title: Saddle antenna radio frequency ion sources.
abstract: Existing RF ion sources for accelerators have specific efficiencies for H(+) and H(-) ion generation ∼3-5 mA/cm(2) kW, where about 50 kW of RF power is typically needed for 50 mA beam current production. The Saddle Antenna (SA) surface plasma source (SPS) described here was developed to improve H(-) ion production efficiency, reliability, and availability. In SA RF ion source, the efficiency of positive ion generation in the plasma has been improved to 200 mA/cm(2) kW. After cesiation, the current of negative ions to the collector was increased from 1 mA to 10 mA with RF power ∼1.5 kW in the plasma (6 mm diameter emission aperture) and up to 30 mA with ∼4 kW RF. Continuous wave (CW) operation of the SA SPS has been tested on the test stand. The general design of the CW SA SPS is based on the pulsed version. Some modifications were made to improve the cooling and cesiation stability. CW operation with negative ion extraction was tested with RF power up to ∼1.2 kW in the plasma with production up to Ic = 7 mA. A stable long time generation of H(-) beam without degradation was demonstrated in RF discharge with AlN discharge chamber.
authors.affiliation: Muons, Inc., Batavia, Illinois 60510, USA.
authors.forename: V
authors.initials: V
authors.lastname: Dudnikov
authors.affiliation: Muons, Inc., Batavia, Illinois 60510, USA.
authors.forename: R
authors.initials: R
authors.lastname: Johnson
authors.affiliation: ORNL, Oak Ridge, Tennessee 37831, USA.
authors.forename: S
authors.initials: S
authors.lastname: Murray
authors.affiliation: ORNL, Oak Ridge, Tennessee 37831, USA.
authors.forename: T
authors.initials: T
authors.lastname: Pennisi
authors.affiliation: ORNL, Oak Ridge, Tennessee 37831, USA.
authors.forename: M
authors.initials: M
authors.lastname: Santana
authors.affiliation: ORNL, Oak Ridge, Tennessee 37831, USA.
authors.forename: C
authors.initials: C
authors.lastname: Piller
authors.affiliation: ORNL, Oak Ridge, Tennessee 37831, USA.
authors.forename: M
authors.initials: M
authors.lastname: Stockli
authors.affiliation: ORNL, Oak Ridge, Tennessee 37831, USA.
authors.forename: R
authors.initials: R
authors.lastname: Welton
authors.affiliation: TLU, Seguin, Texas 78155, USA.
authors.forename: J
authors.initials: J
authors.lastname: Breitschopf
authors.affiliation: UMD, College Park, Maryland 32611, USA.
authors.forename: G
authors.initials: G
authors.lastname: Dudnikova