Momentum distribution of particles created in space-time-dependent colliding laser pulses

TL;DR

This paper investigates how spatial variations in colliding laser pulses influence particle pair-production, revealing significant differences in probabilities and momentum spectra compared to simplified models, which is crucial for future research.

Contribution

It introduces a nonperturbative method accounting for full coordinate dependence, surpassing previous dipole and standing-wave approximations in analyzing pair-production.

Findings

Pair-production probabilities are significantly reduced with full spatial modeling.

Momentum spectra exhibit dramatic changes due to spatial variations.

Pulse shape effects are less influential in the more accurate model.

Abstract

We study the pair-production process in the presence of two counterpropagating linearly polarized short laser pulses. By means of a nonperturbative technique, we take into account the full coordinate dependence of the external field going beyond the dipole and standing-wave approximations. In particular, we analyze the momentum distribution of particles created. It is demonstrated that the spatial variations of the laser pulses may play a crucial role. The more accurate treatment reveals a number of prominent features: the pair-production probabilities become considerably smaller, the quantitative behavior of the momentum spectra changes dramatically, and the pulse shape effects become much less pronounced. The results of our study are expected to be very important for future theoretical and experimental investigations.