RUPAC2012 - List of Keywords (plasma)

Paper	Title	Other Keywords	Page
MOXCH04	Laser-Plasma Acceleration – Towards a Compact X-ray Light Source and FEL	laser, acceleration, electron, FEL	9
	A. Seryi JAI, Oxford, United Kingdom
	Funding: The work is supported in part by UK STFC JAI grant ST/G008531. Advances in many scientific and technical fields depend on availability of instruments, which can probe the structure of materials or molecules on unprecedented levels of spatial or temporal resolution. Many of such instruments are based on accelerators of charged particles, with particular examples of synchrotron radiation light sources and coherent X-ray Free Electron Lasers. The high cost of such facilities, however, preclude wide spread of such instruments. Modern accelerator science witnesses emergence of a new direction – compact x-ray sources are coming to the scene, enabled by the synergy of accelerators and lasers, where high gradient laser-plasma acceleration can significantly reduce the size and cost of the facilities. Compact x-ray sources will be developed in the nearest future and will share their scientific and market niche with large national scale x-ray facilities. The compact sources will in particular be suitable for placement in universities and medical or technological centres. The compact x-ray light sources are being developed by many centres in UK. Development of compact x-ray FEL is a promising topic for scientific and technological collaboration between UK and Russia, where expertise of partners will cross-fertilize their ability to solve scientific and technological challenges.
	Slides MOXCH04 [12.555 MB]

FRBOR01	Progress in the Negative Ion Sources Development	ion, ion-source, cathode, brightness	213
	V.G. Dudnikov Muons, Inc, Batavia, USA
	Modern trends and recent progress in development of negative ion sources will be considered and analyzed. Surface Plasma Sources (SPS) rely on cesium-enhanced plasma surface reactions to produce negative ions are main sources delivering the negative ion beam for charge exchange injection in accelerators and fusion devices. After development of the SPS with cesiation the negative ion beam intensity has increased up to ~10⁴ times, from a record 3 mA to more than 40 A. Since the original conception of SPS with cesiation, many modifications and improvements have been made such that they constitute a mature and reliable technology today. The world-wide effort on the development and use of SPS with cesiation has increased to more than a thousand highly qualified scientists, engineers, technicians, workers, and administrators. The cost scale of advanced SPS has increased from ~ k to ~ M. SPS with cesiation have become "sources of life" and "working horses" for big installations such as SNS, LANSCE, BNL, FNAL, ISIS, KEK, JT 60 (Japanese tokamak), and the LHD (Large Helicon Device). Large development projects include the SPS for the Large Hadron Collider (LHC) and for the International Thermonuclear Experimental Reactor (ITER). The development and fabrication of injectors with cesiated SPS has become a billion dollar scale industry.
	Slides FRBOR01 [8.083 MB]

FRBCH07	Transformation of Beams in the Plasma Lens and Investigation of Z-Pinch Dynamics	ion, focusing, simulation, laser	239
	A.A. Drozdovsky, N.N. Alexeev, S.A. Drozdovsky, A. Golubev, Yu.B. Novozhilov, P.V. Sasorov, S.M. Savin, V.V. Yanenko ITEP, Moscow, Russia
	Funding: Work supported by the Russian Foundation for Basic Research The plasma lens can carry out sharp focusing of ion beam with considerable reduction sizes of focal spot. At those stages of the plasma discharge at which the magnetic field is nonlinear, formation of other interesting configurations of beams is possible. The report presents the results of studies transformation the Gaussian beam into hollow one and into beam with homogeneous spatial distribution. The discharge current distributions obtained by numerical calculation ensure the experimental beam transformations. Thus possibility of the research of the plasma discharge dynamics by means of relativistic ions beams is shown. The plasma lens represents the universal device for scientific and technical applications in particular for irradiation of medical objects.
	Slides FRBCH07 [1.390 MB]

MOPPA001	Excitation of the Focusing Wakefields by a Relativistic Bunch in Isotropic Capillary Discharge Plasma	focusing, wakefield, electron, vacuum	242
	R.R. Kniaziev, G.V. Sotnikov NSC/KIPT, Kharkov, Ukraine
	At present work excitation of wakefields by an relativistic electron bunch in a capillary tube filled with plasma is investigated. In the approximation of constant velocity of the bunches an analytical expressions for a components of an electromagnetic field are found. Numerical calculations of excited capillary tubes fields fabricated from the alumina and the quartz is carried out. Outer diameter of a capillary tube is equal 1 mm, inner diameter is 0.4 mm. In the absence of plasma in such structure the wakefields of the THz frequencies range are excited. Longitudinal and transverse profiles of wake fields in slow wave structure which drive channel is filled with plasma are investigated in details. These profiles allow to investigate dependences of wakefields from plasma density, the sizes of dielectric structure and/or the linear sizes of an electron bunch. When comparison of these dependences, it follows that there are longitudinal positions of the test bunch relative to the drive bunch, which can provide high-gradient acceleration of charged particles and their simultaneous radial focusing.

