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A laser ablation ion source has been built and tested at the COALA beamline. Time-of-flight measurements for various elements are sufficiently accurate to confirm the production of the intended ion species. Furthermore, the isotope shift between 40Ca+ and 44Ca+ has been determined on these bunched beams by collinear laser spectroscopy and compared to previous measurements. The frequency of the $4s{}{}^{2}\textit {S}_{1/2} \rightarrow 4p{}{}^{2}\textit {P}_{1/2}$ 4 s 2 S 1 / 2 → 4 p 2 P 1 / 2 transition has been determined to $\nu ^{\mathrm {D1}}_{0}=755 222 766.8(15)$ ν 0 D 1 = 755222766.8 ( 15 ) MHz for 40Ca+, as well as the corresponding isotope shift of 44Ca+ to 848.1(23) MHz. This is in a good agreement to more accurate measurements performed in a recent ion trap experiment and demonstrates the strength of the collinear-anticollinear approach to reduce systematic effects caused by the broad velocity distribution generated in the ablation process.

The room-temperature electrostatic heavy ion storage ring FLSR was originally designed to study the collision dynamics of atoms and molecules. Recently it has been equipped with a RF plasma ion source combined with a charge exchange cell to be able to perform studies with negative ions in the ring. In preliminary experiments beams of He−, O− and OH− could successfully be stored. The measured lifetime of the metastable He−–ion is in good agreement with previous results, showing that the lifetime measurement in this case is not limited by the storage time due to collisional detachment. In the case of O− and OH− storage times in the order of seconds have been achieved. In a next step laser beams will be introduced in the ring allowing photodetachment studies of vibrationally cold molecules.

Laser ablation opens a material-independent method to produce ions from transition metals for laser spectroscopy. To overcome some drawbacks of this process, an ion source is under development at TU Darmstadt. A distinctive feature of this source is that ions are produced via laser ablation in presence of helium buffer gas where they stop and cool in the process of their collisions with the buffer gas atoms and are then extracted by the gas flow into low-pressure conditions through the supersonic nozzle. The compact RF-only funnel ion guide placed on the axis behind the nozzle exit allows for effective extraction of high-quality ion beams into a pressure region below 10− 4 mbar. The extraction is realized by using the gas flow trough a supersonic nozzle and an RF-only funnel ion guide, followed by a second nozzle and an RF+DC funnel representing two differential pumping stages. The technical details of this laser ablation ion source are described and the results of the first tests with the RF-only funnel are presented.

This work presents the results of BiFeO3 and Bi0.9Eu0.1FeO3 multiferroic materials, synthesized via a simple solid-phase reaction method. Both of the synthesized materials were in the rhombohedral R3c structure as observed by X-ray diffraction (XRD). The presence of a doublet along with a sextet in Mossbauer spectra indicates an impurity phase (Bi2Fe4O9). The presence of Fe2+ ions are confirmed from Mossbauer spectroscopy study in the Bi0.9Eu0.1FeO3 sample. And the Bi0.9Eu0.1FeO3 exhibited a slight lattice distortion, observable from the results of XRD and Mossbauer spectra. We can conclude that growing of crystal homogeneity of Bi0.9Eu0.1FeO3 is better than BiFeO3.

High-precision mass measurements of short-lived ions have been traditionally performed using the Time-of-Flight Ion-Cyclotron-Resonance technique (ToF-ICR) with Singly Charged Ions (SCI) in Penning traps. In order to reach higher precision, TITAN is currently using the ToF-ICR technique with Highly Charged Ions (HCI) [1], taking advantage of the fact that the uncertainty of the mass is proportional to the factor 1/q, where q is the charge state of the ion. Meanwhile, a different technique, the so-called Phase-Imaging Ion-Cyclotron-Resonance (PI-ICR), which has been applied in other facilities with SCI, has been proven to offer a gain in resolving power and precision compared to the ToF-ICR technique [2–4]. In an effort to reach new levels of precision in the mass measurements of short-lived species at TITAN, we investigated the scenario of performing mass measurements of HCI using the PI-ICR technique. Simulations showed that as the charge state of the ions increases, the image of the ion motion in the trap appears more and more magnified on the detector. This results in an increase in the resolution of the mass measurement up to an order of magnitude.

Resonance ionization mass spectrometry is an ultra-sensitive and highly element selective tool for spectroscopy, ionization and detection of atoms and thus enables rare isotope determination. In combination with spatially resolved sputtering of neutrals by an initial ion beam, e.g. within a commercial secondary ion mass spectrometer, an isotope and isobar selective analysis technique with resolution on the micrometer scale for particles and surfaces is realized. Detection of minuscule amounts of specific actinides, e.g. of plutonium, in environmental and technical samples by this ultra-trace analysis technique requires detailed knowledge about the atomic physics of the element. Identification and characterization of the specific resonance ionization scheme applied within the particular geometry of the apparatus in use is needed. An analysis of the dependence of the specifications, specifically regarding the influence of the relative laser beam polarizations is presented here as an aspect, that could have a severe impact on isotope ratio precision and overall efficiency in the resulting ion signal.

