You are here

Nuclear structure effects in light muonic atoms and proton radius puzzle

ECT*- TIFPA seminar

Chen Ji

08 Sep 2015 - 14:30
Villa Tambosi 2nd Floor, Seminar Room

The proton radius extracted from recent high-precision measurements of the Lamb shift in muonic hydrogen disagrees significantly with the measurements from electronic hydrogen spectroscopy or electron-proton elastic scattering. Intrigued by the proton radius puzzle, new measurements of the Lamb shift in other light muonic atoms will be performed at PSI. These measurements aim to extract the nuclear charge radius with extremely high accuracies, limited by the uncertainty in the nuclear polarizability corrections. 
Nuclear polarizability are QCD effects that contribute to the Lamb shifts in muonic atoms. They need to be provided by theory with high accuracy. I will talk about how we perform ab-initio calculations of such nuclear structure effects using state-of-the-art nuclear Hamiltonians combined with hyperspherical harmonics methods, with a precision that satisfies the experimental requirement. I will present results for muonic deuterium and muonic 4He ion, and discuss the uncertainties from both atomic and nuclear physics. I will then discuss the extension to muonic 3He ion and muonic tritium. Such systems with unequal proton/neutron numbers may provide additional information for understanding the proton radius puzzle.