The detection of the rich p-mode spectrum and asteroseismology of Przybylski's star
In: Astronomy and astrophysics (Berlin. Print), Jg. 490 (2008), Heft 3, S. 1109-1120
Online
academicJournal
- print, 1/2 p
Zugriff:
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 ℓ = 0-2 modes, having a large spacing of Av = 64.07 ± 0.9 μHz. We calculated the nonadiabatic frequencies of axisymmetric high-order p-modes for main-sequence models with dipole magnetic fields of two chemical compositions (X,Z) = (0.7,0.02) and (X,Z) = (0.695,0.025). The former composition provided the best fit model and yielded stellar parameters of mass, M = 1.525 ± 0.025 M⊙, age = (1.5 ± 0.1) x 109 yr, effective temperature log Te = 3.821 ± 0.006, luminosity log L/L⊙ = 0.797 ± 0.026, surface gravity log g = 4.06 ± 0.04, and polar magnetic field strength, Bp = 8.7 ± 0.3 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.
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The detection of the rich p-mode spectrum and asteroseismology of Przybylski's star
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Autor/in / Beteiligte Person: | MKRTICHIAN, D. E ; HATZES, A. P ; SAIO, H ; SHOBBROOK, R. R |
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Zeitschrift: | Astronomy and astrophysics (Berlin. Print), Jg. 490 (2008), Heft 3, S. 1109-1120 |
Veröffentlichung: | Les Ulis: EDP Sciences, 2008 |
Medientyp: | academicJournal |
Umfang: | print, 1/2 p |
ISSN: | 0004-6361 (print) |
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