Nonlinear Analysis of Variable Stars

Colm Hall


This project was split into two parts. The first part was the writing of a manual for the operation of the Wooster observatory. This manual covers the software and hardware inside the observatory. It also describes how to operate the LX200 telescope, CCD, and Stellarium software. These three components, when used in conjunction, allow the user to take data on objects in the night sky paving the way for future astrophotometry at The College of Wooster.

The second part of this project was the analysis of stellar light curves for the variable stars RS Cygnus, RS Lacertae, U Perseus, and SW Virginis, provided by Dr. Robert Cadmus Jr. of Grinnell College. After converting the differential magnitudes to flux ratios, we favorably compared their Fourier transforms to their Lomb-Scargle periodograms. We then constructed simple systems of nonlinear differential equation to model these pulsating stars using Mathematica to adjust several parameters. We linearly related the simple models to the corresponding stellar fluxes.