar nucleosynthesis), and holds the key to the fundamental question of how heavy the elements can be. Superheavy elements have been observed in challenging production experiments, but our present knowledge of the binding energy of these nuclides is based only on the detection of their decay products. The reconstruction from extended decay chains introduces uncertainties that render the interpretation difficult. Here we report direct mass measurements of trans-uranium nuclides. Located at the farthest tip of the actinide species on the proton number–neutron number diagram, these nuclides represent the gateway to the predicted island of stability. In particular, we have determined the mass values of 252-254No (atomic number 102) with the Penning trap mass spectrometer SHIPTRAP. The uncertainties are of the order of 10 keV/c2 (representing a relative precision of 0.05 p.p.m.), despite minute production rates of less than one atom per second. Our experiments advance direct mass measurements by ten atomic numbers with no loss in accuracy, and provide reliable anchor points en route to the island of stability. [ABSTRACT FROM AUTHOR]

Penning traps are widely used for high-precision mass measurements of radionuclides related to nuclear astrophysics studies and the evolution of nuclear structure far away from stability. With the stopping of secondary beams in gas cells together with advanced ion-beam manipulation techniques their reach has been extended to rare isotopes of essentially all elements. The Penning trap mass spectrometer SHIPTRAP at GSI Darmstadt has recently demonstrated that even highprecision mass measurements of transfermium elements can be performed despite low production rates of only about one particle per second. This important milestone opens new perspectives for the study of superheavy elements with ion traps. [ABSTRACT FROM AUTHOR]

At the GSI Helmholtz-Center for Heavy-Ion Research, highly-charged ions up to bare uranium are produced by passing a 400 MeV/u beam through matter. Subsequently, the ions are decelerated, first in the experimental storage ring ESR from 400 to 4 MeV/u and in the HITRAP linear decelerator. It consists of an interdigital H-type (IH) structure and a radio-frequency quadrupole (RFQ) structure operated in inverse mode and decelerates the ions first from 4 MeV/u to 0.5 MeV/u and then to 6 keV/u. Deceleration down to 0.5 MeV/u has been demonstrated but its efficiency needs to be improved. [ABSTRACT FROM AUTHOR]

The interest to produce negative osmium ions is manifold in the realm of high-accuracy ion trap experiments: high-resolution nearly Doppler-free laser spectroscopy, antihydrogen formation in its ground state, and contributions to neutrino mass spectrometry. Production of these ions is generally accomplished by sputtering an Os sample with Cs+ ions at tens of keV. Though this is a well-established method commonly used at accelerators, these kind of sources are quite demanding and tricky to operate. Therefore, the development of a more straightforward and cost effective production scheme will be of benefit for ion trap and other experiments. Such a scheme makes use of desorption and ionization with pulsed lasers and identification of the ions by time-of-flight mass spectrometry. First investigations of negative osmium ion production using a pulsed laser for desorption and ionization and a commercial matrix-assisted laser desorption/ionization time-of-flight system for identification has demonstrated the suitability of this technique. More than 103 negative osmium ions per shot were registered after bombarding pure osmium powder with a 5 ns pulse width Nd:yttrium aluminum garnet laser. The limitation in the ion number was imposed by the detection limit of the microchannel plate detector. [ABSTRACT FROM AUTHOR]

We report on first measurements towards an Ives–Stilwell test of time dilation at velocities around 0.3c. In Ives–Stilwell type experiments, fast atomic ions containing a well-known transition are used as moving clocks, and time dilation as well as the velocity can be derived from the simultaneous laser-spectroscopic measurements of the Doppler shifts with and against the direction of motion. To accurately measure these Doppler shifts, the Doppler broadening caused by the ions velocity distribution needs to be overcome. We performed first feasibility studies for laser spectroscopy on 7Li+ ions in the 2s3S21 metastable ground state at the Gesellschaft für Schwerinonenforschung (GSI) in Darmstadt. The ions were stored in the Experimental Storage Ring (ESR) at a velocity of 0.338c, and optical–optical double-resonance spectroscopy on a closed Λ-type three level system was performed with two lasers propagating antiparallel to the ions motion. We found that Doppler shift measurements on a narrow subclass of the ions velocity distribution with sufficient signal-to-noise ratio are possible if the ion beam is electron-cooled and bunched. Together with the control of systematic error sources developed in our previous experiments on slower beams, the ESR experiment promises an improvement of previously achieved sensitivities to time dilation by about an order of magnitude. [ABSTRACT FROM AUTHOR]

