Stellar mass and radius estimation using Artificial Intelligence

TL;DR

This paper develops and evaluates AI regression models, especially stacking, for estimating stellar masses and radii, achieving significantly improved accuracy over traditional empirical relations and providing tools for the astrophysics community.

Contribution

It introduces a novel AI-based approach, particularly stacking models, for stellar parameter estimation, outperforming existing empirical methods and releasing a public database and online tool.

Findings

Stacking models yield the highest accuracy for mass and radius estimation.

Neural Networks and Support-Vector Regression are effective for specific parameters.

The AI models improve accuracy by a factor of two compared to traditional empirical relations.

Abstract

Estimating stellar masses and radii is a challenge for most of the stars but their knowledge is critical for many different astrophysical fields. One of the most extended techniques for estimating these variables are the so-called empirical relations. In this work we propose a group of state-of-the-art AI regression models, with the aim of studying their proficiency in estimating stellar masses and radii. We publicly release the database, the AI models, and an online tool for stellar mass and radius estimation to the community. We use a sample of 726 MS stars in the literature with accurate M, R, T_eff, L, log g, and [Fe/H]. We have split our data sample into training and testing sets and then analyzed the different AI techniques with them. In particular, we have experimentally evaluated the accuracy of the following models: Linear Reg., Bayesian Reg., Regression Trees, Random Forest, Support-Vector Reg. (SVR), Neural Networks, kNN, and Stacking. We propose a series of experiments designed to evaluate the accuracy of the estimations. We have also analyzed the impact of reducing the number of inputs parameters and compared our results with those from state-of-the-art empirical relations in the literature. We have found that a Stacking of several regression models is the most suitable technique for estimating masses and radii. In the case of the mass, Neural Networks also provide precise results, and for the radius, SVR and Neural Networks work too. When comparing with other state-of-the-art empirical relations based models, our Stacking improves the accuracy by a factor of two for both variables. In addition, bias is reduced to one order of magnitude in the case of the stellar mass. Finally, we have found that using our Stacking and only T_eff and L as input features, the accuracies obtained are slightly larger than a 5%, with a bias approx 1.5%.