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H alpha Periodicities in the Spectrum of Alpha Cygni. Noel Richardson The University of Toledo Advisor: Dr. Morrison. Some Interesting Facts about Alpha Cygni. Type A2Iae. Luminosity is 160000 times that of the Sun. Diameter: 180 solar (measured) 200 solar (calculated).
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H alpha Periodicities in the Spectrum of Alpha Cygni Noel Richardson The University of Toledo Advisor: Dr. Morrison
Some Interesting Facts about Alpha Cygni Type A2Iae Luminosity is 160000 times that of the Sun Diameter: 180 solar (measured) 200 solar (calculated) Approximately 2600 light years away If placed at the distance of Vega, it would be as bright as a well developed crescent moon.
How to find Alpha Cygni Right Ascension: 20h 41m 29s Declination: +45 17' 09" epoch: 2001.5
The Spectrum of Alpha Cygni Shows a weak P Cygni profile, which signifies mass loss Estimated mass loss is 0.8 millionths of a solar mass each year Spectrum is slightly variable
Our project Look at spectra taken at Ritter Observatory Create a dynamical spectrum to look for periodicities in the H alpha region of the spectrum.
Telluric Lines Absorption features produced by the Earth's Atmosphere
Removal of Telluric Lines Use a hot rapidly rotating star, such as sigma Sagittarii or zeta Aquilae
IRAF allowed us to fit Gaussian curves to the telluric lines. Normalized Flux
Then, IRAF constructed an artificial spectrum that was a telluric standard.
With the IRAF task telluric, the spectra are divided by a telluric template, removing the unwanted absorption features.
Finally, the continuum of the spectra is normalized so that all the spectra are easy to compare.
A look at an absorption event Several Events took place in the 2001 observing season June 9 These were not the only spectrum changes, but the ones with the most data points. September 6 November 1
These spectra will be combined into a dynamical spectrum. This is a dynamical spectrum for the 1997 observing season.
Conclusions Events occur approximately every 40 days Not all events are the same. Spiral shaped density enhancements in the stellar wind More data needed
Acknowledgments Dr. Nancy Morrison Chris Mulliss David Knauth and John Wisniewski Ritter Observing Team