P. Jansen

activity

20022020

most citedRobust Constraint on a Drifting Proton-to-Electron Mass Ratio at z=0.89 from Methanol Observation at Three Radio Telescopes

100 citations · 523 across the 14 of their papers we have counts for

collaborators

16 papers

physics.atom-ph2020★ 26 cited

Precision Measurements in Few-Electron Molecules: The Ionization Energy of Metastable $^{4}$ He $_{2}$ and the First Rotational Interval of $^{4}$ He $_{2}^{+}$

Luca Semeria, Paul Jansen, Gian-Marco Camenisch +3

Molecular helium represents a benchmark system for testing $ab initio$ calculations on few-electron molecules. We report on the determination of the adiabatic ionization e…

physics.chem-ph2017★ 15 cited

Precision measurement of the rotational energy-level structure of the three-electron molecule He $_{2}^{+}$

Luca Semeria, Paul Jansen, Frédéric Merkt

The term values of all rotational levels of the $^{4}$ He $_{2}^{+} X^{+}^{2} Σ_{u}^{+} (ν^{+} = 0)$ ground vibronic state with rotational quantum number $N^{+} \leq 19$ have been determined with an…

physics.chem-ph2017★ 15 cited

High-resolution spectroscopy of He $_{2}^{+}$ using Rydberg-series extrapolation and Zeeman-decelerated supersonic beams of metastable He $_{2}$

Paul Jansen, Luca Semeria, Frédéric Merkt

Recently, high-resolution spectroscopy of slow beams of metastable helium molecules (He $_{2}^{*}$ ) generated by multistage Zeeman deceleration was used in combination with Rydberg-seri…

physics.chem-ph2016★ 54 cited

A molecular fountain

Cunfeng Cheng, Aernout P. P. van der Poel, Paul Jansen +4

The resolution of any spectroscopic or interferometric experiment is ultimately limited by the total time a particle is interrogated. We here demonstrate the first molecular founta…

physics.atom-ph2016★ 67 cited

Precision measurement of the ionization energy of Cs I

Johannes Deiglmayr, Holger Herburger, Heiner Saßmannshausen +3

We present absolute-frequency measurements for the transitions from the 6s $_{1/2}$ ground state of $^{133}$ Cs to $n$ p $_{1/2}$ and $n$ p $_{3/2}$ Rydberg states. The transition freque…

physics.chem-ph2014★ 38 cited

Slow and velocity-tunable beams of metastable He $_{2}$ by multistage Zeeman deceleration

Michael Motsch, Paul Jansen, Josef A. Agner +2

Metastable helium molecules (He $_{2}^{*}$ ) 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…

Precision Measurements in Few-Electron Molecules: The Ionization Energy of Metastable 4He2​ and the First Rotational Interval of 4He2​+

Precision measurement of the rotational energy-level structure of the three-electron molecule He2+​

High-resolution spectroscopy of He2+​ using Rydberg-series extrapolation and Zeeman-decelerated supersonic beams of metastable He2​