Comparison of the Mossbauer spectra of the as-prepared native iron oxide nanoparticles (IONs) and the citrate-functionalized IONs demonstrates differences in the spectral shapes at room temperature and variations of the 57Fe hyperfine parameters at 80 K. The observed differences are claimed to result from capping the IONs with citrate, thus decreasing the particle-particle interaction while promoting interaction of the outer atomic layers of the IONs with the surface molecular coating.

To investigate the interactions of 57Fe atoms with sulfur hexafluoride SF6 molecules, in-beam Mossbauer spectra were measured for 57Mn implanted SF6 at 9 K and 65 K. Isolated 57Fe atoms or ions produced by β-decay were not trapped within the SF6 matrix. At 9 K, monomeric FeF2 and FeF3 molecules were produced by reaction of 57Fe with F atoms released by decomposition of the SF6 molecules. When the temperature of the SF6 solid was increased to 65 K, FeF4 was formed in addition to FeF2 and FeF3. Density functional calculations were performed to confirm the assignments of the candidate species identified in the Mossbauer spectra.

In the search of efficient laser resonance ionization schemes and optimal source parameters, offline laser ion source development is of importance for successful online radioactive beam delivery. An overview and update on recent TRIUMF’s resonance ionization laser ion sources (TRILIS) offline developments is presented. This includes titanium-sapphire (Ti:Sa) laser development and the investigation of the laser ionization efficiency dependence on source temperature and laser polarization.

Spinel cobalt-nickel ferrite nanoparticles, having a particle size of around 40 nm, were produced by undergoing a succession of synthesis routes comprised of chemical co-precipitation, hydrothermal treatment (HT), and etching in hydrochloric acid (ET) of concentration 2.0 mol/L. The room temperature high-field Mossbauer spectra were analyzed in detail and significant spin canting associated with Fe3+ ions at both A- and B-sites were observed for both the HT and ET samples in the presence of external magnetic field of 5 T. The effect of etching on various Mossbauer parameters such as the hyperfine field distribution, isomer shift, quadrupole splitting and the linewidth was noted. The A site and B site canting angles of the HT sample were respectively 17° and 22°, while canting angle of approximately 13° was observed for both A and B sites in the ET sample.

Fe doped FTO powders were prepared by a chemical precipitation method. Mossbauer spectra of FTO with several concentrations of Fe dopants were decomposed into two doublets (D1 and D2). A doublet with a small electric field gradient (D1) is assigned to Fe3+ in a small distorted site of the rutile structure, and another doublet (D2) to Fe3+ in a large distorted site due to F− ion and oxygen defect. Furthermore, with increase of the annealing temperature the isomer shifts tended to decrease. It suggests that Fe3+ bonds are more covalently bonded than ionic at the higher annealing temperatures. The surface layer of grains were also characterized by 57Fe CEMS. The defect structures of Fe doped FTO were estimated using the oxygen defect models of tin oxide [Mudarra Navarro et al., J. Phys. Chem. C, 119, 5596 (2015)].

A Mossbauer spectroscopic characterization of Mycobacterium tuberculosis ferredoxin (Mt Fdx) CNL73887.1 has been performed. In the Mossbauer spectrum obtained at T = 77 K two components in a 1:2 ratio are present: The minority component 1 possesses δ1 = 0.27 (± 0.02) mms−1 and ΔEQ1 = −0.53 (± 0.03) mms−1. The majority component 2 shows δ2 = 0.44 (± 0.02) mms−1 and ΔEQ2 = 1.47 (± 0.03) mms−1. This parameter set is characteristic for one Fe3+ ion and two Fe2.5+ ions present in a [3Fe-4S]0-cluster. In external magnetic fields of B = 100 mT and B = 5 T Mt Fdx shows a paramagnetic behaviour. Analysis of the field dependent spectra by means of the spin Hamilton formalism, assuming a total spin of S = 2, clearly shows that Mt Fdx contains a paramagnetic [3Fe-4S]0-cluster. The experimental results are compared to density functional theory calculations based on a crystal structure of a Rhodopseudomonas palustris (Rp) HaA2 Fdx (pdb: 4OV1) embedded in a box of water. The addition of explicit solvent molecules showed significant improvement of the accordance of calculated and experimentally obtained hyperfine parameters compared to the calculation in vacuum.

We constructed the SCRIT (Self-Confining Radioactive Ion Target) electron scattering facility to realize electron scattering off short-lived unstable nuclei at RIKEN in Japan. Electron scattering is one of the most powerful and reliable tools to study structures of atomic nuclei. However, it has been extremely difficult to apply electron scattering to unstable nuclei because of target preparation problems. SCRIT is a novel ion-trapping technique that achieves high luminosity of more than 1027 cm-?2s-?1 with a small amount of target ions. Following completion of the facility, a series of commissioning experiments of the entire facility with several stable nuclear targets, including 208Pb and 132Xe, were performed. Momentum transfer distributions of elastic scattering from those targets were successfully measured at several electron beam energies, and the charge density distribution of the 132Xe nucleus was extracted for the first time.

