Evaluation of the accuracy of the optically pumped caesium beam primary frequency standard of BNM-LPTF

The primary frequency standard LPTF-JPO employs a caesium thermal beam, and optical pumping techniques. We present the main parts of the design. The short-term stability is reported, σy(τ) = 3.5 × 10−13 τ−1/2, where τ is the averaging time. The general expression for frequency shift for a square-wave frequency modulation is given. We discuss the determination of each frequency shift, and we present new methods to evaluate some of them. A relative combined standard uncertainty of 6.4 × 10−15 (1 σ) is obtained.

[1]  J. Vanier,et al.  The quantum physics of atomic frequency standards , 1989 .

[2]  Ken Hagimoto,et al.  Accuracy evaluation of the optically pumped Cs frequency standard at NRLM , 1999, IEEE Trans. Instrum. Meas..

[3]  Feasibility of end to end phase shift correction from the outside of sealed cesium beam tubes , 1991 .

[4]  G. D. Rovera,et al.  Rabi pedestal shifts as a diagnostic tool for primary frequency standards , 1994 .

[5]  Alfred Kastler,et al.  Quelques suggestions concernant la production optique et la détection optique d'une inégalité de population des niveaux de quantifigation spatiale des atomes. Application à l'expérience de Stern et Gerlach et à la résonance magnétique , 1950 .

[6]  A. Premoli,et al.  Effects of Servo Loop Modulation in Atomic Beam Frequency Standards Employing a Ramsey Cavity , 1987, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[7]  Emeric de Clercq,et al.  Estimation of the end-to-end phase shift without beam reversal in Cs beam frequency standards , 1999, IEEE Trans. Instrum. Meas..

[8]  A. Makdissi,et al.  Phase and light shift determination in an optically pumped cesium beam frequency standard , 2000, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[9]  I. I. Rabi,et al.  The Molecular Beam Resonance Method for Measuring Nuclear Magnetic Moments The Magnetic Moments of 3 Li 6 , 3 Li 7 and 9 F 19 , 1939 .

[10]  Wayne M. Itano,et al.  Shift of 2 S 12 hyperfine splittings due to blackbody radiation , 1982 .

[11]  Kurt Gibble,et al.  Laser-cooled 87Rb clock , 1999, IEEE Trans. Instrum. Meas..

[12]  Giordano,et al.  State selection in a cesium beam by laser-diode optical pumping. , 1987, Physical review. A, General physics.

[13]  Takeshi Ikegami,et al.  Light shifts in an optically pumped Cs beam frequency standard , 1991 .

[14]  V. Giordano,et al.  Analysis of the noise sources in an optically pumped cesium beam resonator , 1993 .

[15]  A. Makdissi,et al.  A regularization approach for the determination of the time of flight distribution in the cesium beam standards , 1997, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[16]  J. Shirley,et al.  Velocity distributions calculated from the Fourier transforms of Ramsey lineshapes , 1997 .

[17]  Andreas Bauch,et al.  The PTB primary clock CS3: type B evaluation of its standard uncertainty , 1996 .

[18]  André Clairon,et al.  Measurement of the Stark shift of the Cs hyperfine splitting in an atomic fountain , 1998 .

[19]  G. Theobald,et al.  Frequency shifts in cesium beam clocks induced by microwave leakages , 1998, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[20]  A signal approach analysis of the Ramsey pattern in a cesium beam frequency standard , 1996 .

[21]  Norman F. Ramsey,et al.  A Molecular Beam Resonance Method with Separated Oscillating Fields , 1950 .

[22]  Jon H. Shirley,et al.  A new cavity configuration for cesium beam primary frequency standards , 1988 .

[23]  A. Premoli,et al.  Pulling by Neighbouring Transitions and its Effects on the Performance of Caesium-Beam Frequency Standards , 1984 .

[24]  Y. Koga.  An Improved Method of Measuring the Zeeman Shift in Cesium Beam Frequency Standards , 1984 .

[25]  V. Giordano,et al.  Ground state Zeeman coherence effects in an optically pumped cesium beam , 1989 .

[27]  Andreas Bauch,et al.  Performance of the PTB reconstructed primary clock CS1 and an estimate of its current uncertainty , 1998 .

[28]  Jon H. Shirley,et al.  The accuracy evaluation of NIST-7 , 1995 .

[29]  André Clairon,et al.  The LPTF optically pumped primary frequency standard , 1993 .

[30]  Andreas Bauch,et al.  CS2: The PTB's new primary clock , 1987, IEEE Transactions on Instrumentation and Measurement.

[31]  André Clairon,et al.  An analysis of major frequency shifts in the LPTF optically pumped primary frequency standard , 1994 .

[32]  Robin P. Giffard,et al.  Frequency pulling by hyperfine σ transitions in cesium beam atomic frequency standards , 1991 .

[33]  Andreas Bauch,et al.  Experimental Verification of the Shift of the Cesium Hyperfine Transition Frequency due to Blackbody Radiation , 1997 .

[34]  A. G. Mungall,et al.  The New NRC 2.1 Metre Primary Cesium Beam Frequency Standard, Cs V , 1973 .