Accurate atomic mass measurements of neutron-deficient and neutron-rich nuclides around the doubly-magic 208Pb and of neutron-rich cesium isotopes were performed with the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The masses of 145,147Cs, 181,183Tl, 186Tl m , 187Tl m , 196Tl m , 205Tl, 197Pb m , 208Pb, 190–197Bi, 209,215,216Bi, 203,205,229Fr, and 214,229,230Ra were determined. The obtained relative mass uncertainty in the range of 2 × 10-7 to 2 × 10-8 is not only required for safe identification of isomeric states but also allows mapping the detailed structure of the mass surface. A mass adjustment procedure was carried out and the results included into the Atomic Mass Evaluation. The resulting separation energies are discussed and the mass spectrometric and laser spectroscopic data are examined for possible correlations. [Copyright &y& Elsevier]

Frequency ratio measurements with different combinations of the singly charged ions from 21, 22, 23Na , 22, 24Mg , and 37, 39K were performed at the on-line Penning trap mass spectrometer ISOLTRAP, CERN, Geneva. The masses and mass differences were deduced with a relative uncertainty of about or even below one part in 108 for the ions of interest using a least-squares analysis of all measured relations. The results have direct consequences for weak-interaction study as they give additional input to the test of CVC, and for nuclear astrophysics, because they help to establish the minimum observable signal for a NeNa cycle in a nova burst. We report here about the measurements and the detailed evaluation. [ABSTRACT FROM AUTHOR]

ISOLTRAP is a Penning trap mass spectrometer for high-precision mass measurements on short-lived nuclides installed at the on-line isotope separator ISOLDE at CERN. The masses of close to 300 radionuclides have been determined up to now. The applicability of Penning trap mass spectrometry to mass measurements of exotic nuclei has been extended considerably at ISOLTRAP by improving and developing this double Penning trap mass spectrometer over the past two decades. The accurate determination of nuclear binding energies far from stability includes nuclei that are produced at rates less than 100 ions/s and with half-lives well below 100ms. The mass-resolving power reaches 107 corresponding to 10keV for medium heavy nuclei and the uncertainty of the resulting mass values has been pushed down to below 10-8. The article describes technical developments achieved since 1996 and the present performance of ISOLTRAP. [ABSTRACT FROM AUTHOR]

The Penning-trap mass spectrometer SHIPTRAP allows precision mass measurements of rare isotopes produced in fusion-evaporation reactions. In the first period of operation the masses of more than 50 neutron-deficient radionuclides have been measured. In this paper the perspectives for direct mass measurements of rare isotopes around nobelium are discussed and the achievable precision is addressed. The temporal stability of the magnetic field, an important issue for the long measurement times resulting from the low production rates, was investigated and the time-dependent uncertainty due to magnetic field fluctuations was determined. Based on the present performance direct mass measurements of nobelium isotopes are already feasible. With several technical improvements heavier elements between Z=102–105 will be in reach. [ABSTRACT FROM AUTHOR]

Direct mass measurements of nuclides near to the supposed end-point region of the astrophysical rp-process were performed at SHIPTRAP, the Penning trap mass spectrometer at GSI Darmstadt. The masses of 24 nuclides were measured with relative uncertainties between 5 . 10-8 and 2 . 10-7 . Three of them, 107Sb , 111I and 112I , were determined experimentally for the first time. The data analysis and mass evaluation are presented in detail. [ABSTRACT FROM AUTHOR]

Abstract: The extraction efficiency and extraction time of the SHIPTRAP gas-filled stopping cell were measured and chemical processes occurring during extraction of the stopped ions were investigated. The measurements were performed using 219Rn recoil ions from the α-decay of a calibrated point-like 223Ra ion source. The extraction time was measured to be shorter than 10ms at a helium gas pressure in the gas cell of 40mbar. Thus, nuclides with half-lives on the order of a few milliseconds are accessible for the various precision experiments planned at SHIPTRAP. Extraction efficiencies of up to 30% were obtained at a helium pressure of 50mbar. The estimated total efficiency of the gas cell, derived from the product of calculated stopping and measured extraction efficiency, amounts to about 10%. Factors limiting the efficiency are quantitatively understood. Under standard operating conditions, ion–molecule reactions in the gas cell do not seem to limit the efficiency of the gas cell significantly. [Copyright &y& Elsevier]

Abstract: The response of ions stored in a Penning trap to excitation by an octupolar radio frequency field was investigated using the time-of-flight ion-cyclotron resonance method at the SHIPTRAP Penning trap mass spectrometer at GSI. The mass resolving power can be improved at least by an order of magnitude and the accuracy more than doubled as compared to the conventional quadrupolar excitation. It has been shown that the octupolar excitation can be used to determine the mean magnetron radius of the stored ions as well as the radius of their initial spatial distribution in the Penning trap. Along with the experimental investigation, the octupolar excitation in a cylindrical Penning trap was simulated. Excellent agreement between experiment and simulation is observed. [Copyright &y& Elsevier]

