Final report of the regional key comparison EURAMET.M.G-K1: European Comparison of Absolute Gravimeters ECAG-2011

International audienceDuring November 2011 a EURAMET key comparison of absolute gravimeters was organized in the Underground Laboratory for Geodynamics in Walferdange, Luxemburg. The comparison assembled 22 participants coming from 16 countries and four different continents. The comparison was divided into two parts: a key comparison that included six National Metrology Institutes or Designated Institutes, and a pilot study including all participants. The global result given by the pilot study confirms that all instruments are absolutely coherent with each other. The results obtained in the key comparison confirm a good agreement between the NMI instruments. Finally, a link to ICAG-2009 shows also that the NMI gravimeters are stable in time

Final report of the regional key comparison EURAMET.M.G-K1: European Comparison of Absolute Gravimeters ECAG-2011

International audienceDuring November 2011 a EURAMET key comparison of absolute gravimeters was organized in the Underground Laboratory for Geodynamics in Walferdange, Luxemburg. The comparison assembled 22 participants coming from 16 countries and four different continents. The comparison was divided into two parts: a key comparison that included six National Metrology Institutes or Designated Institutes, and a pilot study including all participants. The global result given by the pilot study confirms that all instruments are absolutely coherent with each other. The results obtained in the key comparison confirm a good agreement between the NMI instruments. Finally, a link to ICAG-2009 shows also that the NMI gravimeters are stable in time

The European Comparison of Absolute Gravimeters 2011 (ECAG-2011) in Walferdange, Luxembourg: results and recommendations

We present the results of the third European Comparison of Absolute Gravimeters held in Walferdange, Grand Duchy of Luxembourg, in November 2011. Twenty-two gravimeters from both metrological and non-metrological institutes are compared. For the first time, corrections for the laser beam diffraction and the self-attraction of the gravimeters are implemented. The gravity observations are also corrected for geophysical gravity changes that occurred during the comparison using the observations of a superconducting gravimeter. We show that these corrections improve the degree of equivalence between the gravimeters. We present the results for two different combinations of data. In the first one, we use only the observations from the metrological institutes. In the second solution, we include all the data from both metrological and non-metrological institutes. Those solutions are then compared with the official result of the comparison published previously and based on the observations of the metrological institutes and the gravity differences at the different sites as measured by non-metrological institutes. Overall, the absolute gravity meters agree with one another with a standard deviation of3.1 µ Gal. Finally, the results of this comparison are linked to previous ones. We conclude with some important recommendations for future comparisons

CCM.G-K2 key comparison

International audienceIn November 2013 an International Key Comparison, CCM.G-K2, was organized in the Underground Laboratory for Geodynamics in Walferdange. The comparison has assembled 25 participants coming from 19 countries and four different continents. The comparison was divided into two parts: the key comparison that included 10 NMIs or DIs, and the pilot study including all participants. The global result given by the pilot study confirms that all instruments are absolutely coherent to each other. The results obtained for the key comparison confirm a good agreement between the NMI instruments

CCM.G-K2 key comparison

In November 2013 an International Key Comparison, CCM.G-K2, was organized in the Underground Laboratory for Geodynamics in Walferdange. The comparison has assembled 25 participants coming from 19 countries and four different continents. The comparison was divided into two parts: the key comparison that included 10 NMIs or DIs, and the pilot study including all participants. The global result given by the pilot study confirms that all instruments are absolutely coherent to each other. The results obtained for the key comparison confirm a good agreement between the NMI instruments. Main text. To reach the main text of this paper, click on Final Report [http://www.bipm.org/utils/common/pdf/final_reports/M/G-K2/CCM.G-K2.pdf] . Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/ [http://kcdb.bipm.org/] . The final report has been peer-reviewed and approved for publication by CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA)

CCM.G-K2 key comparison

International audienceIn November 2013 an International Key Comparison, CCM.G-K2, was organized in the Underground Laboratory for Geodynamics in Walferdange. The comparison has assembled 25 participants coming from 19 countries and four different continents. The comparison was divided into two parts: the key comparison that included 10 NMIs or DIs, and the pilot study including all participants. The global result given by the pilot study confirms that all instruments are absolutely coherent to each other. The results obtained for the key comparison confirm a good agreement between the NMI instruments