TY - JOUR
T1 - Experiment for the first direct measurement of the hyperfine splitting of positronium
AU - Miyazaki, A.
AU - Suehara, T.
AU - Ishida, A.
AU - Namba, T.
AU - Asai, S.
AU - Kobayashi, T.
AU - Saito, H.
AU - Yoshida, M.
AU - Idehara, T.
AU - Ogawa, I.
AU - Urushizaki, Y.
AU - Sabchevski, S.
PY - 2010
Y1 - 2010
N2 - Positronium is an ideal system for the research of the bound state QED. The hyperfine splitting of positronium (Ps-HFS: about 203 GHz) is a good tool to test QED and also sensitive to new physics beyond the Standard Model via a quantum oscillation between an ortho-Ps and a virtual photon. Previous experimental results show 3.9 σ (15 ppm) discrepancy from the QED calculation. All previous experiments used an indirect method with static magnetic field to cause Zeeman splitting (a few GHz) between triplet states of ortho-Ps, from which the HFS value was derived. One possible systematic error source of the indirect method is non-uniformity of the static magnetic field. We are developing a new direct Ps-HFS measurement system without static magnetic field. In this measurement we use a gyrotron, a novel sub-THz light source, with a high-finesse Fabry-Pérot cavity to obtain enough radiation power at 203 GHz. The present status of the optimization studies and current design of the experiment are described.
AB - Positronium is an ideal system for the research of the bound state QED. The hyperfine splitting of positronium (Ps-HFS: about 203 GHz) is a good tool to test QED and also sensitive to new physics beyond the Standard Model via a quantum oscillation between an ortho-Ps and a virtual photon. Previous experimental results show 3.9 σ (15 ppm) discrepancy from the QED calculation. All previous experiments used an indirect method with static magnetic field to cause Zeeman splitting (a few GHz) between triplet states of ortho-Ps, from which the HFS value was derived. One possible systematic error source of the indirect method is non-uniformity of the static magnetic field. We are developing a new direct Ps-HFS measurement system without static magnetic field. In this measurement we use a gyrotron, a novel sub-THz light source, with a high-finesse Fabry-Pérot cavity to obtain enough radiation power at 203 GHz. The present status of the optimization studies and current design of the experiment are described.
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U2 - 10.1088/1742-6596/225/1/012037
DO - 10.1088/1742-6596/225/1/012037
M3 - Article
AN - SCOPUS:78651097249
SN - 1742-6588
VL - 225
JO - Journal of Physics: Conference Series
JF - Journal of Physics: Conference Series
M1 - 012037
ER -