A decelerator will be installed at GSI in order to provide and study heavy nuclei without or with only few electrons at very low energies or even at rest. Highly-charged ions will be produced by stripping at relativistic energies. After electron cooling and deceleration in the Experimental Storage Ring (ESR) the ions are ejected out of the storage ring at 4 MeV/u and further decelerated in a combination of linear accelerator structures operated in reverse. Finally, they are injected into a Penning trap where the ions are cooled to 4 K by electron cooling in combination with resistive cooling. From here, the ions can be transferred in a quasi DC or in a pulsed mode to different experimental setups. This article describes the technical concepts of this project focused on the Penning trap. [ABSTRACT FROM AUTHOR]

The Penning-trap mass spectrometer SHIPTRAP was designed for precision mass measurements of radionuclides produced in fusion–evaporation reactions. The latest measurement campaign covered heavy nuclei ( A>90) related to the astrophysical rapid proton capture process. The masses of 34 neutron-deficient radionuclides have been measured since February 2006 with relative uncertainties between 5×10−8 and 1×10−7. Furthermore, the use of an octupolar RF excitation for the time-of-flight ion-cyclotron-resonance technique was investigated and an increase of the resolving power by a factor of ten was observed in agreement with simulations. This will allow to resolve isomeric states with excitation energies of a few 10 keV only. [ABSTRACT FROM AUTHOR]

The Doppler-free laser-spectroscopic frequency measurement of Doppler-shifted optical lines in forward and backward direction of a fast ion beam permits a sensitive test of the relativistic Doppler-formula and, hence, the relativistic time dilation factor $$ \gamma _{{SR}} = {\left( {1 - {\nu ^{2} } \mathord{\left/ {\vphantom {{\nu ^{2} } {c^{2} }}} \right. } {c^{2} }} \right)}^{{{ - 1} \mathord{\left/ {\vphantom {{ - 1} 2}} \right. } 2}} $$ . An experiment on metastable 7Li+, stored at a velocity of v = 0.064 c in the Heidelberg heavy-ion storage ring TSR, has confirmed time dilation with unprecedented accuracy. Latest tests at two different ion-velocities ( v = 0.03 c and v = 0.064 c) will enhance these measurements. An improved version of this experiment will be carried out at the experimental storage ring (ESR) at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt. The ESR permits 7Li+ to be stored at v = 0.33 c which promises an improvement of the sensitivity to deviations from γ SR by an order of magnitude. A first test at the ESR has shown the feasibility for this kind of experiment. [ABSTRACT FROM AUTHOR]

We propose determination of isotope shifts for radioactive beryllium isotopes using laser cooled ions in a linear radio frequency (RF) trap. Based on these measurements, combined with precise mass shift calculations, it will be possible to extract model-independent nuclear charge radii of 7,9,10Be and the one-neutron halo 11Be with precision better than 3%. Radioactive beryllium isotopes produced at ISOLDE and ionized with a laser ion source will be cooled and bunched in the radio frequency quadrupole buncher of ISOLTRAP. Ion temperatures will be reduced to the mK range by sympathetic cooling with co-trapped laser cooled ions in a specially designed two-stage linear RF trap. Resonances will be detected via fluorescence and frequencies measured with a femtosecond frequency comb. [ABSTRACT FROM AUTHOR]

Abstract: The masses of 72–78,80,82,86Kr were measured directly with the ISOLTRAP Penning trap mass spectrometer at ISOLDE/CERN. For all these nuclides, the measurements yielded mass uncertainties below 10 keV. The ISOLTRAP mass values for 72–75Kr outweighed previous results obtained by means of other techniques, and thus completely determine the new values in the Atomic-Mass Evaluation. Besides the interest of these masses for nuclear astrophysics, nuclear structure studies, and Standard Model tests, these results constitute a valuable and accurate input to improve mass models. In this paper, we present the mass measurements and discuss the mass evaluation for these Kr isotopes. [Copyright &y& Elsevier]

Abstract: A system of two crystal spectrometers for accurate wavelength measurements of hard X-rays emitted by heavy ions in flight is presently being completed. The configuration is working in the focusing compensated asymmetric laue (FOCAL) mode along with high performance two-dimensional position sensitive micro-strip Ge detectors. Recent tests of the spectrometer have been performed securing quantitatively spectral resolving power and efficiency predicted by numerical simulations. For the proposed application, nearly perfect Silicon single crystals need to be bent cylindrically using a precision crystal-bending device, close to the limit where they start to break. [Copyright &y& Elsevier]

