Klaus Wendt

• Prof. Dr.
• Group Leader at Johannes Gutenberg University Mainz

Die berufliche und gesellschaftliche Relevanz des Studiums prägt sowohl aktuelle bildungspolitische Diskussionen als auch die Leitmotive vieler deutscher Hochschulen. Im Laufe des Studiums sollen Studierende zum einen berufsrelevante Kompetenzen erwerben und zum anderen in ihrer persönlichen und gesellschaftsrelevanten Entwicklung gefördert werden....

DOI:https://doi.org/10.1103/PhysRevC.109.059901

Kurzfassung Virtual-Reality-Experimente sind anspruchsvolle Simulationen von typischen Schulexperimenten in einer dreidimensionalen Umgebung, mit weitreichenden didaktischen sowie Interaktionsmöglich-keiten. Sie können auf diversen Unterrichtsmedien überall dort eingesetzt werden, wo reale Schul-experimente nicht (mehr) verfügbar sind oder sich dur...

„Augmented Reality” (erweiterte Realität, kurz AR) ermöglicht die Ergänzung einer realen Umge- bung mit virtuellen Objekten, Einblendungen oder Erläuterungen. So ist eine Simulation von Expe- rimenten in natürlicher Umgebung ohne Abstraktion auf schematische Darstellungen möglich, was die Schüler:innen den realen Ablauf des Experimentierens „begrei...

Kurzfassung Hochschulen haben als Schnittstelle zwischen Lehre, Forschung und Transfer ein großes Potenzial, die Gesellschaft nachhaltiger zu gestalten. Einzelne Fachdisziplinen sind im Hinblick auf die ange-botenen Lehrveranstaltungen im Bereich Klimawandel und Nachhaltigkeit inhaltlich stark vonei-nander getrennt und den Studierenden fehlt eine g...

Kurzfassung Virtual-Reality-Experimente (VRE) stellen realistische 3D-Simulationen naturwissenschaftlicher Versuche dar. Innerhalb einer realitätsnah modellierten und damit authentischen digitalen Laborum-gebung kann mit den Experimenten und den zur Verfügung stehenden Geräten frei und selbstge-steuert experimentiert werden. Dabei werden diejenigen...

If education is to prepare learners for lifelong learning, there needs to be a shift towards deeper learning: a focus on transferable knowledge and problem-solving skills alongside the development of a positive or growth mind-set. Deeper learning is inextricably linked with CLIL (Content and Language Integrated Learning) – a revolutionary teaching...

Im Projekt „Lehr-Lern-Forschungslabore als Orte vertieften Lernens: Das Mainzer Modell kooperativer Lehrerbildung" der BMBF Qualitätsoffensive Lehrerbildung partizipieren Studierende des gymnasialen Lehramtsstudiengangs im Teilprojekt Physik an Lehr-Lern-Labor-Seminaren. Diese sind an bildungswissenschaftliche Veranstaltungen im Bachelor- und Maste...

Der Physikunterricht lebt von seinen Experimenten und von der aktiven Auseinandersetzung mit physikalischen Phänomenen und Untersuchungsgegenständen. Es gibt aber Versuche, die aus ver-schiedensten Gründen nicht oder nur erschwert im Unterricht durchgeführt werden können. Als Gründe zu nennen sind hohe Gefahrenquellen, die von bspw. radioaktiven St...

Die Sicherung von Lernergebnissen stellt einen zentralen Teil von Lehr-Lernprozessen im Physikunterricht dar und bezweckt eine nachhaltige Integration des Lernzugewinns in das bereits bestehende Wissensnetz der Schüler:innen. Bisher finden die Planung und Gestaltung von Lernergebnissicherungen im Physikunterricht jedoch nur sehr wenig Beachtung in...

Die Sicherung von Lernergebnissen ist die zentrale Gelingensbedingung für den erfolgreichen Ab- schluss von Lehr- und Lernprozessen. Trotz dieser zentralen Rolle für das unterrichtliche Handeln liefern fachdidaktische Standardwerke keine einheitliche Aussage darüber, was unter Lernergebnissicherung zu verstehen ist und welche Kriterien an die unter...

