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arXiv · 1403.0312

First Millimeter-wave Spectroscopy of the Ground-state Positronium

A. Miyazaki·T. Yamazaki·T. Suehara·T. Namba·S. Asai·T. Kobayashi·H. Saito·Y. Tatematsu·I. Ogawa·T. Idehara
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Abstract

We report on the first measurement of the Breit-Wigner resonance of the transition from {\it ortho-}positronium to {\it para-}positronium. We have developed an optical system to accumulate a power of over 20 kW using a frequency-tunable gyrotron and a Fabry-P\'{e}rot cavity. This system opens a new era of millimeter-wave spectroscopy, and enables us to directly determine both the hyperfine interval and the decay width of {\it p-}Ps.

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A. Miyazaki, T. Yamazaki, T. Suehara, T. Namba, S. Asai, T. Kobayashi, H. Saito, Y. Tatematsu, I. Ogawa, T. Idehara. 2014-03-03. First Millimeter-wave Spectroscopy of the Ground-state Positronium. https://doi.org/10.1093/ptep/ptu181

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