  Dependencies of levitation position of positively charged fine-particles on
plasma parameters are investigated. The charges on the particles become
positive in a cross-field sheath between magnetized double plasmas with
different potentials separated vertically by horizontal magnetic field, because
ion current flowing from a lower high-potential plasma surpasses electron
current coming across the magnetic field from an upper low-potential plasma.
  From measurement of the resonance frequency of the particles driven by
external oscillating electric field, the charge on particle is estimated to be
of the order of 10e2. Variation of particle levitation positions can be
explained by the change of the charges.
