Modeling Binary Central Stars in Planetary Nebulae

Primary Submission Contact

Hannah Rotter

Faculty Sponsor

Todd Hillwig

Faculty Sponsor Email Address



Arts and Sciences


Physics and Astronomy

Document Type

Oral Presentation


Fall 9-12-2014


When a star like our Sun dies it swells into a red giant and then expels its outer layers to form a planetary nebula surrounding the remaining core of the star. The outer layers then disperse into space leaving the core of the star behind as a white dwarf. The cause of many exotic shapes in planetary nebulae is unknown. However, it is thought that binary stars may play a role in the shaping process. In this project we are searching for binary central stars in planetary nebulae by detecting variations in brightness of the central star. By modeling discovered binary star systems, the resulting parameters will give insight into how the binary central star interacts with its surrounding nebula. We are especially focusing on a particular star, PHR J1602-4127, which was found to be a binary star and has a orbital period of 0.29592 days (7.102 hours). We have differential brightness data (observed with the SARA-South Telescope) in the green (V), red (R), and blue (B) filters and spectra (obtained with the Gemini-South Telescope). Using a binary star modeling program we have found possible parameter sets for physical values of this binary central star.

Biographical Information about Author(s)

Hannah Rotter is a senior physics major at Valparaiso University. This is her third summer working on astronomy research here on campus and her second summer working on this particular project with Dr. Hillwig. After graduation she hopes to continue her studies in astronomy and astrophysics in graduate school.

This document is currently not available here.