MOPPA004	Energy Spread Decreasing in Linear Mode Operating Laser Plasma Wakefield Accelerator	electron, laser, acceleration, bunching	251
	S.M. Polozov MEPhI, Moscow, Russia
	Laser plasma wakefield acceleration (LPWA)* is one of most popular novel methods of acceleration. The LPWA is very perceptively because the accelerating gradient in plasma channel can be a number of orders larger than in metal structures. But the LPWA has two serous disadvantages as very high energy spread and low part of electrons trapped into acceleration. The energy spectrum better than 10% does not observed anyone in simulations or experiments. It should be noted that the electron's beam dynamics in LPWA is different for underdense plasma (quasi linear mode) and in for dense plasma (non-linear and bubble modes). Non-linear mode is studying more intensive at present and methods of the energy spread decrease are under development ,. But the linear LPWA mode also has interest for practical use. The rate of energy gain is very high in the linear mode also and compact laboratory scale facility could be designed to accelerate the electron beam up to a hundreds MeV. Bunching before injection into plasma channel will discuss to decrease the energy spread and to enlarge the electron trapping efficiency. T. Tajima, J.M. Dowson. Phys. Rev. Lett., 1979, v. 43, 4, 267. S.V. Bulanovet al. Physics of Plasmas, 2008, 15, 073111. * E.Esarey et al. Phys. Rev. Lett., 1997, 79, 2682.

MOPPA005	Laser-Wakefield Acceleration with External Bunch Injection at REGAE	laser, electron, emittance, injection	254
	J. Grebenyuk, K. Flöttmann DESY, Hamburg, Germany T. Mehrling, J. Osterhoff Uni HH, Hamburg, Germany
	Funding: Helmholtz Alliance Short and highly intense laser pulses focused into a gas target, ionise the gas and may excite large amplitude plasma waves that support extreme electric fields (>10 GV/m) for acceleration of charged particles. The REGAE facility at DESY, which provides 2-5 MeV of ~10 fs bunches, offers the unique possibility to study the external injection of pre-accelerated electron bunches from a conventional accelerator, and their subsequent acceleration in plasma wakefields. Simulations were performed with the particle-in-cell code OSIRIS, showing a wide variety of effects which can be explored in the future at REGAE. External controlled injection allows to study effects which require precise information about the beam quality, position and momentum at the initial point of injection. Topics of a particular interest are: bunch emittance growth suppression, controlled betatron motion, and longitudinal bunch compression.

MOPPA007	Wakefield Produced by a Small Bunch Moving in Cold Magnetized Plasma Along the External Magnetic Field	wakefield, acceleration, electromagnetic-fields, electron	257
	S.N. Galyamin, D.Y. Kapshtan, A.V. Tyukhtin Saint-Petersburg State University, Saint-Petersburg, Russia
	Funding: The Dmitry Zimin "Dynasty" Foundation and Russian Foundation for Basic Research (Grant No. 12-02-31258). Plasma wakefield acceleration (PWFA) is a promising tool for acceleration of charged particles to high energies at relatively small lengths. Knowledge about the structure of the electromagnetic field produced by the driver bunch in plasma plays the essential role for the realization of this accelerating scheme. Constant external magnetic field which can be used for focusing the driver bunch affects the field structure essentially because plasma acquires both anisotropy and gyrotropy. However, the electromagnetic field in the latter case has not been practically investigated until present. Here we study the field produced by point charge and small bunch moving in cold magnetized plasma along the external magnetic field. We note the singular behavior of some components of the wave field produced by point charge near the charge trajectory. We also analyze the influence of the external magnetic field and bunch size on the field components.

