Related papers: The hyperfine structure of the hydrogen molecular …
The low-energy theorem for the forward Compton scattering is generalized to the case of an arbitrary target spin. The generalization is used to calculate the corresponding contribution to the deuterium hyperfine structure. The…
Highly accurate results from frequency measurements on neutral hydrogen molecules H_2, HD and D_2 as well as the HD^+ ion can be interpreted in terms of constraints on possible fifth-force interactions. Where the hydrogen atom is a probe…
Because molecules can have their orientation locked when embedded into a solid rare-gas matrix, their hyperfine structure is strongly perturbed relative to the freely rotating molecule. The addition of an electric field further perturbs the…
We report a calculation of the fine structure splitting in light helium-like atoms, which accounts for all quantum electrodynamical effects up to order \alpha^5 Ry. For the helium atom, we resolve the previously reported disagreement…
A hydrogen-like atom consisting of a positive muon and an electron is known as muonium. It is a near-ideal two-body system for a precision test of bound-state theory and fundamental symmetries. The MuSEUM collaboration performed a new…
The one-loop nuclear structure corrections of order (Z alpha)^5 to the Lamb shift and hyperfine splitting of the deuterium are calculated. The contribution of the deuteron structure effects to the isotope shift (ep)-(ed), (mu p)-(mu d) in…
Possibility of observing the Mott momentum in the distribution of the deuterons produced in the process $p + n \to d + \gamma$, in the first stage of a nuclear reaction is presented. The correlation of a hard photon with a deuteron allows…
Numerous few-electron atomic systems are considered which can be used effectively for observing a potential variation of the fine-structure constant $\alpha$ and the electron-proton mass ratio $m_e/m_p$. We examine optical magnetic dipole…
We review the present understanding of the spin structure of protons and neutrons, the fundamental building blocks of nuclei collectively known as nucleons. The field of nucleon spin provides a critical window for testing Quantum…
We calculate the atomic structure of hydrogen and helium, atoms and molecules in an intense magnetic field, analytically and numerically with a judiciously chosen basis.
The hyperfine structure of bound electrons in hydrogen-like ions is considered with corrections to the energy levels due to vacuum polarization (VP). Corrections to the wave function as well as the magnetic potential are determined for both…
A measurement of the hyperfine structure of antihydrogen promises one of the best tests of CPT symmetry. We describe an experiment planned at the Antiproton Decelerator of CERN to measure this quantity in a beam of slow antihydrogen atoms.
Atomic spectroscopy is used to search for the space-time variation of fundamental constants which may be due to an interaction with scalar and pseudo-scalar (axion) dark matter. In this letter, we study the effects which are produced by the…
The hyperfine structure (hfs) of electron levels of $^{238}_{92}$U ions with the nucleus excited in the low-lying rotational $2^+$ state with an energy $E_{2^+} = 44.91$ keV is investigated. In hydrogenlike uranium, the hfs splitting for…
The rovibrational transition frequencies of molecular hydrogen ions (MHI) can be accurately computed using ab initio nonrelativistic quantum electrodynamics. A subset of the fundamental constants are required input. We analyze how, once…
Precision calculations of the fine and hyperfine structure of muonic atoms are performed in a relativistic approach and results for muonic 205 Bi, 147 Sm, and 89 Zr are presented. The hyperfine structure due to magnetic dipole and electric…
The quantum mechanics of two-electron systems is reviewed, starting with the ground state of the helium atom and helium-like ions, with central charge $Z\ge 2$. For Z=1, demonstrating the stability of the negative hydrogen ion, H$^-$,…
Since the early days of quantum mechanics hydrogen, as the simplest of all atoms, has been studied or used to investigate new physics. In parallel, this knowledge leads to different applications, e.g. a spin filter to separate metastable…
We have investigated the correction to the hyperfine structure of heavy multicharged ions, which is connected with the nuclear-polarization effect caused by the unpaired bound electron. Numerical calculations are performed for hydrogenlike…
The mechanism of deuteron production in heavy-ion collisions is shown to have a significant impact on the shape of the modified combinants of their multiplicity distribution. In light of this observation, an experimental study is proposed…