title: Rotation of a two-dimensional Coulomb cluster in a magnetic field.
abstract: A coordinated study of a laboratory experiment, a computer simulation, and a theoretical analysis reveals a structure and its dynamic motion of a Coulomb cluster trapped in a plasma with a confining potential in the presence of gravitational and magnetic fields. Charged dust particulates are found to form a circle in a horizontal plane with a radius determined by a balance of a restoring force due to a confining potential and the screened Coulomb force between dust particulates. The dust particulates in a circle show angular rotation with the structure intact, while they oscillate radially around the equilibrium orbit. The analytical study reveals the oscillatory rotational nature of dust particulates as a result of coupling between the Lorentz force and the harmonic oscillation.
authors.affiliation: Faculty of Engineering, Yokohama National University, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Ishihara
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Kamimura
authors.forename: Keiichi I
authors.initials: KI
authors.lastname: Hirose
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Sato