The Rydberg constant and proton size from atomic hydrogen

  title={The Rydberg constant and proton size from atomic hydrogen},
  author={Axel Beyer and Lothar Maisenbacher and Arthur Matveev and Randolf Pohl and Ksenia Yu Khabarova and Alexey Grinin and Tobias P. Lamour and Dylan C. Yost and Theodor W. H{\"a}nsch and Nikolai Kolachevsky and Thomas Udem},
  pages={79 - 85}
How big is the proton? The discrepancy between the size of the proton extracted from the spectroscopy of muonic hydrogen and the value obtained by averaging previous results for “regular” hydrogen has puzzled physicists for the past 7 years. Now, Beyer et al. shed light on this puzzle (see the Perspective by Vassen). The authors obtained the size of the proton using very accurate spectroscopic measurements of regular hydrogen. Unexpectedly, this value was inconsistent with the average value of… Expand

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