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Published on: June 28, 2018
Nonperturbative vacuum-polarization effects in proton-laser collisions
A Di Piazza1, K Z Hatsagortsyan, C H Keitel
1Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany. dipiazza@mpi-hd.mpg.de
Physical Review Letters
|February 1, 2008
Summary
Photon merging in high-energy proton and laser collisions can be observed due to vacuum polarization. This nonperturbative effect, dependent on laser intensity and frequency, is measurable with current technology.
Area of Science:
- Quantum Electrodynamics (QED)
- High-Energy Physics
- Laser-Plasma Physics
Background:
- Vacuum polarization is a key QED effect where virtual particle-antiparticle pairs modify electromagnetic fields.
- Photon merging is a predicted nonlinear QED process, but its experimental observation is challenging.
- High-intensity lasers and particle beams offer new regimes to probe nonlinear QED.
Purpose of the Study:
- To investigate the probability of photon merging in high-energy proton-laser collisions.
- To analyze the dependence of photon merging on laser intensity and frequency.
- To determine the feasibility of experimental observation for nonperturbative vacuum-polarization effects.
Main Methods:
- Calculating the photon merging probability by precisely accounting for the strong laser field.
- Employing a theoretical framework that captures highly nonperturbative dependencies on laser parameters.
- Simulating the interaction between a high-energy proton beam and a strong laser field.
Main Results:
- The probability of photon merging exhibits a highly nonperturbative dependence on laser intensity and frequency.
- Nonperturbative vacuum-polarization effects significantly influence photon merging.
- The study provides a theoretical basis for observing these effects.
Conclusions:
- Photon merging due to vacuum polarization is a theoretically predicted phenomenon in proton-laser collisions.
- The probability of this process is strongly dependent on the laser field's nonperturbative characteristics.
- Experimental verification is feasible using next-generation petawatt lasers and available proton accelerators.
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