Related papers: Matter-positronium interaction: An exact diagonali…
Measurements of polarized neutron--polarized $^3$He scattering are reported. The target consisted of cryogenically-polarized solid $^3$He, thickness 0.04 atom/b and polarization 40%. The longitudinal and transverse total cross-section…
We reexamine in detail the various processes undergone by positrons in the ISM from their birth to their annihilation using the most recent results of positron interaction cross sections with H, H2 and He. The positrons' lives are divided…
Entanglement between two electrons belonging to an auto-ionization system and a neighbor two-level atom produced by the dipole-dipole interaction is studied. The entanglement is quantified using the quadratic negativity of a bipartite…
Measuring the Doppler broadening of the positron annihilation radiation or the angular correlation between the two annihilation gamma quanta reflects the momentum distribution of electrons seen by positrons in the material.Vacancy-type…
Neutron rich He nuclei have been investigated using relativistic mean field approach in co-ordinate space. Elastic partial scattering cross sections for proton scattering in inverse kinematics have been calculated using the theoretically…
Properties of some few-body systems which include one positively charged muon $\mu^{+}$ and two electrons $e^{-}$ are discussed. In particular, we consider the negatively charged muonium ion Mu$^{-}$ (or $\mu^{+} e^{-}_{2}$) and four-body…
We consider the decay of positronium to a neutrino-antineutrino accompanied by a single photon. Since the neutrino pair go undetected, this appears as a single photon decay of positronium. These decay channel are mediated through the…
We study the spectral and scattering theory of three body dispersive systems, which include a massless particle and a two body non-relativistic pair, along with two body short interactions among the three particles. We prove local decay…
The positron-hydrogen atom scattering system is considered within the S-wave model. Convergence in the elastic scattering, excitation, ionization, and positronium formation channels is studied as a function of the number and type of states…
If dark matter interactions with Standard Model particles are $CP$-violating, then dark matter annihilation/decay can produce photons with a net circular polarization. We consider the prospects for experimentally detecting evidence for such…
By solving the Faddeev equations for the \={p}pn system, we compute the antiproton-deuteron level shifts and widths for the lowest hydrogenic states as well as the corresponding \={p}d scattering lengths and volumes. The \={p}d annihilation…
Cross sections and spin asymmetries for elastic positron scattering and for the emission of positron bremsstrahlung in collision with nuclei of zero and half-integer spin are calculated within the relativistic partial-wave theory. For…
The total photodisintegration cross sections of three-body nuclei are calculated with semirealistic NN potentials below pion threshold. Full final state interaction with Coulomb force is taken into account via the Lorentz integral transform…
We analyse the kinematic regimes attainable for $J/\Psi$ and $\Psi'$ production in $p-A$ collisions. With this information, we specify the requirements for an experiment to study the interaction of physical charmonium states in nuclear…
It was recently proposed that stable particles of charge $-2$, $O^{--}$, can exist and constitute dark matter after they bind with primordial helium in O-helium (OHe) atoms. We study here in details the possibility that this model provides…
The paper deals with the Compton disintegration of positronium and a comparison of the differential cross sections of this process with the similar cross sections in the case of the Compton ionization of the hydrogen atom. Special attention…
The calculations of the elementary atom (the Coulomb bound state of elementary particles) interaction with the atom of matter, which are performed in the Born approximation, are reviewed. We first discuss the nonrelativistic approach and…
Strong coupling between light and matter is possible with a variety of organic materials. In contrast to the simpler inorganic case, organic materials often have a complicated spectrum, with vibrationally dressed electronic transitions.…
The linear Zeeman effect in the molecular positronium Ps2 (dipositronium) is predicted for some of $S=1$, $M=\pm1$ states. This result is opposite to the case of the positronium atom; the latter has only quadratic Zeeman effect.
We consider systems of a small number of interacting bosons confined to harmonic potentials in one and two dimensions. By exact numerical diagonalization of the many-body Hamiltonian we determine the low lying excitation energies and the…