Superconducting Gravimeter Calibration by CoLocated Gravity Observations: Results from GWR C025

Table 2

Weighted average 𝑎₀ of the calibration factor obtained by the calibration experiments in Vienna between 1996 and 2007 and at Conrad observatory between 2008 and 2012. Equation (4) was applied for calculations.

Vienna
Method	Single drop
Outlier detection	3𝜎-criterion			modified Z-score method			M
	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)
FG5 + JILAg; with AG drift adjustment	−779.5978	0.5272; 0.68	2.3008; 2.95	−779.6254	0.5278; 0.68	2.4234; 3.11	6
FG5 + JILAg; no AG drift adjustment	−779.6828	0.5272; 0.68	2.8414; 3.64	−779.7127	0.5278; 0.68	2.8677; 3.68	6
Vienna
Method	Set mean			Running average
Outlier detection	modified Z-score method			modified Z-score method			M
	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)
FG5 + JILAg; with AG drift adjustment	−779.7295	7.0139; 9.00	2.3820; 3.05	−779.5454	0.5297; 0.68	2.7151; 3.48	6
Conrad observatory
Method	Single drop
Outlier detection	3𝜎-criterion			modified Z-score method			M
	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)
CG5	− 779.1628	0.2295; 0.29	0.5392; 0.69				10
FG5 + JILAg; with AG drift adjustment	−779.4676	0.1774; 0.23	0.5268; 0.68	−779.4566	0.1746; 0.22	0.3721; 0.48	7
FG5 + JILAg; no AG drift adjustment	−779.6434	0.1774; 0.23	1.0058; 1.29	−779.6230	0.1746; 0.22	0.9890; 1.27	7
Conrad observatory
Method	Set mean			Running average
Outlier detection	modified Z-score method			modified Z-score method			M
	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)	𝑎0 (nms^−2/V)	𝑒 (nms^−2/V) (‰)	𝑟 (nms^−2/V) (‰)
FG5 + JILAg; with AG drift adjustment	−779.4982	1.9087; 2.45	0.3584; 0.46	−779.4620	0.1756; 0.23	0.3875; 0.50	7