关于仪器比较中墩差测定的讨论

On the measurement of geomagnetic field difference at different piers for instrumental comparison

精密测定地磁台观测室内的墩位差，它对于统一标准、仪器比较、验收仪器，实现观测工作正常化，标准化至关重要。地磁组于１９９３～１９９６年在北京台３＃与５＃观测墩上，连续４年使用Ｇ８５６质子旋进式磁力仪测定地磁总强度Ｆ２１次，笔者对７７４个数据进行了统计，其结果是，３＃与５＃墩之差值ΔＦＢ（３－５）＝－３．５７ｎＴ，标准偏差ＳＦ＝±０．４５ｎＴ。并对墩差的测量方法、复测次数、以及数列与数据组的选择进行了有益的讨论。

It is very important accurately to determine the geomagnetic field difference at different piers in the absolute observation house at a geomagnetic observatory. It will help us to establish a standard, to make instrumental comparison, to check new instrument before acceptance, and even more to bring about normalization and standardization in observation works. The measurement of geomagnetic total intensity F was made 21 times from the year 1993 to the year 1996 at the piers No.3 and No.5 in the absolute observation house at Beijing Geomagnetic Observatory with the proton precession magnetometer of G856 by the Technological Leading Group of the Chinese Geomagnetic Observatory Network. The statistical analysis on the 774 data points revealed that the geomagnetic field difference at the two piers is Δ F B (3-5) =-3.57 nT with the standard deviation of S F =±0.45 nT. More useful discussion was made on the observation method and on how many times to measure and how to choose the useful data points.