title: Measurement of the gravity-field curvature by atom interferometry.
abstract: We present the first direct measurement of the gravity-field curvature based on three conjugated atom interferometers. Three atomic clouds launched in the vertical direction are simultaneously interrogated by the same atom interferometry sequence and used to probe the gravity field at three equally spaced positions. The vertical component of the gravity-field curvature generated by nearby source masses is measured from the difference between adjacent gravity gradient values. Curvature measurements are of interest in geodesy studies and for the validation of gravitational models of the surrounding environment. The possibility of using such a scheme for a new determination of the Newtonian constant of gravity is also discussed.
authors.affiliation: Dipartimento di Fisica e Astronomia and LENS, Università di Firenze, INFN Sezione di Firenze, via Sansone 1, I-50019 Sesto Fiorentino, Firenze, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Rosi
authors.affiliation: European Space Agency, Keplerlaan 1, 2200 AG Noordwijk, Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: Cacciapuoti
authors.affiliation: Dipartimento di Fisica e Astronomia and LENS, Università di Firenze, INFN Sezione di Firenze, via Sansone 1, I-50019 Sesto Fiorentino, Firenze, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Sorrentino
authors.affiliation: Dipartimento di Fisica e Astronomia and LENS, Università di Firenze, INFN Sezione di Firenze, via Sansone 1, I-50019 Sesto Fiorentino, Firenze, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Menchetti
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Bologna, Via Berti-Pichat 6/2, I-40126 Bologna, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Prevedelli
authors.affiliation: Dipartimento di Fisica e Astronomia and LENS, Università di Firenze, INFN Sezione di Firenze, via Sansone 1, I-50019 Sesto Fiorentino, Firenze, Italy.
authors.forename: G M
authors.initials: GM
authors.lastname: Tino