A Comparison of Cs Fountain Primary Frequency Standards

fountain primary frequency standard to report to the BIPM in September 1995 with a fountain uncertainty of 3x10-15. There was also about an equivalent amount of

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PROGRESS ON A PORTABLE RUBIDIUM FOUNTAIN FREQUENCY

FOUNTAIN FREQUENCY STANDARD * P. D. Kunz ([email protected]), T. P. Heavner ([email protected]), and S. R. Jefferts ([email protected]) Time and Frequency

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A cesium fountain frequency standard: preliminary results ...

Laser cooling of atoms has opened up new possibilities in the field of atomic frequency standards. A cesium atomic fountain, first proposed by Zacharias in 1953, is

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Realisation of a Frequency Standard Using an Atomic Fountain

We report the realisation and preliminary study of a frequency standard using a fountain of laser cooled caesium atoms. Our apparatus uses a magneto-optical trap

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NPL Cs fountain frequency standards and the quest for the ...

Operation of atomic fountain frequency standards has been one of the first and most successful examples of applications of the laser cooling technology. A prototype

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Time and Frequency Technology Related to the Operation of a

Cesium Fountain Primary Frequency Standard* Thomas E. Parker National Institute of Standards and Technology Time and Frequency Division 325 Broadway Boulder, CO

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Development of a caesium fountain primary frequency ...

Whibberley, P B; Henderson, D; Lea, S N (1999) Development of a caesium fountain primary frequency standard at the NPL. In: Proc. 1999 Joint Meeting of the

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A Comparison of Cs Fountain Primary Frequency Standards

fountain primary frequency standard to report to the BIPM in September 1995 with a fountain uncertainty of 3x10-15. There was also about an equivalent amount of frequency transfer uncertainty. Twelve reports were submitted by the Laboratoire Primaire du Temps et des Frequences (now Bureau National de Métrologie Systèmes de Référence Temps Espace (BNM-SYRTE)) in France from

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[PDF] NPL Cs fountain frequency standards and the quest ...

NPL operates a system of two primary caesium fountain clocks consisting of a fully characterised standard NPL-CsF2 together with a new standard NPL-CsF3, which has recently become operational. Both fountains feature a single-stage vapour-loaded magneto-optical trap as the source of cold atoms and an approximate cancellation of the potentially large cold collision frequency shift. As a result ...

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An Alternative Cold Cesium Frequency Standard:The ...

An Alternative Cold Cesium Frequency Standard: The Continuous Fountain Gregor Dudle, Gaetano Mileti, Alain Joyet, Emmanuel Fretel, Patrick Berthoud, and Pierre Thomann, Member, IEEE Abstract—We report on the primary frequency standard now under construction at the Observatoire de Neuchˆatel (ON). The design is based on a continuous fountain of laser- cooled cesium atoms, which

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Development of Cs atomic fountain frequency standard at ...

Communications research laboratory (CRL) has been developing a Cesium atomic fountain primary frequency standard. Cs atoms are cooled to below 2 /spl mu/K by both magneto-optical trap (MOT) and polarization gradient cooling (PGC), and launched vertically by moving molasses method. The launched atoms pass through a microwave cavity twice, on the way upward and downward, and give rise to

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Development of cesium fountain frequency standard at the ...

the country’s first cesium fountain frequency standard a few years ago. The aim of this entire activity is to build a primary frequency standard for India with a relative un-certainty better than 1 × 10–15. The NPLI fountain has a (0, 0, 1) geometry of the magneto-optical trap (MOT) for cooling and launching operations. In this geometry, four out of the six cooling beams are in the ...

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Evaluation of PTB primary caesium fountain frequency ...

Evaluation of PTB primary caesium fountain frequency standard CSF2 between MJD 59304 - MJD 59334 PTB's primary caesium fountain frequency standard CSF2 was operated between MJD 59304, 0:00 UTC and MJD 59334, 0:00 UTC. Frequency comparisons were made with respect to PTB hydrogen maser H9, BIPM code 1400509. The relative frequency instability of the relative frequency

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Evaluation of PTB primary caesium fountain frequency ...

PTB's primary caesium fountain frequency standard CSF2 was operated between MJD 57839, 0:00 UTC and MJD 57869, 0:00 UTC. Frequency comparisons were made with respect to PTB hydrogen maser H10, BIPM code 1400510. The actual measurement time amounts to 87.7% of the 30 24 hours. Assuming that white frequency noise is the dominant noise source, a statistical uncertainty uA = 0.10

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Power Dependence of the Frequency Bias Caused by Spurious ...

in an atomic fountain frequency standard. We discuss how such shifts behave as a function of power variations of the excitation carrier and in the spur-to-carrier ratio. The dis-cussion here is limited to the case of single-sideband spurs, which are generally much more troublesome due to their ability to cause frequency shifts. We find an extremely rich and unintuitive behavior of these ...

