title: Tests of Lorentz invariance using a microwave resonator.
abstract: The frequencies of a cryogenic sapphire oscillator and a hydrogen maser are compared to set new constraints on a possible violation of Lorentz invariance. We determine the variation of the oscillator frequency as a function of its orientation (Michelson-Morley test) and of its velocity (Kennedy-Thorndike test) with respect to a preferred frame candidate. We constrain the corresponding parameters of the Mansouri and Sexl test theory to delta-beta + 1/2 = (1.5+/-4.2) x 10(-9) and beta-alpha - 1= (-3.1+/-6.9) x 10(-7) which is of the same order as the best previous result for the former and represents a 30-fold improvement for the latter.
authors.affiliation: Bureau International des Poids et Mesures, Pavillon de Breteuil, 92312 Sèvres CEDEX, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Wolf
authors.forename: Sébastien
authors.initials: S
authors.lastname: Bize
authors.forename: André
authors.initials: A
authors.lastname: Clairon
authors.forename: André N
authors.initials: AN
authors.lastname: Luiten
authors.forename: Giorgio
authors.initials: G
authors.lastname: Santarelli
authors.forename: Michael E
authors.initials: ME
authors.lastname: Tobar