Simulating the photometric study of pulsating white dwarf stars in the physics laboratory

Abstract

We have designed a realistic simulation of astronomical observing using a relatively low-cost commercial CCD camera and a microcontroller-based circuit that drives LEDs inside a light-tight box with time-varying intensities. As part of a laboratory experiment, students can acquire sequences of images using the camera, and then perform data analysis using a language such as MATLAB or Python to: (a) extract the intensity of the imaged LEDs, (b) perform basic calibrations on the time-series data, and (c) convert their data into the frequency domain where they can then identify the frequency structure. The primary focus is on studying light curves produced by the pulsating white dwarf stars. The exercise provides an introduction to CCD observing, a framework for teaching concepts in numerical data analysis and Fourier techniques, and connections with the physics of white dwarf stars.