22nd Annual Student Research Conference
Searching for Chaos in a Mira-type Variable Star
Amanda F. Tougas
Dr. Matthew M. Beaky, Faculty Mentor
Red giant stars are pulsating, unstable variable stars with irregular light curves. Since these stars change brightness over time, astrophysicists use time series analysis to determine their physical properties. To represent variable stars with irregular light curves, nonlinear time series analysis is used, which is associated with chaos theory. In this project, we investigated U Cyg, a pulsating Mira-type variable star. Over 100 years of U Cyg photometric data were obtained from the American Association of Variable Star Observers. We conducted a standard linear analysis to explore the limitations of this method. Next, a nonlinear analysis was conducted to search for chaotic behavior in the light curve of U Cyg. From the nonlinear analysis, we obtained phase space projections, determined the Lyapunov exponent, and created synthetic light curves to represent the U Cyg data. The results indicate the presence of chaotic behavior in the irregular light curve of U Cyg.
Keywords: Chaos, Variable Stars, U Cyg, Nonlinear Time Series Analysis
Topic(s):Physics
Mathematics
Presentation Type: Oral Paper
Session: 38-2
Location: VH 1412
Time: 1:30