Related papers: Threshold resonance effects in reactive processes
We describe a universal transition mechanism characterizing the passage to an annealed behavior and to a regime where the fluctuations about this behavior are Gaussian, for the long time asymptotics of the empirical average of the expected…
We study the existence and location of the resonances of a $2\times 2$ semiclassical system of coupled Schr\"odinger operators, in the case where the two electronic levels cross at some point, and one of them is bonding, while the other one…
We point out a few remarkable properties of the $\gamma\gamma\to\gamma\gamma$ process at high energy. They should allow to search for effects of new particles and interactions. We give illustrations with threshold effects due to pairs of…
Recently there has been a renewed activity in the physics of violations of Lorentz invariance in the neutrino sector. Flavor dependent Lorentz violation, which generically changes the pattern of neutrino oscillations, is extremely tightly…
The diffraction of electromagnetic waves at the surface periodic structures accompanied by strong anomalous effects in different diffraction orders is considered in great detail for high-contrast interfaces. We restrict our discussion to…
Evaluation of anomalous couplings in the $\gamma\gamma\to W^+W^-$ process needs to calculate the cross section $\sigma(W^+W^-)$ with a high precision. Therefore one has to consider the main contribution of high order effects. In this paper…
A simple 1-D relativistic model for a diatomic molecule with a double point interaction potential is solved exactly in a constant electric field. The Weyl-Titchmarsh-Kodaira method is used to evaluate the spectral density function, allowing…
Physical processes involving charge transfer, spin exchange, or excitation exchange often occur in conditions of resonant scattering. We show that the $s$-wave contribution can be used to obtain a good approximation for the full cross…
We examine the temperature dependence of the optical sum rule in the normal state due to interactions. To be concrete we adopt a weak coupling approach which uses an electron-boson exchange model to describe inelastic scattering of the…
The non-relativistic cross section from Rayleigh scattering by hydrogen atoms in the ground state is calculated over a wide range of photon energies ($< 0.8$ keV). Evaluations are performed in terms of the real and imaginary components of…
The points where diffraction orders emerge or vanish in the propagating spectrum of periodic non-Hermitian systems are referred to as scattering thresholds. Close to these branch points, resonances from different Riemann sheets can…
The amplitudes for $2\rightarrow 2$ scattering processes involving longitudinally polarized gauge bosons $( W_L^\pm, Z_L )$ and the Higgs boson are analyzed up to two loops. Assuming $M_H >> M_W$, the trilinear Higgs coupling, $\lambda v$,…
We investigate isospin breaking in low-energy pion-nucleon scattering in the framework of chiral perturbation theory. This work extends the systematic analysis of [1] to the energy range above threshold. Various relations, which identically…
We study the inelastic scattering rate due to the Coulomb interaction in three-dimensional Dirac/Weyl semimetals at finite temperature. We show that the perturbation theory diverges because of the long-range nature of the interaction,…
We present a detailed investigation of the momentum-dependent self-energy Sigma(k) at zero frequency of weakly interacting bosons at the critical temperature T_c of Bose-Einstein condensation in dimensions 3<=D<4. Applying the functional…
Recently reported diboson excesses at LHC are interpreted to be connected with heavy $WW$ resonance with weak isotopic spin 2. The resonance appears due to the wouldbe anomalous triple interaction of the weak bosons, which is defined by…
We apply the quantum-defect theory for $-1/R^4$ potential to study the resonant charge exchange process. We show that by taking advantage of the partial-wave-insensitive nature of the formulation, resonant charge exchange of the type of…
We consider reflection of electromagnetic waves from layered structures with various dielectric and magnetic properties, including metamaterials. Assuming periodic variations in the permittivity, we find that the reflection is in general…
We show that it is essential to include renormalisation group (RG) effects for determining the SMEFT parameter space consistent with the CDF W-mass anomaly at the matching scale. This is because operators that are only weakly…
Two approaches (micro- and macro- investigations) are used to determine the dimension dependences of the optical parameters of the nanometer-scale layers of materials. It is shown that both an index of refraction and coefficient of…