title: Density fluctuations in a model for vibrated granular media.
abstract: This paper presents the study of density fluctuations in a model for vibrated granular media. Their microscopic origin is shown to be linked to the microscopic disorder in grains packing. Varying vibrations amplitude and duration, several regimes are found for density relaxation. Its power spectrum is well described by power laws.
authors.affiliation: PMMH ESPCI, 10 rue Vauquelin, 75231 Paris Cedex 05, France.
authors.forename: M
authors.initials: M
authors.lastname: Nicodemi
authors.forename: A
authors.initials: A
authors.lastname: Coniglio
authors.forename: H J
authors.initials: HJ
authors.lastname: Herrmann