title: Experimental observation of optical rotation generated in vacuum by a magnetic field.
abstract: We report the experimental observation of a light polarization rotation in vacuum in the presence of a transverse magnetic field. Assuming that data distribution is Gaussian, the average measured rotation is (3.9 +/- 0.5) x 10(-12) rad/pass, at 5 T with 44 000 passes through a 1 m long magnet, with lambda = 1064 nm. The relevance of this result in terms of the existence of a light, neutral, spin-zero particle is discussed.
authors.affiliation: Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Trieste and Università di Trieste, Trieste, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Zavattini
authors.forename: G
authors.initials: G
authors.lastname: Zavattini
authors.forename: G
authors.initials: G
authors.lastname: Ruoso
authors.forename: E
authors.initials: E
authors.lastname: Polacco
authors.forename: E
authors.initials: E
authors.lastname: Milotti
authors.forename: M
authors.initials: M
authors.lastname: Karuza
authors.forename: U
authors.initials: U
authors.lastname: Gastaldi
authors.forename: G
authors.initials: G
authors.lastname: Di Domenico
authors.forename: F
authors.initials: F
authors.lastname: Della Valle
authors.forename: R
authors.initials: R
authors.lastname: Cimino
authors.forename: S
authors.initials: S
authors.lastname: Carusotto
authors.forename: G
authors.initials: G
authors.lastname: Cantatore
authors.forename: M
authors.initials: M
authors.lastname: Bregant