Devin Chu was born in Los Angeles, California, and moved to Hilo when he was two years old. He graduated as valedictorian from Hilo High School, and this fall he will enter his sophomore year at Dartmouth College in Hanover, New Hampshire. Devin plans to major in astronomy (his interest since childhood) and minor in history. After finishing his undergraduate education, Devin intends to complete a doctoral degree in astronomy and hopes to return to Hilo as a research astronomer.
In his free time, Devin enjoys cycling, watching sports, and socializing with friends.
Institution when accepted: Dartmouth College in Hanover, New Hampshire
Akamai Project:Â Â Asteroseismology of White Dwarf GD 358Â Using Optical and Ultraviolet Light Curves
Project Site:Â Â Gemini Observatory
Mentors: Atsuko Nitta & Scot Kleinman
Project Abstract:
Asteroseismology is the study of the internal structure of stars. Similar to the way seismologists use the Earth’s vibrations during an earthquake to draw conclusions about the Earth’s inner structure, astronomers analyze a pulsating star’s light curve — the intensity of the light over time — to characterize its internal structure. Pulsating white dwarf stars are ideal for asteroseismology because they have relatively simple structures that make them easier to model than other stars. Asteroseismology relies on accurately identifying the pulsation modes that are simultaneously present as a star vibrates. The goal of this project is to attempt to identify pulsation modes via the “chromatic amplitude method.” The pulsating white dwarf GD 358 was observed simultaneously in the ultraviolet using the Hubble Space Telescope (HST) and in the optical by the Whole Earth Telescope (WET), a network of telescopes around the world that enable an object to be observed continuously for many days. Light-curve amplitudes will be extracted from both the ultraviolet and optical data, and the ratios of amplitudes at different wavelengths will be found. Based on these ratios, the modes of GD 358 can be identified. The identified modes will be compared to the modes found by previous studies using the “period method,” an analysis of the distribution of periods present in a single-color light curve. If the chromatic amplitude method accurately identifies previously known modes of GD 358, it will serve as a confirmation of a powerful new method for asteroseismology, especially useful for stars with sparse modes that are difficult to analyze via the period method alone.