# Modeling protoplanetary disk SEDs with artificial neural networks: Revisiting the viscous disk model and updated disk masses

**Authors:** Á. Ribas, C. C. Espaillat, E. Macías, L. M. Sarro  
**arXiv:** [2009.03323](https://arxiv.org/abs/2009.03323)  
**Date:** 2020-09-07  
**Summary page:** https://www.summarizepaper.com/en/arxiv-id/2009.03323v1/

## Key points

- A recent study modeled the spectral energy distributions (SEDs) of 23 protoplanetary disks in the Taurus-Auriga star-forming region.
- Detailed disk models and a Bayesian approach were used, combined with artificial neural networks to speed up performance.
- High viscosities and accretion rates were found for many sources, inconsistent with recent measurements of low turbulence levels in disks.
- This suggests that viscosity may not be the main mechanism for angular momentum transport in disks and that alternatives such as disk winds play an important role.
- SED-derived disk masses were systematically higher than those obtained solely from (sub)mm fluxes, suggesting part of the disk emission could still be optically thick at (sub)mm wavelengths.
- This has implications for disk population studies and alleviates previous observational tensions between the masses of protoplanetary disks and exoplanetary systems.
- The study highlights the importance of considering alternative mechanisms for angular momentum transport in protoplanetary disks and accounting for uncertainties and degeneracies when modeling SEDs.

## Summary

In a recent study, the spectral energy distributions (SEDs) of 23 protoplanetary disks in the Taurus-Auriga star-forming region were modeled using detailed disk models and a Bayesian approach. The researchers combined these models with artificial neural networks to significantly speed up their performance, allowing them to confront $\alpha$-disk models with observations while accounting for several uncertainties and degeneracies. The results of the study revealed high viscosities and accretion rates for many sources, which is not consistent with recent measurements of low turbulence levels in disks. This inconsistency could imply that viscosity is not the main mechanism for angular momentum transport in disks and that alternatives such as disk winds play an important role. Additionally, the SED-derived disk masses obtained from the study were systematically higher than those obtained solely from (sub)mm fluxes. This suggests that part of the disk emission could still be optically thick at (sub)mm wavelengths, which has implications for disk population studies and alleviates previous observational tensions between the masses of protoplanetary disks and exoplanetary systems. Overall, this study provides new insights into protoplanetary disks by highlighting the importance of considering alternative mechanisms for angular momentum transport in these systems. It also emphasizes the need to account for uncertainties and degeneracies when modeling SEDs and deriving disk properties.