SRATR

SRATR, an acronym for Standard Reference Atomic Time, is a fundamental time scale maintained by the International Bureau of Weights and Measures (BIPM). It is established by averaging the timekeeping characteristics of a large ensemble of cesium atomic clocks located at national metrology institutes around the world. The goal of SRATR is to provide a highly stable and accurate representation of time, free from the irregularities inherent in any single clock.

The definition of SRATR involves complex algorithms that account for the performance and drifts of the participating clocks. This process ensures that SRATR is more stable than any individual atomic clock and is considered the closest practical approximation to an ideal atomic time scale. SRATR serves as the basis for other international time scales, including International Atomic Time (TAI).

SRATR is not directly accessible but is realized through the dissemination of TAI. TAI, in turn, is the basis for Coordinated Universal Time (UTC), the civil time standard used worldwide. Therefore, SRATR plays a crucial, albeit indirect, role in the global infrastructure of timekeeping and navigation. Its accuracy and stability are essential for scientific research, technological applications, and international synchronization.