TUPPB006	Compression and Confinement of Positron Clouds in the Surko Trap of LEPTA Facility	accumulation, positron, resonance, focusing	319
	M.K. Eseev, A.N. Vititnev NAFU, Arkhangelsk, Russia E.V. Ahmanova, A.G. Kobets, I.N. Meshkov, A.Yu. Rudakov, S. Yakovenko JINR, Dubna, Moscow Region, Russia
	A bunch of positrons confined in a cylindrical Penning-Malmberg trap can be compressed radially by applying a rotating asymmetric dipolar electric field. An explanation of this effect presented in the report is based on the solutions of particle 3D dynamics equations in the fields of the trap taking into account the positron collisions with a neutral buffer gas. The result agrees well with experimental data obtained at the positron injector of LEPTA facility at JINR. Essential feature of the compression process is resonant character of applied rotating field and coincidence its frequency with the frequency of longitudinal positron bouncing in the trap.

TUPPB033	Simplified Beam Line with Space Charge Compensation of Low Energy Ion Beam	ion, space-charge, ion-source, electron	388
	A.V. Dudnikov BINP SB RAS, Novosibirsk, Russia
	Simplified beam line for low energy Ion implantation is considered. Compensation of the space charge of high perveance, low energy ion beam in beam lines for ion implantation and isotope separation has been investigated. Space charge compensation and overcompensation by ions will be considered. Different mechanisms of the compensating particle formation such as ionization by the beam, secondary emission of electrons and negative ions, electronegative gas admixture, and external plasma sources will be discussed. Advanced space charge compensation increases an intensity of low energy ion beam after analyzer magnet up to 3–4 times. Space charge compensation of positive ion beam by admixture of electronegative gases and damping of the beam instability will be discussed. Up to 6 mA of 11B+ ions with energy 3 keV, 11 mA with 5 keV, and 18 mA with 10 keV have been transported through an analyzer magnet of a high current implanter with space charge compensation by electronegative gases

TUPPB039	The Motion of Ionic Flux in an Electron Layer	electron, ion, extraction, vacuum	403
	A.S. Chikhachev, Y.A. Kovalenko Allrussian Electrotechnical Institute, Moskow, Russia
	Processes of ion extraction from plasma are very important for experiment. This process is studied in a lot of theoretical works. In work * was shown that ions leave plasma with velocities, exceeding ion-sound velocity. In real conditions when electron temperature exceeds the ion temperature, quantity ions accelerated is exponentially small. In work was shown that transition layer in system "plasma-vacuum" are infinitely great. In * equilibrium states with nonzero flow of electrons are studied, where electrons and ions have the same drift direction. In presented work equilibrium states are studied when nonzero electron flow has drift direction perpendicular to ion drift direction. States were examined with finite thickness and in condition of electrons, occupying half of the layer. * K.-U.Riemann, J.Phys. D, 1991, 24, 493. N.Sternberg, V.Godyak, IEEE Plasma Sc., 35, 2007, 1341. * Yu.A.Kovalenko, T.V.Chernyshev, A.S.Chikhachev, Izv. RAN, "Energetika", 2011, 4, 24.

TUPPB053	High Duty Cycle Ion Sources at GSI and FAIR	ion, ion-source, ECRIS, electron	433
	J. Pfister, A. Adonin, W.A. Barth, R. Hollinger, K. Tinschert GSI, Darmstadt, Germany
	Future heavy ion experiments at GSI and FAIR demand for high current as well as highly brilliant ion beams of various metallic and gaseous ions produced by the GSI accelerator facility. Therefore GSI's Ion Source Group is developing and operating various types of ion sources feeding the linac at 2.2keV/u with a maximum mass-over-charge ratio of 65. In this contribution a status overview of operated high duty cycle ion sources including important ion source data as beam current, beam spectrum, transverse emittance, duty factor and transmission along the LEBT as well as future perspectives for the ion source operation for FAIR is presented.

TUPPB054	High Current Ion Sources for the FAIR Accelerator Facility	ion, ion-source, injection, extraction	436
	R. Hollinger, A. Adonin, W.A. Barth, J. Pfister GSI, Darmstadt, Germany N. Chauvin CEA/DSM/IRFU, France
	Vacuum Arc Ion Sources and filament driven Multi Cusp Ion Sources are used for the production of high current ion beams of a variety of metallic and gaseous ions at the GSI accelerator facility. For the future project FAIR (Facility of Antiproton and Ion Research) it is foreseen to provide in addition a high current proton beam and an exclusive uranium beam from two new ion source injectors. The contribution gives an overview of the performance of the existing high current injector and presents the challenges for the future injectors for proton and uranium production.

