Related papers: Matter-positronium interaction: An exact diagonali…
Stark transitions and induced annihilation of antiproton in the collisions of antiprotonic helium ions (\bar{p}He^{+2})_{nl} with He atoms at very low energy (~ 10 K) are considered in the framework of quantum coupled-channels method taking…
A direct test of the CPT symmetry is performed for the electromagnetic decays of ortho-positronium using the J-PET tomograph. We present the precise measurement of the CPT-sensitive angular correlation entailing the positronium spin and the…
We used a torsion pendulum containing $\approx 10^{23}$ polarized electrons to search new interactions that couple to electron spin. We limit CP-violating interactions between the pendulum's electrons and unpolarized matter in the earth or…
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…
We report a measurement of the dynamical polarizability of dysprosium atoms in their electronic ground state at the optical wavelength of 1064 nm, which is of particular interest for laser trapping experiments. Our method is based on…
In our Galaxy, light antinuclei composed of antiprotons and antineutrons can be produced through high-energy cosmic-ray collisions with the interstellar medium or could also originate from the annihilation of dark-matter particles that have…
The OLYMPUS experiment measured the cross-section ratio of positron-proton elastic scattering relative to electron-proton elastic scattering to look for evidence of hard two-photon exchange. To make this measurement, the experiment…
Recent experimental progress in the field of cavity quantum electrodynamics allows to study the regime of strong interaction between quantized light and complex matter systems. Due to the coherent coupling between photons and matter-degrees…
We study the near threshold behavior of cross sections of low-energy antiproton scattering off the ground and excited states of positronium with zero total orbital momentum $L=0$. In our computational experiment, the existence of…
Hard photodisintegration of the deuteron has been extensively studied in order to understand the dynamics of the transition from hadronic to quark-gluon descriptions of the strong interaction. In this work, we discuss the extension of this…
The understanding of the origin of dark matter has great importance for cosmology and particle physics. Several interesting extensions of the standard model dealing with solution of this problem motivate the concept of hidden sectors…
We present first-principles approaches based on density functional theory for calculating positron states and annihilation characteristics in condensed matter. The treatment of the electron-positron correlation effects (the enhancement of…
Positron and electron cosmic rays provide a complementary way to study the galactic environment. The actual cosmic rays experiments, for instance PAMELA and HEAT, have presented very exciting results in this field. The observed positron…
A method is proposed for detecting positron-atom bound states by observing enhanced positron annihilation due to electronic Feshbach resonances at electron-volt energies. The method is applicable to a range of open-shell transition metal…
The 1%-accurate calculations of the van der Waals interaction between an atom and a cavity wall are performed in the separation region from 3 nm to 150 nm. The cases of metastable He${}^{\ast}$ and Na atoms near the metal, semiconductor or…
We prove two equilibrium properties of a system of interacting atoms in three or higher dimensional continuous space. (i) If the particles interact via pair potentials of a nonnegative Fourier transform, their self-organization into…
In this paper we present prospects for using the J-PET detector to search for discrete symmetries violations in a purely leptonic system of the positronium atom. We discuss tests of CP and CPT symmetries by means of ortho-positronium decays…
When polarized light is absorbed by an atom, the excited atomic system carries information about the initial polarization of light. For the light that carries an orbital angular momentum, or the twisted light, the polarization states are…
A proper theoretical description of electronic structure of the 3d orbitals in the metal centers of functional metalorganics is a challenging problem. In this letter, we apply density functional theory and an exact diagonalization method in…
The Classification of Polarization elements, the polarization affecting optical devices which have a Jones matrix representation, according to the types of eigenvectors they possess, is given a new visit through the Group-theoretical…