相关论文: Quantum electrodynamic calculation of the hyperfin…
We study the $\alpha + \alpha + {}^{3}$He cluster structure of ${}^{11}$C within the microscopic cluster model. The calculations essentially reproduce the energy spectra for both negative and positive parity states, particularly the…
RaOCH$_3$ molecule is one of the most sensitive systems for the electron electric dipole moment ($e$EDM) searches. Its hyperfine and $K-$doubling structure in the external electric field is of key importance for preparing and interpreting…
An improved hyperspherical harmonic method for the quantum three-body problem is presented to separate three rotational degrees of freedom completely from the internal ones. In this method, the Schr\"{o}dinger equation of three-body problem…
Quantum electrodynamics has been the first theory to emerge from the ideas of regularization and renormalization, and the coupling of the fermions to the virtual excitations of the electromagnetic field. Today, bound-state quantum…
The off-diagonal hyperfine interaction between the 6p1/2 and 6p3/2 states in 133Cs is evaluated in third-order MBPT giving 37.3 Hz and 48.3 Hz, respectively, for second-order energies of the 6p3/2 F=3 and F=4 levels. This result is a factor…
Corrections of orders $\alpha^5$ and $\alpha^6$ are calculated in the fine structure interval $\Delta E^{fs}=E(2P_{3/2})-E(2P_{1/2})$ and in the hyperfine structure of the energy levels $2P_{1/2}$ and $2P_{3/2}$ in muonic hydrogen. The…
The fine structure constant $\alpha$ has a particular status in physics. Its precise determination is required to test the quantum electrodynamics (QED) theory. The constant $\alpha$ is also a keystone for the determination of other…
A general computational scheme for the (non-relativistic) Bethe logarithm is developed opening the route to `routine' evaluation of the leading-order quantum electrodynamics correction (QED) relevant for spectroscopic applications for small…
A new method for studying the many-body response functions is elaborated and first applied to the $^3$He longitudinal response. An integral transform of the response function is calculated from the bound-state-type equations for several…
The present knowledge of Lamb shift, fine-, and hyperfine structure of the 2S and 2P states in muonic helium-3 ions is reviewed in anticipation of the results of a first measurement of several $\mathrm{2S\rightarrow2P}$ transition…
The quantum electrodynamics formalism to treat the interelectronic-interaction correction of first order in $1/Z$ to the two-electron part of the nuclear recoil effect on binding energies in atoms and ions is developed. The nonperturbative…
A realistic microscopic calculation of the unpolarized quark Generalized Parton Distribution (GPD) $H_q^3$ of the $^3He$ nucleus is presented. In Impulse Approximation, $H_q^3$ is obtained as a convolution between the GPD of the internal…
We present a systematic study of the high-pressure FeSe phase performed by means of the first-principle electronic structure calculations. Basing on available experimental information about the unit cell geometry we calculate the band…
The structure functions of real and virtual photons are derived from cross section measurements of the reaction e^+e^ -> e^+e^- + hadrons at LEP. The reaction is studied at \sqrt{s} ~ 91 GeV with the L3 detector. One of the final state…
We determine the pressure of a cold and dense electron gas to a nearly complete next-to-next-to-next-to-leading order (N$^3$LO) in the fine-structure constant $\alpha_e$, utilizing a new result for the two-loop photon self-energy from a…
The relativistic wave function of $^3$He nucleus is calculated in the framework of Light-Front Dynamics. It is determined by 32 spin-isospin components, each of which depends on five scalar variables. For NN interaction, the one-boson…
We present new trial wave-functions which include 3-body correlations into the backflow coordinates and a 4-body symmetric potential. We show that our wavefunctions lower the energy enough to stabilize the ground state energies of normal…
In this Letter we present a field-theoretic formulation for describing non-ideal quantum electrodynamic effects. It generalizes its ideal counterpart and is valid in the non-ideal domain. We compute some non-ideal elementary processes both…
The hyperspherical harmonics (HH) provide a complete basis for the expansion of atomic wave functions, but even for two particles the number of harmonics for a given order is not trivial and, as the number of electrons increases, this…
Recent trends of ab initio studies and progress in methodologies for electronic structure calculations of strongly correlated electron systems are discussed. The interest for developing efficient methods is motivated by recent discoveries…