To achieve high-resolution selection and separation of mono-isotopic beams through projectile fragmentation or in-flight fission and to efficiently transport the secondary beams to the Rare-RI Ring (R3) for mass determination, the BigRIPS separator combined with the High-resolution Achromatic (HA) beam-line of SHARAQ is served as a two-stage separator. The first stage from F0 to F2 is used for separation of the nuclei of interest through a Bρ-ΔE-Bρ method and the second stage from F3 to S0 is employed for identification of the beam with a Bρ-ΔE-TOF method. With this scheme, all the secondary ions can be well separated on an event by event basis and be utilized for mass measurements by two complementary methods: the conventional magnetic-rigidity-time-of-flight (Bρ-TOF) method employing the BigRIPS-HA beam-line to measure exotic nuclides within 1 μ s and the newly established isochronous mass spectrometry (IMS) approach via the R3 with a measurement duration less than 1 ms. This report presents the technique advances of the BigRIPS-HA-SHARAQ-R3 as a separator/spectrometer and give a brief description of its application to the complementary TOF methods for mass measurements at RIBF.

The Time Differential Perturbed γ-γ Angular Correlation (TDPAC) measurement has been carried out with the hydrolysis product of Hafnium(Hf)-IV ion at pH1 both in bulk and under nano confinement using 181Hf/Ta as PAC probe. The experiment was performed at two different temperatures, viz., 300 K and 280 K. Three different probe sites could be identified for the bulk complex while it is four in case the complex is inside the nanopore, at both the measuring temperatures. The major site, in case of bulk complex, has a quadrupole frequency ωQ ~ 105 Mrad/s and η ~ 0.6. However, the major site, in case the complex is inside nanopore having an average pore size of 6 nm, has ωQ ~ 210 Mrad/s and η ~ 0.3. Two different values of PAC parameters corresponding to the major probe sites for the bulk and nano-confined complex, indicate completely different hydration chemistry in the present two cases.

HITRAP is a facility for deceleration of highly charged ions (HCI) produced online by the GSI accelerator. It consists of two linear stages for deceleration down to several keV/charge and an ion trap for ion cooling down to sub-eV energies. We report on two recent developments within the facility: a new design for the HITRAP cooling trap in order to improve its stability and voltage rigidity, as well as the investigation of the so-called MIVOC method in the HITRAP EBIT for production of Sb35+, Fe21+, and B5+.

A pulsed laser system has been installed at the BECOLA facility at NSCL/MSU to develop electronic population manipulation techniques for trapped ions of rare isotopes. A simulation has been developed to evaluate possible optical pumping schemes and estimate expected increase in the population of an energy level used in subsequent laser spectroscopy measurements. Development progress is on time and commissioning tests with stable Zr isotopes are planned.

Laser cooling and precision laser spectroscopy of highly charged ions are considered as frontiers of atomic physics research at heavy ion storage rings. A brief overview of the fundamentals of these powerful methods, applied to relativistic stored ion beams, is given. Preliminary results from laser cooling of lithium-like 16O5+ ion beams at a relativistic energy of 275.7 MeV/u at the heavy-ion storage ring CSRe are presented and prospects for upcoming experiments at the future facility HIAF are discussed.

The TITAN facility at TRIUMF is a series of ion traps designed for precision mass spectrometry on rare isotopes. The combination of an on-line electron beam ion trap charge breeder with a Penning trap enables measurements with radioactive ions in high charge states. The use of highly charged ions (HCI) can yield a significant gain in mass precision and mass resolving power. However, the benefits of high charge states are mitigated since the charge breeding deteriorates the beam quality. To achieve suitable beam properties and access the full potential of Penning trap mass spectrometry with HCI a cooler Penning trap (CPET) for electron cooling of highly charged radioisotopes is being developed. In this device short-lived HCI will be sympathetically cooled by a co-trapped electron plasma prior to mass measurement. For electron plasma generation electrons are injected from an off-axis electron gun placed in the fringe field of CPET’s solenoid magnet. We report on the development of an electron gun design that is adapted to the operation in lateral magnetic fields and has enabled efficient and robust electron plasma formation in CPET.

