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Bisector Velocities of Hα in the roAp Star α Cir: Probing the Principal Pulsation Mode

Published online by Cambridge University Press:  08 February 2017

I. K. Baldry
Affiliation:
Chatterton Astronomy Dept, School of Physics, University of Sydney, NSW 2006, Australia
T. R. Bedding
Affiliation:
Chatterton Astronomy Dept, School of Physics, University of Sydney, NSW 2006, Australia
M. Viskum
Affiliation:
Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark
H. Kjeldsen
Affiliation:
Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark Theoretical Astrophysics Center, University of Aarhus
S. Frandsen
Affiliation:
Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark

Extract

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α Circini is the brightest of the known rapidly oscillating Ap (roAp) stars. Previous observations of this star in photometry (Kurtz et al. 1994) have shown that it has one dominant pulsation mode, which is a pure oblique dipole mode (ℓ = 1) with a frequency of 2442 μHz (P = 6.825 min). Kurtz et al. (1994) measured the amplitude of the principal mode to be 2.55 mmag (Strömgren v).

Type
V. Asteroseismology I
Copyright
Copyright © Kluwer 1998 

References

Baldry, I.K., Bedding, T.R., Viskum, M., Kjeldsen, H. & Frandsen, S. (1997), Spectroscopy of the roAp star α Cir. I. Velocities of Hα and metal lines. MNRAS, in press.CrossRefGoogle Scholar
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