Non-radial pulsation, rotation and outburst in the Be star omega Orionis from the MuSiCoS 1998 campaign
Non-radial pulsation, rotation and outburst in the Be star omega Orionis from the MuSiCoS 1998 campaign
复制标题
MuSiCoS 1998 年活动中 Be 星 omega Orionis 的非径向脉动、旋转和爆发
DOI：
10.1051/0004-6361:20020522
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
J. Zorec
中科院分区：
文献类型：
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作者：
C. Neiner;A. Hubert;M. Floquet;S. Jankov;H. Henrichs;B. Foing;Joana M. Oliveira;S. Orlando;J. Abbott;I. Baldry;T. Bedding;J. Cami;H. Cao;C. Català;K. Cheng;A. D. D. Souza;E. Janot;J. Hao;L. Kaper;A. Kaufer;N. Leister;J. Neff;S. O’Toole;D. Schäfer;S. Smartt;O. Stahl;J. Telting;S. Tubbesing;J. Zorec
猎户座w（HD 37490，HR 1934）是一颗已知存在变星的Be星星。为了研究其短期和中期变化的性质和起源，对几条谱线进行了研究（Ha，Hδ，HeI 4471，4713，4921，5876，6678，CII 4267，6578，6583，MgII 4481，SiIII 4553和Sill 6347），根据1998年11月至12月MuSiCoS（多地点连续光谱学）活动期间连续22个晚上用8台望远镜拍摄的249个高信噪比高分辨率光谱。恒星参数的重新审视和投影的旋转速度（v sin i = 179 kms - 1）使用几种方法重新确定。使用MuSiCoS 98数据集，使用限制性局部清洁（RLC）算法和最小二乘法执行线轮廓变化（LPV）的时间序列分析。分析了几条谱线的质心速度、等效宽度和视vsini的行为，以及受辐射影响的光球谱线（He I红谱线，Sill 6347，CII 6578，6583）的紫色和红色分量。非径向脉动（NRP）模型使用相图和傅立叶多普勒成像（FDI）方法进行检查。LPV与NRP模式一致，l = 2或3，λ m = 2，频率为1.03 cd - 1。结果表明，发射线的突出发生在中期的活动。提出了两种方案来解释致密云的行为，暂时围绕星星的频率为0.46 cd - 1，在有关的爆发。
w Ori (HD 37490, HR 1934) is a Be star known to have presented variations. In order to investigate the nature and origin of its short-term and mid-term variability, a study is performed of several spectral lines (Ha, Hδ, HeI 4471, 4713, 4921, 5876, 6678, CII 4267, 6578, 6583, MgII 4481, SiIII 4553 and Sill 6347), based on 249 high signal-to-noise high-resolution spectra taken with 8 telescopes over 22 consecutive nights during the MuSiCoS (Multi Site Continuous Spectroscopy) campaign in November-December 1998. The stellar parameters are revisited and the projected rotational velocity (v sin i = 179 kms - 1 ) is redetermined using several methods. With the MuSiCoS 98 dataset, a time series analysis of line-profile variations (LPVs) is performed using the Restricted Local Cleanest (RLC) algorithm and a least squares method. The behaviour of the velocity of the centroid of the lines, the equivalent widths and the apparent vsini for several lines, as well as Violet and Red components of photospheric lines affected by emission (red He I lines, Sill 6347, CII 6578, 6583) are analyzed. The non-radial pulsation (NRP) model is examined using phase diagrams and the Fourier-Doppler Imaging (FDI) method. The LPVs are consistent with a NRP mode with l = 2 or 3, ‖m‖ = 2 with frequency 1.03 cd - 1 . It is shown that an emission line outburst occurred in the middle of the campaign. Two scenarios are proposed to explain the behaviour of a dense cloud, temporarily orbiting around the star with a frequency 0.46 cd - 1 , in relation to the outburst.