Related papers: DVCS via color dipoles: Nonperturbative effects
We develop methods needed to perform loop calculations in light cone perturbation theory using a helicity basis, refining the method introduced in our earlier work. In particular this includes implementing a consistent way to contract the…
In deeply virtual Compton scattering (DVCS) it is found that in some kinematics angular momentum is not conserved if the amplitudes are calculated in terms of widely used reduced operators. Consequently, those kinematics will lead to the…
We present the color dipole phenomenology of diffractive photo- and electroproduction $\gamma^{*} N\to V(V') N$ of vector mesons ($V(1S) = \phi^0, \omega^0, \rho^0, J/\Psi, \Upsilon$) and their radial excitations ($V'(2S) = \phi', \omega',…
In this contribution we analyse the cross sections for the exclusive vector meson production as well as the deeply virtual Compton scattering (DVCS) relying on the color dipole approach and considering the numerical solution of the…
Based upon the color-dipole picture, we provide closed analytic expressions for the longitudinal and the transverse photoabsorption cross sections at low values of the Bjorken variable of x<0.1. We compare with the experimental data for the…
Van der Waals interactions are ubiquitous and they play an important role for the stability of materials. Current understanding of this type of coupling is based on linear response theory, while optical nonlinearities are rarely considered…
Dark photon is a massive vector particle which couples to the physical photon through the kinetic mixing term. Such particles, if exist, are produced in photon beams and, in particular, in laser radiation. Due to the oscillations between…
The resonance fluorescence emitted by a system of two dipole-dipole interacting nearby four-level atoms in J=1/2 - J=1/2 configuration is studied. This setup is the simplest realistic model system which provides a complete description of…
The bulk photovoltaic effect is an example of a non-linear optical response that leads to a DC current that is relevant for photo-voltaic applications. In this work, we theoretically study this effect in the presence of electron-phonon…
We construct an invariant basis for Compton scattering with two virtual photons (VVCS). The basis tensors are chosen to be gauge invariant and orthogonal to each other. The properties of the corresponding 18 invariant amplitudes are studied…
We investigate two-color photon correlations in the light emitted by strongly coupled two-level emitters. Spectral filtering allows us to manipulate the collected light statistics and we show that the resonances induced by dipole-dipole…
Based on the Lindblad master equation approach we obtain a detailed microscopic model of photons in a dye-filled cavity, which features condensation of light. To this end we generalise a recent non-equilibrium approach of Kirton and Keeling…
Starting from a genuinely nonperturbative formulation of photon-proton scattering we discuss which approximations and assumptions are required to obtain the dipole picture of high energy scattering.
We demonstrate how the virtual photoproduction of vector mesons on nuclei scans the wave function of vector mesons from the large non-perturbative transverse size $\rho \sim R_{V}$ down to the small perturbative size $\rho \sim…
Diffractive deeply virtual Compton scattering (DiDVCS) is the process $\gamma^*(- Q^2) + N \rightarrow \rho^0 + \gamma^* (Q'^2)+ N'$, where N is a nucleon or light nucleus, in the kinematical regime of large rapidity gap between the…
Based on the color dipole representation, we investigate consequences for the $\gamma^{*}\gamma^{*},\gamma^{*}\gamma$ scattering of the finding by Fadin, Kuraev and Lipatov that incorporation of asymptotic freedom into the BFKL equation…
Two-dimensional coherent spectroscopy (2DCS) is a nonlinear spectroscopy technique capable of identifying whether apparent continua in linear response are made out of multiplets of sharp deconfined quasiparticles. This makes it a potent…
We briefly summarize the equivalence of off-diagonal generalized vector dominance and the colour-dipole approach to deep-inelastic scattering (DIS) in the diffraction region of values of $x \simeq Q^2/W^2 << 1$.
We present a method to compute, by numerical simulations of lattice QCD, the light-cone wave functions which enter exclusive processes at large momentum transfer, such as electromagnetic elastic scatterings, or exclusive semi-leptonic…
We investigate the leading-twist light-cone distribution amplitudes for the pion and kaon, based on the nonlocal chiral quark model from the instanton vacuum. Effects of explicit flavor SU(3)-symmetry breaking are taken into account. The…