# Interpreting molecular hydrogen and atomic oxygen line emission of T Tauri disks with photoevaporative disk-wind models

**Authors:** Ch. Rab, M. Weber, T. Grassi, B. Ercolano, G. Picogna, P. Caselli, W. -F. Thi, I. Kamp, P. Woitke  
**arXiv:** [2210.15486](https://arxiv.org/abs/2210.15486)  
**Date:** 2022-10-27  
**Summary page:** https://www.summarizepaper.com/en/paper/2210.15486v2/

## Key points

- Protoplanetary disks are important for planet formation and evolution.
- Winds within these disks play a significant role in their dispersal and evolution, but the physical process driving these winds is still unclear.
- Theoretical models must be compared to observational data to better understand this process.
- Hydrodynamic photoevaporative disk-wind models were used to produce synthetic observables for o-H$_2$ at 2.12 micron and [OI] at 0.63 micron spectral lines, which were then compared to a sample of observations.
- The photoevaporative disk-wind model was consistent with the observed signatures of blueshifted narrow low-velocity components (NLVCs) for both tracers, except for one target out of seven that showed blueshifted NLVCs where the model failed to explain the observed line kinematics.
- Interpreting spectral line profiles by simple methods such as the thin-disk approximation can lead to misleading conclusions about the line emitting region.
- Further improvements to these models could include more consistent modeling of dynamics and chemistry as well as detailed modeling of individual targets.
- A direct comparison of magnetically driven disk-wind models to observational data would be necessary to determine if spatially unresolved observations of multiple wind tracers are sufficient for discriminating between theoretical models.
- This study provides valuable insights into protoplanetary disk winds and highlights areas where further research is needed for a more comprehensive understanding of their evolution and dispersal processes.

## Summary

Protoplanetary disks are crucial in the formation and evolution of planets. Winds within these disks play a significant role in their dispersal and evolution, but the physical process driving these winds is still unclear. To better understand this process, theoretical models must be directly compared to observational data. In this study, hydrodynamic photoevaporative disk-wind models were used to produce synthetic observables for o-H$_2$ at 2.12 micron and [OI] at 0.63 micron spectral lines, which were then compared to a sample of observations. The results showed that the photoevaporative disk-wind model was consistent with the observed signatures of blueshifted narrow low-velocity components (NLVCs), which are typically associated with slow disk winds, for both tracers. However, there was one target out of seven that showed blueshifted NLVCs where the photoevaporative model failed to explain the observed line kinematics. Additionally, interpreting spectral line profiles by simple methods such as the thin-disk approximation can lead to misleading conclusions about the line emitting region. While the photoevaporative disk-wind models were largely consistent with the studied observational data set, it was not possible to clearly discriminate between different wind-driving mechanisms. Further improvements to these models could include more consistent modeling of dynamics and chemistry as well as detailed modeling of individual targets. Furthermore, a direct comparison of magnetically driven disk-wind models to observational data would be necessary to determine if spatially unresolved observations of multiple wind tracers are sufficient for discriminating between theoretical models. Overall, this study provides valuable insights into protoplanetary disk winds and highlights areas where further research is needed for a more comprehensive understanding of their evolution and dispersal processes.