References of "Jiang, Z"
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See detailAccurate Determination of the Earth Tidal Parameters at the BIPM to Support the Watt Balance Project
Francis, Olivier UL; Rothleitner, Christian UL; Jiang, Z.

in Rizos, C.; Willis, P. (Eds.) Earth on the Edge: Science for a Sustanaible Planet (2014)

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See detailAccurate Gravimetry at the BIPM Watt Balance Site
Jiang, Z.; Palinkas, V.; Francis, Olivier UL et al

in Rizos, C.; Willis, P. (Eds.) Earth on the Edge: Science for a Sustanaible Planet (2014)

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See detailOn the gravimetric contribution to watt balance experiments
Jiang, Z.; Pálinkáš, V.; Francis, Olivier UL et al

in Metrologia (2013), 50(5), 452

It has been recommended that the relative standard uncertainty of the numerical value of the Planck constant required for the redefinition of the kilogram should not exceed 2 × 10 −8 . To reach this goal ... [more ▼]

It has been recommended that the relative standard uncertainty of the numerical value of the Planck constant required for the redefinition of the kilogram should not exceed 2 × 10 −8 . To reach this goal using experiments based on a watt balance, the free-fall acceleration ( g ) traceable to the SI, at a given point and a given time, needs to be known with a sufficiently small uncertainty well below 2 × 10 −8 . Reducing the uncertainty in g allows the other uncertainties related to the watt balance to be increased. Instead of a simultaneous operation of an absolute gravimeter with a watt balance, we propose an alternative approach and demonstrate that a standard uncertainty below 5 µGal (relative uncertainty of 5 × 10 −9 ) is reachable under the conditions at BIPM. Further decreasing the uncertainty could significantly increase commitments in terms of personnel and equipment and would not significantly improve the uncertainty targeted for the BIPM watt balance experiment. A 5 µGal uncertainty might also satisfy the needs of other watt balance experiments underway or planned. In our approach we combine the following information: (1) the Key Comparison Reference Values obtained from the CCM.G-K1, a key comparison carried out in the frame of the International Comparison of Absolute Gravimeters in 2009 (ICAG2009); (2) the accurate gravity network established using the qualified absolute and relative gravimeters; (3) temporal gravity variations based on observed Earth-tide parameters and modelled effects of polar motion and atmospheric mass redistribution; (4) uncertainty estimates that account for non-modelled effects; (5) the option to carry out absolute gravity measurements once every one or two years with two or more gravimeters for monitoring the stability of the gravity field at the BIPM. [less ▲]

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See detailThe 8th International Comparison of Absolute Gravimeters 2009: the first Key Comparison (CCM.G-K1) in the field of absolute gravimetry
Jiang, Z.; Pálinkáš, V.; Arias, F. E. et al

in Metrologia (2012), 49(6), 666

The 8th International Comparison of Absolute Gravimeters (ICAG2009) took place at the headquarters of the International Bureau of Weights and Measures (BIPM) from September to October 2009. It was the ... [more ▼]

The 8th International Comparison of Absolute Gravimeters (ICAG2009) took place at the headquarters of the International Bureau of Weights and Measures (BIPM) from September to October 2009. It was the first ICAG organized as a key comparison in the framework of the CIPM Mutual Recognition Arrangement of the International Committee for Weights and Measures (CIPM MRA) (CIPM 1999). ICAG2009 was composed of a Key Comparison (KC) as defined by the CIPM MRA, organized by the Consultative Committee for Mass and Related Quantities (CCM) and designated as CCM.G-K1. Participating gravimeters and their operators came from national metrology institutes (NMIs) or their designated institutes (DIs) as defined by the CIPM MRA. A Pilot Study (PS) was run in parallel in order to include gravimeters and their operators from other institutes which, while not signatories of the CIPM MRA, nevertheless play important roles in international gravimetry measurements. The aim of the CIPM MRA is to have international acceptance of the measurement capabilities of the participating institutes in various fields of metrology. The results of CCM.G-K1 thus constitute an accurate and consistent gravity reference traceable to the SI (International System of Units), which can be used as the global basis for geodetic, geophysical and metrological observations of gravity. The measurements performed afterwards by the KC participants can be referred to the international metrological reference, i.e. they are SI-traceable. The ICAG2009 was complemented by a number of associated measurements: the Relative Gravity Campaign (RGC2009), high-precision levelling and an accurate gravity survey in support of the BIPM watt balance project. The major measurements took place at the BIPM between July and October 2009. Altogether 24 institutes with 22 absolute gravimeters (one of the 22 AGs was ultimately withdrawn) and nine relative gravimeters participated in the ICAG/RGC campaign. This paper is focused on the absolute gravity campaign. We review the history of the ICAGs and present the organization, data processing and the final results of the ICAG2009. After almost thirty years of hosting eight successive ICAGs, the CIPM decided to transfer the responsibility for piloting the future ICAGs to NMIs, although maintaining a supervisory role through its Consultative Committee for Mass and Related Quantities. [less ▲]

