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A. Di Piazza

Publications and source records attributed to A. Di Piazza.

77 records · Page 5Linked to original sources

Delbrück scattering in combined Coulomb and laser fields

We study Delbrück scattering in a Coulomb field in the presence of a laser field. The amplitudes are calculated in the Born approximation with respect to the Coulomb field and exactly in the parameters of the laser field having arbitrary strength, spectral content and polarization. The case of high energy initial photon energy is investigated in detail for a monochromatic circularly polarized laser field. It is shown that the angular distribution of the process substantially differs from that for Delbrück scattering in a pure Coulomb field. The value of the cross section under discussion may exceed the latter at realistic laser parameters that essentially simplify the possibility of the experimental observation of the phenomenon. The effect of high order terms in the quantum intensity parameter $χ$ of the laser field is found to be very important already at relatively small $χ$.

physics.atom-ph↗

Photon splitting in a laser field

Photon splitting due to vacuum polarization in a laser field is considered. Using an operator technique, we derive the amplitudes for arbitrary strength, spectral content and polarization of the laser field. The case of a monochromatic circularly polarized laser field is studied in detail and the amplitudes are obtained as three-fold integrals. The asymptotic behavior of the amplitudes for various limits of interest are investigated also in the case of a linearly polarized laser field. Using the obtained results, the possibility of experimental observation of the process is discussed.

hep-ph↗

Non-perturbative vacuum-polarization effects in proton-laser collisions

In the collision of a high-energy proton beam and a strong laser field, merging of the laser photons can occur due to the polarization of vacuum. The probability of photon merging is calculated by accounting exactly for the laser field and presents a highly non-perturbative dependence on the laser intensity and frequency. It is shown that the non-perturbative vacuum-polarization effects can be experimentally measured by combining the next-generation of table-top petawatt lasers with presently available proton accelerators.

hep-ph↗

Enhancement of vacuum polarization effects in a plasma

The dispersive effects of vacuum polarization on the propagation of a strong circularly polarized electromagnetic wave through a cold collisional plasma are studied analytically. It is found that, due to the singular dielectric features of the plasma, the vacuum effects on the wave propagation in a plasma are qualitatively different and much larger than those in pure vacuum in the regime when the frequency of the propagating wave approaches the plasma frequency. A possible experimental setup to detect these effects in plasma is described.

hep-ph↗

Light diffraction by a strong standing electromagnetic wave

The nonlinear quantum interaction of a linearly polarized x-ray probe beam with a focused intense standing laser wave is studied theoretically. Because of the tight focusing of the standing laser pulse, diffraction effects arise for the probe beam as opposed to the corresponding plane wave scenario. A quantitative estimate for realistic experimental conditions of the ellipticity and the rotation of the main polarization plane acquired by the x-ray probe after the interaction shows that the implementation of such vacuum effects is feasible with future X-ray Free Electron Laser light.

hep-ph↗