Tests of the unitarity of the Cabbibo-Kobayashi-Masakawa (CKM) matrix offer an important avenue for constraining the Standard Model of the electroweak interaction. Several methods are currently used to determine Vud, the largest element in the top-row normalization test. One such method is through the study of superallowed T = 1/2 mixed mirror transitions, which offers a complementary method to the current most-precise value that is determined from superallowed pure Fermi 0+ → 0+ transitions. The precision currently achievable by this method is currently limited by the very low number of transitions for which the Fermi-to-Gamow-Teller mixing ratio ρ has been measured. St. Benedict, the Superallowed Transition Beta-Neutrino Decay-Ion-Coincidence Trap, is currently under development at the University of Notre Dame’s Nuclear Science Laboratory, and intends to determine ρ for a range of new isotopes through measurements of the β-neutrino asymmetry parameter aβν using a linear Paul trap. In order to trap these ions, the fast, continuous secondary beam separated by the TwinSol twin solenoid separator must be thermalized and bunched. The system through which this will be done will feature a large-volume gas cell in which the ions will be thermalized, a double-RF-funnel-based ion guide system for the extraction of the ions, and a radiofrequency quadrupole (RFQ) to provide cooled ion bunches for capture in the Paul trap.

We report on the progress of an optical clock based on an indium ion (115In+) sympathetically cooled with a calcium ion (40Ca+) in a linear trap. In our previous work, we have measured the clock transition frequency with an uncertainty of 5× 10− 15, prompting an update of the Comite International des Poids et Mesures (CIPM) recommended value. The uncertainty was mainly limited by the evaluation of the Zeeman shift which was complicated by unresolved sublevel components. In contrast to the previous measurement, Zeeman sublevels are now separated by application of a magnetic field. Combined with optical pumping to specific Zeeman substates, the magnetic field application method successfully reduces the observed linewidth of the clock transition spectrum down to about 80 Hz full width at half maximum (FWHM). Frequency locking of the clock laser to the transition is demonstrated for the first time. The clock reaches a relative instability of 1.5× 10− 15 for an integration time of 4000 seconds.

The Beta-decay Paul Trap (BPT) at Argonne National Laboratory has proven to be an extremely effective tool for high-precision tests of the Standard Model via measurements of the β − ν correlation in mass-8 isotopes. Using four double-sided silicon strip detectors (DSSDs) backed by plastic scintillators and surrounding the ions confined by the BPT, the kinematics of the decays of the mirror nuclei lithium-8 and boron-8 are overdetermined when all charged decay products are measured. The most stringent low-energy limit on an intrinsic tensor current in the weak interaction was set using the BPT in 2015 (Sternberg, M.G., et al., Phys. Rev. Lett. 115, 182501 2015) utilizing trapped lithium-8. Since then, similar data for boron-8 and higher statistics data for lithium-8 have been collected and are currently being analyzed. With the elimination of radio-frequency (RF) pickup from the DSSDs and a detailed investigation of experimental systematic errors, the uncertainty is now dominated by the contribution from recoil-order terms in the decay rate. Our eventual goal is to limit tensor currents in the weak interaction with relative precision at or below 0.1%.

Nuclear structure and astrophysics studies rely heavily on precision mass measurements of rare isotopes. However, many of these isotopes far from the valley of stability can only be produced at very low rates, which are incompatible with the destructive measurement techniques used by rare isotope Penning trap mass spectrometry facilities. To this end, the Low Energy Beam and Ion Trap facility at the National Superconducting Laboratory is in the process of commissioning a single ion Penning trap (SIPT) mass spectrometer that relies on the non-destructive narrowband Fourier Transform ion cyclotron resonance technique. SIPT is the first Penning trap designed to perform mass measurements of rare isotopes produced via projectile fragmentation at rates on the order of one ion per day. The system details and cryogenic detection design, as well as results from the room and cryogenic temperature commissioning, are discussed at length.

In this work we propose a new method to form both protonium exotic $$ \mathrm{p}\overline{\mathrm{p}} $$ and lithium antiproton $$ \overline{\mathrm{p}}{\mathrm{Li}}^{+} $$ atoms by capturing the hydrogen H− and lithium Li+ ions of the LiH crystal lattice at planar or axial channeling of low-energy antiproton beams. Within sudden-perturbation approximation the probability for protons as well as for ions to be bound into different quantum levels defined by the antiproton Coulomb potential are calculated. It is shown that the probability strongly depends on the parameters of channeled antiprotons revealing various extremes (resonances): the functions of capture probabilities for all excited quantum states of antiproton are characterized by three most intense peaks. Higher probability to form heavier particles, namely antiproton lithium $$ \overline{\mathrm{p}}{\mathrm{Li}}^{+} $$, have been demonstrated.

