g Factor of Boronlike Tin.

Area of Science:

• Atomic Physics
• Quantum Electrodynamics (QED)
• High-Precision Measurements

Background:

• Previous high-precision g-factor measurements were limited to lighter ions, such as argon-40.
• Understanding g factors in heavy, highly charged ions is crucial for testing fundamental theories.

Purpose of the Study:

• To perform the first high-precision measurement of the g factor for a heavy boronlike ion, specifically tin-118.
• To test the accuracy of ab initio theoretical calculations for many-electron systems.
• To explore the potential for determining fundamental constants like the fine-structure constant.

Main Methods:

• Utilized the Alphatrap experiment for the measurement.
• Achieved a measurement uncertainty of 0.5 parts per billion (ppb) for the g factor.

Main Results:

• The measured g factor of boronlike ^{118}Sn^{45+} is 0.6447038265(4).
• This result shows excellent agreement with state-of-the-art ab initio theory calculations, which predicted 0.6447029(8).
• The measurement extends high-precision tests of QED and many-electron interactions to higher atomic numbers (Z).

Conclusions:

• The study successfully measured the g factor of a heavy boronlike ion with unprecedented precision.
• The findings validate theoretical models for complex atomic systems and QED.
• The results pave the way for independent determination of the fine-structure constant by combining with other measurements.