希少なハートビートスターを自動識別するニューラルネットワーク手法を開発(Researchers Develop Neural Network Method to Automatically Identify Rare Heartbeat Stars)

2025-09-30 中国科学院(CAS)

中国科学院雲南天文台の研究チームは、神経ネットワークを用いて「ハートビート星」と呼ばれる稀少な連星系を自動識別する手法を開発した。ハートビート星は心電図のような光度曲線を示し、潮汐励起振動(TEOs)を伴うことが多く、恒星内部構造や連星進化研究に有用だが、光度曲線の多様性ゆえ従来の手作業識別は困難だった。研究者らはフーリエスペクトルから抽出した軌道高調波を入力特徴として神経ネットワークを訓練し、既知のハートビート星を86%の精度で識別。ケプラー望遠鏡のデータから153例を解析し、最大規模のデータベースを構築するとともに21個の新規TEO系を発見した。また自動ツールにより高調波/非高調波の振動を識別し、14例の位相や振動モードを同定。今後TESSや中国宇宙ステーション望遠鏡(CSST)にも応用可能と期待される。

希少なハートビートスターを自動識別するニューラルネットワーク手法を開発(Researchers Develop Neural Network Method to Automatically Identify Rare Heartbeat Stars)
Light curves of four heartbeat stars exhibiting tidally excited oscillations. (Image by LI Minyu)

<関連情報>

リカレントニューラルネットワークに基づくハートビートスター認識:手法と検証 Heartbeat Stars Recognition Based on Recurrent Neural Networks: Method and Validation

Min-Yu Li, Sheng-Bang Qian, Li-Ying Zhu, Wen-Ping Liao, Lin-Feng Chang, Er-Gang Zhao, Xiang-Dong Shi, Fu-Xing Li, Qi-Bin Sun, and Ping Li
The Astronomical Journal  Published: 2025 August 13
DOI:10.3847/1538-3881/aded86

Abstract

Since the variety of their light curve morphologies, the vast majority of the known heartbeat stars (HBSs) have been discovered by manual inspection. Machine learning, which has already been successfully applied to the classification of variable stars based on light curves, offers another possibility for the automatic detection of HBSs. We propose a novel feature extraction approach for HBSs. First, the orbital frequencies are calculated automatically according to the Fourier spectra of the light curves. Then, the amplitudes of the first 100 harmonics are extracted. Finally, these harmonics are normalized as feature vectors of the light curve. A training data set of synthetic light curves is constructed using ELLC, and their features are fed into recurrent neural networks (RNNs) for supervised learning, with the expected output being the eccentricity of these light curves. The performance of the RNNs is evaluated using a test data set of synthetic light curves, achieving 95% accuracy. When applied to known HBSs from the Optical Gravitational Lensing Experiment, Kepler, and Transiting Exoplanet Survey Satellite surveys, the networks achieve an average accuracy of 86%. This method successfully identifies four new HBSs within the eclipsing binary catalog of Kirk et al. The use of orbital harmonics as features for HBSs proves to be a practical approach that significantly reduces the computational cost of neural networks. RNNs show excellent performance in recognizing this type of time series data. This method not only allows efficient identification of HBSs but can also be extended to recognize other types of periodic variable stars.

1701物理及び化学
ad
ad
Follow
ad
タイトルとURLをコピーしました