摘要
本文利用1987年1月-1989年3月的LLR资料解算了UT0-UTC序列,在归算中分别应用了Eckhafdt-500和LLB200两个天平动模型,以便分析和比较它们对解算UT0的影响。结果表明两个天平动模型间存在着明显的系统差。它反映在两者的事前残差中,最大差值可达100ns,这就使得用Eckhardt-500天平动模型的事前残差解算得到的UT0-UTC序列对IERS的平均偏离比采用LLB 200天平动模型时要大1ms,但对两结果序列的外部精度没有影响。用事后残差解算,系统差的影响减小了,确定的UT0-UTC序列更靠近IERS系统,用两种天平动模型解算的UT0-UTC结果也更接近,外部精度也几乎一样且比用事前残差解的结果略好。
The values of UTO-UTC were determined from global data of Lunar Laser Ranging during Jan. 1987 to Mar. 1989. The lunar libration models Eckhardt(?)00 and LLB200, were used in the data processing in order 'to analyse the effect of lunar libration models on UTO determination. It is shown that there is a obvious systematic deviation between two libration models. A maximum difference value of more than 100ns, which is reflected as systematic trend in their pre-residuals exists.
Both LLR UTO-UTC series were derived from pre-residuals. which were computed by Eckhardt-500 and LLB200 Libration models. The average deviation referred to IERS series are 2.5ns and 1.5ns, respectively, but both external precisions are same.
Using the post-residuals, the systematic errors of UTO-UTC are decreased so that the results obtained with two libration models are closer each other and also approximate the values of the IERS system. Their external precisions are almost same. It is slight better than that computed from pre-residual.
出处
《中国科学院上海天文台年刊》
1991年第12期5-13,共9页
Annals Shanghai Astronomical Observatory Chinese Academy of Sciences
