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تسجيل مستخدم جديدIntermittent optical frequency measurements to reduce the dead time uncertainty of frequency link
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The absolute frequency of the $^{87}{rm Sr}$ lattice clock transition was evaluated with an uncertainty of $1.1times 10^{-15}$ using a frequency link to the international atomic time (TAI). The frequency uncertainty of a hydrogen maser used as a transfer oscillator was reduced by homogeneously distributed intermittent measurement over a five-day grid of TAI. Three sets of four or five days measurements as well as systematic uncertainty of the clock at $8.6times 10^{-17}$ have resulted in an absolute frequency of $^{87}{rm Sr} {}^1S_0 - {}^3P_0$ clock transition to be 429 228 004 229 872.85 (47) Hz.
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