Determine whether alternative drift-model setups can substantially alter the coldest-water diagnostic

Determine whether different protoplanetary-disc model setups that include pebble drift can produce a more significant change in the coldest-water line diagnostic than the model configurations examined here.

Background

The paper examines how chemistry, turbulent diffusion, advection, coagulation, fragmentation, and icy-pebble drift affect simulated JWST/MIRI water spectra and line-ratio diagnostics. In the fiducial model with pebble drift, the coldest-water tracer changes only slightly, despite substantial enhancements of the hot and warm water reservoirs.

Because the analysis uses only a small grid of disc and pebble-transport configurations, the authors explicitly state that they cannot determine whether other model setups involving drift could generate a substantially larger change in the coldest-water diagnostic. Resolving this issue would clarify whether pebble drift can account for the observed diversity in the coldest observable water emission.

References

From the small grid of models, we cannot conclude if different model setups including drift could lead to a more significant change.

— Around the water snowline: I. Effects of dynamical and chemical interplay on mid-infrared water spectra of protoplanetary discs  (2609.17016 - Kaeufer et al., 15 Sep 2026) in Discussion, subsection “Impact of pebble drift on line diagnostics”