Operation of TFTR neutral beams with heavy ions

Technical Report · Mon Jul 01 04:00:00 EDT 1991

DOI:https://doi.org/10.2172/5455855· OSTI ID:5455855

Kamperschroer, J H; Stevenson, T N; Wright, K E; Dudek, L E; Grisham, L R; Newman, R A; O'Connor, T E; Oldaker, M E; von Halle, A; Williams, M D

High Z neutral atoms have been injected into TFTR plasmas in an attempt to enhance plasma confinement through modification of the edge electric field. TFTR ion sources have extracted 9 A of 62 keV Ne{sup +} for up to 0.2 s during injection into deuterium plasmas, and for 0.5 s during conditioning pulses. Approximately 400 kW of Ne{sup 0} have been injected from each of two ion sources. Operation was at full bending magnet current, with the Ne{sup +} barely contained on the ion dump. Beamline design modifications to permit operation up to 120 keV with krypton or xenon are described. Such ions are too massive to be deflected up to the ion dump. The plan, therefore, is to armor those components receiving these ions. Even with this armor, modest increases in the bending magnet current capability are necessary to safely reach 120 kV with Kr or Xe. Information relevant to heavy ion operation was also acquired when several ion sources were inadvertently operated with water contamination. Spectroscopic analysis of certain pathological pulses indicate that up to 6% of the extracted ions were water. After dissociation in the neutralizer, water yields oxygen ions which, as with Ne, Kr, and Xe, are under-deflected by the magnet. Damage to a calorimeter scraper, due to the focal properties of the magnet, has resulted. A magnified power density of 6 KW/cm{sup 2} for 2 s, from {approximately} 90 kW of O{sup +}, is the suspected cause. 11 refs., 4 figs.

• Research Organization: Princeton Univ., NJ (United States). Plasma Physics Lab.
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 5455855
• Report Number(s): PPPL-2781; ON: DE91016213
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101 -- Fusion Energy-- Plasma Research-- Confinement
Heating
& Production
700205* -- Fusion Power Plant Technology-- Fuel
Heating
& Injection Systems
BEAM INJECTION
CHARGED PARTICLES
DEUTERIUM
HYDROGEN COMPOUNDS
HYDROGEN ISOTOPES
IMPURITIES
ION SOURCES
IONS
ISOTOPES
KRYPTON IONS
LIGHT NUCLEI
NEON IONS
NEUTRAL ATOM BEAM INJECTION
NUCLEI
ODD-ODD NUCLEI
OXYGEN COMPOUNDS
PLASMA IMPURITIES
STABLE ISOTOPES
TFTR TOKAMAK
THERMONUCLEAR REACTORS
TOKAMAK TYPE REACTORS
WATER
XENON IONS