Determine the origin of the simulated–experimental argon-doping discrepancy

Determine why the particle-in-cell simulations reproduce the experimental observables only with an argon doping of 0.1%, whereas the experiment used a 1% argon concentration, including whether limitations of the ADK ionization model or other experimental uncertainties account for the discrepancy.

Background

The simulations were tuned to reproduce the measured electron energy distribution, accelerated charge, and beam divergence. Although the experimental gas mixture contained 1% argon, the best-matching simulation used only 0.1% argon doping. The paper notes that the source of this mismatch is unresolved and may involve the ADK ionization model overestimating ionization rates or other experimental uncertainties.

References

The origin of this discrepancy is not understood. It may partly result from limitations of the ADK ionization model, which could overestimate ionization rates under these conditions, although other experimental uncertainties may also contribute.

— Stable 50 MeV Beams from a 100 Hz Laser-Wakefield Accelerator Driven by an OPCPA Laser  (2609.26390 - Smartsev et al., 22 Sep 2026) in Section V, “Particle-In-Cell simulations”