Analysis of variability of TW Hya as observed by MOST and ASAS in 2009
Analysis of variability of TW Hya as observed by MOST and ASAS in 2009
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2009年MOST和ASAS观测到的TW Hya变异性分析
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
W. Weiss
中科院分区：
文献类型：
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作者：
M. Siwak;S. Rucinski;J. Matthews;G. Pojmański;R. Kuschnig;D. Guenther;A. Moffat;D. Sasselov;W. Weiss
作为我们在2007年和2008年的研究的延续，新的光度观测金牛座T星星TW Hya获得的MOST卫星和全天自动巡天（ASAS）项目在2009年超过40天的时间分辨率为0.2 d。对MOST-ASAS组合数据的小波分析提供了一幅丰富的连贯、间歇、可变周期振荡的图像，与2008年数据中发现的类似。周期（1.3-10 d）和系统的周期缩短的时间尺度为星期内的磁旋转控制的吸积过程中的吸积盘周围的星星的模型可以解释。在这个模型中，并根据假设的等离子体包裹的可见性引起的振荡，观察到的最短振荡周期可能表明恒星旋转周期为1.3或2.6 d，与光盘同步在4.5或7.1 R，分别。
As a continuation of our previous studies in 2007 and 2008, new photometric observations of the T Tauri star TW Hya obtained by the MOST satellite and the All Sky Automated Survey (ASAS) project over 40 d in 2009 with temporal resolution of 0.2 d are presented. A wavelet analysis of the combined MOST-ASAS data provides a rich picture of coherent, intermittent, variable-period oscillations, similarly as discovered in the 2008 data. The periods (1.3-10 d) and systematic period shortening on time-scales of weeks can be interpreted within the model of magnetorotationally controlled accretion processes in the inner accretion disc around the star. Within this model and depending on the assumed visibility of plasma parcels causing the oscillations, the observed shortest oscillation period may indicate the stellar rotation period of 1.3 or 2.6 d, synchronized with the disc at 4.5 or 7.1 R ⊙ , respectively.