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Publikationen von
PD Dr. Wolfgang Quint

Alle Publikationen des HI Jena

2022

S. Ringleb, M. Kiffer, N. Stallkamp, S. Kumar, J. Hofbrucker, B. Reich, B. Arndt, G. Brenner, M. Ruiz-Lopéz, S. Düsterer, M. Vogel, K. Tiedtke, W. Quint, T. Stöhlker, and G. G. Paulus
High-intensity laser experiments with highly charged ions in a Penning trap
Physica Scripta 97, 084002 (2022)

Abstract: We have conceived and built the HILITE (High-Intensity Laser-Ion Trap Experiment) Penning-trap setup for the production, confinement and preparation of pure ensembles of highly charged ions in a defined quantum state as a target for various high-intensity lasers. This enables a broad suite of laser-ion interaction studies at high photon energies and/or intensities, such as non-linear photo-ionisation studies. The setup has now been used to perform experiments at one such laser facility, namely the FLASH Free-Electron Laser at DESY in Hamburg, Germany. We describe the experimental possibilities of the apparatus, the results of the first measurements and future experiments at other laser facilities.

2020

M. Kiffer, S. Ringleb, N. Stallkamp, S. Kumar, B. Arndt, M. Vogel, W. Quint, and T. Stöhlker
Characterisation of ion bunches by a single-pass non-destructive charge counter
Journal of Physics: Conference Series 1412, 242004 (2020)

Abstract: Synopsis We present non-destructive single-pass ion bunch detection and characterisation by measuring the induced image charge in a detection electrode. The presented technique allows direct determination of ion kinetic energy, absolute ion number and spatial ion bunch length. We will show the results of corresponding measurements with bunches of low-energy highly charged ions and discuss the minimum detectable number of charges.

N. Stallkamp, S. Ringleb, B. Arndt, M. Kiffer, S. Kumar, G. Paulus, W. Quint, T. Stöhlker, and M. Vogel
HILITE-A well-defined ion target for laser experiments
Journal of Physics: Conference Series 1412, 092009 (2020)

Abstract: We present a Penning-trap-based setup for the study of light-matter interactions in the high-power and/or high-intensity laser regime, such as multi-photon ionization and field ionization. The setup applies ioncloud formation techniques to highly charged ions to the end of specific target preparation, as well as nondestructive detection techniques to identify and quantify the interaction educts and products.

N. Stallkamp, S. Ringleb, B. Arndt, M. Kiffer, S. Kumar, T. Morgenroth, G. G. Paulus, W. Quint, Th. Stöhlker, and M. Vogel
HILITE—A tool to investigate interactions of matter and light
X-Ray Spectrometry 49, 188 (2020)

Abstract: Detailed investigations of laser–ion interactions require well‐defined ion targets and detection techniques for high‐sensitivity measurements of reaction educts and products. To this end, we have designed and built the High‐Intensity Laser‐Ion Trap Experiment Penning trap setup, which features various ion‐target preparation techniques including selection, cooling, compression, and positioning as well as destructive and non‐destructive measurement techniques to determine the number of stored ions for all charge states individually and simultaneously. We have recently performed first commissioning experiments of ion deceleration and dynamic ion capture with highly charged ion bunches from an electron beam ion source. We have characterized our single‐pass non‐destructive ion counter in detail and were able to determine the ion velocity as well as the number of ions from the signals acquired.

2019

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
g Factor of Lithiumlike Silicon: New Challenge to Bound-State QED
Physical Review Letters 123, 173001 (2019)

Abstract: The recently established agreement between experiment and theory for the g factors of lithiumlike silicon and calcium ions manifests the most stringent test of the many-electron bound-state quantum electrodynamics (QED) effects in the presence of a magnetic field. In this Letter, we present a significant simultaneous improvement of both theoretical gth=2.000 889 894 4 (34) and experimental gexp=2.000 889 888 45 (14) values of the g factor of lithiumlike silicon 28Si11+. The theoretical precision now is limited by the many-electron two-loop contributions of the bound-state QED. The experimental value is accurate enough to test these contributions on a few percent level.

