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Q: Quantenoptik
Q 20: Teilchenoptik
Q 20.3: Talk
Tuesday, March 25, 2003, 14:45–15:00, F107
MAGIA - Towards an atom interferometric determination of the Newtonian gravitational constant — •Juergen Stuhler, Marco Fattori, Giacomo Lamporesi, Torsten Petelski, and Guglielmo M. Tino — Dipartimento di Fisica and LENS, Universita’ di Firenze; INFN - Sezione di Firenze, Via Sansone 1, I-50019 Sesto Fiorentino (FI), Italy
We present the basic idea and the status of our experiment MAGIA (Misura Accurata di G mediante Interferometria Atomica), in which we will apply atom interferometic methods to determine the Newtonian gravitational constant G. Free-falling laser-cooled rubidium atoms will be accelerated due to the gravitational potential of nearby source masses. The technique of Raman atom interferometry allows to detect this acceleration and hence to assign a value of G. The use of atoms as probe masses and a double-differential measurement (launch of two atom clouds in a gradiometer configuration and moving the source masses to different positions) will suppress systematic errors. The targeted accuracy of 100 ppm is well below the current uncertainty of 1500 ppm in the accepted value of G=(6.673± 0.010)× 10−11 m3kg−1s−2 (CODATA 1998) and on the order of the discrepancies between the most recent high precision determinations of G.