Precise rotation rates for five slowly rotating A stars

Journal Article · Tue Apr 01 00:00:00 EDT 2014 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.1088/0004-6256/147/4/81· OSTI ID:22340309

Gray, David F., E-mail: [e-mail] ^[1]

---

1. Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)

Projected rotation rates of five early A-type slowly rotating stars are measured spectroscopically to a precision of 0.2 km s{sup –1}. A detailed Fourier analysis is done, as well as a comparison of profiles directly. Macroturbulence is needed in addition to rotation to reproduce the profile shapes. An upper limit of ≲2 km s{sup –1} is placed on the microturbulence dispersion. Small unexplained differences between the models and the observations are seen in the sidelobe structure of the transforms. The v sin i results are: α Dra, 26.2; θ Leo, 22.5; α CMa A, 16.7; γ Gem A, 10.7; o Peg, 6.0 km s{sup –1}. These stars are suitable as standards for measuring rotation using less fundamental methods.

• OSTI ID: 22340309
• Journal Information: Astronomical Journal (New York, N.Y. Online), Vol. 147, Issue 4; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCURACY
ATMOSPHERES
COMPARATIVE EVALUATIONS
DISPERSIONS
FOURIER ANALYSIS
ROTATION
SPECTROSCOPY
STARS
TURBULENCE