Precise radial-velocity measurements of 4 G-type giants, 11 Com, ζ Hya, ∈ Tau, and η Her, were carried out. Short-term variations with amplitudes of 1-7 m s~(-1) and periods of 3-1 Ohr were detected. A period analysis shows that the individual power distribution has a Gaussian shape, and that their peak frequencies (v_(max)) are in a good agreement with a prediction by the scaling law. With using a pre-whitening procedure, significant frequency peaks of more than 3 σ were extracted for these giants. From these peaks, we determined the large frequency separation by constructing the highest peak distribution of the collapsed power spectrum, which is also in good agreement with what the scaling law for the large separation predicts. Echelle diagrams of the oscillation frequency were created based on the extracted large separations, which is very useful to clarify the properties of the oscillation modes. In these echelle diagrams, odd-even mode sequences are clearly seen. Therefore, it is certain that in these G-type giants, non-radial modes are detected in addition to the radial mode. As a consequence, these properties of oscillation modes are shown to follow what Dziembowski et al. (2001, MNRAS, 328, 601) and Dupret et al. (2009, A&A, 506, 57) theoretically predicted. The damping times for these giants were estimated with the same method as that developed by Stello et al. (2004, Sol. Phys., 220, 207). The relation of the Q-value (ratio of damping time to period) to the period was discussed by adding data of other stars, ranging from dwarfs to giants.
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机译：对4个G型巨人11 Com，ζHya，εTau和ηHer进行了精确的径向速度测量。检测到振幅为1-7 m s〜（-1）和周期为3-1 Ohr的短期变化。周期分析表明，单个功率分布具有高斯形状，并且其峰值频率（v_（max））与缩放定律的预测非常吻合。通过使用预增白程序，可以为这些巨人提取大于3σ的显着频率峰值。从这些峰中，我们通过构建折叠功率谱的最高峰分布来确定大的频率分离，这也与大分离的缩放定律所预测的一致。基于提取的大间隔创建了振荡频率的Echelle图，这对于阐明振荡模式的特性非常有用。在这些阶梯图中，可以清楚地看到奇偶模式序列。因此，可以肯定的是，在这些G型巨人中，除了径向模式之外，还检测到非径向模式。结果，振荡模式的这些特性显示出遵循Dziembowski等人的观点。 （2001，MNRAS，328，601）和Dupret等。 （2009，A＆A，506，57）从理论上进行预测。用与Stello等人开发的方法相同的方法估算这些巨人的阻尼时间。 （2004，Sol.Phys。，220，207）。 Q值（阻尼时间与周期的比率）与周期的关系通过添加从矮人到巨星等其他恒星的数据进行了讨论。
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