The size of the proton

  title={The size of the proton},
  author={R. Pohl and A. Antognini and F. Nez and F. Amaro and F. Biraben and J. Cardoso and D. Covita and A. Dax and S. Dhawan and L. Fernandes and A. Giesen and T. Graf and T. H{\"a}nsch and P. Indelicato and L. Julien and Cheng-Yang Kao and P. Knowles and E. Bigot and Yi-Wei Liu and J. Lopes and L. Ludhova and C. Monteiro and F. Mulhauser and T. Nebel and P. Rabinowitz and J. D. Santos and L. Schaller and K. Schuhmann and C. Schwob and D. Taqqu and J. Veloso and F. Kottmann},
The proton is the primary building block of the visible Universe, but many of its properties—such as its charge radius and its anomalous magnetic moment—are not well understood. The root-mean-square charge radius, rp, has been determined with an accuracy of 2 per cent (at best) by electron–proton scattering experiments. The present most accurate value of rp (with an uncertainty of 1 per cent) is given by the CODATA compilation of physical constants. This value is based mainly on precision… Expand

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