Spin polarized particles exhibiting beta decay, such as, muon and 8Li are very useful for detecting internal magnetic fields in solids. Here, I review our attempts to use these spin polarized beams for battery materials research. Due to a unique lifetime and gyromagnetic ratio of muon, a positive muon spin rotation and relaxation (µ+SR) technique is very popular for studying microscopic internal magnetic fields in condensed matters caused by electron and nuclear magnetism. Particularly in 2009, it was found that Li+ ion diffusion in LixCoO2, which is the most common cathode material in a Li-ion battery, is detectable with µ+SR even under the presence of paramagnetic Co ions (Sugiyama et al., Phys. Rev. Lett. 103, 147601, 2009), while NMR is unable to do so due to the effect of localized magnetic moments on a spin-lattice relaxation rate. Such finding opened the door for µ+SR on energy materials research. Since then, many battery materials have been investigated with µ+SR in order to determine their intrinsic diffusion coefficient (D) of Li+ and Na+ ions. Furthermore, using such intrinsic D, the other important parameters are successfully derived, such as, the reactive surface area, diffusion pathway, and density of mobile ions. In 2018, we have initiated to measure internal magnetic fields in solids with a negative muon, i.e. a µ-SR technique, in J-PARC (Sugiyama et al., Phys. Rev. Lett. 121, 087202, 2018). This will provide a new insight for microscopic internal magnetic fields from lattice sites, while µ+SR does so from interstitial sites. On the contrary, a long lifetime of 8Li (1.21 s) makes a 8Li s-NMR technique suitable for detecting both concentration and diffusion of Li in solids. Particularly in TRIUMF, since the implantation energy of 8Li is tunable from almost 0 to about 28 keV, we can measure both spin-lattice relaxation rate and spin-spin relaxation rate as a function of depth up to about 200 nm, as well as µ+SR using a low energy muon beam in PSI. These will clarify whether the space charge layer of Li+ exists at the interface between electrode and electrolyte material.

In the development towards the Multi Ion Reflection Apparatus for Collinear Laser Spectroscopy (MIRACLS), an optical detection region for the observation of fluorescent light is added to an electrostatic ion beam trap (EIBT). In addition to its use for highly sensitive collinear laser spectroscopy, this fluorescence detection is introduced as a diagnostics tool for the study of the ion dynamics inside an EIBT. First measurements of collision-induced fluorescence in an EIBT demonstrate the technique’s diagnostics power by tracking the evolution of an ion bunch’s temporal width over its storage time inside the ion trap. Thereby, the time-focus point of the ion bunch can be determined and the influence of space-charge effects in the EIBT can be investigated. Good qualitative agreement is obtained between the measured trend of temporal widths and the simulations of the ions’ trajectories in the trap. Particularly, the observation of self-bunching on the ion-bunch structure for many simultaneously stored ions is reproduced.

For nearly four decades Collinear Laser Spectroscopy (CLS) has been employed to determine ground-state properties of short-lived radionuclides. To extend its reach to the most exotic radionuclides with very low production yields, the novel Multi Ion Reflection Apparatus for CLS (MIRACLS) is currently under development at ISOLDE/CERN. In this setup, 30-keV ion bunches will be trapped between two electrostatic mirrors of a multi-reflection time-of-flight (MR-ToF) device such that the laser beam will probe the ions during each revolution. Thus, the observation time will be extended and the experimental sensitivity will be increased significantly while maintaining the high resolution of conventional CLS. A proof-of-principle experiment is currently being performed to demonstrate the potential of CLS within a low-energy MR-ToF device. Its first experimental results benchmark the validity of ion-optical simulations from the CLS perspective, which will also be applied to MIRACLS’ 30-keV apparatus.

The present status of tests of QED with highly charged ions is reviewed. The theoretical predictions for the Lamb shift and the transition energies are compared with available experimental data. Recent achievements in studies of the hyperfine splitting and the $g$-factor isotope shift with highly charged ions are reported. Special attention is paid to tests of QED within and beyond the Furry picture at strong-coupling regime. Prospects for tests of QED at supercritical fields that can be created in low-energy heavy-ion collisions are discussed as well., 8 pages, 1 figure, 3 tables

We review the current status of the radioisotopes program at the Soreq Applied Research Accelerator Facility (SARAF), where we utilize an electrostatic-ion-beam trap and a magneto-optical trap for studying the nuclear $\beta$-decay from trapped radioactive atoms and ions. The differential energy spectra of $\beta$'s and recoil ions emerging from the decay is sensitive to beyond standard model interactions and is complementary to high energy searches. The completed facility SARAF-II will be one of the world's most powerful deuteron, proton and fast neutron sources, producing light radioactive isotopes in unprecedented amounts, needed for obtaining enough statistics for a high precision measurement.

Magnesium- and cobalt- substituted FeSb2O4, of composition Fe1−xMgxSb2O4 (x = 0.25, 0.50, 0.75) and Fe0.25Co0.75Sb2O4 have been examined by 57Fe Mossbauer spectroscopy. The complex spectra recorded from the magnetically ordered materials are interpreted in terms of models in which the dominant magnetic interactions occur along the rutile-related chains of FeO6 octahedra in the magnetic structure of FeSb2O4. In materials of the type Fe1−xMgxSb2O4, the diamagnetic Mg2+ ions have no magnetic moment and behave as non-magnetic blocks which disrupt the magnetic interactions in the chains along the c-axis forming segments of iron-containing chains separated by Mg2+ ions. In Fe0.25Co0.75Sb2O4 the spectra are composed of components from different configurations of neighbouring Fe2+ and Co2+ ions.

