Improved frequency measurement of the ${}^1{S}_0$-${}^3{P}_0$ clock transition in ${}^{87}$Sr using the Cs fountain clock at NMIJ as a transfer oscillator

Takehiko Tanabe, Daisuke Akamatsu, Takumi Kobayashi +10

We performed an absolute frequency measurement of the ${}^1{S}_0$-${}^3{P}_0$ transition in ${}^{87}$Sr with a fractional uncertainty of $1.2\times 10^{-15}$, which is less than one thi…