title: Threefold Increase of the Bulk Electron Temperature of Plasma Discharges in a Magnetic Mirror Device.
abstract: This Letter describes plasma discharges with a high temperature of bulk electrons in the axially symmetric high-mirror-ratio (R=35) open magnetic system gas dynamic trap (GDT) in the Budker Institute (Novosibirsk). According to Thomson scattering measurements, the on-axis electron temperature averaged over a number of sequential shots is 660±50  eV with the plasma density being 0.7×10^{19}  m^{-3}; in few shots, electron temperature exceeds 900 eV. This corresponds to at least a threefold increase with respect to previous experiments both at GDT and at other comparable machines, thus, demonstrating the highest quasistationary (about 1 ms) electron temperature achieved in open traps. The breakthrough is made possible by application of a new 0.7  MW/54.5  GHz electron cyclotron resonance heating system in addition to standard 5 MW heating by neutral beams, and application of a radial electric field to mitigate the flute instability.
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.|Novosibirsk State University, 2 Pirogova str., 630090 Novosibirsk, Russia.
authors.forename: P A
authors.initials: PA
authors.lastname: Bagryansky
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.|Institute of Applied Physics, Russian Academy of Sciences, 46 Ulyanova str., 603950 Nizhny Novgorod, Russia.|Lobachevsky State University of Nizhny Novgorod, 23 Gagarina ave., 603950 N. Novgorod, Russia.
authors.forename: A G
authors.initials: AG
authors.lastname: Shalashov
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.|Institute of Applied Physics, Russian Academy of Sciences, 46 Ulyanova str., 603950 Nizhny Novgorod, Russia.|Lobachevsky State University of Nizhny Novgorod, 23 Gagarina ave., 603950 N. Novgorod, Russia.
authors.forename: E D
authors.initials: ED
authors.lastname: Gospodchikov
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.
authors.forename: A A
authors.initials: AA
authors.lastname: Lizunov
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.|Novosibirsk State University, 2 Pirogova str., 630090 Novosibirsk, Russia.
authors.forename: V V
authors.initials: VV
authors.lastname: Maximov
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.|Novosibirsk State University, 2 Pirogova str., 630090 Novosibirsk, Russia.
authors.forename: V V
authors.initials: VV
authors.lastname: Prikhodko
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.|Novosibirsk State University, 2 Pirogova str., 630090 Novosibirsk, Russia.
authors.forename: E I
authors.initials: EI
authors.lastname: Soldatkina
authors.affiliation: Budker Institute of Nuclear Physics, 11 Lavrentieva ave., 630090 Novosibirsk, Russia.|Novosibirsk State University, 2 Pirogova str., 630090 Novosibirsk, Russia.
authors.forename: A L
authors.initials: AL
authors.lastname: Solomakhin
authors.affiliation: Novosibirsk State University, 2 Pirogova str., 630090 Novosibirsk, Russia.
authors.forename: D V
authors.initials: DV
authors.lastname: Yakovlev