Kurzfassung Virtual-Reality-Experimente (VRE) stellen realistische 3D-Simulationen naturwissenschaftlicher Versuche dar. Dabei werden vorrangig Experimente umgesetzt, von denen Gefahrenpotentiale aus-gehen oder deren Anschaffung für die Schule zu teuer ist. VRE ermöglichen den Schüler:innen zu-dem eine direkte Partizipation durch ihre digitale Verf...

"Climate Escape" ist ein interaktives Schülerlabor in Form eines Escape Rooms zu den Themen "Klimawandel" und "Nachhaltigkeit". Schulklassen können das Escape Game mit Modellversu-chen im NaTLab Physik der Johannes Gutenberg-Universität (JGU) Mainz durchleben. Der Escape Game -Ansatz bietet eine Möglichkeit, physikalische Inhalte spielerisch zu ver...

Schülerexperimente stellen insbesondere im Physikun- terricht ein didaktisches Mittel dar, um Schülerinnen und Schüler zu aktivie- ren, sich selbstgesteuert mit physikbezogenen Inhalten auseinanderzusetzen. Dabei wird in aller Regel auf kooperative Lernsettings gesetzt, in denen Schülerinnen und Schüler gemeinschaftlich nach Lösungen suchen. Entspr...

We present the results of a National Science Foundation Project Scoping Workshop, the purpose of which was to assess the current status of calculations for the nuclear matrix elements governing neutrinoless double-beta decay and determine if more work on them is required. After reviewing important recent progress in the application of effective fie...

We present the results of a National Science Foundation (NSF) Project Scoping Workshop, the purpose of which was to assess the current status of calculations for the nuclear matrix elements governing neutrinoless double-beta decay and determine if more work on them is required. After reviewing important recent progress in the application of effecti...

Bei Climate Escape der Johannes Gutenberg-Universität Mainz handelt es sich um ein didaktisches Angebot in Form eines Escape Room Games. Im Rahmen des Schülerlabors NaTLab-Physik wird es dabei ermöglicht, Hintergründe des Klimawandels kennen zu lernen und Kompetenzen zum Klimaschutz zu entwickeln. Schüler/innen können es in Form eines interaktiven...

Isotope shifts of Ra223–226,228F19 were measured for different vibrational levels in the electronic transition A2Π1/2←X2Σ+. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the electronic density within the radium nucleus. Ab init...

Isotope shifts of $^{223-226,228}$Ra$^{19}$F were measured for different vibrational levels in the electronic transition $A^{2}{}{\Pi}_{1/2}\leftarrow X^{2}{}{\Sigma}^{+}$. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the elec...

The CERN-MEDICIS facility aims to produce emerging medical radionuclides for the theranostics approach in nuclear medicine with mass separation of ion beams. To enhance the radioisotope yield and purity of collected samples, the resonance ionization laser ion source MELISSA was constructed, and provided the first laser ions at the facility in 2019....

„Augmented Reality“ (kurz AR) ermöglicht die Ergänzung einer realen Umgebung mit virtuellen Objekten, Einblendungen und der Einbindung von Erläuterungen. So ist eine Simulation von Experimenten als Demonstrations- oder Schülerversuch in natürlicher Umgebung mit authentischen Repräsentationen möglich, die ohne Abstraktion auf schematische Darstellun...

Two lowest-energy odd-parity atomic levels of actinium, 7s27p2Po1/2, 7s27p2Po3/2, were observed via two-step resonant laser-ionization spectroscopy and their respective energies were measured to be 7477.36(4) and 12276.59(2) cm−1. The lifetimes of these states were determined as 668(11) and 255(7) ns, respectively. In addition, we observed the effe...

Nuclear charge radii globally scale with atomic mass number A as A1∕3, and isotopes with an odd number of neutrons are usually slightly smaller in size than their even-neutron neighbours. This odd–even staggering, ubiquitous throughout the nuclear landscape¹, varies with the number of protons and neutrons, and poses a substantial challenge for nucl...

Molecular spectroscopy offers opportunities for the exploration of the fundamental laws of nature and the search for new particle physics beyond the standard model1–4. Radioactive molecules—in which one or more of the atoms possesses a radioactive nucleus—can contain heavy and deformed nuclei, offering high sensitivity for investigating parity- and...