TUPPB058	Improving Efficiency of Plasma Generation in H⁻ Ion Source with Saddle Antenna	ion, ion-source, gun, electron	439
	V.G. Dudnikov, R.P. Johnson Muons, Inc, Batavia, USA S.N. Murray, T.R. Pennisi, M.F. Piller, M. Santana, M.P. Stockli, R.F. Welton ORNL, Oak Ridge, Tennessee, USA
	Funding: Work supported in part by US DOE Contract DE-AC05-00OR22725 and by STTR grant DE-SC0002690. Progress in development of RF ion source with saddle radio frequency (SA) (RF) antenna which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability is considered. Several versions of new plasma generators with different antennas and magnetic field configurations were tested in the Test Stand. The efficiency of positive ion plasma generation has been improved ~4x times up to 0.18 A/cm² per 1 kW of RF power 13.56 MHz. A new version of the RF assisted triggering plasma source (TPS) has been designed, fabricated and tested. A Saddle antenna SPS with water cooling is being fabricated for high duty factor have been tested.

WEPPD050	Approximate Method for Calculation of Field of Charged Particle Moving through Dielectric Object	radiation, vacuum, diagnostics, simulation	656
	E.S. Belonogaya, S.N. Galyamin, A.V. Tyukhtin Saint-Petersburg State University, Saint-Petersburg, Russia
	Cherenkov radiation is widely used for particle detection. As well, it is prospective for particle bunch diagnostics. Therefore, it is actual to elaborate methods for calculation of the fields of bunches moving in the presence of different dielectric objects. We offer the approximate method based on calculation of the field in unbounded medium and accounting of boundary influence by geometrical optics. First, we consider the problem concerning the field of charge crossing a dielectric plate. This problem has an exact solution. It is used as a "test" problem for estimation of precision of the approximate method. Computation of the field is performed using both methods and the results have a good agreement. Further, we analyze the cases of more complex objects, in particular, a dielectric cone. Note, that the offered method allows to obtain wave fields using neither complex analytical transformations nor laborious numerical calculations.

Paper

Title

Other Keywords

Page

MOXCH04

Laser-Plasma Acceleration – Towards a Compact X-ray Light Source and FEL

laser, acceleration, electron, FEL

9

A. Seryi
JAI, Oxford, United Kingdom

Funding: The work is supported in part by UK STFC JAI grant ST/G008531.
Advances in many scientific and technical fields depend on availability of instruments, which can probe the structure of materials or molecules on unprecedented levels of spatial or temporal resolution. Many of such instruments are based on accelerators of charged particles, with particular examples of synchrotron radiation light sources and coherent X-ray Free Electron Lasers. The high cost of such facilities, however, preclude wide spread of such instruments. Modern accelerator science witnesses emergence of a new direction – compact x-ray sources are coming to the scene, enabled by the synergy of accelerators and lasers, where high gradient laser-plasma acceleration can significantly reduce the size and cost of the facilities. Compact x-ray sources will be developed in the nearest future and will share their scientific and market niche with large national scale x-ray facilities. The compact sources will in particular be suitable for placement in universities and medical or technological centres. The compact x-ray light sources are being developed by many centres in UK. Development of compact x-ray FEL is a promising topic for scientific and technological collaboration between UK and Russia, where expertise of partners will cross-fertilize their ability to solve scientific and technological challenges.

Slides MOXCH04 [12.555 MB]

FRBOR01

Progress in the Negative Ion Sources Development

ion, ion-source, cathode, brightness

213

V.G. Dudnikov
Muons, Inc, Batavia, USA

Modern trends and recent progress in development of negative ion sources will be considered and analyzed. Surface Plasma Sources (SPS) rely on cesium-enhanced plasma surface reactions to produce negative ions are main sources delivering the negative ion beam for charge exchange injection in accelerators and fusion devices. After development of the SPS with cesiation the negative ion beam intensity has increased up to ~10⁴ times, from a record 3 mA to more than 40 A. Since the original conception of SPS with cesiation, many modifications and improvements have been made such that they constitute a mature and reliable technology today. The world-wide effort on the development and use of SPS with cesiation has increased to more than a thousand highly qualified scientists, engineers, technicians, workers, and administrators. The cost scale of advanced SPS has increased from ~ k to ~ M. SPS with cesiation have become "sources of life" and "working horses" for big installations such as SNS, LANSCE, BNL, FNAL, ISIS, KEK, JT 60 (Japanese tokamak), and the LHD (Large Helicon Device). Large development projects include the SPS for the Large Hadron Collider (LHC) and for the International Thermonuclear Experimental Reactor (ITER). The development and fabrication of injectors with cesiated SPS has become a billion dollar scale industry.

