71 citations · 353 across the 16 of their papers we have counts for
16 papers
Combining laser cooling and Zeeman deceleration for precision spectroscopy in supersonic beams
Gloria Clausen, Laura Gabriel, Josef A. Agner +4
Precision spectroscopic measurements in atoms and molecules play an increasingly important role in chemistry and physics, e.g., to characterize structure and dynamics at long times…
Metrology in a two-electron atom: The ionization energy of metastable triplet helium ()
Gloria Clausen, Kai Gamlin, Josef A. Agner +2
Helium (He) is the ideal atom to perform tests of ab-initio calculations in two-electron systems that consider all known effects, including quantum-electrodynamics and nuclear-size…
Imaging-assisted single-photon Doppler-free laser spectroscopy and the ionization energy of metastable triplet helium
Gloria Clausen, Simon Scheidegger, Josef A. Agner +2
Skimmed supersonic beams provide intense, cold, collision-free samples of atoms and molecules are one of the most widely used tools in atomic and molecular laser spectroscopy. High…
Multipole-moment effects in ion-molecule reactions at low temperatures: part I -- Ion-dipole enhancement of the rate coefficients of the He + NH and He + ND reactions at collision energies near K
Valentina Zhelyazkova, Fernanda B. V. Martins, Josef A. Agner +2
The energy dependence of the rates of the reactions between He and ammonia (NY, Y= {H,D}), forming NY, Y and He as well as NY, Y and He, and the corresponding…
Ion-molecule reactions below 1~K: Observation of a strong enhancement of the reaction rate of the ion-dipole reaction He+ CHF
Valentina Zhelyazkova, Fernanda B. V. Martins, Josef A. Agner +2
The reaction between He and CHF forming predominantly CH and CHF has been studied at collision energies between 0 and ~K in a me…
SI-traceable frequency dissemination at 1572.06 nm in a stabilized fiber network with ring topology
Dominik Husmann, Laurent-Guy Bernier, Mathieu Bertrand +18
Frequency dissemination in phase-stabilized optical fiber networks for metrological frequency comparisons and precision measurements are promising candidates to overcome the limita…
Precision Measurements in Few-Electron Molecules: The Ionization Energy of Metastable He and the First Rotational Interval of He
Luca Semeria, Paul Jansen, Gian-Marco Camenisch +3
Molecular helium represents a benchmark system for testing calculations on few-electron molecules. We report on the determination of the adiabatic ionization e…
Precision measurement of the ionization energy and quantum defects of 39K I
Michael Peper, Felix Helmrich, Jonas Butscher +4
We present absolute-frequency measurements in ultracold 39K samples of the transitions from the ground state to np Rydberg states. A global nonlinear regression of the np1/2 and np…
Fluorescence-lifetime-limited trapping of Rydberg helium atoms on a chip
Valentina Zhelyazkova, Matija Žeško, Hansjürg Schmutz +2
Metastable (1s)(2s) helium atoms produced in a supersonic beam were excited to Rydberg-Stark states (with in the range) in a cryogenic environment and sub…
New method to study ion-molecule reactions at low temperatures and application to the H + H H + H reaction
Pitt Allmendinger, Johannes Deiglmayr, Otto Schullian +4
Studies of ion-molecule reactions at low temperatures are difficult because stray electric fields in the reaction volume affect the kinetic energy of charged reaction partners. We…
Infrared spectroscopy of molecular ions in selected rotational and spin-orbit states
Ugo Jacovella, Josef A. Agner, Hansjürg Schmutz +2
First results are presented obtained with an experimental setup developed to record IR spectra of rotationally state-selected ions. The method we use is a state-selective version o…
Vacuum-ultraviolet frequency-modulation spectroscopy
Urs Hollenstein, Hansjürg Schmutz, Josef Anton Agner +2
Frequency-modulation (FM) spectroscopy has been extended to the vacuum-ultraviolet (VUV) range of the electromagnetic spectrum. Coherent VUV laser radiation is produced by resonanc…
Rydberg states of helium in electric and magnetic fields of arbitrary relative orientation
Ondřej Tkáč, Matija Žeško, Josef Anton Agner +2
A spectroscopic study of Rydberg states of helium ( = 30 and 45) in magnetic, electric and combined magnetic and electric fields with arbitrary relative orientations of the fiel…
Measuring the dispersive frequency shift of a rectangular microwave cavity induced by an ensemble of Rydberg atoms
M. Stammeier, S. Garcia, T. Thiele +5
In recent years the interest in studying interactions of Rydberg atoms or ensembles thereof with optical and microwave frequency fields has steadily increased, both in the context…
Slow and velocity-tunable beams of metastable He by multistage Zeeman deceleration
Michael Motsch, Paul Jansen, Josef A. Agner +2
Metastable helium molecules (He) have been generated by striking a discharge in a supersonic expansion of helium gas from a pulsed valve. When operating the pulsed valve at r…
Multistage Zeeman deceleration of metastable neon
Alex W. Wiederkehr, Michael Motsch, Stephen D. Hogan +5
A supersonic beam of metastable neon atoms has been decelerated by exploiting the interaction between the magnetic moment of the atoms and time-dependent inhomogeneous magnetic fie…