Precise measurement of positronium hyperfine splitting using the Zeeman effect

Abstract

Positronium is an ideal system for the research of the quantum electrodynamics (QED) in bound state. The hyperfine splitting (HFS) of positronium, ${\Delta }_{\mathrm{HFS}}$, gives a good test of the bound state calculations and probes new physics beyond the Standard Model. A new method of QED calculations has revealed the discrepancy by 15\,ppm (3.9$\sigma$) of ${\Delta }_{\mathrm{HFS}}$ between the QED prediction and the experimental average. There would be possibility of new physics or common systematic uncertainties in the previous all experiments. We describe a new experiment to reduce possible systematic uncertainties and will provide an independent check of the discrepancy. We are now taking data and the current result of ${\Delta }_{\mathrm{HFS}}=203.3951\pm 0.0024(stat.,12\mathrm{ppm})\pm 0.0019(sys.,9.5\mathrm{ppm})\mathrm{GHz}$ has been obtained so far. A measurement with a precision of $O$(ppm) is expected within a year.

8 pages, 8 figures, 2 tables, proceeding of LEAP2011, accepted by Hyperfine Interactions

References in corpus (6)

• Order alpha^7 ln(1/alpha) Contribution to Positronium Hyperfine Splitting
• First test of $O({\alpha }^2)$ correction of the orthopositronium decay rate
• O(alpha^3 ln alpha) corrections to muonium and positronium hyperfine splitting
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• Precision Measurement of Orthopositronium Decay Rate Using SiO_2 Powder
• New method of precise measurement of positronium hyperfine splitting

Cited by in corpus (5)

• Positronium Physics and Biomedical Applications
• Three-photon-annihilation contributions to positronium energies at order $m{\alpha }^7$
• Positronium hyperfine splitting at order $m{\alpha }^7$: light-by-light scattering in the two-photon-exchange channel
• Positronium energy levels at order $m{\alpha }^7$: light-by-light scattering in the two-photon-annihilation channel
• Positronium energy levels at order $m{\alpha }^7$: Product contributions in the two-photon-annihilation channel