# Overcoming the structural surface effect with a realistic treatment of turbulent convection in 1D stellar models

## TL;DR

This paper introduces a new method that integrates 3D hydrodynamic simulations into 1D stellar models to accurately represent surface convection, correcting structural errors and improving stellar evolution predictions.

## Contribution

The authors develop a technique that incorporates mean 3D turbulent pressure from hydrodynamic simulations into 1D stellar models, enhancing their realism and accuracy.

## Key findings

- Corrects surface layer errors in solar models
- Improves agreement of oscillation frequencies with observations
- Alters predicted solar evolution trajectories

## Abstract

State-of-the-art one-dimensional (1D) stellar evolution codes rely on simplifying assumptions, such as mixing length theory, in order to describe superadiabatic convection. As a result, 1D stellar structure models do not correctly recover the surface layers of the Sun and other stars with convective envelopes. We present a method that overcomes this structural drawback by employing three-dimensional (3D) hydrodynamic simulations of stellar envelopes: at every time-step of the evolution interpolated 3D envelopes are appended to the 1D structure and are used to supply realistic boundary conditions for the stellar interior. In contrast to previous attempts, our method includes mean 3D turbulent pressure. We apply our method to model the present Sun. The structural shortcomings of standard stellar models lead to systematic errors in the stellar oscillation frequencies inferred from the model. We show that our method fully corrects for this error. Furthermore, we show that our realistic treatment of superadiabatic convection alters the predicted evolution of the Sun. Our results hence have important implications for the characterization of stars. This has ramifications for neighbouring fields, such as exoplanet research and galactic archaeology, for which accurate stellar models play a key role.