A Galactic Survey of Dusty Wolf-Rayet Stars in the X-Ray
Faculty Mentor Name
Pragati Pradhan, Noel Richardson
Format Preference
Poster
Abstract
Wolf-Rayet (WR) stars are massive stars in late-stage evolution that have lost their outer hydrogen envelopes and have high mass-loss rates. WR stars could be one of the first dust-producers in the universe. We will examine observations of Galactic dust-producing systems, determining the conditions which dust can form, i.e. does the dust production require a companion? It is unknown if WRs could produce dust independently; some dusty WR stars have appeared single in studies thus far. The majority of known WR stars are found near the Galactic center, which contains an abundance of dust and particles that scatter light. X-ray wavelengths do not get obstructed as much as Infrared from the dust, allowing for more stars to be surveyed without major interference. At present, it is still a matter of great debate how X-ray radiation is produced in WR stars, albeit there are some promising research avenues, such as the presence of Co-rotating Interaction regions in the winds of single WR stars. For binary stars on the other hand, the formation of shocks when the winds of two stars collide can generate higher temperatures. To fully understand WR stars, we need to unravel mechanisms of X-ray production in their wind. We have created a source list of WR stars to examine, debugged and updated an automated stellar reduction software, and will continue to progress to our goal by executing the code on the archival NASA data to explore the light curve variability in relation to time. Mapping the X-ray luminosity over time can tell us if these sources have strong collisions from less-evolved O or B star companions, which still have a strong wind. Then, we will model X-ray spectra with models to measure the absorption, flux, and other spectral parameters. To the best of our knowledge, this is the first systematic survey of WR stars in the X-ray.
A Galactic Survey of Dusty Wolf-Rayet Stars in the X-Ray
Wolf-Rayet (WR) stars are massive stars in late-stage evolution that have lost their outer hydrogen envelopes and have high mass-loss rates. WR stars could be one of the first dust-producers in the universe. We will examine observations of Galactic dust-producing systems, determining the conditions which dust can form, i.e. does the dust production require a companion? It is unknown if WRs could produce dust independently; some dusty WR stars have appeared single in studies thus far. The majority of known WR stars are found near the Galactic center, which contains an abundance of dust and particles that scatter light. X-ray wavelengths do not get obstructed as much as Infrared from the dust, allowing for more stars to be surveyed without major interference. At present, it is still a matter of great debate how X-ray radiation is produced in WR stars, albeit there are some promising research avenues, such as the presence of Co-rotating Interaction regions in the winds of single WR stars. For binary stars on the other hand, the formation of shocks when the winds of two stars collide can generate higher temperatures. To fully understand WR stars, we need to unravel mechanisms of X-ray production in their wind. We have created a source list of WR stars to examine, debugged and updated an automated stellar reduction software, and will continue to progress to our goal by executing the code on the archival NASA data to explore the light curve variability in relation to time. Mapping the X-ray luminosity over time can tell us if these sources have strong collisions from less-evolved O or B star companions, which still have a strong wind. Then, we will model X-ray spectra with models to measure the absorption, flux, and other spectral parameters. To the best of our knowledge, this is the first systematic survey of WR stars in the X-ray.