Slides FRBOR01 [8.083 MB]

FRBCH07

Transformation of Beams in the Plasma Lens and Investigation of Z-Pinch Dynamics

ion, focusing, simulation, laser

239

A.A. Drozdovsky, N.N. Alexeev, S.A. Drozdovsky, A. Golubev, Yu.B. Novozhilov, P.V. Sasorov, S.M. Savin, V.V. Yanenko
ITEP, Moscow, Russia

Funding: Work supported by the Russian Foundation for Basic Research
The plasma lens can carry out sharp focusing of ion beam with considerable reduction sizes of focal spot. At those stages of the plasma discharge at which the magnetic field is nonlinear, formation of other interesting configurations of beams is possible. The report presents the results of studies transformation the Gaussian beam into hollow one and into beam with homogeneous spatial distribution. The discharge current distributions obtained by numerical calculation ensure the experimental beam transformations. Thus possibility of the research of the plasma discharge dynamics by means of relativistic ions beams is shown. The plasma lens represents the universal device for scientific and technical applications in particular for irradiation of medical objects.

Slides FRBCH07 [1.390 MB]

MOPPA001

Excitation of the Focusing Wakefields by a Relativistic Bunch in Isotropic Capillary Discharge Plasma

focusing, wakefield, electron, vacuum

242

R.R. Kniaziev, G.V. Sotnikov
NSC/KIPT, Kharkov, Ukraine

At present work excitation of wakefields by an relativistic electron bunch in a capillary tube filled with plasma is investigated. In the approximation of constant velocity of the bunches an analytical expressions for a components of an electromagnetic field are found. Numerical calculations of excited capillary tubes fields fabricated from the alumina and the quartz is carried out. Outer diameter of a capillary tube is equal 1 mm, inner diameter is 0.4 mm. In the absence of plasma in such structure the wakefields of the THz frequencies range are excited. Longitudinal and transverse profiles of wake fields in slow wave structure which drive channel is filled with plasma are investigated in details. These profiles allow to investigate dependences of wakefields from plasma density, the sizes of dielectric structure and/or the linear sizes of an electron bunch. When comparison of these dependences, it follows that there are longitudinal positions of the test bunch relative to the drive bunch, which can provide high-gradient acceleration of charged particles and their simultaneous radial focusing.

MOPPA004

Energy Spread Decreasing in Linear Mode Operating Laser Plasma Wakefield Accelerator

electron, laser, acceleration, bunching

251

S.M. Polozov
MEPhI, Moscow, Russia

Laser plasma wakefield acceleration (LPWA)* is one of most popular novel methods of acceleration. The LPWA is very perceptively because the accelerating gradient in plasma channel can be a number of orders larger than in metal structures. But the LPWA has two serous disadvantages as very high energy spread and low part of electrons trapped into acceleration. The energy spectrum better than 10% does not observed anyone in simulations or experiments. It should be noted that the electron's beam dynamics in LPWA is different for underdense plasma (quasi linear mode) and in for dense plasma (non-linear and bubble modes). Non-linear mode is studying more intensive at present and methods of the energy spread decrease are under development **,***. But the linear LPWA mode also has interest for practical use. The rate of energy gain is very high in the linear mode also and compact laboratory scale facility could be designed to accelerate the electron beam up to a hundreds MeV. Bunching before injection into plasma channel will discuss to decrease the energy spread and to enlarge the electron trapping efficiency.
* T. Tajima, J.M. Dowson. Phys. Rev. Lett., 1979, v. 43, 4, 267.
** S.V. Bulanovet al. Physics of Plasmas, 2008, 15, 073111.
*** E.Esarey et al. Phys. Rev. Lett., 1997, 79, 2682.