Abstract: An ion-catcher device consisting of a buffer-gas stopping cell and a radio-frequency quadrupole (RFQ) has been built for the SHIPTRAP facility at GSI. Results of characterisation measurements with the buffer-gas cell and the extraction RFQ performed at GSI in Darmstadt and at the MLL (Maier-Leibnitz-Laboratory) in Garching are presented. The set-up was tested off-line using laser-produced ions and on-line using stable beams and fusion–evaporation products. During the on-line measurements the ions with total energies of around 200keV/u were thermalised in helium buffer gas at 40–60mbar. In the following they were guided by a combination of electric RF- and DC-fields until they were transported by the gas flow through the extraction nozzle. After being extracted by a supersonic gas jet the ions were separated from the buffer gas and guided by the extraction RFQ towards subsequent detection systems. Depending on the electric-field strength average extraction times of around 10ms and an overall efficiency (including stopping and extraction) between 4% and 8% have been achieved. [Copyright &y& Elsevier]

The atomic masses of 76,77,80,81,86,88Sr and 124,129,130,131,132Sn were measured by means of the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. 76Sr is now the heaviest N=Z nucleus for which the mass is measured to a precision better than 35 keV. For the tin isotopes in the close vicinity of the doubly magic nucleus 132Sn, mass uncertainties below 20 keV were achieved. An atomic mass evaluation was carried out taking other experimental mass values into account by performing a least-squares adjustment. Some discrepancies between older experimental values and the ones reported here emerged and were resolved. The results of the new adjustment and their impact will be presented. [Copyright &y& Elsevier]

Abstract: We present a short overview of the current status of the new accelerator project FAIR at GSI with the new double synchrotron rings and the multi-storage rings. The key features of the new facility, which provides intense relativistic beams of stable and unstable nuclei, are introduced and their relation to the anticipated experimental programs in nuclear structure physics and antiproton physics is shown. The main emphasis in this overview is given to the atomic physics program with unique opportunities which will be provided e.g. by bare U92+ ions with kinetic energies continuously variable between relativistic energies corresponding to γ up to ≅35 down to kinetic energies of such ions in traps corresponding to fractions of a Kelvin. [Copyright &y& Elsevier]

Abstract: We report on high-accuracy mass measurements and isomer identification of 187Pb. In this nuclide, two close-lying isomeric states are known from α-decay studies. With the combined use of the ISOLDE resonance ionization laser ion source and the Penning trap mass spectrometer ISOLTRAP the energy difference of 187Pb and 187m Pb was determined to be . This is the lowest isomeric excitation energy ever determined by weighing nuclei. [Copyright &y& Elsevier]

The Penning trap mass spectrometer ISOLTRAP has to date been used for the determination of close to 300 masses of radionuclides. A relative mass uncertainty of 10-8 can now be reached. Recent highlights were measurements of rp-process nuclides as for instance 72-74Kr or superallowed β emitters like 22Mg, 74Rb and 34Ar. The heaviest nuclides measured so far with ISOLTRAP are neutron-rich radium and francium isotopes. An overview of ISOLTRAP mass measurements and details about the recent experiment on 229-232Ra and 230Fr are presented. [ABSTRACT FROM AUTHOR]

Abstract: Measurements of the anomalous magnetic moment of the electron bound in hydrogen-like ions with spinless nuclei have proven to be highly sensitive tests of corresponding calculations based on bound-state quantum electrodynamics. Measurements performed on H-like carbon 12C5+ and oxygen 16O7+ together with bound-state QED calculations on the same level of accuracy have achieved sensitivities around 0.25% of the QED bound state contributions to the calculated electronic g-factors of these ions. Currently, a similar experiment on hydrogen-like calcium 40Ca19+, lithium-like calcium 40Ca17+ and other medium-heavy ions is being prepared, which is capable of increasing this sensitivity on the experimental side by more than one order of magnitude. To that end, several novel experimental techniques have been developed. In the following, we will give a motivation for such a measurement, present the experimental requirements and technique and discuss the possible benefits. [Copyright &y& Elsevier]

Abstract: Masses of 582 neutron-deficient nuclides were measured with time-resolved Schottky mass spectrometry at the FRS-ESR facility at GSI, 117 were used for calibration. The masses of 71 nuclides were obtained for the first time. A typical mass accuracy of 30 μu was achieved. These data have entered the latest atomic mass evaluation. The mass determination of about 140 additional nuclides was possible via known energies (Q-values) of α-, β-, or proton decays. The obtained results are compared with the results of other measurements. [Copyright &y& Elsevier]