Impact of self-consistent X-ray radiative transfer and time-dependent irradiation

Quantify how self-consistent X-ray radiative transfer through protoplanetary disks, including X-ray scattering and absorption by dust and gas and time-dependent X-ray irradiation, changes predicted molecular abundances and mid-infrared line emission.

Background

The IRIS models do not include X-ray radiative transfer through the disk. Consequently, they omit the effects of X-ray scattering and absorption by dust and gas on the local radiation field, even though X-ray penetration can alter the disk’s thermal and chemical structure.

The authors explicitly identify the influence of these omitted processes on molecular abundances and line emission as requiring future quantification. Addressing this problem would improve the physical realism of the ProDiMo models and clarify whether the simplified treatment of stellar X-rays affects the predicted infrared diagnostics.

References

However, it is unclear why this effect would be evident in only two of the four transition disks in the sample.

— Mapping Molecular Ion Distributions in a Diverse Sample of Protoplanetary Disks  (2609.19313 - Long et al., 16 Sep 2026) in Section 4.1, subsection “Transition Disk Cavities”

Future work should quantify the impact of including X-ray radiative transfer self-consistently on the predicted molecular abundances and line emission, as well as the effects of time-dependent X-ray irradiation.

— XUE. ProDiMo models of internally and externally irradiated planet-forming disks around 0.3-4.0 solar mass stars (The IRIS project I)  (2609.08621 - Frediani et al., 8 Sep 2026) in Section "Model limitations"