Related papers: Precision Study of Positronium: Testing Bound Stat…
The similarities of hadrons and atoms motivate a study of the principles of QED bound states and of their applicability to QCD. The power series in $\alpha$ and $\log\alpha$ of the binding energy is reflected in the Fock expansion of the…
We review the equation of state of QCD matter at finite densities. We discuss the construction of the equation of state with net baryon number, electric charge, and strangeness using the results of lattice QCD simulations and hadron…
The quantum electrodynamics (QED) corrections are directly incorporated into the most accurate treatment of the correlation corrections for ions with complex electronic structure of interest to metrology and tests of fundamental physics. We…
A new relativistic method for calculation of positron binding to atoms is presented. The method combines a configuration interaction treatment of the valence electron and the positron with a many-body perturbation theory description of…
The method of NRQED is an adaptation of QED to bound systems. While it is fully equivalent to QED, it enables us to explore the QED bound states systematically as an expansion in the fine structure constant $\alpha$ and velocity ($\sim…
We use the S-matrix formalism of bound-state QED to study the photon-atom scattering. We find that the internal lines in Feynman diagrams which describing the propagation of off-shell bound electrons provide the off-shell amplitudes of…
Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic physics program at Jefferson Lab (JLab),…
Using a well-established effective interaction in a rainbow-ladder truncation model of QCD, we fix the remaining model parameter to the bottomonium ground-state spectrum in a covariant Bethe-Salpeter equation approach and find surprisingly…
There is considerable freedom in setting boundary conditions to perturbation theory at $t=\pm\infty$. The standard PQED and PQCD expansions are based on the (empty) perturbative vacuum. Since the true QCD ground state is expected to have a…
The subjects which are discussed in this Thesis include: the self energy of a bound electron and the spin-dependence of QED corrections in bound systems, convergence acceleration techniques, and resummation methods for divergent series with…
We report Dirac-Fock calculations of transition energies for kaonic neon (KNe). For the most intense line, the 7-6 transition, the calculated energy is 9450.28 eV, which includes a bound-state QED (BSQED) contribution of 12.66 eV. This is…
Lepto-nuclear colliders offer unique experimental opportunities to probe QCD in an extended medium. Of the many possibilities, three experiments are described here that are clearly feasible and of high scientific importance. First, a direct…
Heavy quarkonium is one of the most investigated probes of the medium produced in heavy-ion collisions. In the past few years progress has been made in the description of its in-medium dynamics from QCD. Non-relativistic EFTs in particular…
Bound upsilon states and their decays provide a unique laboratory for testing QCD, LQCD, and quarkonium potential models. I review recent results, some of which are significant improvements in precision over previous measurements and others…
PAX (antiProtonic Atom X-ray spectroscopy) is a new experiment with the aim to test strong-field quantum electrodynamics (QED) effects by performing high-precision x-ray spectroscopy of antiprotonic atoms. By utilizing advanced…
Comparison of precision frequency measurements to quantum electrodynamics (QED) predictions for Rydberg states of hydrogen-like ions can yield information on values of fundamental constants and test theory. With the results of a calculation…
Recent progress in laser and x-ray spectroscopy of muonic atoms offers promising long-term possibilities at the intersection of atomic, nuclear and particle physics. In muonic hydrogen, laser spectroscopy measurements will determine the…
This paper presents an analysis of the positron capture by a neutron reaction, which is just the inverse of the well-known neutrino capture by a proton reaction. The effect of the QED radiative corrections is investigated. In particular,…
The bound-state QED approach is applied to calculations of the $2p_{3/2} \rightarrow 2s$ transition energies in He-, Li-, and Be-like uranium. For U$^{90+}$ and U$^{89+}$, standard perturbation theory for a single level is employed, while…
In Penning traps electromagnetic forces are used to confine charged particles under well-controlled conditions for virtually unlimited time. Sensitive detection methods have been developed to allow observation of single stored ions. Various…