MOPPA005

Laser-Wakefield Acceleration with External Bunch Injection at REGAE

laser, electron, emittance, injection

254

J. Grebenyuk, K. Flöttmann
DESY, Hamburg, Germany
T. Mehrling, J. Osterhoff
Uni HH, Hamburg, Germany

Funding: Helmholtz Alliance
Short and highly intense laser pulses focused into a gas target, ionise the gas and may excite large amplitude plasma waves that support extreme electric fields (>10 GV/m) for acceleration of charged particles. The REGAE facility at DESY, which provides 2-5 MeV of ~10 fs bunches, offers the unique possibility to study the external injection of pre-accelerated electron bunches from a conventional accelerator, and their subsequent acceleration in plasma wakefields. Simulations were performed with the particle-in-cell code OSIRIS, showing a wide variety of effects which can be explored in the future at REGAE. External controlled injection allows to study effects which require precise information about the beam quality, position and momentum at the initial point of injection. Topics of a particular interest are: bunch emittance growth suppression, controlled betatron motion, and longitudinal bunch compression.

MOPPA007

Wakefield Produced by a Small Bunch Moving in Cold Magnetized Plasma Along the External Magnetic Field

wakefield, acceleration, electromagnetic-fields, electron

257

S.N. Galyamin, D.Y. Kapshtan, A.V. Tyukhtin
Saint-Petersburg State University, Saint-Petersburg, Russia

Funding: The Dmitry Zimin "Dynasty" Foundation and Russian Foundation for Basic Research (Grant No. 12-02-31258).
Plasma wakefield acceleration (PWFA) is a promising tool for acceleration of charged particles to high energies at relatively small lengths. Knowledge about the structure of the electromagnetic field produced by the driver bunch in plasma plays the essential role for the realization of this accelerating scheme. Constant external magnetic field which can be used for focusing the driver bunch affects the field structure essentially because plasma acquires both anisotropy and gyrotropy. However, the electromagnetic field in the latter case has not been practically investigated until present. Here we study the field produced by point charge and small bunch moving in cold magnetized plasma along the external magnetic field. We note the singular behavior of some components of the wave field produced by point charge near the charge trajectory. We also analyze the influence of the external magnetic field and bunch size on the field components.

TUPPB006

Compression and Confinement of Positron Clouds in the Surko Trap of LEPTA Facility

accumulation, positron, resonance, focusing

319

M.K. Eseev, A.N. Vititnev
NAFU, Arkhangelsk, Russia
E.V. Ahmanova, A.G. Kobets, I.N. Meshkov, A.Yu. Rudakov, S. Yakovenko
JINR, Dubna, Moscow Region, Russia

A bunch of positrons confined in a cylindrical Penning-Malmberg trap can be compressed radially by applying a rotating asymmetric dipolar electric field. An explanation of this effect presented in the report is based on the solutions of particle 3D dynamics equations in the fields of the trap taking into account the positron collisions with a neutral buffer gas. The result agrees well with experimental data obtained at the positron injector of LEPTA facility at JINR. Essential feature of the compression process is resonant character of applied rotating field and coincidence its frequency with the frequency of longitudinal positron bouncing in the trap.

TUPPB033

Simplified Beam Line with Space Charge Compensation of Low Energy Ion Beam

ion, space-charge, ion-source, electron

388

A.V. Dudnikov
BINP SB RAS, Novosibirsk, Russia

Simplified beam line for low energy Ion implantation is considered. Compensation of the space charge of high perveance, low energy ion beam in beam lines for ion implantation and isotope separation has been investigated. Space charge compensation and overcompensation by ions will be considered. Different mechanisms of the compensating particle formation such as ionization by the beam, secondary emission of electrons and negative ions, electronegative gas admixture, and external plasma sources will be discussed. Advanced space charge compensation increases an intensity of low energy ion beam after analyzer magnet up to 3–4 times. Space charge compensation of positive ion beam by admixture of electronegative gases and damping of the beam instability will be discussed. Up to 6 mA of 11B+ ions with energy 3 keV, 11 mA with 5 keV, and 18 mA with 10 keV have been transported through an analyzer magnet of a high current implanter with space charge compensation by electronegative gases

TUPPB039

The Motion of Ionic Flux in an Electron Layer

electron, ion, extraction, vacuum

403

A.S. Chikhachev, Y.A. Kovalenko
Allrussian Electrotechnical Institute, Moskow, Russia

