Speaker
Description
In the last few years, spectroscopy of molecular hydrogen ions (MHI) contributed for the first time in the adjustment of fundamental constants and in establishing bounds on beyond-standard-model interactions. Ongoing improvements and diversification of experimental methods require advancing further the theoretical description of MHIs. One way in which this may be achieved consists in combining results from nonrelativistic and relativistic QED approaches.
This was done to improve the calculation of the bound-electron $g$-factor [1], which was recently measured for the HD$^+$ rovibrational ground state in a single-ion Penning-trap experiment [2].
Regarding the energy levels, the NRQED approach is used to calculate $m\alpha^6$-order relativistic and relativistic-recoil corrections within a full (nonadiabatic) description of the three-body system [3-4]. On the other hand, the relativistic approach is a way forward for the calculation of the one-loop self-energy correction, which is currently the largest source of uncertainty, and where recent progress was achieved in the hydrogen-like atom case [5-6].
Results and perspectives in these two areas of theory will be discussed.
[1] O. Kullie, H.D. Nogueira, J.-Ph. Karr, Phys. Rev. A 112, 052813 (2025).
[2] C.M. König et al., arXiv:2602.20750, Phys. Rev. Lett., to appear.
[3] V.I. Korobov, Phys. Rev. A 112, 022808 and 022813 (2025).
[4] V.I. Korobov, J.-Ph. Karr, Z.-X. Zhong, Mol. Phys. e2563023 (2025).
[5] V.A. Yerokhin, Z. Harman, C.H. Keitel, Phys. Rev. A 111, 012802 (2025).
[6] D. Ferenc, M. Salman, T. Saue, Phys. Rev. A 111, L040802 (2025).