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SIM Time Scale: 10 years of operation



J. M. Lopez, Michael A. Lombardi, E. de Carlos, N. Munoz, C. Ortiz


The Inter-American Metrology System (SIM) is one of the world's five major Regional Metrology Organizations (RMO's). Starting in 2005, the SIM Time and Frequency Metrology Working Group (SIM TFWG) developed a time and frequency comparison network for the Americas (SIMTN). Currently 23 national metrology institutes from the SIM region participate in the SIMTN. Since 2008 the SIM TFWG is producing a time scale called SIM Time Scale (SIMT). SIMT is an averaged time scale computed in near real-time (every hour) from time difference data that the SIMTN produces and publishes every 10 minutes. In this paper, a SIMT evaluation based on data from August 2016 to January 2018 is presented.
Conference Dates
July 8-13, 2018
Conference Location
Paris, FR
Conference Title
IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM)


atomic clocks, international comparisons, time scales


Lopez, J. , Lombardi, M. , de Carlos, E. , Munoz, N. and Ortiz, C. (2018), SIM Time Scale: 10 years of operation, IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM), Paris, FR, [online], (Accessed April 24, 2024)
Created March 28, 2018, Updated October 12, 2021