S. Kumar, W. Quint, S. Ringleb, C. P. Safvan, N. Stallkamp, T. Stöhlker, and M. Vogel
Properties of a cylindrical Penning trap with conical endcap openings
Physica Scripta 94, 075401 (2019)

Abstract: We describe the results of analytical calculations and numerical simulations of the confinement properties of a mechanically compensated cylindrical Penning trap which has conical endcap openings for large-solid-angle access for example with highly focused laser beams. While the analytical calculations show that under the common geometrical conditions the harmonicity of the confining fields near the centre of the trap does not change when a conical shape of the endcap electrodes is introduced, numerical simulations show significant changes when the opening angle of the cone exceeds a certain critical angle. We also show that these sharp features are due to the fringe-field effects above the critical angle, which are not described by the analytical calculations. These effects are also observed in a cylindrical Penning trap when the length of the endcap electrodes is reduced below a certain critical value.

2017

M. Wiesel, G. Birkl, M. S. Ebrahimi, A. Martin, W. Quint, N. Stallkamp, and M. Vogel
Optically transparent solid electrodes for precision Penning traps
Review of Scientific Instruments 88, 123101 (2017)

Abstract: We have conceived, built, and operated a cryogenic Penning trap with an electrically conducting yet optically transparent solid electrode. The trap, dedicated to spectroscopy and imaging of confined particles under large solid angles, is of “half-open” design with one open endcap and one closed endcap that mainly consists of a glass window coated with a highly transparent conductive layer. This arrangement allows for the trapping of externally or internally produced particles and yields flexible access for optical excitation and efficient light collection from the trapping region. At the same time, it is electrically closed and ensures long-term ion confinement under well-defined conditions. With its superior surface quality and its high as well as homogeneous optical transmission, the window electrode is an excellent replacement for partially transmissive electrodes that use holes, slits, metallic meshes, and the like.

2016

M. S. Ebrahimi, N. Stallkamp, W. Quint, M. Wiesel, M. Vogel, A. Martin, and G. Birkl
Superconducting radio-frequency resonator in magnetic fields up to 6 T
Review of Scientific Instruments 87, 075110 (2016)

Abstract: We have measured the characteristics of a superconducting radio-frequency resonator in an external magnetic field. The magnetic field strength has been varied with 10 mT resolution between zero and 6 T. The resonance frequency and the quality factor of the resonator have been found to change significantly as a function of the magnetic field strength. Both parameters show a hysteresis effect which is more pronounced for the resonance frequency. Quantitative knowledge of such behaviour is particularly important when experiments require specific values of resonance frequency and quality factor or when the magnetic field is changed while the resonator is in the superconducting state.

2015

S. Ringleb, M. Vogel, S. Kumar, W. Quint, G. G. Paulus, and Th. Stöhlker
HILITE—ions in intense photon fields
Physica Scripta 2015, 014067 (2015)

Abstract: We are currently devising the open-endcap Penning trap experiment (high-intensity laser ion-trap experiment) as a tool for ion confinement, manipulation and detection to be used at high-energy and/or high-intensity laser facilities. This instrument will allow studies of laser–ion interactions with well-defined ion targets, and to detect the reaction products non-destructively. The ion target may be controlled concerning the constituent species, the density, shape and position with respect to the laser focus. For commissioning experiments, we optimize the focusing parameters to achieve a high number of ionized particles per shot. The detection electronics is designed to measure all charge states of all nuclei up to xenon. We plan first experiments with argon and xenon irradiated by a titanium:sapphire chirped-pulse-amplification laser system with 10 mJ pulse energy and a pulse duration of 30 fs.

M. Vogel, G. Birkl, M. Ebrahimi, D. von Lindenfels, A. Martin, G. Paulus, W. Quint, S. Ringleb, Th. Stöhlker, and M. Wiesel
Extreme-field physics in Penning traps
Hyperfine Interactions 236, 65 (2015)

Abstract: We present two Penning trap experiments concerned with different aspects of the physics of extreme electromagnetic fields, the ARTEMIS experiment designed for bound-electron magnetic moment measurements in the presence of the extremely strong fields close to the nucleus of highly charged ions, and the HILITE experiment, in which well-defined ion targets are to be subjected to high-intensity laser fields.

2014

D. Tiedemann, K. E. Stiebing, D. F. A. Winters, W. Quint, V. Varentsov, A. Warczak, A. Malarz, and Th. Stöhlker
A pulsed supersonic gas jet target for precision spectroscopy at the HITRAP facility at GSI
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 764, 387 (2014)

Abstract: A pulsed supersonic gas jet target for experiments at the HITRAP facility at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt has been designed and built as a multi-purpose installation for key experiments on fundamental atomic physics in strong fields. This setup is currently installed at the Institut für Kernphysik of Goethe-University, Frankfurt am Main (IKF), in order to explore its operation prior to its installation at the HITRAP facility. Design and performance of the target are described. The measured target densities of 5.9×10^12 atoms/cm3 for helium and 8.1×10^12 atoms/cm³ for argon at the stagnation pressure of 30 bar match the required values. The target-beam diameter of 0.9 mm and the pulsed operation mode (jet built-up-time ≤15 ms) are well suited for the use at HITRAP.

