Design and operation of the pellet charge exchange diagnostic for measurement of energetic confined {alpha} particles and tritons on the Tokamak Fusion Test Reactor

Journal Article · Sun Sep 01 00:00:00 EDT 1996 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1147419· OSTI ID:391716

Medley, S S; Mansfield, D K; Roquemore, A L ^[1]; Fisher, R K; Duong, H H; McChesney, J M; Parks, P B ^[2]; Petrov, M P; Khudoleev, A V ^[3]; Gorelenkov, N N ^[4]

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1. Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)
2. General Atomics, San Diego, California 92186 (United States)
3. A. F. Ioffe Physical-Technical Institute, St. Petersburg 194021 (Russia)
4. TRINITI, Troisk 142092 (Russia)

Radially resolved energy and density distributions of the confined {alpha} particles in D{endash}T experiments on the Tokamak Fusion Test Reactor (TFTR) are being measured with the pellet charge exchange (PCX) diagnostic. Other energetic ion species can be detected as well, such as tritons produced in D{endash}D plasmas and H, He{sup 3}, or tritium rf-driven minority ion tails. The ablation cloud formed by injected low-{ital Z} impurity pellets provides the neutralization target for this active charge exchange technique. Because the cloud neutralization efficiency is uncertain, the PCX diagnostic is not absolutely calibrated so only relative density profiles are obtained. A mass and energy resolving {ital E}{parallel}{ital B} neutral particle analyzer (NPA) is used which has eight energy channels covering the energy range of 0.3{endash}3.7 MeV for {alpha} particles with energy resolution ranging from 5.8{percent} to 11.3{percent} and a spatial resolution of {approximately}5 cm. The PCX diagnostic views deeply trapped ions in a narrow pitch angle range around a mean value of {ital v}{parallel}/{ital v}={minus}0.048{plus_minus}10{sup {minus}3}. For D{endash}T operation, the NPA was shielded by a polyethylene{endash}lead enclosure providing 100{times} attenuation of ambient {gamma} radiation and 14 MeV neutrons. The PCX diagnostic technique and its application on TFTR are described in detail. {copyright} {ital 1996 American Institute of Physics.}

• Research Organization: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 391716
• Journal Information: Review of Scientific Instruments, Vol. 67, Issue 9; Other Information: PBD: Sep 1996
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION
TFTR TOKAMAK
PLASMA DIAGNOSTICS
ALPHA PARTICLES
TRITONS
CHARGE EXCHANGE
PELLET INJECTION
ION DENSITY
ENERGY SPECTRA
KEV RANGE 100-1000
MEV RANGE 01-10