PPPL: tungsten in plasma can double ignition pressure

Researchers at the DOE's Princeton Plasma Physics Laboratory updated the 70-year-old Lawson criterion with real-world losses, finding that tungsten at one part in 10,000 can roughly double the pressure needed for ignition. The model suggests heating plasma before raising its density as a more energy-efficient route.

• Tungsten at 1 part in 10,000 doubles required ignition pressure
• Model includes helium ash, impurities, synchrotron losses and heat escape
• Proposed route via the Cordey saddle: heat first, then raise density
• Ideal plasma puts the transition at fusion gain Q of about 5