This report describes the first CCM key comparison of realizations of the kilogram definition based on the fixed numerical value of the Planck constant, which came into force on 20 May 2019. The objectives were to determine the level of agreement between realizations of the kilogram using Kibble and joule balances and the X-ray crystal density (XRCD) method and to provide input for the calculation of the first "consensus value" of the kilogram. The consensus value will serve as the basis for an internationally coordinated dissemination of the kilogram which will continue until sufficient agreement between realization experiments has been achieved.The comparison was organized by the BIPM and had seven participants. The BIPM, KRISS, NIST and NRC operated Kibble balances, the NIM used a joule balance and the NMIJ and the PTB participated using 28Si spheres, the masses of which were determined with the XRCD method. These realization methods were used to calibrate 1 kg mass standards under vacuum. The standards were sent (in air) to the BIPM where they were compared under vacuum with each other and with BIPM Pt-Ir working standards. The latter were calibrated (in air) traceable to the International Prototype of the Kilogram (IPK), the mass of which served as the definition of the kilogram until 20 May 2019.The results of the weighings at the BIPM together with the measurement results communicated by the participants allowed comparison of the values attributed to mass standards of 1 kg using the participating realization experiments. The level of agreement between mass determinations with the realization experiments and the BIPM as-maintained mass unit, traceable to the Planck constant through the mass of the International Prototype of the Kilogram can also be deduced.Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

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千克实现的 CCM 关键比较报告 CCM.M-K8.2019

本报告描述了基于普朗克常数的固定数值的千克定义实现的第一个 CCM 关键比较，该比较于 2019 年 5 月 20 日生效。目标是确定使用 Kibble 实现千克之间的一致性水平焦耳平衡和 X 射线晶体密度 (XRCD) 方法，并为计算千克的第一个“共识值”提供输入。共识值将作为国际协调传播千克的基础，该传播将持续到实现实验之间达成足够的一致为止。比较由 BIPM 组织，有七名参与者。BIPM、KRISS、NIST 和 NRC 运营的 Kibble 天平，NIM 使用焦耳天平，NMIJ 和 PTB 使用 28Si 球体参与，其质量通过 XRCD 方法确定。这些实现方法用于在真空下校准 1 kg 质量标准。这些标准被（在空气中）送到 BIPM，在那里它们在真空下相互比较，并与 BIPM Pt-Ir 工作标准进行比较。后者经过校准（在空气中）可追溯到国际公斤原型 (IPK)，其质量作为公斤的定义，直到 2019 年 5 月 20 日。 BIPM 的称重结果与测量结果一起传达参与者允许使用参与的实现实验来比较归因于 1 kg 质量标准的值。还可以推导出质量测定与实现实验和 BIPM 作为维护的质量单位之间的一致性水平，可以通过千克的国际原型的质量追溯到普朗克常数。 正文 到达本文的正文，点击最终报告。请注意，此文本出现在 BIPM 关键比较数据库 kcdb.bipm.org/ 的附录 B 中。根据 CIPM 互认安排的规定，最终报告已通过同行评审并由 CCM 批准发布(CIPM MRA)。