相关论文: The leading term of the He$-\bar{p}\mbox{He}^+$ lo…
The energetically lowest five states of a helium atom are: He($1^1S$), He($2^3S$), He($2^1S$), He($2^3P$), and He($2^1P$). Long-range interaction coefficients $C_3$, $C_6$, $C_8$, $C_9$, and $C_{10}$ for all $S-S$ and $S-P$ pairs of these…
A general formalism is used to express the long-range potential energies in inverse powers of the separation distance between two like atomic or molecular systems with $P$ symmetries. The long-range molecular interaction coefficients are…
The shift and broadening of the resonance lines in spectrum of the antiprotonic helium atoms $\bar{p}\mathrm{He}^{+}$ located in fluid and superfluid $^4$He have been calculated. The contributions to the shift and broadening from collective…
Radiative charge exchange collisions between a carbon atom C(${}^3$P) and a helium ion He+, both in their ground state, are investigated theoretically. Detailed quantum chemistry calculations are carried out to obtain potential energy…
Potential Energy Surface for the ($\mathrm{\bar{p}} - \mathrm{He}^{2+} - \mathrm{He}$) system is calculated in the framework of the restricted (singlet spin state) Hartree-Fock method with subsequent account of the electronic correlations…
We have estimated the shift and broadening of the resonance lines in the spectrum of antiprotonic helium atoms $\bar{p}\mathrm{He}^{+}$ implanted in solid helium $^4$He. The application of the response function for crystalline helium has…
Polarizabilities, dispersion coefficients, and long-range atom-surface interaction potentials are calculated for the n=2 triplet and singlet states of helium using highly accurate, variationally determined, wave functions.
We develop a numerical method to calculate the Bethe logarithm for resonant states. We use the Complex Coordinate Rotation (CCR) formalism to describe resonances as time-independent Schr\"odinger solutions. To get a proper expression for…
For the interactions between a He($2 ^3S$) atom and a He($2 ^3P$) atom for like isotopes, we report perturbation theoretic calculations using accurate variational wave functions in Hylleraas coordinates of the coefficients determining the…
We present ionization cross sections for antiproton and helium collisions based on ab-initio time-dependent coupled channel method. In our calculations a finite basis set of regular helium Coulomb wave packets and Slater function were used.…
The dispersion coefficients $C_6$, $C_8$, and $C_{10}$ for the interactions between H, He, and Li are calculated using variational wave functions in Hylleraas basis sets with multiple exponential scale factors. With these highly correlated…
The static dipole polarizability of metastable states in the kaonic helium atoms is studied. We use the complex coordinate rotation method to properly account for the resonant nature of the states. Our calculations show that some of the…
A few per cent fraction of antiprotons stopped in helium survives for an enormous time (up to tens of microseconds) in comparison with the usual lifetime ($10^{-12}s$) of these particles in matter. The explanation is that antiprotons are…
Theory of long-range interactions between an atom in its ground S state and a linear molecule in a degenerate state with a non-zero projection of the electronic orbital angular momentum is presented. It is shown how the long-range…
A systematic study of the decay rates of antiprotonic helium (\pbhef and \pbhet) at CERN AD (Antiproton Decelerator) has been made by a laser spectroscopic method. The decay rates of some of its short-lived states, namely those for which…
We consider a neutralization of excited antiprotonic helium ion accompanied by antiproton transitions to lower states in collisions with helium atoms $(\bar{p}\mathrm{He}^{2+})_{nl} + \mathrm{He} \rightarrow \left[…
Apropos to the growing interest in the study of long-range interactions which for their applications in cold atom physics, we have performed theoretical calculation for the two-dipole $C_6$ and three-dipole $C_9$ dispersion coefficients…
Recent experiments on the laser-induced resonant annihilation provide a precise measurement of transition energies of antiprotonic helium atoms. Relativistic corrections of an order of $\alpha ^2$ to the pure Coulomb interaction will be…
We theoretically investigate long-range interactions between an excited $L$ state He atom and two identical $S$ state He atoms, for the cases of the three atoms all in spin singlet states or all in spin triplet states, denoted by…
We present the first fully ab initio calculations of collision-induced broadening and shift of spectral lines in antiprotonic helium ($\bar{p}$He$^{+}$) perturbed by atomic helium. To overcome critical limitations of previous studies, we…