We present methods to manipulate and detect the motional state and the spin state of a single antiproton or proton which are currently under development within the BASE (Baryon Antibaryon Symmetry Experiment) collaboration. These methods include sympathetic laser cooling of a single (anti-)proton using a co-trapped atomic ion as well as quantum logic spectroscopy with the two particles and could be implemented within the collaboration for state preparation and state readout in the antiproton $g$-factor measurement experiment at CERN. In our project, these techniques shall be applied using a single $^9\text{Be}^+$ ion as the atomic ion in a Penning trap system at a magnetic field of 5 T. As an intermediate step, a controlled interaction of two beryllium ions in a double-well potential as well as sympathetic cooling of one ion by the other shall be demonstrated., Proceedings of the 13th International Conference on Low Energy Antiproton Physics (LEAP 2018) Paris, France, 12-16 March 2018

A system of Y-type Ba-hexaferrite (BaSrNixCo2−xFe12O22 with x = 0.0 − 2.0) has been prepared from precursor powders synthesized by sol-gel auto-combustion method. The prepared system was investigated by XRD and Mossbauer spectroscopy (MS). The XRD patterns show the formation of the Y-type phase at a sintering temperature of 1100 ∘C. The Mossbauer spectra show pure magnetic splitting. The variations of the relative intensities of the magnetic components of the spectrum were consistent with the substitution of Nickel ions at octahedral sites. The hyperfine fields do not change appreciably with Ni substitution, due to the fact that replacement of magnetic Co2+ ions by Ni2+ ions or Fe3+ ions does not change the magnetizations of the sublattices appreciably, and consequently, does not affect the strength of the antiferromagnetic coupling between these sublattices appreciably.

A new laser spectroscopic method named “OROCHI (Optical RI-atom Observation in Condensed Helium as Ion catcher)” has been developed for deriving the nuclear spins and electromagnetic moments of low-yield exotic nuclei. In this method, we observe atomic Zeeman and hyperfine structures using laser-radio-frequency/microwave double-resonance spectroscopy. In our previous works, double-resonance spectroscopy was performed successfully with laser-sputtered stable atoms including non-alkali Au atoms as well as alkali Rb and Cs atoms. Following these works, measurements with 84−87Rb energetic ion beams were carried out in the RIKEN projectile fragment separator (RIPS). In this paper, we report the present status of OROCHI and discuss its feasibility, especially for low-yield nuclei such as unstable Au isotopes.

Heavy few-electron ions are relatively simple systems in terms of electron structure and offer unique opportunities to conduct experiments under extremely large electromagnetic fields that exist around their nuclei. However, the preparation of highly charged ions (HCI) has remained the major challenge for experiments. As an extension of the existing GSI accelerator facility, the HITRAP facility was conceived as a multi-stage decelerator for HCI produced at high velocity. It is designed to prepare bunches of around 105 HCI and to deliver them at low energies to various experiments. One of these experiments is SpecTrap, aiming for laser spectroscopy of trapped, cold HCI. We present the latest results on deceleration of ions in a radio-frequency quadrupole, synchrotron cooling of electrons in a trap as a preparation step for the prospective electron cooling of the HCI decelerated in HITRAP, as well as laser cooling of singly charged Mg ions for sympathetic cooling of HCI in SpecTrap.

The compact non-neutral plasma trap systems named “S-POD” have been developed at Hiroshima University as an experimental simulator of beam dynamics. S-POD is based either on a linear Paul trap or on a Penning trap and can approximately reproduce the collective motion of a relativistic charged-particle beam observed in the center-of-mass frame.We here employ the Paul trap system to investigate the behavior of an ion plasma near a dipole resonance. A simple method is proposed to calibrate the data of secular frequency measurements by using the dipole instability condition. We also show that the transverse density profile of an ion plasma in the trap can be estimated from the time evolution of ion losses caused by the resonance.

International audience; The LPCTrap setup is a sensitive tool to measure the β − ν angular correlation coefficient, a β ν , which can yield the mixing ratio ρ of a β decay transition. The latter enables the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element V u d . In such a measurement, the most relevant observable is the energy distribution of the recoiling daughter nuclei following the nuclear β decay, which is obtained using a time-of-flight technique. In order to maximize the precision, one can reduce the systematic errors through a thorough simulation of the whole set-up, especially with a correct model of the trapped ion cloud. This paper presents such a simulation package and focuses on the ion cloud features; particular attention is therefore paid to realistic descriptions of trapping field dynamics, buffer gas cooling and the N-body space charge effects.

Discussed are different types of high resolving mass spectrographs and spectrometers. In detail outlined are (1) magnetic and electric sector field mass spectrographs, which are the oldest systems, (2) Penning Trap mass spectrographs and spectrometers, which have achieved very high mass-resolving powers, but are technically demanding (3) time-of-flight mass spectrographs using high energy ions passing through accelerator rings, which have also achieved very high mass-resolving powers and are equally technically demanding, (4) linear time-of-flight mass spectrographs, which have become the most versatile mass analyzers for low energy ions, while the even higher performing multi-pass systems have only started to be used, (5) orbitraps, which also have achieved remarkably high mass-resolving powers for low energy ions.

