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CAT-KEK SOKENDAI School on Spallation Neutron Source: Accelerator Physics & Technological Aspects February 2 – 8, 2004, Centre for Advanced Technology, Indore, India. ION SOURCES. Akira Takagi. KEK (High Energy Accelerator Organization), Japan. ION SOURCES(2).
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CAT-KEK SOKENDAI School on Spallation Neutron Source: Accelerator Physics &Technological Aspects February 2 – 8, 2004, Centre for Advanced Technology, Indore, India ION SOURCES Akira Takagi KEK (High Energy Accelerator Organization), Japan
ION SOURCES(2) • Volume Production Negative Hydrogen Source Early results in KEK Recent results for J-PARC • H- Diagnostics (with laser) • References
Production Processes of Negative Hydrogen ions in Hydrogen Plasma • Dissociative Attachment H2*(v) + e(~1eV) H- + H s = 4.3x10-16 cm2 Esmax = ~0.4 eV • Dissociative Recombination H2+ + e H- + H+s = 1x10-17 cm2 Esmax = 3 eV H3+ + e H- + H2+s = 1.6x10-18 cm2 Esmax = 7.5 eV • Polar Dissociation H2 + e H- + H+ + e s = 1.7x10-20 cm2 Esmax = 38 eV • Radiative Capture H + e H- + hns = 2.6x10-22 cm2 Esmax = 0.7 eV
Destruction Processes of Negative Hydrogen ions in Hydrogen Plasma • Collisional Detachment H-+ ef H + 2e s = 4.3x10-15 cm2 Esmax = 15 eV H-+ H 2H + e s = 1.6x10-15 cm2 Esmax = 500 eV H-+ H2 H + H2 + e s = 10-15 cm2 Esmax = 10-4 eV • Charge transfer H- + H+ 2H-s = 2.5x10-13 cm2 Esmax = 0.15 eV (c.m.)
Volume Production Negative Hydrogen Source • Early results in KEK • Recent results for J-PARC
New Surface Production Dominating Cs-Free H- Ion Source(J-PARC)
Beam Diagnostics for H- BeamApplication of Laser Stripping(Electron Affinity = 0.75 eV)
Lorentz Transformation • ECM : the photon energy in the H- rest frame ECM = gEL[1 – bcos(JL)] Laser beam H- beamJL H-, Ho, e-
Beam Energy Analyser (LASL)Fechbach Resonance(n=2)(Dissisiative Resonance)
REFERENCES • A. Ueno, et al.,”Surface Production Dominating Cs-Free H- Ion Source for High Intensity and High Energy Accelerators” 10th internatinal Conference on Ion Sources, Dubma (2003). • H. Oguri, “Study of High Intensity Negative Ion Source” Thesis, Sokendai. • O. R. Sander, “Transverse emittance: its definition, application, and measurement” AIP Conference Proc. 212, Accelerator Instrumentation Workshop • R. E. Shafer, “Laser Diagnostic for High current H0 Beams” LINAC’98.
BIBLIOGRAPHY Ion Source • R. H. Huddlestone and S. L. Leonard, “Plasma Diagnostic Techniques” (1965) Academic Press. • R. G. Wilson and G. R. Brewer, “Ion Beams-with Application to Ion Implantation” (1973) John Wiley & Sons, Inc. • L. Valyi, “Atom and Ion Sources” (1977) John Wiley & Sons, Inc.. • J. R. Roth, “Industrial Plasma Engineering-Volume 1;Plinciples” (1995) Institute of Physics Publishing. • Bernhard Wolf (Editor), “Handbook of Ion Sources” (1995) CRC Press Inc. Other • R. H. Thomas and G. R. Stevenson, “Radiological Safety Aspects of the Operation of Proton Accelerators” (1988) Technical reports series no. 283, IAEA, VIENNA. • J. D. Cossairt, “Radiation Physics for Personal and Environmental Protection, Revision 5” (2001), FELMILAB-TM-1834, Revision 5. • M. Awschalom and T. Borak, “The Effect of Radiation on Electrical Insulating Materials” (1969), FELMILAB-TM-183. • H. Schonbacher and M. Tavlet, “Compilation of Radiation Damage Test Data, Part 1, 2nd edition: Halogen-free cable-insulating materials” (1989) CERN 89-12 • M. Tavlet and H. Schonbacher , “Compilation of Radiation Damage Test Data, Part 1, 2nd edition: Thermoset and thermoplastic resins, composites. materials” (1998) CERN 98-1.
Other Useful Reports (pdf files) Radiation • R. H. Thomas and G. R. Stevenson, “Radiological Safety Aspects of the Operation of Proton Accelerators” (1988) Technical reports series no. 283, IAEA, VIENNA. • J. D. Cossairt, “Radiation Physics for Personal and Environmental Protection, Revision 5” (2001), FELMILAB-TM-1834, Revision 5. • M. Awschalom and T. Borak, “The Effect of Radiation on Electrical Insulating Materials” (1969), FELMILAB-TM-183. • H. Schonbacher and M. Tavlet, “Compilation of Radiation Damage Test Data, Part 1, 2nd edition: Halogen-free cable-insulating materials” (1989) CERN 89-12 • M. Tavlet and H. Schonbacher , “Compilation of Radiation Damage Test Data, Part 1, 2nd edition: Thermoset and thermoplastic resins, composites. materials” (1998) CERN 98-1. Power Supply • W. North, “High-Power Microwave-Tube Transmitters” (1994), Los Alamos, LA-12687-MS. SNS, KEK • SNS CDR (1997) • BNL/SNS Technical Note • JKJ TDR (July, 2002)
CONCULUSIONS • Various Types of H- Ion Source • KEK Surface H- Ion Source • LaB6 Filament • Secondary Electron by Ion/H- Impact • Beam Chopping • Volume H- Ion Sources (J-PARC) • Beam Diagnostics for H- Beam