Astronomy Seminar
Date/Time: | Friday, 02 Oct 2015 at 4:10 pm |
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Location: | 3 Physics |
Contact: | Steve Kawaler, Physics and Astronomy |
Phone: | 515-294-5440 |
Channel: | College of Liberal Arts and Sciences |
Categories: | Lectures |
Actions: | Download iCal/vCal | Email Reminder |
Convection in Sun-like stars manifests itself as absorption line asymmetries caused by differing amounts and temperatures of upwelling and downwelling gas. However, similar line asymmetries have never been observed or reported in much hotter stars. My study analyzes twelve unblended Fe II lines from the spectrum of HD 175156, a B-5 II star, using the line-bisector method of Gray (1992) and confirms the existence of asymmetries caused by the downwelling gas, similar to observations of spectral absorption line asymmetry for Sun-like stars. The observed spectral line asymmetry can be approximated by a two-stream model using gaussian curves fit to the original absorption lines.