Related papers: Positronium-Atom Collisions
In molecular collisions, resonances occur at specific energies where the colliding particles temporarily form quasi-bound complexes, resulting in rapid variations in the energy dependence of scattering cross sections. Experimentally, it has…
We estimate differential rapidity cross sections for $J/\Psi$, $\Psi(2S)$, $\Upsilon(1S)$, $\Upsilon(2S)$, and $\Upsilon(3S)$ production via Pb-Pb collisions at proton-proton energy $\equiv \sqrt{s_{pp}}$ =5.02 TeV. For the $\Psi(2S)$,…
The rate constants required to model the OH$^+$ observations in different regions of the interstellar medium have been determined using state of the art quantum methods. First, state-to-state rate constants for the H$_2(v=0,J=0,1)$+…
Inelastic processes rate coefficients for low-energy Sr + H, Sr$^+$ + H$^-$, Sr$^+$ + H and Sr$^{2+}$ + H$^-$ collisions are calculated using multichannel quantum model approach. 31 scattering channels of SrH$^+$ and 17 scattering channels…
Hylleraas-Configuration Interaction (Hy-CI) calculations on the ground $1^1$S state of helium atom are presented using s-, p-, d-, and f-Slater orbitals of both real and complex form. Techniques of construction of adapted configurations,…
Confined states of a positronium (Ps) in the spherical and circular quantum dots (QDs) are theoretically investigated in two size-quantization regimes: strong and weak. Two-band approximation of Kane dispersion law and parabolic dispersion…
Recently, the LHCb Collaboration reported pronounced structures in the invariant mass spectrum of $J/\psi$-pairs produced in proton-proton collisions at the Large Hadron Collider. In this Letter, we argue that the data can be very well…
We analyze atom-atom correlations in the s-wave scattering halo of two colliding condensates. By developing a simple perturbative approach, we obtain explicit analytic results for the collinear (CL) and back-to-back (BB) correlations…
At low energies, the quantum wave-like nature of molecular interactions result in unique scattering behavior, ranging from the universal Wigner laws near zero Kelvin to the occurrence of scattering resonances at higher energies. It has…
The experimental characterization of scattering resonances in low energy collisions has proven to be a stringent test for quantum chemistry calculations. Previous measurements on the NO-H$_2$ system at energies down to $10$ cm$^{-1}$…
We present preliminary results on the $I=0$, $S=-2$ $H$ dibaryon in $N_{\rm f}=2+1$ QCD. The calculation is performed with heavier-than-physical quarks ($m_\pi \approx 280$ MeV) on a single CLS ensemble. Correlation matrices are constructed…
Single-electron ionization and excitation cross sections as well as cross sections for excitation into the first excited p state of the alkali metal atoms Li(2s), Na(3s) and K(4s) colliding with antiprotons and protons were calculated using…
We perform a theoretical analysis of atomic four-wave mixing via a collision of two Bose-Einstein condensates of metastable helium atoms, and compare the results to a recent experiment. We calculate atom-atom pair correlations within the…
The elastic and inelastic high--energy small--angle electron--positron scattering is considered. All radiative corrections to the cross--section with the relative accuracy $\delta\sigma/ \sigma = 0.1 \% $ are explicitly taken into account.…
We present phase-shift calculations for positron collisions with positive ions using a complex scaling method (CSM). Based on the findings of this study [R. Suzuki, T. Myo, and K. Kat\={o}, Prog. Theor. Phys. 113, 1273 (2005).], we propose…
The collision of two equilibrium ground state solutions of the Schr\"odinger-Poisson (SP) system, in orthogonal states, is proposed as a formation mechanism of mixed state solutions of the SP system with spherical and first dipolar…
We develop a rigorous quantum mechanical theory for collisions of polyatomic molecular radicals with S-state atoms in the presence of an external magnetic field. The theory is based on a fully uncoupled space-fixed basis set representation…
The influence of the dissipative terms on the conditions of formation and the characteristic parameters of shock waves in relativistic nuclear collisions is investigated for three types of equation of state (non linear QHD-1, resonance gas…
The Positronium (Ps) system, a bound state of an electron and a positron, is suitable for testing the predictions of quantum electrodynamics (QED), since its properties can be perturbatively calculated to high accuracy and, unlike the…
Full-dimensional quantum scattering calculations are reported for ro-vibrational transitions in HD+HD collisions using a highly accurate interaction potential for the H$_2$-H$_2$ system. Several near-resonant ro-vibrational transitions are…