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Updated: Feb 14, 2026
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Quantitative Analysis of Vacuum Induction Melting by Laser-induced Breakdown Spectroscopy
Published on: June 10, 2019
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Recent progress of laser spectroscopy experiments on antiprotonic helium
1Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany Masaki.Hori@mpq.mpg.de.
Summary
Researchers precisely measured the antiproton-to-electron mass ratio using laser spectroscopy on antiprotonic helium atoms. This experiment confirms the ratio
Area of Science:
- Atomic Physics
- Quantum Electrodynamics
- Particle Physics
Background:
- The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA) collaboration investigates antiprotonic helium atoms.
- Laser spectroscopy techniques are crucial for high-precision measurements in atomic physics.
Purpose of the Study:
- To precisely determine the antiproton-to-electron mass ratio.
- To test fundamental theories of quantum electrodynamics (QED).
Main Methods:
- Utilizing two-photon and single-photon laser spectroscopy on antiprotonic helium atoms.
- Employing buffer-gas cooling to enhance spectral resolution.
- Comparing experimental results with advanced three-body QED calculations.
Main Results:
- Achieved fractional precision of 2.3-5 parts in 10^9 for atomic transition frequencies.
- Determined the antiproton-to-electron mass ratio with a precision of 8x10^-10.
- Experimental results align with theoretical predictions from QED.
Conclusions:
- High-precision laser spectroscopy of antiprotonic helium provides a stringent test of QED.
- The measured antiproton-to-electron mass ratio is consistent with the proton-to-electron mass ratio.
- Future experiments with enhanced antiproton beams (e.g., from ELENA) promise even greater precision.
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