Processes of ion extraction from plasma are very important for experiment. This process is studied in a lot of theoretical works. In work * was shown that ions leave plasma with velocities, exceeding ion-sound velocity. In real conditions when electron temperature exceeds the ion temperature, quantity ions accelerated is exponentially small. In work ** was shown that transition layer in system "plasma-vacuum" are infinitely great. In *** equilibrium states with nonzero flow of electrons are studied, where electrons and ions have the same drift direction. In presented work equilibrium states are studied when nonzero electron flow has drift direction perpendicular to ion drift direction. States were examined with finite thickness and in condition of electrons, occupying half of the layer.
* K.-U.Riemann, J.Phys. D, 1991, 24, 493.
** N.Sternberg, V.Godyak, IEEE Plasma Sc., 35, 2007, 1341.
*** Yu.A.Kovalenko, T.V.Chernyshev, A.S.Chikhachev, Izv. RAN, "Energetika", 2011, 4, 24.

TUPPB053

High Duty Cycle Ion Sources at GSI and FAIR

ion, ion-source, ECRIS, electron

433

J. Pfister, A. Adonin, W.A. Barth, R. Hollinger, K. Tinschert
GSI, Darmstadt, Germany

Future heavy ion experiments at GSI and FAIR demand for high current as well as highly brilliant ion beams of various metallic and gaseous ions produced by the GSI accelerator facility. Therefore GSI's Ion Source Group is developing and operating various types of ion sources feeding the linac at 2.2keV/u with a maximum mass-over-charge ratio of 65. In this contribution a status overview of operated high duty cycle ion sources including important ion source data as beam current, beam spectrum, transverse emittance, duty factor and transmission along the LEBT as well as future perspectives for the ion source operation for FAIR is presented.

TUPPB054

High Current Ion Sources for the FAIR Accelerator Facility

ion, ion-source, injection, extraction

436

R. Hollinger, A. Adonin, W.A. Barth, J. Pfister
GSI, Darmstadt, Germany
N. Chauvin
CEA/DSM/IRFU, France

Vacuum Arc Ion Sources and filament driven Multi Cusp Ion Sources are used for the production of high current ion beams of a variety of metallic and gaseous ions at the GSI accelerator facility. For the future project FAIR (Facility of Antiproton and Ion Research) it is foreseen to provide in addition a high current proton beam and an exclusive uranium beam from two new ion source injectors. The contribution gives an overview of the performance of the existing high current injector and presents the challenges for the future injectors for proton and uranium production.

TUPPB058

Improving Efficiency of Plasma Generation in H⁻ Ion Source with Saddle Antenna

ion, ion-source, gun, electron

439

V.G. Dudnikov, R.P. Johnson
Muons, Inc, Batavia, USA
S.N. Murray, T.R. Pennisi, M.F. Piller, M. Santana, M.P. Stockli, R.F. Welton
ORNL, Oak Ridge, Tennessee, USA

Funding: Work supported in part by US DOE Contract DE-AC05-00OR22725 and by STTR grant DE-SC0002690.
Progress in development of RF ion source with saddle radio frequency (SA) (RF) antenna which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability is considered. Several versions of new plasma generators with different antennas and magnetic field configurations were tested in the Test Stand. The efficiency of positive ion plasma generation has been improved ~4x times up to 0.18 A/cm² per 1 kW of RF power 13.56 MHz. A new version of the RF assisted triggering plasma source (TPS) has been designed, fabricated and tested. A Saddle antenna SPS with water cooling is being fabricated for high duty factor have been tested.

WEPPD050

Approximate Method for Calculation of Field of Charged Particle Moving through Dielectric Object

radiation, vacuum, diagnostics, simulation

656

E.S. Belonogaya, S.N. Galyamin, A.V. Tyukhtin
Saint-Petersburg State University, Saint-Petersburg, Russia

Cherenkov radiation is widely used for particle detection. As well, it is prospective for particle bunch diagnostics. Therefore, it is actual to elaborate methods for calculation of the fields of bunches moving in the presence of different dielectric objects. We offer the approximate method based on calculation of the field in unbounded medium and accounting of boundary influence by geometrical optics. First, we consider the problem concerning the field of charge crossing a dielectric plate. This problem has an exact solution. It is used as a "test" problem for estimation of precision of the approximate method. Computation of the field is performed using both methods and the results have a good agreement. Further, we analyze the cases of more complex objects, in particular, a dielectric cone. Note, that the offered method allows to obtain wave fields using neither complex analytical transformations nor laborious numerical calculations.