Pohl, Randolf Amaro, Fernando D. Antognini, Aldo Biraben, François Cardoso, João M. R. Covita, Daniel S. Dax, Andreas Dhawan, Satish Fernandes, Luis M. P. Giesen, Adolf Graf, Thomas Hänsch, Theodor W. Indelicato, Paul Julien, Lucile Kao, Cheng-Yang Knowles, Paul E. Bigot, Eric-Olivier Le Liu, Yi-Wei Lopes, José A. M. Ludhova, Livia Monteiro, Cristina M. B. Mulhauser, Françoise Nebel, Tobias Nez, François Rabinowitz, Paul Santos, Joaquim M. F. dos Schaller, Lukas A. Schuhmann, Karsten Schwob, Catherine Taqqu, David Veloso, João F. C. A. Kottmann, Franz 2011 We have recently measured the 2<i>S</i>_1/2⁼¹ − 2<i>P</i>_3/2 ⁼ ² energy splitting in the muonic hydrogen atom <i>μ</i>p to be 49881.88 (76) GHz. Using recent QED calculations of the fine-, hyperfine, QED and finite size contributions we obtain a root-mean-square proton charge radius of <i>r</i>_p = 0.84184 (67) fm. This value is ten times more precise, but 5 standard deviations smaller, than the 2006 CODATA value of <i>r</i>_p = 0.8768 (69) fm. The source of this discrepancy is unknown. Using the precise measurements of the 1S-2S transition in regular hydrogen and deuterium and our value of <i>r</i>_p we obtain improved values of the Rydberg constant, <i>R</i>_∞ = 10973731.568160 (16) m⁻¹and the rms charge radius of the deuteron <i>r</i>_d = 2.12809 (31) fm. application/pdf https://folia.unifr.ch/global/documents/301781 https://folia.unifr.ch/documents/301781/files/muh_spd.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1088/1742-6596/264/1/012008 info:eu-repo/semantics/openAccess License undefined Journal of Physics: Conference Series. - 2011, vol. 264, no. 1, p. 012008 info:eu-repo/classification/udc/53 The size of the proton and the deuteron http://purl.org/coar/resource_type/c_6501