Two lowest-energy odd-parity atomic levels of actinium, 7s^27p 2P^o_1/2, 7s^27p 2P^o_3/2, were observed via two-step resonant laser-ionization spectroscopy and their respective energies were measured to be 7477.36(4) cm^-1 and 12 276.59(2) cm^-1. The lifetimes of these states were determined as 668(11) ns and 255(7) ns, respectively. In addition, t...

The novel and sensitive In-Gas Laser Ionization Spectroscopy (IGLIS) technique enables high-precision laser spectroscopy of the heaviest elements and isotopes very far from stability that are produced in fusion-evaporation reactions at in-flight separators. Powerful and dedicated laser systems are required in these facilities to realize in-gas jet...

With increasing demand for accurate calculation of isotope shifts of atomic systems for fundamental and nuclear structure research, an analytic energy derivative approach is presented in the relativistic coupled-cluster (CC) theory framework to determine the atomic field shift and mass shift (MS) factors. This approach allows the determination of e...

With increasing demand for accurate calculation of isotope shifts of atomic systems for fundamental and nuclear structure research, an analytic energy derivative approach is presented in the relativistic coupled-cluster (CC) theory framework to determine the atomic field shift and mass shift (MS) factors. This approach allows the determination of e...

The specific heat of dilute holmium alloys plays a major role in the optimization of low temperature microcalorimeters with enclosed $^{163}\textrm{Ho}$, such as the ones developed for the neutrino mass experiment ECHo. We investigate alloys with atomic concentrations of $x_\textrm{Ho}=0.01\,\% - 4\,\%$ at temperatures between $10\,\textrm{mK}$ and...

Abstract The determination of the effective electron neutrino mass via kinematic analysis of beta and electron capture spectra is considered to be model-independent since it relies on energy and momentum conservation. At the same time the precise description of the expected spectrum goes beyond the simple phase space term. In particular for electro...

Multistep laser-resonance-ionization spectroscopy of tellurium (Te) has been performed at TRIUMF's off-line laser ion source test stand. Six clean and regular even-parity Rydberg series 5p3(S43/2∘)npP0,1,23, npP1,25, and nfF23/F1,25 were observed. The ionization potential of Te was extracted from the measured series as 72669.114(56)stat(45)syscm−1....

The mesoscopic nature of the atomic nucleus gives rise to a wide array of macroscopic and microscopic phenomena. The size of the nucleus is a window into this duality: while the charge radii globally scale as $A^{1/3}$, their evolution across isotopic chains reveals unanticipated structural phenomena. The most ubiquitous of these is perhaps the Odd...

The study of molecular systems provides exceptional opportunities for the exploration of the fundamental laws of nature and for the search for physics beyond the Standard Model of particle physics. Measurements of molecules composed of naturally occurring nuclei have provided the most stringent upper bounds to the electron electric dipole moment to...

The production of selenium ion beams has been investigated at the CERN-ISOLDE facility via two different ionization methods. Whilst molecular selenium (SeCO) beams were produced at ISOLDE since the early 1990s, recent attempts at reliably reproducing these results have so far been unsuccessful. Here we report on tests of a step-wise resonance laser...

Precision nuclear charge radii measurements in the light-mass region are essential for understanding the evolution of nuclear structure, but their measurement represents a great challenge for experimental techniques. At the Collinear Resonance Ionization Spectroscopy (CRIS) setup at ISOLDE-CERN, a laser frequency calibration and monitoring system w...

We demonstrate a highly efficient, tunable, ∼ 5 GHz linewidth diamond Raman laser operating at 479 nm. The diamond laser was pumped by a wavelength-tunable intracavity frequency-doubled titanium sapphire (Ti:Sapphire) laser operating at around 450 nm, at a repetition rate of 10 kHz with a pulse duration of 50 ns. The Raman resonator produced a cont...

The effective electron neutrino mass measurement in the framework of the ECHo experiment requires radiochemically pure ¹⁶³Ho, which is ion implanted into detector absorbers. To meet the project specifications in efficiency and purity, the entire process chain of ionization, isotope separation, and implantation of ¹⁶³Ho was optimized. A new two-step...

