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DAVID F. GRAY

Observatory Director, Professor of Astronomy

Ph.D. (Michigan), M.S. (Michigan), B.S. (Wisconsin)

Department of Physics & Astronomy
University of Western Ontario
London, Ontario N6A 3K7
Canada

E-mail: dfgray@ uwo.ca
Phone: (519) 661-2111 extension 86715
Fax: (519) 661-2033

Office: 316 Physics-Astronomy Building

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Elginfield Observatory Telescope

Good News: The third edition of The Observation and Analysis of Stellar Photospheres, (Cambridge University Press) is now available. The basic layout of the third edition mimics the second edition; there are many improvements and updates, some new figures, and exercises. An error list is being compiled.

For those of you who do not know the book, it shows how we measure the physical properties of stars, such as radii, temperatures, chemical composition, motions in stellar atmospheres, and rotation rates, through analysis of the starlight. Analysis tools include spectrographs, radiation transfer, model photospheres, and the behavior of both the continuous spectrum and spectral lines. There are many interesting diagrams and useful tables. The book is suited for advanced undergraduate course, first-year graduate work, or as a useful manual and reference for the researcher.

Research Interests & Publications

• Rotation of stars, magnetic braking, angular momentum evolution, differential rotation, rotational modulation
• Magnetic cycles in stars, variations in power output, global warming, chromospheric activity, dynamo processes
• Stellar granulation and velocity fields in stellar atmospheres, variations during stellar cycles and across the H-R diagram
• Surface features on stars, including starspots and starpatches
• Zeeman Broadening of spectral lines and the measurement of stellar magnetic fields
• Fourier analysis of spectral lines
• Temperatures, basic properties of stars, including measurements of radii, and surface gravities.
• 51 Peg, oscillations, and precise radial velocity measurements
• Spectrographs and other instrumentation

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Special References of Interest

• "Rotation of Evolved Stars," in Angular Momentum Evolution of Young Stars, 1991, (Kluwer: Dordrecht), S. Catalano and J.R. Stauffer, eds.
• "Stellar Magnetic-Cycle Phasing," Pub. Astron. Soc. Pacific 106, 145, 1994.
• Lectures on Spectral-Line Analysis: F, G, and K Stars, (The Publisher: Arva, Ontario; available from author), 1988.
• The Observation and Analysis of Stellar Photospheres, (Cambridge: Cambridge), 2^nd ed., 1992. Correction list is available.

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Observatories at Western

The Elginfield Observatory, located 25 km north of London, is the main research installation.

On the Campus, we have the Cronyn Observatory. That's where student labs are done, and that's where the Open House/Public Night activities are held.

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The Astronomy Group also has a home page.

So does the University of Western Ontario.

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