Brian LaBombard is a 🏷️#physicist and Senior Research Scientist at the 📝MIT Plasma Science and Fusion Center, where his field is boundary and 📝divertor plasma physics — the few centimeters of 📝scrape-off layer that decide how much power reaches a tokamak's walls. He joined 📝Alcator C-Mod in 1988, at the start of its construction, contributed to the design and installation of its molybdenum 📝first wall and its vertical target plate divertor, and built the machine's edge diagnostics: scanning 📝Langmuir probe systems, embedded probe arrays, divertor pressure gauges and an in-situ ion mass spectrometer. He is a Fellow of the American Physical Society.

Those instruments produced measurements rather than projections, and on C-Mod they produced several the field still uses. LaBombard identified main-chamber recycling — 📝plasma reaching the main wall instead of the divertor — and traced it to intermittent, non-diffusive cross-field transport in the scrape-off layer; he tied the collisionality scaling of that transport to the empirical density limit described by the 📝Greenwald limit; and he showed that ballooning-like transport asymmetries drive near-sonic parallel flows that impose a 📝plasma rotation boundary condition on the confined plasma. He invented the Mirror Langmuir Probe to resolve edge turbulence at the timescale on which it actually occurs. In the 2015 ADX proposal (Nuclear Fusion 55, 053020) he set out the X-point target divertor: a long-legged geometry that runs exhaust down an extended channel past a secondary 📝X-point before it reaches a target. The 2018 ARC exhaust design study led by 📝Adam Kuang, on which he is a co-author, adopted a long-legged divertor for 📝ARC — a modeled projection for a machine not yet built.