Energy confinement time (τ_E)

How long the plasma retains its energy (τ_E): the energy stored in the plasma divided by the rate at which it loses energy, which equals the heating power only when the plasma is steady. This is NOT the length of the discharge. A machine can hold a plasma for 1,000 seconds with a confinement time of a fraction of a second, and conflating the two is one of the most common errors in coverage. Operators also differ in whether they correct for the plasma's stored energy still rising, so two confinement times for similar plasmas can differ by definition alone.

Vocabulary id: metric:energy-confinement-time
Scheme: Metrics
Records using it: 22

Measured on 22

JT-60U T-3 ST TFR PLT Alcator A Alcator C ASDEX Joint European Torus Tokamak Fusion Test Reactor DIII-D START MAST NSTX Experimental Advanced Superconducting Tokamak KSTAR C-Mod ASDEX UPGRADE GLOBUS-M2 ST40 SPARC ITER

See the benchmark for the values, each with its status and source.

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Energy confinement time (τE)

Measured on 22

Energy confinement time (τ_E)