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Updated: Nov 19, 2025

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
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Measuring the α-particle charge radius with muonic helium-4 ions

Julian J Krauth1,2,3, Karsten Schuhmann4,5, Marwan Abdou Ahmed6

  • 1Max Planck Institute of Quantum Optics, Garching, Germany. j.krauth@vu.nl.

Nature
|January 28, 2021
PubMed
Summary

Precise spectroscopy of muonic helium-4 ions determined the alpha particle's charge radius. This measurement offers a new benchmark for nuclear physics theories and constrains beyond-standard-model physics.

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