The Birmingham Solar-Oscillations Network (BiSON) has been collecting data for over 30yrs and so observations span nearly three 11yr solar activity cycles. This allows us to address important questions concerning the solar cycle and its effect on solar oscillations, such as: how consistent is the acoustic behaviour from one cycle to the next? We have used the p-mode frequencies observed in BiSON data from one solar activity cycle (cycle 22) to predict the mode frequencies that were observed in the next activity cycle (cycle 23). Some bias in the predicted frequencies was observed when short 108d time series were used to make the predictions. We also found that the accuracy of the predictions was dependent on which activity proxy was used to make the predictions and on the length of the relevant time series.
Variations of the Solar Acoustic High-Degree Mode Frequencies over Solar Cycle 23
利用太阳和日光层天文台（SOHO）航天器上的迈克尔逊多普勒成像仪（MDI）获得的全圆盘观测结果，我们提出了太阳活动周期引起的太阳声学模式频率的变化。在第23太阳活动周的大部分时间里，利用全球日震学分析技术对高阶（100 < l < 900）太阳声模进行了分析。我们遵循Korzennik，Rabello-Soares和Schou（2004）中详细描述的方法来推断高阶模态参数的无偏估计（另见Rabello-Soares，Korzennik和Schou，2006）。我们已经排除了大多数已知的影响高阶模的仪器效应和观测效应。我们发现，高度的变化是在良好的协议与中等程度的结果，除了几年时，仪器高度散焦。分析和讨论了离焦对高阶估计的影响。我们的结果为高次模式证实，频率偏移标度的相对模式惯性是一个函数的频率和它是独立的程度。
We have obtained empirical relations between the p-mode frequency shift and the change in solar activity indices. The empirical relations are determined on the basis of frequencies obtained from BBSO and GONG stations during solar cycle 22. These relations are applied to estimate the change in mean frequency for the cycle 21 and 23. A remarkable agreement between the calculated and observed frequency shifts for the ascending phase of cycle 23 indicates that the derived relations are independent of epoch and do not change significantly from cycle to cycle. We propose that these relations could …
Analysis of the solar cycle and core rotation using 15 years of Mark-I observations:1984-1999. I. The solar cycle
使用太阳分光光度计Mark-I对几乎两个完整的太阳周期进行了高质量的低阶声学模式（p模式）观测，该分光光度计位于Observatorio del Teide（西班牙特内里费岛），现在作为伯明翰太阳振荡网络（BiSON）的一部分运行。我们已经进行了傅立叶分析的30个校准的时间序列的一年的持续时间，涵盖了1984年和1999年之间的15年。应用不同的技术产生的功率谱，我们研究了太阳活动变化的签名上的低度p-模式。我们发现，中心频率的变化和总速度功率（TVP）的变化。提出了一种新的同步拟合方法，并对频移的频率依赖性进行了研究。结果证实了约450 nHz，峰-峰，平均为2.5和3.7 mHz之间的低度模式的声学模式的中心频率的变化。TVP与太阳活动指数呈反相关，在第22周的最小值和最大值之间下降约20%。的结果进行了比较，获得的中间程度，使用LOWL数据。频移被发现增加的程度与弱的l-依赖类似的反模式质量。这证实了早先关于近地表效应占主导地位的建议。
We report on the changes of the Sun's subsurface stratification inferred from helioseismology data. Using SOHO/MDI (SOlar and Heliospheric Observatory/Michelson Doppler Imager) data for the last 9 years and, more precisely, the temporal variation of f-mode frequencies, we have computed the variation of the radius of subsurface layers of the Sun by applying helioseismic inversions. We have found a variability of the ``helioseismic'' radius in antiphase with the solar activity, with the strongest variations of the stratification being just below the surface around 0.995$R_{\odot}$. Besides, the …