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See detailUpdating the Precise Gravity Network at the BIPM
Jiang, Z.; Arias, E. F.; Tisserand, L. et al

in Geodesy for Planet Earth (2012)

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See detailRelative Gravity Measurement Campaign during the 8th International Comparison of Absolute Gravimeters (2009)
Jiang, Z.; Pálinkáš, V.; Francis, Olivier UL et al

in Metrologia (2012), 49(1), 95

The 8th International Comparison of Absolute Gravimeters (ICAG-2009) and the associated Relative Gravity Campaign (RGC2009) took place at the Bureau International des Poids et Mesures (BIPM) between July ... [more ▼]

The 8th International Comparison of Absolute Gravimeters (ICAG-2009) and the associated Relative Gravity Campaign (RGC2009) took place at the Bureau International des Poids et Mesures (BIPM) between July and October 2009. Altogether 24 institutes with 22 absolute gravimeters and 9 relative gravimeters participated in the ICAG/RGC campaign. Accurate absolute and relative gravity measurements as well as precision levelling measurements were performed on the micro-gravity 3D-grid at the BIPM. The 2009 comparison was the first to be organized as a Comité International des Poids et Mesures (CIPM) metrological Key Comparison under the CIPM MRA (Mutual Recognition Arrangement), which means that the result will be officially recognized by the governmental organizations responsible. As a consequence, the relative gravimeters employed were carefully selected and the measurement schedules were rigorously enforced compared with earlier campaigns. Thus the quality of the RGC2009 and the determination of the BIPM local gravity network were improved. After 30 years and eight successive ICAGs, the BIPM has decided to transfer its role to the national metrological institutes, although the CIPM will continue to organize the key comparison as ICAGs. The background to the RGC2009, and the organization, data processing and final results of the gravity and vertical gravity gradients, are presented in this paper. This report is more detailed than previous final reports of the RGCs. [less ▲]

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See detailFinal report on the Seventh International Comparison of Absolute Gravimeters (ICAG 2005)
Jiang, Z.; Francis, Olivier UL; Vitushkin, L. et al

in Metrologia (2011), 48

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See detailResults of the Seventh International Comparison of Absolute Gravimeters ICAG-2005 at the Bureau International des Poids et Mesures, Sèvres
Vitushkin, L.; Jiang, Z.; Robertsson, L. et al

in Mertikas, Stelios P. (Ed.) Gravity, Geoid and Earth Observation (2010)

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See detailRelative Gravity Measurement Campaign during the 7th International Comparison of Absolute Gravimeters (2005)
Jiang, Z.; Becker, Matthias; Francis, Olivier UL et al

in Metrologia (2009), 46(3), 214

Since the 1st International Comparison of Absolute Gravimeters (ICAG) and accompanying Relative Gravity Campaign (RGC) held at the BIPM in 1981, repeated ICAG-RGCs have been organized every four years. A ... [more ▼]

Since the 1st International Comparison of Absolute Gravimeters (ICAG) and accompanying Relative Gravity Campaign (RGC) held at the BIPM in 1981, repeated ICAG-RGCs have been organized every four years. A total of 19 absolute gravimeters (AG) and 15 relative gravimeters (RG) participated in the 7th ICAG-RGC, which took place in 2005. Co-located absolute and relative gravity measurements as well as precision levelling measurements were carried out. The final version of the absolute g values of the 7th ICAG has been officially released recently. This paper is the final report of the 7th RGC and replaces the preliminary results published earlier. It covers the organization of the RGC and the data processing, analyses RG behaviour, computes g , δ g and O AG (offset of AG) and discusses their uncertainties. In preparation for the BIPM key comparison ICAG-2009, a standard data-processing procedure has been developed and installed in the BIPM ICAG-RGC software package, GraviSoft. This was used for the final data processing. [less ▲]

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See detailResults of the Sixth International Comparison of Absolute Gravimeters, ICAG-2001
Vitushkin, L.; Becker, M.; Jiang, Z. et al

in Metrologia (2002), 39(5), 407-427

The Sixth International Comparison of Absolute Gravimeters was held from 5 June to 28 August 2001 at the Bureau International des Poids et Mesures (BIPM), Sevres. Seventeen absolute gravimeters were used ... [more ▼]

The Sixth International Comparison of Absolute Gravimeters was held from 5 June to 28 August 2001 at the Bureau International des Poids et Mesures (BIPM), Sevres. Seventeen absolute gravimeters were used to make measurements at five sites of the BIPM gravity network. The vertical gravity gradients at the sites and the ties between them were also measured using seventeen relative gravimeters. For the first time the ties were also measured using absolute gravimeters. Various methods of processing the absolute and relative data were tested to calculate the results. The final results of ICAG-2001 are presented. The acceleration due to gravity at a height of 0.90 m is given as (980925701.2 ± 5.5) Gal and (980928018.8 ± 5.5) Gal for sites A and B, respectively, calculated using a combined adjustment of the absolute and relative data. [less ▲]

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