Muonic Atom Spectroscopy and the Proton Radius Puzzle

by Dr Julian Krauth (MPQ Garching/JSU Mainz (Germany))

Monday May 8, 2017, 9:00 AM → 10:00 AM Europe/Zurich

H51 (HIT)

In 2010 the CREMA collaboration measured the rms charge radius of the proton via laser spectroscopy of the 2S->2P Lamb shift in muonic hydrogen [1, 2]. Recently, the charge radius of the deuteron was determined [3]. Both measurements yield very precise charge radii but both values result 5 standard deviations away from the expected values, given by CODATA [4]. These discrepancies are known as the proton radius puzzle. In my talk I will introduce the different methods used to extract nuclear charge radii and explain more in detail our Lamb shift experiment and what is called the proton radius puzzle. Furthermore an outlook towards our upcoming results from the muonic helium measurements and their impact on the puzzle will be given. [1] R. Pohl et al., Nature 466, 213 (2010) [2] A. Antognini et al., Science 339, 417 (2013) [3] R. Pohl et al., Science 353, 6300 (2016) [4] P.J. Mohr et al., Review of Modern Physics 88, 035009 (2016)

Slides Krauth_20170508.pdf