中国物理B ›› 2011, Vol. 20 ›› Issue (9): 90601-090601.doi: 10.1088/1674-1056/20/9/090601
张继涛, 吴学健, 李岩
Zhang Ji-Tao(张继涛)†, Wu Xue-Jian(吴学健), and Li Yan(李岩)
摘要: To determine the Avogadro constant with a target relative uncertainty of 2 × 10-8, the uncertainty component of the silicon sphere's volume introduced by the spherical harmonics method, which is usually used in determining the sphere's volume, is reevaluated. By means of representing the shape of the silicon sphere by an ellipsoid with Gaussian white noise in its diameters, the uncertainty of the current mapping methods based on the spherical harmonics theory can be estimated theoretically. It is evidenced that the uncertainty component attributed to the current mapping method is underestimated. To eliminate this effect as much as possible, the number of mapping points should be increased to more than before. Moreover, a new mapping method is proposed to accomplish the equal-area mapping with large number points on the silicon sphere.
中图分类号: (Metrology)