Modern Time-Series and Spectral Methods for Analyzing Solar and Stellar Oscillatory Signals
A comprehensive review examines methods for detecting and characterizing periodic oscillations in solar and stellar atmospheres, addressing challenges from instrumental noise and uneven sampling. The paper compares Fourier-based approaches, wavelet transforms, Lomb-Scargle periodograms, and adaptive decomposition techniques, with emphasis on proper statistical significance testing. The work provides practical guidelines for selecting appropriate analysis methods and identifies future directions combining Bayesian inference with time-frequency analysis.
This arXiv preprint presents a detailed methodological review of time-series analysis techniques used to study oscillatory phenomena in the Sun and stars. The authors address fundamental challenges in astrophysical observations—instrumental noise, non-stationary dynamics, and irregular sampling—that complicate the detection and characterization of periodicities. The review covers multiple analytical approaches including Fourier transforms, the Lomb-Scargle periodogram, wavelet and synchrosqueezed transforms, and Empirical Mode Decomposition, alongside advanced statistical significance tests such as false-alarm probability calculations, autoregressive models, and Bayesian MCMC methods. Through comparative analysis using synthetic benchmarks, the authors provide evidence-based guidelines for selecting methods appropriate to specific signal characteristics. The paper emphasizes practical limitations and common misuses of statistical tests, and proposes integrating Bayesian inference with time-frequency analysis to improve both statistical rigor and temporal localization in studying non-stationary oscillations.
What's missing
The preprint does not discuss specific observational applications or results from applying these methods to particular solar or stellar systems, focusing instead on methodological comparison and theoretical framework.
What different sources said
- arXiv astro-phCenter
Modern Time-Series and Spectral Methods for Analyzing Solar and Stellar Oscillatory Signals
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