The detection of the rich p-mode spectrum and asteroseismology of Przybylski's star *
Astrophysical Research Center for the Structure and Evolution of the Cosmos, Sejong University, Seoul 143-747, Korea e-mail: email@example.com
2 Astronomical Observatory, Odessa National University, Shevchenko Park, Odessa, 65014, Ukraine
3 Thüringer Landessternwarte Tautenburg, Sternwarte 5, 07778, Tautenburg, Germany e-mail: firstname.lastname@example.org
4 Astronomical Institute, School of Science, Tohoku University, Sendai 980-8578, Japan e-mail: email@example.com
5 Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT, Australia e-mail: firstname.lastname@example.org
Accepted: 23 August 2008
Aims. We investigate the oscillation spectrum of the most chemically-peculiar star in the sky, the rapidly-oscillating magnetic (roAp) star HD 101065.
Methods. High-precision radial velocity (RV) measurements, spanning four consecutive nights on 3–6 March, 2004, were obtained with the HARPS echelle-spectrometer at the ESO 3.6-m telescope, and photometric data were acquired during 6 nights of observations at the 24-inch telescope of Siding Spring Observatory. The RVs were measured using all spectral lines in the wavelength range 4400–5100 Å.
Results. We detected a rich spectrum of oscillation modes with semi-amplitudes ranging between 217 m s-1 and 1.6 m s-1. These belong to the complete spectrum of high-order, low –2 modes, having a large spacing of Hz. We calculated the nonadiabatic frequencies of axisymmetric high-order p-modes for main-sequence models with dipole magnetic fields of two chemical compositions and . The former composition provided the best fit model and yielded stellar parameters of mass, , age = (1.5 ± 0.1) 109 yr, effective temperature , luminosity , surface gravity , and polar magnetic field strength, Bp = kG. We are able to identify the modes of all detected oscillation frequencies. The photometric U and B light curves have maxima that precede the RV maximum by 0.16–0.19 in phase.
Key words: stars: chemically peculiar / stars: oscillations / stars: individual: HD 101065
© ESO, 2008