Speaker
Description
The current status of tests of quantum electrodynamics with heavy ions is reviewed. The theoretical predictions for the Lamb shift and the hyperfine splitting in heavy ions are compared with available experimental data. Recent achievements and future prospects in studies of the g factor with highly charged ions are also reported. These studies can provide precise determination of fundamental constants and tests of QED within and beyond the Furry picture at strong-coupling regime. Recent theoretical results on the pair-creation probabilities in low-energy heavy-ion collisions are presented. Special attention is paid to tests of QED in supercritical regime. It is known that in slow collisions of two bare nuclei with the total charge larger than the critical value, Z_c >173, the initially neutral vacuum can spontaneously decay into the charged vacuum and two positrons. Detection of the spontaneous emission of positrons would be the direct evidence of this fundamental phenomenon. It is shown that the vacuum decay can be observed via impact-sensitive measurements of pair-production probabilities [1].
[1] I. A. Maltsev, V. M. Shabaev, R. V. Popov et al., arXiv:1903.08546.