# Observing Thermal Schwinger Pair Production

## TL;DR

This paper explores how a thermal photon bath can significantly enhance Schwinger pair production, identifying specific regimes where this effect becomes observable, though current technology limitations pose challenges.

## Contribution

It introduces the concept of thermal enhancement of Schwinger pair production, highlighting regimes with exponential amplification due to nonperturbative effects beyond one-loop calculations.

## Key findings

- Thermal enhancement can exponentially increase pair production rates.
- Observable effects require very high temperatures (~20 keV) and field intensities (~10^{23} W/cm^2).
- Nonthermal photon distributions might produce similar effects at lower temperatures.

## Abstract

We study the possibility of observing Schwinger pair production enhanced by a thermal bath of photons. We consider the full range of temperatures and electric field intensities from pure Schwinger production to pure thermal production, and identify the most promising and interesting regimes. In particular, we identify temperatures of $\sim 20~\mathrm{keV}/k_B$ and field intensities of $\sim 10^{23}~\mathrm{Wcm}^{-2}$ where pair production would be observable. In this case, the thermal enhancement over the Schwinger rate is exponentially large and due to effects which are not visible at any finite order in the loop expansion. Pair production in this regime can thus be described as more nonperturbative than the usual Schwinger process, which appears at one loop. Unfortunately, such high temperatures appear to be out of reach of foreseeable technologies, though nonthermal photon distributions with comparable energy densities are possible. We suggest the possibility that similar nonperturbative enhancements may extend out of equilibrium and propose an experimental scheme to test this.