Resonance ionization schemes for tellurium are investigated with a resonance ionization laser ion source and Ti:Sapphire lasers for fundamental research applications. We present the first three-step resonance ionization spectra of atomic Te. Several autoionizing Rydberg series converging to the first excited state of Te+ are observed and assigned t...

The atomic spectrum of neutral promethium has been studied extensively by laser resonance ionization spectroscopy. We report on more than 1000 atomic transitions in the blue and near infrared spectral ranges, most of them between high excited energy levels. As Rydberg convergences could not be assigned unambiguously in the dense spectrum at high ex...

Resonance ionization mass spectrometry is an efficient tool to detect minute amounts of long-lived radio-isotopes in environmental samples. Applying resonant excitation and ionization with pulsed laser radiation within a hot cavity atomizer enables the sensitive detection and precise quantification of long-lived actinide isotopes. Due to the inhere...

The development of a highly efficient resonance ionization scheme for lutetium is presented. A laser ion source, based on the all-solid-state Titanium:sapphire laser system, was used at the 30 keV RISIKO off-line mass separator to characterize different possible optical excitation schemes in respect to their ionization efficiency. The developed las...

Hyperfine-structure parameters and isotope shifts for the 795-nm atomic transitions in At217,218,219 have been measured at CERN-ISOLDE, using the in-source resonance-ionization spectroscopy technique. Magnetic dipole and electric quadrupole moments, and changes in the nuclear mean-square charge radii, have been deduced. A large inverse odd-even sta...

A compact radio frequency cooler buncher (RFQCB) is currently in development between The University of Manchester, KU Leuven, and CERN. The device will be installed as part of the Collinear Resonance Ionisation Spectroscopy (CRIS) experiment at the Isotope sep-arator On-line device (ISOLDE) at CERN. The purpose of developing a dedicated RFQCB for t...

The dominant decay mode of atomic nuclei is beta decay (β-decay), a process that changes a neutron into a proton (and vice versa). This decay offers a window to physics beyond the standard model, and is at the heart of microphysical processes in stellar explosions and element synthesis in the Universe 1–3 . However, observed β-decay rates in nuclei...

The Gothenburg ANion Detector for Affinity measurements by Laser PHotodetachment (GANDALPH)has recently been built for measurements of electron affinities (EA)of radioisotopes. A first measurement campaign is aimed towards the determination of the EA of astatine, the rarest naturally occurring element on earth. In this work we present several upgra...

The Resonance Ionization Laser Ion Source (RILIS) has become an essential feature of many radioactive ion beam facilities worldwide since it offers an unmatched combination of efficiency and selectivity in the production of ion beams of many different chemical elements. In 2019, the laser ion source setup MELISSA is going to be established at the C...

Ion sources exploiting laser resonance ionization offer efficient and element-selective radioactive ion beam production at the leading isotope separation on-line facilities worldwide. Most commonly, laser resonance ionization takes place inside a resistively heated atomizer tube directly coupled to the production target, where the element of intere...

To measure the mass of the electron neutrino, the “Electron Capture in Holmium-163” (ECHo) collaboration aims at calorimetrically measuring the spectrum following electron capture in ¹⁶³Ho. The success of the ECHo experiment depends critically on the radiochemical purity of the ¹⁶³Ho sample, which is ion-implanted into the calorimeters. For this, a...

Neutron-deficient Hg177−185 isotopes were studied using in-source laser resonance-ionization spectroscopy at the CERN-ISOLDE radioactive ion-beam facility in an experiment combining different detection methods tailored to the studied isotopes. These include either α-decay tagging or multireflection time-of-flight gating for isotope identification....

The effective electron neutrino mass measurement at the ECHo experiment requires high purity $^{163}$Ho, which is ion implanted into detector absorbers. To meet the project specifications in efficiency and purity, the entire process chain of ionization, isotope separation, and implantation of $^{163}$Ho was optimized. A new two-step resonant laser...

Quadrupole ion traps are modern and versatile research tools used in mass spectrometers, in atomic frequency and time standards, in trapped ion quantum computing research, and for trapping anti-hydrogen ions at CERN. Despite their educational potential, quadrupole ion traps are seldom introduced into the physics classroom not least because commerci...