2012

M. Vogel, W. Quint, G.G. Paulus, and Th. Stöhlker
A Penning trap for advanced studies with particles in extreme laser fields
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 285, 65 (2012)

Abstract: We present a Penning trap as a tool for advanced studies of particles in extreme laser fields. Particularly, trap-specific manipulation techniques allow control over the confined particles’ localization and spatial density by use of trap electrodes as ‘electrostatic tweezers’ and by application of a ‘rotating wall’, respectively. It is thereby possible to select and prepare well-defined ion ensembles and to optimize the laser–particle interaction. Non-destructive detection of reaction educts and products with up to single-ion sensitivity supports advanced studies by maintaining the products for further studies at extended confinement times of minutes and above. The trap features endcaps with conical openings for applications with strongly focused lasers. We show that such a modification of a cylindrical trap is possible while harmonicity and tunability are maintained.

2011

Th. Stöhlker, H. F. Beyer, A. Bräuning-Demian, C. Brandau, A. Gumberidze, R. E. Grisenti, S. Hagmann, F. Herfurth, Ch. Kozhuharov, Th. Kühl, D. Liesen, Yu. Litvinov, R. Märtin, W. Nörtershäuser, O. Kester, N. Petridis, W. Quint, U. Schramm, R. Schuch, U. Spillmann, S. Trotsenko, and G. Weber
SPARC: The Stored Particle Atomic Research Collaboration At FAIR
AIP Conference Proceedings 1336, 132 (2011)

Abstract: The future international accelerator Facility for Antiproton and Ion Research (FAIR) encompasses 4 scientific pillars containing at this time 14 approved technical proposals worked out by more than 2000 scientists from all over the world. They offer a wide range of new and challenging opportunities for atomic physics research in the realm of highly‐charged heavy ions and exotic nuclei. As one of the backbones of the Atomic, Plasma Physics and Applications (APPA) pillar, the Stored Particle Atomic Physics Research Collaboration (SPARC) has organized tasks and activities in various working groups for which we will present a concise survey on their current status.

2010

D. Rodríguez, K. Blaum, W. Nörtershäuser, M. Ahammed, A. Algora, G. Audi, J. Äystö, D. Beck, M. Bender, J. Billowes, M. Block, C. Böhm, G. Bollen, M. Brodeur, T. Brunner, B. Bushaw, R. Cakirli, P. Campbell, D. Cano-Ott, G. Cortés, J. Crespo López-Urrutia, P. Das, A. Dax, A. De, P. Delheij, T. Dickel, J. Dilling, K. Eberhardt, S. Eliseev, S. Ettenauer, K. Flanagan, R. Ferrer, J.-E. García-Ramos, E. Gartzke, H. Geissel, S. George, C. Geppert, M. Gómez-Hornillos, Y. Gusev, D. Habs, P.-H. Heenen, S. Heinz, F. Herfurth, A. Herlert, M. Hobein, G. Huber, M. Huyse, C. Jesch, A. Jokinen, O. Kester, J. Ketelaer, V. Kolhinen, I. Koudriavtsev, M. Kowalska, J. Krämer, S. Kreim, A. Krieger, T. Kühl, A. Lallena, A. Lapierre, F. Le Blanc, Y. Litvinov, D. Lunney, T. Martínez, G. Marx, M. Matos, E. Minaya-Ramirez, I. Moore, S. Nagy, S. Naimi, D. Neidherr, D. Nesterenko, G. Neyens, Y. Novikov, M. Petrick, W. Plaß, A. Popov, W. Quint, A. Ray, P.-G. Reinhard, J. Repp, C. Roux, B. Rubio, R. Sánchez, B. Schabinger, C. Scheidenberger, D. Schneider, R. Schuch, S. Schwarz, L. Schweikhard, M. Seliverstov, A. Solders, M. Suhonen, J. Szerypo, J. Taín, P. Thirolf, J. Ullrich, P. Duppen, A. Vasiliev, G. Vorobjev, C. Weber, K. Wendt, M. Winkler, D. Yordanov, and F. Ziegler
MATS and LaSpec: High-precision experiments using ion traps and lasers at FAIR
The European Physical Journal Special Topics 183, 1 (2010)

Abstract: 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 β-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.