Evaluation of caesium atomic fountain NICT-CsF1

In this paper, we describe the first caesium atomic fountain primary frequency standard NICT-CsF1 of National Institute of Information Communications Technology ( NICT) in Tokyo, Japan. The structure of the NICT-CsF1 system and evaluation procedure of the systematic frequency shifts and their uncertainties are presented. Typically, NICT-CsF1 has a frequency stability of 4 x 10(-13)/tau(1/2) and a frequency uncertainty of 1.9 x 10(-15).