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Peter Whibberley - NPL

After moving into time and frequency metrology, Peter worked on an experimental optically-pumped caesium beam frequency standard, and then on the construction and evaluation of a prototype caesium fountain primary frequency standard, initially in collaboration with the University of Oxford. He next took over responsibility for the operation and development of NPL's time scale systems and time ...

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An Alternative Cold Cesium Frequency Standard:The ...

An Alternative Cold Cesium Frequency Standard: The Continuous Fountain Gregor Dudle, Gaetano Mileti, Alain Joyet, Emmanuel Fretel, Patrick Berthoud, and Pierre Thomann, Member, IEEE Abstract—We report on the primary frequency standard now under construction at the Observatoire de Neuchˆatel (ON). The design is based on a continuous fountain of laser- cooled cesium atoms, which

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Accuracy evaluations of the Cs fountain primary frequency ...

Abstract: The caesium fountain primary frequency standard NIM5 has been developed at the National Institute of Metrology (NIM) of China. The NIM5 loads atoms in an optical molasses (OM) from the background Cs vapor directly. Atoms are then cooled to a temperature of about 2 μK and launched to a height of 81 cm. The fringes of the Ramsey pattern have a width of about 1 Hz. Stabilizing the 9.19 ...

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Operation of the NIST-F1 Cesium Fountain Primary Frequency ...

13/09/2005  The operation of a caesium fountain primary frequency standard is greatly influenced by the characteristics of two other important capabilities. The first is a stable frequency reference and the second is the frequency-transfer system. A stable frequency reference such as a hydrogen maser is a virtual necessity since essentially no fountain dead time can be tolerated without it. The frequency ...

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Time and Frequency Technology Related to the Operation of a

Cesium Fountain Primary Frequency Standard* Thomas E. Parker National Institute of Standards and Technology Time and Frequency Division 325 Broadway Boulder, CO 80305 USA Abstract The operation of a cesium fountain primary frequency standard is greatly facilitated by the presence of two other important capabilities. The first is a stable frequency reference and the second is one or more

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NIST Cesium Fountains – Current Status and Future ...

12/09/2007  NIST-F1 is a laser-cooled cesium fountain based frequency standard with an inaccuracy of less than δ f/f {less than or equal to} 5×10-16 limited mainly by the radiation field in the room-temperature fountain (blackbody shift). NIST-F1 is one of the best cesium fountain currently contributing to international atomic time, but has reached a point that it is impractical to improve its accuracy ...

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Cancellation of the collisional frequency shift in caesium ...

Cancellation of the collisional frequency shift in caesium fountain clocks. Krzysztof Szymaniec. National Physical Laboratory. Time Frequency Users Club. 22 May 2008. Outline: ¾Who needs a fountain standard? ¾How does it work? ¾Accuracy limits −collisions ¾Operation at zero-collisional shift point. Model of a clock. Each clock consist of two parts: - an oscillator, which provides a ...

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Cs fountain primary standard - Atomic Frequency Standards ...

Cs fountain primary standard. INR i M is one of the seven metrology laboratories that contribute to the calibration of the International Atomic Time (TAI) with primary frequency standards. The first Italian Cs fountain, ITCsF1, has been operating since 2003 with an accuracy of 5E-16. Since 2012 a cryogenic Cs fountain clock is under operation ...

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Evaluation of PTB primary caesium fountain frequency ...

PTB's primary caesium fountain frequency standard CSF2 was operated between MJD 57839, 0:00 UTC and MJD 57869, 0:00 UTC. Frequency comparisons were made with respect to PTB hydrogen maser H10, BIPM code 1400510. The actual measurement time amounts to 87.7% of the 30 24 hours. Assuming that white frequency noise is the dominant noise source, a statistical uncertainty uA = 0.10

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Design Details of FOCS-2, an Improved Continuous Cesium ...

FOCS-2, an Improved Continuous Cesium Fountain Frequency Standard. TimeNav’07- EFTF.IEEE-FCS’07, May 2007, Genève, Switzerland. 6 p. ￿hal-00165376￿ Design Details of FOCS-2, an Improved Continuous Cesium Fountain Frequency Standard Ferenc Fuzesi¨ ¶, Mark D. Plimmer‡, Gregor Dudle∗, Jocelyne Gu´ena § and Pierre Thomann† ∗Federal Office of Metrology METAS, Lindenweg

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Frequency Conversion Cntrol Scheme For Music Fountain ...

18/12/2019  Weak, using a signal transmitter can output a standard DC voltage signal of 0-5V, and then input this signal to the analog input port of each inverter through a multi-channel distribution controller, as the frequency input signal of the inverter, That can achieve the control requirements of the musical fountain. All inverters use the PI9000 series of general-purpose vector products. Among them ...

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