Yijun Lin is a 🏷️#physicist specializing in radio-frequency heating at the 📝MIT Plasma Science and Fusion Center, and lead author of "Physics basis for the ICRF system of the SPARC tokamak" (2020) — the design case for the only external heating 📝SPARC will have.

That constraint is unusual. Most large tokamaks combine 📝neutral beam injection with several 📝RF heating methods; SPARC is compact enough that beams do not fit, so 📝ion cyclotron resonance heating carries the whole auxiliary load for both full-field 📝deuterium–📝tritium operation near 12 📝tesla and reduced-field 📝D-D operation near 8. Lin's paper works the problem from the antenna outward: a fast wave near 120 megahertz, an antenna spectrum of roughly 15–18 per meter chosen to balance core absorption against edge coupling, straps rotated about ten degrees to sit perpendicular to the field so they sputter fewer impurities into the plasma, and a final layout of twelve four-strap antennas across six ports, mounted on the inner wall with three-strap port-plug antennas held as a backup against failure during the tritium campaign. Antenna loading was assessed by comparison against 📝Alcator C-Mod, the machine on which much of this expertise was built. The design is validated by modeling and by C-Mod experience, not yet by SPARC operation.