Analysis of pulsating variable stars using the visibility graph algorithm

PLoS One. 2021 Nov 17;16(11):e0259735. doi: 10.1371/journal.pone.0259735. eCollection 2021.

Abstract

We study the light curves of pulsating variable stars using a complex network approach to build visibility graphs. We consider various types of variables stars (e.g., Cepheids, δ Scuti, RR Lyrae), build two types of graphs (the normal visibility graph (VG) and the horizontal visibility graph (HVG)), and calculate various metrics for the resulting networks. We find that all networks have a power-law degree distribution for the VG and an exponential distribution for the HVG, suggesting that it is a universal feature, regardless of the pulsation features. Metrics such as the average degree, the clustering coefficient and the transitivity coefficient, can distinguish between some star types. We also observe that the results are not strongly affected by the presence of observation gaps in the light curves. These findings suggest that the visibility graph algorithm may be a useful technique to study variability in stars.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms*
  • Cluster Analysis
  • Heart Rate / physiology
  • Humans

Grants and funding

This work has been financially supported by FONDECYT (https://www.conicyt.cl/fondecyt/), grant number 1201967 (VM). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.