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Precise measurement of Hyper Fine Structure of positronium using sub-THz light

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 نشر من قبل Shoji Asai
 تاريخ النشر 2010
  مجال البحث فيزياء
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Positronium is an ideal system for the research of the QED, especially for the QED in bound state. The discrepancy of 3.9sigma is found recently between the measured HFS values and the QED prediction ($O(alpha^3)$). It might be due to the contribution of the unknown new physics or the systematic problems in the previous all measurements. We propose new method to measure HFS precisely and directly. A gyrotron, a novel sub-THz light source is used with a high-finesse Fabry-Perot 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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