256 citations · 1.4k across the 20 of their papers we have counts for
11 papers · 1 filter
Constraints on exotic spin-dependent interactions between electrons from helium fine-structure spectroscopy
Filip Ficek, Derek F. Jackson Kimball, Mikhail Kozlov +3
Agreement between theoretical calculations of atomic structure and spectroscopic measurements is used to constrain possible contribution of exotic spin-dependent interactions betwe…
Search for the effect of massive bodies on atomic spectra and constraints on Yukawa-type interactions of scalar particles
N. Leefer, A. Gerhardus, D. Budker +2
We propose a new method to search for hypothetical scalar particles that have feeble interactions with Standard-Model particles. In the presence of massive bodies, these interactio…
Investigation of two-frequency Paul traps for antihydrogen production
Nathan Leefer, Kai Krimmel, William Bertsche +5
Radio-frequency (rf) Paul traps operated with multifrequency rf trapping potentials provide the ability to independently confine charged particle species with widely different char…
Search for ultralight scalar dark matter with atomic spectroscopy
Ken Van Tilburg, Nathan Leefer, Lykourgos Bougas +1
We report new limits on ultralight scalar dark matter (DM) with dilaton-like couplings to photons that can induce oscillations in the fine-structure constant alpha. Atomic dysprosi…
Towards a new measurement of parity violation in dysprosium
N. Leefer, L. Bougas, D. Antypas +1
The dysprosium parity violation experiment concluded nearly 17 years ago with an upper limit on weak interaction induced mixing of nearly degenerate, opposite parity states in atom…
Transverse laser cooling of a thermal atomic beam of dysprosium
N. Leefer, A. Cingöz, B. Gerber-Siff +3
A thermal atomic beam of dysprosium (Dy) atoms is cooled using the transition at 421 nm. The cooling is done via a standing light wave ort…