Erbium ¹⁶⁹ Er is one of the most interesting radiolanthanides for new potential receptor-targeted β ⁻ therapy applications due to its low energy β ⁻ emissions, very low intensity ɣ rays and the possibility to use ⁶⁸ Ga or ⁴⁴ Sc as companion for diagnostic in a theranostics approach. Currently it can be produced in reactors through the neutron activ...

Collinear Doppler-free 2-photon resonance ionization has been applied inside a hot cavity laser ion source environment at CERN-ISOLDE. An injection-seeded Ti:sapphire ring laser was used to generate light pulses with a Fourier-limited linewidth for high-resolution spectroscopy. Using a molybdenum foil as a reflective surface positioned at the end o...

A number of radiogenically produced dysprosium isotopes have been studied by in-source laser spectroscopy at ISOLDE using the Resonance Ionization Laser Ion Source (RILIS). Isotope shifts were measured relative to 152Dy in the 4f ¹⁰ 6s ² 5I 8 (gs)→4f ¹⁰ 6s6p (8,1) 8o (418.8nm vac )resonance transition. The electronic factor, F, and mass shift facto...

Neutron-deficient $^{177-185}$Hg isotopes were studied using in-source laser resonance-ionization spectroscopy at the CERN-ISOLDE radioactive ion-beam facility, in an experiment combining different detection methods tailored to the studied isotopes. These include either alpha-decay tagging or Multi-reflection Time-of-Flight gating to identify the i...

\beta$-decay, a process that changes a neutron into a proton (and vice versa), is the dominant decay mode of atomic nuclei. This decay offers a unique window to physics beyond the standard model, and is at the heart of microphysical processes in stellar explosions and the synthesis of the elements in the Universe. For 50 years, a central puzzle has...

A neutral particle detector is presented, in which the traditionally used target material, indium tin oxide (ITO), is replaced by graphene. The graphene-based detector enables collinear photodetachment measurements at a significantly shorter wavelength of light down to 230 nm compared to ITO-based detectors, which are limited at 335 nm. Moreover, t...

Calculations of the neutralisation cross-section and relative population of atomic states were performed for ions beams (1 ≤ Z ≤ 89) at 5 and 40 keV incident on free sodium and potassium atoms. To test the validity of the calculations, the population distribution of indium ions incident on a vapour of sodium was measured at an intermediate energy o...

We demonstrate a highly efficient, continuously tunable, diamond Raman laser operating in the blue region of the spectrum. The linewidth and tunability characteristics of a frequency-doubled Ti:Sapphire laser were transferred directly to the Stokes output, offering great potential for spectroscopic applications using an all-solid-state platform.

In rare cases, the removal of a single proton (Z) or neutron (N) from an atomic nucleus leads to a dramatic shape change. These instances are crucial for understanding the components of the nuclear interactions that drive deformation. The mercury isotopes (Z = 80) are a striking example1,2: their close neighbours, the lead isotopes (Z = 82), are sp...

We present a direct excitation of the presumably ultranarrow 1001−nm ground-state transition in atomic dysprosium. By using resonance ionization spectroscopy with pulsed Ti:sapphire lasers at a hot cavity laser ion source, we were able to measure the isotopic shifts in the 1001−nm line between all seven stable isotopes. Furthermore, we determined t...

We demonstrate that the pulsed-time structure and high-peak ion intensity provided by the laser-ablation process can be directly combined with the high resolution, high efficiency, and low background offered by collinear resonance ionization spectroscopy. This simple, versatile, and powerful method offers new and unique opportunities for high-preci...

This paper reports on resonance ionization scheme development for the production of exotic radium ion beams with the Resonance Ionization Laser Ion Source (RILIS) of the CERN-ISOLDE radioactive ion beam facility. During the study, autoionizing states of atomic radium were observed for the first time. Three ionization schemes were identified, origin...

To measure the mass of the electron neutrino, the "Electron Capture in Holmium-163" (ECHo) collaboration aims at calorimetrically measuring the spectrum following electron capture in $^{163}$Ho. The success of the ECHo experiment depends critically on the radiochemical purity of the $^{163}$Ho sample, which is ion-implanted into the calorimeters. F...

Recently, spectroscopic investigations of the protactinium atom applying resonant laser ionization spectroscopy revealed high-resolution data of the single-excitation spectrum of protactinium, reaching slightly beyond the first ionization potential [P. Naubereit et al., preceding paper, Phys. Rev. A 98, 022505 (2018)]. The more than 1500 recently d...

