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arXiv 0804.1182astro-ph
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用恒星技术研究太阳振荡的振幅

The amplitude of solar oscillations using stellar techniques

Hans Kjeldsen, Timothy R. Bedding, Torben Arentoft, R. Paul Butler, Thomas H. Dall, Christoffer Karoff, Laszlo L. Kiss, C. G. Tinney, William J. Chaplin

摘要:

类太阳振荡的振幅取决于激励和阻尼,这两者都是由对流控制的。因此,将观测结果与理论进行比较,应该会提高我们对潜在物理学的理解。然而,理论模型总是计算相对于太阳的振荡振幅,因此使用恒星技术对太阳振幅进行良好的校准至关重要。我们已经使用了白天的太阳光谱,获得与HARPS和UCLES,测量太阳振荡,并作出了详细的比较与观测使用的BiSON日震仪器。我们发现,平均太阳振幅测量使用恒星技术,平均超过一个完整的太阳周期,是18.7 +/- 0.7厘米/秒的最强的径向模式(l=0)和25.2 +/- 0.9厘米/秒的l=1。此外,我们使用模拟来建立一个方程,估计的不确定性的振幅测量是由其他恒星,鉴于模式寿命是已知的。最后,我们还给出了三颗恒星的类太阳振荡的振幅,我们从一系列的短期观测HARPS(伽马Ser,β Aql和α为),连同修订的振幅为其他五颗恒星,我们以前发表的结果(α Cen A,α Cen B,β Hyi,nu Ind和δ Pav)。

英文摘要:

The amplitudes of solar-like oscillations depend on the excitation and damping, both of which are controlled by convection. Comparing observations with theory should therefore improve our understanding of the underlying physics. However, theoretical models invariably compute oscillation amplitudes relative to the Sun, and it is therefore vital to have a good calibration of the solar amplitude using stellar techniques. We have used daytime spectra of the Sun, obtained with HARPS and UCLES, to measure the solar oscillations and made a detailed comparison with observations using the BiSON helioseismology instrument. We find that the mean solar amplitude measured using stellar techniques, averaged over one full solar cycle, is 18.7 +/- 0.7 cm/s for the strongest radial modes (l=0) and 25.2 +/- 0.9 cm/s for l=1. In addition, we use simulations to establish an equation that estimates the uncertainty of amplitude measurements that are made of other stars, given that the mode lifetime is known. Finally, we also give amplitudes of solar-like oscillations for three stars that we measured from a series of short observations with HARPS (gamma Ser, beta Aql and alpha For), together with revised amplitudes for five other stars for which we have previously published results (alpha Cen A, alpha Cen B, beta Hyi, nu Ind and delta Pav).

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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