Spectroscopy and Interferometry of the Winds of Luminous Blue Variables

• Main Author: Richardson, Noel D
• Format: Others
• Published: Digital Archive @ GSU 2012
• Online Access: http://digitalarchive.gsu.edu/phy_astr_diss/52; http://digitalarchive.gsu.edu/cgi/viewcontent.cgi?article=1051&context=phy_astr_diss

Massive stars are rare, but emit most of the light we observe in the Universe and create many of the heavy elements. New observational approaches and long time-series are utilized in order to examine the basic observable properties of the stars and the mass lost during their lifetimes. In order to study the winds and the long-term changes of the stars, hot stars with some of the strongest winds (the luminous blue variables) were studied in detail with optical spectroscopy and photometry. A 25-year survey on the prototype P Cygni is presented, where the long-term changes are documented for many parameters that have not been examined before. In addition, we present a detailed study of the H-band emitting region through interferometric imaging with the CHARA Array as well as spectrophotometry. A detailed study of the Hα line variability of the LBV η Carinae near its recent periastron is presented. The LBV candidate HDE 326823 is found to be a binary system with variability driven by the close binary companion and Roche lobe overflow. Finally, I present a three-year study of many LBVs in the Milky Way Galaxy and Magellanic Clouds for a statistically significant survey of the long-term variability properties of these rare stars as a population. Future studies of LBV winds are outlined, as well as a short discussion of Georgia State University’s Hard Labor Creek Observatory for these types of studies.