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arXiv · 2509.08189

A neural network model for quickly solving multiple-band light curves of contact binaries

Abstract

The advent of large-scale photometric surveys has led to the discovery of over a million contact binary systems. Conventional light curve analysis methods are no longer adequate for handling such massive datasets. To address this challenge, we developed a neural network-based model capable of rapid analysis of multiple-band light curves of contact binaries. Our model can determine the fundamental physical parameters, including temperature and mass ratios, orbital inclination, potential, fillout factor, primary and secondary luminosities and radii, third light contribution, and spot parameters. Notably, unlike previous works, our model can simultaneously process multiple-band light curves and the four parameters of a starspot. The model's reliability was verified through analysis of the synthetic light curves generated by PHOEBE and the light curves of eight targets from \cite{2024ApJ...976..223W}'s work. The discrepancy distribution between the physical parameters determined by our model and true values for the synthetic light curves shows very good agreement. In addition, the physical parameters determined by our model and the corresponding light curve fits show remarkable consistency with \cite{2024ApJ...976..223W}'s results. By applying our model to OGLE contact binaries, physical parameters of 3,541 systems were obtained. We have packaged our model into an executable (CBLA.exe) file and archived it in the China-VO repository (https://doi.org/10.12149/101626). The software supports light curve analysis of 19 standard filters and allows for processing the data, whether from large-scale sky surveys or individual telescope observations.

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Kai Li, Li-Heng Wang, Xiang Gao. 2025-09-09. A neural network model for quickly solving multiple-band light curves of contact binaries. https://arxiv.org/abs/2509.08189

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