Precision Mass Spectroscopy of the Antiproton and Proton Using Simultaneously Trapped Particles

G. Gabrielse, A. Khabbaz, D. S. Hall, C. Heimann, H. Kalinowsky, and W. Jhe
Phys. Rev. Lett. 82, 3198 – Published 19 April 1999
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This last of a series of three measurements improves the comparison of antiproton (p¯) and proton (p) by almost a factor of 106 over earlier exotic atom measurements, and is the most precise CPT test with baryons by a similar large factor. Measuring the cyclotron frequencies of a simultaneously trapped p¯ and H ion establishes that the ratio of q/m for p¯ and p is 0.99999999991±0.00000000009, more than 10 times the accuracy over our previous measurement. This 9×1011 comparison makes the first use of simultaneously trapped particles for sub-ppb spectroscopy.

  • Received 10 November 1998


©1999 American Physical Society

Authors & Affiliations

G. Gabrielse, A. Khabbaz, and D. S. Hall*

  • Department of Physics, Harvard University, Cambridge, Massachusetts 02138

C. Heimann and H. Kalinowsky

  • Institut für Strahlen- und Kernphysik, University of Bonn, 53115 Bonn, Germany

W. Jhe

  • Department of Physics, Seoul National University, 151-742 Seoul, Korea

  • *Current address: CB440, JILA, Boulder, Colorado.

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Vol. 82, Iss. 16 — 19 April 1999

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