An asteroseismic study of the O9V star HD46202 from CoRoT space-based photometry

被引：73

作者：

Briquet, M. ^{[1
]}

Aerts, C. ^{[1
,2
]}

Baglin, A. ^{[3
]}

Nieva, M. F. ^{[4
]}

Degroote, P. ^{[1
]}

Przybilla, N. ^{[5
,6
]}

Noels, A. ^{[7
]}

Schiller, F. ^{[5
,6
]}

Vuckovic, M. ^{[1
]}

Oreiro, R. ^{[1
]}

Smolders, K. ^{[1
]}

Auvergne, M. ^{[3
]}

Baudin, F. ^{[8
]}

Catala, C. ^{[3
]}

Michel, E. ^{[3
]}

Samadi, R. ^{[3
]}

机构：

[1] Katholieke Univ Leuven, Inst Sterrenkunde, B-3001 Louvain, Belgium

[2] Univ Nijmegen, Dept Astrophys, IMAPP, NL-6500 GL Nijmegen, Netherlands

[3] Univ Paris 07, Observ Paris, Univ Paris 06, LESIA,CNRS,UMR8109, F-92195 Meudon, France

[4] Max Planck Inst Astrophys, D-85741 Garching, Germany

[5] Univ Erlangen Nurnberg, Dr Karl Remeis Observ, D-96049 Bamberg, Germany

[6] Univ Erlangen Nurnberg, ECAP, D-96049 Bamberg, Germany

[7] Univ Liege, Inst Astrophys & Geophys, B-4000 Liege, Belgium

[8] Inst Astrophys Spatiale, F-91405 Orsay, France

来源：

ASTRONOMY & ASTROPHYSICS | 2011年 / 527卷

基金：

欧洲研究理事会;

关键词：

asteroseismology; stars: oscillations; stars: variables: general; stars: early-type; stars: individual: HD 46202; BETA-CEPHEI STAR; LINE-PROFILE VARIATIONS; NONRADIAL PULSATIONS; O STARS; VARIABILITY; EVOLUTION; OPHIUCHI; WIND;

D O I：

10.1051/0004-6361/201015690

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The O9V star HD46202, which is a member of the young open cluster NGC 2244, was observed by the CoRoT satellite in October/November 2008 during a short run of 34 days. From the very high-precision light curve, we clearly detect beta Cep-like pulsation frequencies with amplitudes of similar to 0.1 mmag and below. A comparison with stellar models was performed using a chi(2) as a measure for the goodness-of-fit between the observed and theoretically computed frequencies. The physical parameters of our best-fitting models are compatible with the ones deduced spectroscopically. A core overshooting parameter alpha(ov) = 0.10 +/- 0.05 pressure scale height is required. None of the observed frequencies are theoretically excited with the input physics used in our study. More theoretical work is thus needed to overcome this shortcoming in how we understand the excitation mechanism of pulsation modes in such a massive star. A similar excitation problem has also been encountered for certain pulsation modes in beta Cep stars recently modelled asteroseismically.

引用

页数：8