Recombination fluorescence in ultracold neutral plasmas

TL;DR

This paper reports the first measurements and simulations of recombination fluorescence in ultracold neutral plasmas, revealing significant discrepancies that suggest new insights into electron energy distributions and scattering processes.

Contribution

It introduces the first experimental and simulation study of recombination fluorescence in ultracold plasmas, highlighting discrepancies and potential new diagnostic methods.

Findings

Experiment and simulation disagree significantly.

Discrepancies may be due to high-energy electron distributions.

Recombination fluorescence probes deeply-bound Rydberg levels.

Abstract

We present the first measurements and simulations of recombination fluorescence in ultracold neutral plasmas. In contrast with previous work, experiment and simulation are in significant disagreement. Comparison with a recombination model suggests that the disagreement could be due to the high energy portion of the electron energy distribution or to large energy changes in electron/Rydberg scattering. Recombination fluorescence opens a new diagnostic window in ultracold plasmas because it probes the deeply-bound Rydberg levels, which depend critically on electron energetics.