Related papers: Two-loop QED corrections with closed fermion loops
Two-loop QED corrections with closed fermion loops are calculated for the 1s bound-electron g factor. Calculations are performed to all orders in the nuclear binding strength parameter Z\alpha (where Z is the nuclear charge and \alpha is…
Results of a calculation valid to all orders in the nuclear-strength parameter Z\alpha are presented for the two-loop Lamb shift, notably for the two-loop self-energy correction, for the ground and first excited states of ions with the…
The two-loop self-energy correction to the Lamb shift of hydrogen-like ions is calculated for the $1s$, $2s$, and $2p_{1/2}$ states and nuclear charge numbers $Z = 30$-$100$. The calculation is performed to all orders in the nuclear binding…
The two-loop self-energy correction is evaluated to all orders in Z alpha for the ground-state Lamb shift of H-like ions with Z >= 20, where Z is the nuclear charge number and alpha is the fine structure constant. The results obtained are…
We present ab initio calculations of one-electron quantum electrodynamical corrections to the second-order Zeeman splitting for the $1s_{1/2}$, $2s_{1/2}$, and $2p_{1/2}$ states in highly charged hydrogen-like ions. The self-energy…
A calculation of the one-loop self-energy and vacuum-polarization corrections to the hyperfine splitting of the 1s and 2s states in light H-like ions is carried out to all orders in the parameter Z \alpha. Using the known values for the Z…
The two-loop self-energy correction is evaluated to all orders in Z\alpha for the ground-state Lamb shift of H-like ions with Z >= 10, where Z is the nuclear charge number and \alpha is the fine structure constant. The results obtained are…
We commence the evaluation of the one- and two-loop binding corrections to the $g factor for an electron in a hydrogenlike system of order alpha^2 (Z alpha)^5 and consider diagrams with closed fermion loops. The one-loop vacuum-polarization…
Calculations of the two-loop electron self-energy for the $n = 1$ and $n = 2$ states of hydrogen-like ions are reported, performed to all orders in the nuclear binding strength parameter $Z\alpha$ (where $Z$ is the nuclear charge number and…
The two-loop self-energy correction to the ground state Lamb shift is calculated for hydrogen-like ions with the nuclear charge Z=10-30 without any expansion in the binding field of the nucleus. A calculational technique is reported for…
We present a complete calculation of the next-to-next-to-leading (NNLO) electroweak corrections involving closed fermion loops to the $e^+ e^- \to ZH$ process. This has been achieved by using a semi-numerical technique for the two-loop…
The two-loop self-energy correction to the bound-electron $g$-factor in hydrogenlike ions is investigated, taking into account the electron-nucleus interaction exactly. This all-order calculation is required to improve the total theoretical…
A calculation of two-electron QED effects to all orders in the nuclear binding strength parameter $Z\alpha$ is presented for the ground and $n = 2$ excited states of helium-like ions. After subtracting the first terms of the $Z\alpha$…
We calculate the one- and two-loop corrections of order alpha(Zalpha)^6 and alpha^2(Zalpha)^6 respectively, to the Lamb shift in hydrogen-like systems using the formalism of nonrelativistic quantum electrodynamics. We obtain general results…
A calculation valid to all orders in the nuclear-strength parameter is presented for the two-loop Lamb shift, notably for the two-loop self-energy correction, to the 2p-2s transition energies in heavy Li-like ions. The calculation removes…
A critical set of two-loop QED corrections to the $g$ factor of hydrogenlike ions is calculated without expansion in the nuclear binding field. These corrections are due to the polarization of the external magnetic field by the quantum…
We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…
A complete evaluation of the two-loop self-energy diagrams to all orders in Z\alpha is presented for the ground state of H-like ions with Z\ge 40.
We perform ab initio QED calculations of energy levels for the $n=1$ and $n=2$ states of He-like ions with the nuclear charge in the range $Z = 12$-100. The complete set of two-electron QED corrections is evaluated to all orders in the…
The Drell-Yan production of charged lepton pairs is one of the key processes measured at hadron colliders. The QCD corrections to the cross section are known to order $\alpha_s^2$ and electroweak corrections are known to order $\alpha$. The…