Separate and quantify neglected electromagnetic contributions to the retrieval

Quantify the individual contributions of dependent scattering and higher-order scattering to the terahertz radar solids-concentration retrieval under dense gas–solid flow conditions, since the reported comparison with pressure-derived concentrations does not isolate these electromagnetic effects.

Background

The paper evaluates the independent-scattering and single-scattering assumptions a posteriori and finds that the radar and pressure concentration profiles agree under the tested conditions. This agreement supports the overall closure but cannot determine which neglected electromagnetic mechanisms may contribute to any residual error.

The authors explicitly state that the validation does not isolate or quantify the individual effects of dependent scattering and higher-order scattering. Thus, determining the magnitude and separate influence of these mechanisms remains unresolved and is important for extending the method beyond the experimentally investigated conditions.

References

It cannot, however, isolate or quantify the individual electromagnetic effects.

— Terahertz Radar Inversion for Range-Resolved Solids Concentration Profiling in Gas--Solid Flows  (2609.18567 - Jepsen et al., 16 Sep 2026) in Section Measurement Results and Discussion, paragraph beginning “The agreement between the radar- and pressure-derived…”