Measurement conventions

Important Nominal Dimensions

• HFS limiter R0: 14 cm (~5.5")
• LFS limiter R0: 65 cm (~25.5" according to CAD drawing) (projected from shell edge)
• Shell Groove R0: 66 cm (~26.0" according to CAD drawing) (projected from shell edge)
• Shell Back R0: 67.2 cm (~26.45" according to CAD drawing)
• Center stack outer radius: 10 cm (4")
• Vessel wall inner radius: 70 cm (~27.5")
• Plasma axis Z: 0 cm
• Lower shell limiter Z: -36 cm
• Vessel top Z (inner): +45 cm (+17.69")
• Vessel bottom Z: -45 cm (-17.69")
• Shell Surface Area: ~4 m2 (VERIFY)
• Shell Enclosed Volume: ~1 m3 (VERIFY)
• Toroidal Segment Angle: 22.5 deg.

Nominal parameters (as of July 2019)

• Shell geometric/nominal major radius R₀: 40 cm
• Shell geometric/nominal minor radius a: 26 cm
• Typical Equilibrium major radius R₀: 34 cm (VERIFY)
• Typical Equilibrium minor radius a: 20 cm (VERIFY)
• Maximum on axis toroidal field B_T: 0.3 T
• LTX Maximum on axis toroidal field B_T: 0.17 T
• Maximum plasma current I_p: ~100 kA
• LTX Maximum plasma current I_p: ~80 kA (~85 kA with deuterium)
• Maximum density: ~10 μm-3 (VERIFY)
• Maximum shot duration: ~50 ms (VERIFY)
• Maximum NBI injected power: >500 kW
• Maximum NBI voltage: >18 kV
• Maximum NBI extracted current: >40 A (VERIFY)
• Maximum NBI neutralized current: >33 A (VERIFY)
• Minimum NBI shine through: 40%
• Maximum NBI duration: 5-6 ms
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• :

Nominal projected parameters

• Maximum projected on axis toroidal field B_T: 0.35 T
• Maximum projected plasma current I_p: >125 kA
• Maximum projected NBI injected power: 700 kW
• Maximum projected NBI voltage: 20-23 kV
• Maximum projected NBI extracted current: >40 A (VERIFY)
• Maximum projected NBI neutralized current: 35 A (VERIFY)
• Maximum projected NBI duration: 30 ms (with new supply)

Position and Sign Conventions

• Toroidal zero angle (φ=0): Center of P-A gap (interferometer port)
• Toroidal positive direction (+φ): Right-handed (i.e. counter-clockwise from above)
• Poloidal zero angle (θ=0): HFS midplane
• Poloidal positive direction (θ=0): Left-handed (i.e. down on HFS)
• Magnetic sensor polarity
  • Vertical field sensor +B: +Z
  • Poloidal field sensor +B: +θ
  • Toroidal field sensor +B: +φ

Currents, Fields, and Flows

• Plasma current (IP): -φ
• Poloidal field from plasma current (BP): +θ
• Ohmic heating flux (BOH): +Z
• OH current (IOH): +φ
• Vertical field (BVF): +Z
• PF coil "positive" current (Icoil): +φ
• Toroidal field (BTF): +φ (since Aug. 29th 2013)
  • Electron curvature drift direction in TF (vRxB): -Z
• TF current (ITF): -θ (since Aug. 29th 2013)

Units

• Density: μm-3
• Perveance: statPervs (A / kV^1.5)