Improved Frequency Measurement of the S-1(0)-P-3(0) Clock Transition in Sr-87 Using a Cs Fountain Clock as a Transfer Oscillator

摘要

We performed an absolute frequency measurement of the S-1(0)-P-3(0) transition in Sr-87 with a fractional uncertainty of 1.2 x 10(-15), which is less than one-third that of our previous measurement. A caesium fountain atomic clock was used as a transfer oscillator to reduce the uncertainty of the link between a strontium optical lattice clock and the SI second. The absolute value of the transition frequency is 429 228 004 229 873.56(49) Hz.