We present high-resolution data of the single-excitation spectrum of protactinium, reaching slightly beyond the first-ionization threshold. Within this work, more than 1500 energy levels are recorded in different excitation energy ranges below 50000cm−1. Our experimental results show that the tabulated data in the literature severely underestimate...

We present the first direct excitation of the presumably ultra-narrow $1001 \, \textrm{nm}$ ground state transition in atomic dysproium. By using resonance ionization spectroscopy with pulsed Ti:sapphire lasers at a hot cavity laser ion source, we were able to measure the isotopic shifts in the $1001 \, \textrm{nm}$ line between all seven stable is...

Hyperfine-structure parameters and isotope shifts of At195–211 have been measured for the first time at CERN-ISOLDE, using the in-source resonance-ionization spectroscopy method. The hyperfine structures of isotopes were recorded using a triad of experimental techniques for monitoring the photo-ion current. The Multi-Reflection Time-of-Flight Mass...

The newly developed resonant laser–SNMS system at the IRS Hannover combines the high spatial and decent mass resolution of a TOF-SIMS instrument with the element-selective process of resonant laser ionization. This setup was characterized by use of synthetic uranium, plutonium and technetium samples to prepare and demonstrate the performance for me...

Several experiments on the study of the electron neutrino mass are based on high-statistics measurements of the energy spectrum following electron capture of the radionuclide ¹⁶³Ho. They rely on the availability of large, radiochemically pure samples of ¹⁶³Ho. Here, we describe the production, separation, characterization, and sample production wit...

The neutron-rich radium isotopes, Ra222−233, were measured with Collinear Resonance Ionization Spectroscopy (CRIS) at the ISOLDE facility, CERN. The hyperfine structure of the 7s2S01→7s7pP13 transition was probed, allowing measurement of the magnetic moments, quadrupole moments, and changes in mean-square charge radii. These results are compared to...

We demonstrate the efficient generation of Be$^+$ ions with a 60 ns and 150 nJ laser pulse near 235 nm for two-step photo-ionization, proven by subsequent counting the number of ions loaded into a linear Paul trap. The bandwidth and power of the laser pulse are chosen in such a way that a first, resonant step fully saturates the entire velocity dis...

The in-gas laser ionization and spectroscopy (IGLIS) technique was applied on the Ac212–215 isotopes, produced at the Leuven Isotope Separator On-Line (LISOL) facility by using the in-gas-cell and the in-gas-jet methods. The first application under on-line conditions of the in-gas-jet laser spectroscopy method showed a superior performance in terms...

We report on resonance ionization spectroscopy (RIS) of high-lying energy levels in dysprosium. We developed efficient excitation schemes and re-determined the first ionization potential (IP) via analysis of Rydberg convergences. For this purpose both two- and three-step excitation ladders were investigated. An overall ionization efficiency of 25(4...

Nuclear spins and precise values of the magnetic dipole and electric quadrupole moments of the ground states of neutron-rich Cu73–78 isotopes were measured using the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at the CERN On-Line Isotope Mass Separator (ISOLDE) facility. The nuclear moments of the less exotic Cu73,75 isotopes were...

The first experimental investigation of the electron affinity (EA) of a radioactive isotope has been conducted at the CERN-ISOLDE radioactive ion beam facility. The EA of the radioactive iodine isotope ¹²⁸I (t1/2 = 25 min) was determined to be 3.059 052(38) eV. The experiment was conducted using the newly developed Gothenburg ANion Detector for Aff...

Localization, analysis and mobility of radioactive contaminated particles is of major concern for assessment of contamination threads and nuclear forensics. For this purpose, a new resonant Laser-SNMS system was developed and set up at the Institute for Radioecology and Radiation Protection for spatially resolved ultra-trace analysis of low concent...

Nuclear spins and precise values of the magnetic dipole and electric quadrupole moments of the ground-states of neutron-rich $^{76-78}$Cu isotopes were measured using the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at ISOLDE, CERN. The nuclear moments of the less exotic $^{73,75}$Cu isotopes were re-measured with similar precision...

