PAC2013 - List of Authors (Dudnikov, V.G.)

Paper	Title	Page
MOPAC26	Beam Brightness Booster with Ionization Cooling of Superintense Circulating Beams	123
	V.G. Dudnikov, C.M. Ankenbrandt, R.P. Johnson, L.G. Vorobiev Muons, Inc, Illinois, USA
	An increase of intensity and brightness of proton beam by means of charge exchange injection and devices developed for this experiment are considered. First observation of e-p instability, explanation and damping by feed back are discussed. Discovery of “cesiation effect” leading to multiple increase of negative ion emission from gas discharges and development of surface-plasma sources for intense high brightness negative ion beams production are considered. By these developments were prepared a possibility for production of stable “superintense” circulating beam with intensity and brightness fare above space charge limit. A beam brightness booster (BBB) for significant increase of accumulated beam brightness is discussed. New opportunity for simplification of the superintense beam production is promised by developing of nonlinear close to integrable focusing system with broad spread of betatron tune and the broad bend feed back system for e-p instability suppression. Effects of ionization cooling can be used for suppression of the beam particle scattering in the stripping target

TUPSM22	Improving Efficiency of Ions Production in Ion Source with Saddle Antenna	682
	V.G. Dudnikov, R.P. Johnson Muons, Inc, Illinois, USA T.R. Pennisi, C. Piller, M. Santana, M.P. Stockli, R.F. Welton ORNL, Oak Ridge, Tennessee, USA M.W. Turvey University of Florida, Gainesville, Florida, USA
	Funding: Work supported in part by US DOE Contract DE-AC05-00OR22725 and by STTR grant DE-SC0002690. Extraction of negative ions from RF surface plasma source (SPS) with saddle antenna radio frequency (SA RF) discharge is considered. Several versions of new plasma generators with different antennas and magnetic field configurations were tested in the SNS small Test Stand. The efficiency of positive ion generation in plasma has been improved up to ~90 mA/cm² per 1 kW of RF power at 13.56 MHz. For first cesiation was used a heating of the cesium chromate cartridges by CW RF discharge. A small oven for cesium compounds and alloys decomposition by heating was developed and tested. After cesiation a current of negative ions to the collector was increased from 0.5 mA to 10 mA with RF power ~ 1.5 kW in the plasma and longitudinal magnetic field Bl~250 Gauss. With increase of a longitudinal magnetic field the collector current can be increased up to 7 times. A stable long time generation of H⁻ beam without degradation was demonstrated in RF discharge with AlN discharge chamber.

WEPBA15	Ribbon Electron Beam Source for Bunched Beam Profile Monitor and Tomography	916
	V.G. Dudnikov, A. Dudas Muons, Inc, Illinois, USA A.V. Aleksandrov ORNL, Oak Ridge, Tennessee, USA
	Ribbon electron beam source with a strip cathode has been designed, fabricated and tested. Image of the ribbon electron beam with width up to 15 cm has been registered on the luminescent screen. This ribbon beam can be used for the large proton bunch profile monitoring in the Spallation Neutron Source (SNS) proton storage ring (PSR). Advanced beam diagnostics are essential for high performance accelerator beam production and for reliable accelerator operation. It is important to have noninvasive diagnostics which can be used continuously with intense beams of accelerated particles. In a novel proposed device for realization of electron probe tomography a strip cathode is used for ribbon electron beam formation instead of a scanning of pencil beam used in the previous electron probe bunch profile monitors. With this device it is possible to develop almost ideal tomography diagnostics of bunches in linear accelerators and in circular accelerators and storage rings.

Paper

Title

Page

Beam Brightness Booster with Ionization Cooling of Superintense Circulating Beams

123

V.G. Dudnikov, C.M. Ankenbrandt, R.P. Johnson, L.G. Vorobiev
Muons, Inc, Illinois, USA

An increase of intensity and brightness of proton beam by means of charge exchange injection and devices developed for this experiment are considered. First observation of e-p instability, explanation and damping by feed back are discussed. Discovery of “cesiation effect” leading to multiple increase of negative ion emission from gas discharges and development of surface-plasma sources for intense high brightness negative ion beams production are considered. By these developments were prepared a possibility for production of stable “superintense” circulating beam with intensity and brightness fare above space charge limit. A beam brightness booster (BBB) for significant increase of accumulated beam brightness is discussed. New opportunity for simplification of the superintense beam production is promised by developing of nonlinear close to integrable focusing system with broad spread of betatron tune and the broad bend feed back system for e-p instability suppression. Effects of ionization cooling can be used for suppression of the beam particle scattering in the stripping target

TUPSM22

Improving Efficiency of Ions Production in Ion Source with Saddle Antenna

682

V.G. Dudnikov, R.P. Johnson
Muons, Inc, Illinois, USA
T.R. Pennisi, C. Piller, M. Santana, M.P. Stockli, R.F. Welton
ORNL, Oak Ridge, Tennessee, USA
M.W. Turvey
University of Florida, Gainesville, Florida, USA

Funding: Work supported in part by US DOE Contract DE-AC05-00OR22725 and by STTR grant DE-SC0002690.
Extraction of negative ions from RF surface plasma source (SPS) with saddle antenna radio frequency (SA RF) discharge is considered. Several versions of new plasma generators with different antennas and magnetic field configurations were tested in the SNS small Test Stand. The efficiency of positive ion generation in plasma has been improved up to ~90 mA/cm² per 1 kW of RF power at 13.56 MHz. For first cesiation was used a heating of the cesium chromate cartridges by CW RF discharge. A small oven for cesium compounds and alloys decomposition by heating was developed and tested. After cesiation a current of negative ions to the collector was increased from 0.5 mA to 10 mA with RF power ~ 1.5 kW in the plasma and longitudinal magnetic field Bl~250 Gauss. With increase of a longitudinal magnetic field the collector current can be increased up to 7 times. A stable long time generation of H⁻ beam without degradation was demonstrated in RF discharge with AlN discharge chamber.

WEPBA15

Ribbon Electron Beam Source for Bunched Beam Profile Monitor and Tomography

916

V.G. Dudnikov, A. Dudas
Muons, Inc, Illinois, USA
A.V. Aleksandrov
ORNL, Oak Ridge, Tennessee, USA

Ribbon electron beam source with a strip cathode has been designed, fabricated and tested. Image of the ribbon electron beam with width up to 15 cm has been registered on the luminescent screen. This ribbon beam can be used for the large proton bunch profile monitoring in the Spallation Neutron Source (SNS) proton storage ring (PSR). Advanced beam diagnostics are essential for high performance accelerator beam production and for reliable accelerator operation. It is important to have noninvasive diagnostics which can be used continuously with intense beams of accelerated particles. In a novel proposed device for realization of electron probe tomography a strip cathode is used for ribbon electron beam formation instead of a scanning of pencil beam used in the previous electron probe bunch profile monitors. With this device it is possible to develop almost ideal tomography diagnostics of bunches in linear accelerators and in circular accelerators and storage rings.