Antiproton–to–electron mass ratio determined by two-photon laser spectroscopy of antiprotonic helium atoms
1 Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany
2 Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
3 Wigner Research Center of Physics, H-1525 Budapest, Hungary
4 Paul Scherrer Institut, CH-5232 Villigen, Switzerland
5 Stefan Meyer Institut für Subatomare Physik, Boltzmanngasse 3, Vienna 1090, Austria
6 Dipartimento di Ingegneria dell’Informazione, Università di Brescia and Istituto Nazionale di Fisica Nucleare, Gruppo Collegato di Brescia, I-25133 Brescia, Italy
a e-mail: Anna.Soter@mpq.mpg.de
Published online: 20 March 2014
The ASACUSA collaboration of CERN has recently carried out two-photon laser spectroscopy of antiprotonic helium atoms. Three transition frequencies were determined with fractional precisions of 2.3–5 parts in 109. By comparing the results with three-body QED calculations, the antiproton-to-electron mass ratio was determined as 1836.1526736(23).
© Owned by the authors, published by EDP Sciences, 2014
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