We present systematic calculations of the leading order relativistic corrections including the hyperfine splitting (HFS) for a wide range of rotational and vibrational states of the HT+ molecular ion. We also calculate the DC and AC Stark effects for the molecular hydrogen ions \(H_{2}^{+}\) and HD+ in the non-relativistic approximation. The influence of the DC Stark polarizability effect on the hyperfine substates of a ro-vibrational state is carefully analyzed. Our results enable the detailed evaluation of certain systematic shifts of the transition frequencies for the purpose of ultra-high-precision optical, microwave, or radio-frequency spectroscopy of the hydrogen molecular ions in a trap.

We performed classical molecular dynamics (MD) simulations in order to search the conditions for efficient sympathetic cooling of highly charged ions (HCIs) in a linear Paul trap. Small two-component ion Coulomb crystals consisting of laser-cooled ions and HCIs were characterized by the results of the MD simulations.We found that the spatial distribution is determined by not only the charge-to-mass ratio but also the space charge effect. Moreover, the simulation results suggest that the temperature of HCIs do not necessarily decrease with increasing the number of laser-cooled ions in the cases of linear ion crystals. We also determined the cooling limit of sympathetically cooled 165Ho14+ ions in small linear ion Coulomb crystals. The present results show that sub-milli-Kelvin temperatures of at least 10 Ho14+ ions will be achieved by sympathetic cooling with a single laser-cooled Be+.

At TRIUMF’s Ion Trap for Atomic and Nuclear Science (TITAN) a multiplereflection time-of-flight mass spectrometer (MR-TOF-MS) will extend TITAN’s capabilities and facilitate mass measurements and in-trap decay spectroscopy of exotic nuclei that so far have not been possible due to strong isobaric contaminations. This MR-TOF-MS will also enable mass measurements of very short-lived nuclides (half-life > 1 ms) that are produced in very low quantities (a few detected ions overall). In order to allow the installation of an MR-TOF-MS in the restricted space on the platform, on which the TITAN facility is located, novel mass spectrometric methods have been developed. Transport, cooling and distribution of the ions inside the device is done using a buffer gas-filled RFQ-based ion beam switchyard. Mass selection is achieved using a dynamic retrapping technique after time-of-flight analysis in an electrostatic isochronous reflector system. Only due to the combination of these novel methods the realization of an MR-TOF-MS based isobar separator at TITAN has become possible. The device has been built, commissioned off-line and is currently under installation at TITAN.

We present new theoretical results for the transition energies of the hydrogen isotope molecular ions and antiprotonic helium atoms. Our consideration includes corrections at the mα7 order in the nonrecoil limit such as the one-loop self-energy, one-loop vacuum polarization, Wichman-Kroll, and complete two-loop contributions. That allowed to get transition energies for the fundamental transition \((v = 0,L = 0)\rightarrow (1,0)\) in the hydrogen molecular ion with the relative theoretical uncertainty of ∼7⋅10−12 that corresponds to a fractional precision of 1.5⋅10−11 in determination of the electron-to-proton mass ratio, mp/me. Correspondingly, for the two-photon transitions in the antiprotonic helium we have 4.7⋅10−11 as a relative uncertainty for the \((33,32)\rightarrow (31,30)\) transition frequency and a fractional precision of 3.6⋅10−11 for an inferred antiproton-to-electron mass ratio.

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.

The Effective Hamiltonian of the hydrogen molecular ions is a convenient tool for the evaluation of the shift of the energy levels of the ro-vibrational states and the frequencies of the transitions between them, due to external electric and magnetic fields. Using the Effective Hamiltonian, composite frequencies of suppressed susceptibility to external fields are constructed.

Precession of aligned nuclear spin systems in ions recoiling from the target into vacuum (RIV) with consequent attenuation of angular distributions of emitted radiation is, in principle, a versatile method for measurement of g-factors of nuclear excited states of lifetimes in the pico-second range (Stone et al., Phys. Rev. Lett., 94, 192501, 2005 and Stuchbery and Stone, Phys. Rev. C, 76, 034307, 2007). Calibration of the observed attenuations has been achieved in favourable cases through comparison with measurements on states having previously known g-factors and lifetimes. The general lack of suitable states with known g-factors has limited application of the RIV method. This paper concerns the present status of efforts to describe the states of excited ions recoiling into vacuum in detail so that the average interaction can be estimated with useful precision from a-priori theory. The calculations use the GRASP2K package (Froese-Fischer et al. 1997 and Jonsson, Comp. Phys. Comm., 177, 597, 2007 & 184, 2197, 2013) to obtain, for each recoiling ion change state, the individual possible electronic states, their configurations, lifetimes and hyperfine interactions. It is assumed that all possible ionic states are produced, up to a chosen excitation energy. This energy is selected to approximate the energy at which all states have lifetimes far shorter than the nuclear state of interest. It is further assumed that the ionic state total electron angular momenta are randomly oriented in space. The first estimates of the average attenuation of emission distributions, as a function of the product g τ of the nuclear state g-factor and mean lifetime, used an averaged precession frequency obtained neglecting transitions between electronic states. Improved calculations, which include such transitions, are described.

