title: Complex-plasma boundaries.
abstract: This study deals with the boundary between a normal plasma of ions and electrons, and an adjacent complex plasma of ions, electrons, and microparticles, as found in innumerable examples in nature. Here we show that the matching between the two plasmas involve electrostatic double layers. These double layers explain the sharp boundaries observed in the laboratory and in astrophysics. A modified theory is derived for the double layers that form at the discontinuity between two different complex plasmas and at the point of contact of three complex plasmas. The theory is applied to the first measurements from the Plasma Kristall Experiment (PKE) Nefedov Laboratory in the International Space Station.
authors.affiliation: Centre for Interdisciplinary Plasma Science, Max-Planck Institut für Extraterrestrische Physik, D-85740 Garching, Germany.
authors.forename: B M
authors.initials: BM
authors.lastname: Annaratone
authors.forename: S A
authors.initials: SA
authors.lastname: Khrapak
authors.forename: P
authors.initials: P
authors.lastname: Bryant
authors.forename: G E
authors.initials: GE
authors.lastname: Morfill
authors.forename: H
authors.initials: H
authors.lastname: Rothermel
authors.forename: H M
authors.initials: HM
authors.lastname: Thomas
authors.forename: M
authors.initials: M
authors.lastname: Zuzic
authors.forename: V E
authors.initials: VE
authors.lastname: Fortov
authors.forename: V I
authors.initials: VI
authors.lastname: Molotkov
authors.forename: A P
authors.initials: AP
authors.lastname: Nefedov
authors.forename: S
authors.initials: S
authors.lastname: Krikalev
authors.forename: Yu P
authors.initials: YP
authors.lastname: Semenov