title: Cyclotron instability in the afterglow mode of minimum-B ECRIS.
abstract: It was shown recently that cyclotron instability in non-equilibrium plasma of a minimum-B electron cyclotron resonance ion source (ECRIS) causes perturbation of the extracted ion current and generation of strong bursts of bremsstrahlung emission, which limit the performance of the ion source. The present work is devoted to the dynamic regimes of plasma instability in ECRIS operated in pulsed mode. Instability develops in decaying plasma shortly after heating microwaves are switched off and manifests itself in the form of powerful pulses of electromagnetic emission associated with precipitation of high energy electrons. Time-resolved measurements of microwave emission bursts are presented. It was found that even in various gases (helium and oxygen were studied) and at different values of magnetic field and heating power, the dynamic spectra demonstrate common features: decreasing frequency within a single burst as well as from one burst to another.
authors.affiliation: Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), 46 Ul'yanova St., 603950 Nizhny Novgorod, Russia.
authors.forename: I
authors.initials: I
authors.lastname: Izotov
authors.affiliation: Department of Physics, University of Jyvaskyla, P.O. Box 35 (YFL), 40500 Jyvaskyla, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Kalvas
authors.affiliation: Department of Physics, University of Jyvaskyla, P.O. Box 35 (YFL), 40500 Jyvaskyla, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Koivisto
authors.affiliation: Department of Physics, University of Jyvaskyla, P.O. Box 35 (YFL), 40500 Jyvaskyla, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Komppula
authors.affiliation: Department of Physics, University of Jyvaskyla, P.O. Box 35 (YFL), 40500 Jyvaskyla, Finland.
authors.forename: R
authors.initials: R
authors.lastname: Kronholm
authors.affiliation: Department of Physics, University of Jyvaskyla, P.O. Box 35 (YFL), 40500 Jyvaskyla, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Laulainen
authors.affiliation: Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), 46 Ul'yanova St., 603950 Nizhny Novgorod, Russia.
authors.forename: D
authors.initials: D
authors.lastname: Mansfeld
authors.affiliation: Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), 46 Ul'yanova St., 603950 Nizhny Novgorod, Russia.
authors.forename: V
authors.initials: V
authors.lastname: Skalyga
authors.affiliation: Department of Physics, University of Jyvaskyla, P.O. Box 35 (YFL), 40500 Jyvaskyla, Finland.
authors.forename: O
authors.initials: O
authors.lastname: Tarvainen