Conversion electron Mossbauer Spectroscopy (CEMS) measurements were made on a ZnO single crystal sample implanted at room temperature (RT) with of 145 and 345 keV 59Co ions with respective fluences of 1.15×1016 ions/cm 2 and 4.17×1016 ions/cm 2, followed by implantation of 60 keV 57Fe to a fluence of 0.50×1016/cm 2 to yield a ‘box-shaped’ implantation profile with a Co + Fe concentration of about 3.2 at. %. CEM spectra were collected after annealing the sample up to 973 K. The spectra after annealing up to 973 K are similar to spectra observed in other CEMS studies on Fe implanted ZnO, but show a dramatic change after the 973 K annealing step; it is dominated by a doublet component with fit parameters typical of Fe 3+. Magnetization curves of the sample after the 973 K anneal show hysteresis, with a small residual magnetization at RT that increases at 4 K. The saturation magnetization at 4 K was approximately 0.33 μB/CoFe ion, in good agreement with observations for 5–8 nm sized Co nanoclusters in ZnO.

Being the main cause of cancer, almost all chemical carcinogens are strong electrophiles, that is, they have a high affinity for the electron. We have shown that positron annihilation lifetime spectroscopy (PALS) is able to detect chemical carcinogens by their inhibition of positronium (Ps) formation in liquid media. Electrophilic carcinogens intercept thermalized track electrons, which are precursors of Ps, and as a result, when they are present Ps atom does not practically form. Available biophysical data seemingly indicate that frozen solutions model better an intracellular medium than the liquid ones. So it is reasonable to use emission Mossbauer spectroscopy (EMS) to detect chemical carcinogens, measuring the yield of 57Fe2+ions formed in reactions of Auger electrons and other secondary electrons they produced with 57Fe3+. These reactions are similar to the Ps formation process in the terminal part the positron track: e++ e− =>Ps. So EMS and PALS are complementary methods for detection of carcinogenic compounds.

Understanding the structure of oxygen evolving complex (OEC) fully still remains a challenge. Lately computational chemistry with the data from more detailed X-ray diffraction (XRD) OEC structure, has been used extensively in exploring the mechanisms of water oxidation in the OEC (Gatt et al., J. Photochem. Photobiol. B 104(1–2), 80–93 2011). Knowledge of the oxidation states is very crucial for understanding the core principles of catalysis by photosystem II (PSII) and catalytic mechanism of OEC. The present study involves simulation studies of the X-band continuous wave electron-magnetic resonance (CW-EPR) generated S 2 state signals, to investigate whether the data is in agreement with the four manganese ions in the OEC, being organised as a ‘3 + 1’ (trimer plus one) model (Gatt et al., Angew. Chem. Int. Ed. 51, 12025–12028 2012; Petrie et al., Chem. A Eur. J. 21, 6780–6792 2015; Terrett et al., Chem. Commun. (Camb.) 50, 8–11 2014) or ‘dimer of dimers’ model (Terrett et al. 2016). The question that still remains is how much does each Mn ion contribute to the “ g2multiline” signal through its hyperfine interactions in OEC also to differentiate between the ‘high oxidation state (HOS)’ and ‘low oxidation state (LOS)’ paradigms? This is revealed in part by the structure of multiline (ML) signal studied in this project. Two possibilities have been proposed for the redox levels of the Mn ions within the catalytic cluster, the so called ‘HOS’ and ‘LOS’ paradigms (Gatt et al., J. Photochem. Photobiol. B 104(1–2), 80–93 2011). The method of data analysis involves numerical simulations of the experimental spectra on relevant models of the OEC cluster. The simulations of the X-band CW-EPR multiline spectra, revealed three manganese ions having hyperfine couplings with large anisotropy. These are most likely Mn III centres and these clearly support the ‘LOS’ OEC paradigm model, with a mean oxidation of 3.25 in the S2 state. This is consistent with the earlier data by Jin et al. (Phys. Chem. Chem. Phys. (PCCP) 16(17), 7799–812 2014), but the present results clearly indicate that heterogeneity in hyperfine couplings exist in samples as typically prepared.

The X. international workshop on “Application of Lasers and Storage Devices in Atomic Nuclei Research” took place in Poznan in May 2016. It addressed the latest experimental and theoretical achievements in laser and ion trap-based investigations of radionuclides, highly charged ions and antiprotons. The precise determination of atomic and nuclear properties provides a stringent benchmark for theoretical models and eventually leads to a better understanding of the underlying fundamental interactions and symmetries. This article addresses some general trends in this field and highlights select recent achievements presented at the workshop. Many of these are covered in more detail within the individual contributions to this special issue of Hyperfine Interactions.