We present two novel methods, tested by LISA Pathfinder, to measure the gravitational constant G for the first time in space. Experiment 1 uses electrostatic suspension forces to measure a change in acceleration of a test mass due to a displaced source mass. Experiment 2 measures a change in relative acceleration between two test masses due to a slowly varying fuel tank mass. Experiment 1 gave a value of G=6.71±0.42(×10−11) m3 s−2 kg−1 and experiment 2 gave 6.15±0.35(×10−11) m3 s−2 kg−1, both consistent with each other to 1σ and with the CODATA 2014 recommended value of 6.67408±0.00031(×10−11) m3 s−2 kg−1 to 2σ. We outline several ideas to improve the results for a future experiment, and we suggest that a measurement in space would isolate many terrestrial issues that could be responsible for the inconsistencies between recent measurements.
Novel methods to measure the gravitational constant in space
Grimani C.Membro del Collaboration Group
;
2019
Abstract
We present two novel methods, tested by LISA Pathfinder, to measure the gravitational constant G for the first time in space. Experiment 1 uses electrostatic suspension forces to measure a change in acceleration of a test mass due to a displaced source mass. Experiment 2 measures a change in relative acceleration between two test masses due to a slowly varying fuel tank mass. Experiment 1 gave a value of G=6.71±0.42(×10−11) m3 s−2 kg−1 and experiment 2 gave 6.15±0.35(×10−11) m3 s−2 kg−1, both consistent with each other to 1σ and with the CODATA 2014 recommended value of 6.67408±0.00031(×10−11) m3 s−2 kg−1 to 2σ. We outline several ideas to improve the results for a future experiment, and we suggest that a measurement in space would isolate many terrestrial issues that could be responsible for the inconsistencies between recent measurements.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