The spectroscopic electric quadrupole moment of the neutron-deficient francium isotope Fr203 was measured by using high-resolution collinear resonance ionization spectroscopy (CRIS) at the CERN Isotope Separation On-Line Device (ISOLDE) facility. A remeasurement of the Fr207 quadrupole moment was also performed, resulting in a departure from the es...

A high repetition rate pulsed Ti:sapphire laser injection-locked to a continuous wave seed source is presented. A spectral linewidth of 20 MHz at an average output power of 4 W is demonstrated. An enhanced tuning range from 710–920 nm with a single broadband mirror set is realized by the inclusion of a single thin birefringent quartz plate for supp...

At ISOLDE the majority of radioactive ion beams are produced using the resonance ionization laser ion source (RILIS). This ion source is based on resonant excitation of atomic transitions by wavelength tunable laser radiation. Since its installation at the ISOLDE facility in 1994, the RILIS laser setup has been developed into a versatile remotely o...

Neutrinos, and in particular their tiny but non-vanishing masses, can be considered one of the doors towards physics beyond the Standard Model. Precision measurements of the kinematics of weak interactions, in particular of the 3H β-decay and the 163Ho electron capture (EC), represent the only model independent approach to determine the absolute sc...

Several novel experiments designed to investigate the electron neutrino mass in the sub-eV region are based on the calorimetric measurement of the ¹⁶³Ho electron capture spectrum. For this the ¹⁶³Ho source, with a required activity of the order of 1 to 100Bq, needs to be enclosed in the detector, having a volume smaller than 10−3mm3. Ion implantati...

Multi-step resonance ionization spectroscopy of cobalt has been performed using a hot-cavity laser ion source and three Ti:Sapphire lasers. The photoionization spectra revealed members of five new autoionizing Rydberg series that originate from three different lower levels of 3d ⁷4s5s h ⁴F9/2, 3d ⁷4s4d f ⁴G11/2, and 3d ⁷4s4d f ⁴H13/2 and converge t...

Long-lived isotopes of plutonium were studied using two complementary techniques, high-resolution resonance ionisation spectroscopy (HR-RIS) and collinear laser spectroscopy (CLS). Isotope shifts have been measured on the $5f^67s^2\ ^7F_0 \rightarrow 5f^56d^27s\ (J=1)$ and $5f^67s^2\ ^7F_1 \rightarrow 5f^67s7p\ (J=2)$ atomic transitions using the H...

This paper presents the results of ionization scheme development for application at the ISOLDE Resonance Ionization Laser Ion Source (RILIS). Two new ionization schemes for mercury are presented: a three-step three-resonance ionization scheme, ionizing via an excitation to a Rydberg level and a three-step two-resonance ionization scheme, with a non...

Resonant laser ionization and spectroscopy are widely used techniques at radioactive ion beam facilities to produce pure beams of exotic nuclei and measure the shape, size, spin and electromagnetic multipole moments of these nuclei. However, in such measurements it is difficult to combine a high efficiency with a high spectral resolution. Here we d...

Odd-parity autoionizing states of europium have been investigated by resonance ionization spectroscopy via two-step, two-resonance excitations. The aim of this work was to establish ionization schemes specifically suited for europium ion beam production using the ISOLDE Resonance Ionization Laser Ion Source (RILIS). 13 new RILIS-compatible ionizati...

The MEDICIS-PROMED Innovative Training Network under the Horizon 2020 EU program aims to establish a network of early stage researchers, involving scientific exchange and active cooperation between leading European research institutions, universities, hospitals, and industry. Primary scientific goal is the purpose of providing and testing novel rad...

Resonance ionization mass spectrometry is an efficient tool for detecting trace amounts of long-lived radio-isotopes in environmental samples. For absolute quantification a tracer with identical atomic properties and chemical behavior is needed to prevent a possible dependency onto the absolute efficiency for the analytical method. For an applicati...

Operation of the novel laser ion source unit LIST (Laser Ion Source and Trap), operating at the on-line radioactive ion beam facility ISOLDE at CERN allowed for the production of ultra-pure beams of exotic isotopes far-off stability as well as direct isobar-free laser spectroscopy, giving access to the study of atomic and nuclear properties of so f...

DOI:https://doi.org/10.1103/PhysRevC.94.059903