New Suns in the Cosmos III: multifractal signature analysis

TL;DR

This study analyzes multifractal signatures in astrophysical time series from the CoRoT spacecraft, revealing that correlation structures primarily drive multifractality and that stellar rotation periods are linked to multifractal degrees.

Contribution

It introduces a multifractal analysis approach to astrophysical data, highlighting the dominant role of correlations over heavy tails and connecting multifractality to stellar rotation periods.

Findings

Correlation structure is the main source of multifractality.

Heavy-tailed distributions have a minor effect on multifractality.

Multifractality degree correlates with stellar rotation periods.

Abstract

In present paper, we investigate the multifractality signatures in hourly time series extracted from CoRoT spacecraft database. Our analysis is intended to highlight the possibility that astrophysical time series can be members of a particular class of complex and dynamic processes which require several photometric variability diagnostics to characterize their structural and topological properties. To achieve this goal, we search for contributions due to nonlinear temporal correlation and effects caused by heavier tails than the Gaussian distribution, using a detrending moving average algorithm for one-dimensional multifractal signals (MFDMA). We observe that the correlation structure is the main source of multifractality, while heavy-tailed distribution plays a minor role in generating the multifractal effects. Our work also reveals that rotation period of stars is inherently scaled by degree of multifractality. As a result, analyzing the multifractal degree of referred series, we uncover an evolution of multifractality from shorter to larger periods.