894 citations · 1.5k across the 20 of their papers we have counts for
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Optically Derived Radio-Frequency Benchmark in Methanol: A Sub-kHz Reference for Astrophysical Tests of Fundamental Physics
Frank M. J. Cozijn, Arthémise Altman, Alexandr S. Bogomolov +8
Methanol radio lines observed in space provide sensitive probes of whether the proton-to-electron mass ratio has changed over cosmic time, but such tests require laboratory rest fr…
Quasi-continuous sub-K strontium source without a high-finesse cavity stabilized laser
Sana Boughdachi, Benedikt Heizenreder, Ananya Sitaram +8
We demonstrate a quasi-continuous sub-K strontium source achieved without the use of a high-finesse cavity-locked laser. Our frequency reference is based on a dispersion-optimiz…
Extraction of spin-averaged rovibrational transition frequencies in HD for the determination of fundamental constants
Jean-Philippe Karr, Jeroen C. J. Koelemeij
We present a comprehensive analysis of all currently available high-accuracy frequency measurements of rotational and rovibrational transitions in the hydrogen molecular ion HD…
Proton-Electron Mass Ratio from Laser Spectroscopy of HD at the Part-Per-Trillion Level
Sayan Patra, M. Germann, J. -Ph. Karr +7
Accepted values of the masses of several subatomic particles have been under debate since recent measurements in Penning traps produced more precise yet incompatible results, imply…
Proton-electron mass ratio from HD revisited
Sayan Patra, J. -Ph. Karr, L. Hilico +3
We present a new derivation of the proton-electron mass ratio from the hydrogen molecular ion, HD. The derivation entails the adjustment of the mass ratio in highly precise the…
Hydrogen molecular ions for improved determination of fundamental constants
J. -Ph Karr, L Hilico, Jeroen Koelemeij +1
The possible use of high-resolution rovibrational spectroscopy of the hydrogen molecular ions H + 2 and HD + for an independent determination of several fundamental constants is an…
Probing QED and fundamental constants through laser spectroscopy of vibrational transitions in HD+
J. Biesheuvel, J. -Ph. Karr, L. Hilico +3
The simplest molecules in nature, molecular hydrogen ions in the form of H2+ and HD+, provide an important benchmark system for tests of quantum electrodynamics in complex forms of…
Physics beyond the Standard Model from hydrogen spectroscopy
Wim Ubachs, Jeroen C. J. Koelemeij, Kjeld S. E. Eikema +1
Spectroscopy of hydrogen can be used for a search into physics beyond the Standard Model. Differences between the absorption spectra of H as observed at high redshift and those…
Two-photon spectroscopy of trapped HD ions in the Lamb-Dicke regime
Vu Quang Tran, Jean-Philippe Karr, Albane Douillet +2
We study the feasibility of nearly-degenerate two-photon rovibrational spectroscopy in ensembles of trapped, sympathetically cooled hydrogen molecular ions using a resonance-enhanc…
Blackbody radiation shift of the 27Al+ 1S0 - 3P0 transition
T. Rosenband, W. M. Itano, P. O. Schmidt +4
The differential polarizability, due to near-infrared light at 1126 nm, of the 27Al+ 1S0 -> 3P0 clock transition is measured to be 4πε_0 x (1.6 +/- 0.5) x 10^{-31} m^3. This measur…
Precision Spectroscopy of Molecular Hydrogen Ions: Towards Frequency Metrology of Particle Masses
B. Roth, J. Koelemeij, S. Schiller +4
We describe the current status of high-precision ab initio calculations of the spectra of molecular hydrogen ions (H_2^+ and HD^+) and of two experiments for vibrational spectrosco…
Magneto-optical trap for metastable helium at 389 nm
J. C. J. Koelemeij, R. J. W. Stas, W. Hogervorst +1
We have constructed a magneto-optical trap (MOT) for metastable triplet helium atoms utilizing the 2 3S1 -> 3 3P2 line at 389 nm as the trapping and cooling transition. The far-red…