Particle reflection and TFTR neutral beam diagnostics

Technical Report · Wed Apr 01 04:00:00 EST 1992

DOI:https://doi.org/10.2172/10140791· OSTI ID:10140791

Kamperschroer, J H; Grisham, L R; Kugel, H W; O`Connor, T E; Newman, R A; Stevenson, T N; von Halle, A; Williams, M D

Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12{degrees}). Beamline calorimeters, of a ``V``-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the ``V``, complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected.

• Research Organization: Princeton Univ., NJ (United States). Plasma Physics Lab.
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 10140791
• Report Number(s): PPPL--2837; ON: DE92013246
• Country of Publication: United States
• Language: English

Related Subjects

440101
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700320
700460
CALORIMETERS
DIAGNOSTIC TECHNIQUES
FUELS
GENERAL DETECTORS OR MONITORS AND RADIOMETRIC INSTRUMENTS
HEATING AND FUELING SYSTEMS
ION SOURCES
NEUTRAL ATOM BEAM INJECTION
PLASMA DIAGNOSTIC TECHNIQUES AND INSTRUMENTATION
POWER
TFTR TOKAMAK