Orateur
Prof.
Paul Indelicato
(CNRS)
Description
We have obtained a very accurate proton charge distribution radius by measuring the Lamb shift in the 2s level of muonic hydrogen[1]. The value we found, while roughly 10 times more accurate than the one derived from either hydrogen spectroscopy or electron-proton elastic scattering, is 5 standard deviations away. I will show the results of the experiment, the latest theoretical evaluations and discuss the implications of such a large disagreement.
[1] The size of the proton, R. Pohl, et al. Nature 466, 213-216 (2010).
Author
Prof.
Paul Indelicato
(CNRS)