一个新的变振幅和周期的自由核章动模型
A New Free Core Nutation Model with Variable Amplitude and Period
摘要：
在戈达德空间飞行中心、应用天文研究所和美国海军天文台获得的三个最长和最密集的VLBI章动序列被用来研究自由核心章动（FCN）对天极偏移的贡献。最近的一些研究表明，FCN周期或相位并不是恒定不变的，而是在相当大的范围内变化，约为410- 490天（对于等效周期）。为了在实际中实现这一结果，一个新的FCN模型与可变的振幅和周期（相位）的发展。该模型与观测结果的比较表明，比现有的协议。在对VLBI章动观测序列与IAU 2000 A模式的差异进行修正后，它们减小到约100微弧秒的水平。
英文摘要：
Three most long and dense VLBI nutation series obtained at the Goddard Space Flight Center, Institute of Applied Astronomy, and U.S. Naval Observatory were used for investigation of the Free Core Nutation (FCN) contribution to the celestial pole offset. Some recent studies have showed that the FCN period or/and phase does not remain constant, but varies in a rather wide range of about 410--490 days (for equivalent period). To implement this result in the practice, a new FCN model with variable amplitude and period (phase) is developed. Comparison of this model with observations shows better agreement than existing one. After correction of the differences between observed VLBI nutation series and the IAU2000A model, they decreased to a level about 100 microarcseconds.
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。
