Tom Looby is a 🏷️#physicist whose plasma-boundary work is published under a 📝Commonwealth Fusion Systems affiliation. He is the author of HEAT — the Heat Flux Engineering Analysis Toolkit, published in Fusion Science and Technology in 2022 with 📝Matt Reinke among the co-authors — which traces magnetic field lines from the 📝scrape-off layer onto three-dimensional CAD geometry to predict where a tokamak's exhaust power lands on its 📝plasma-facing components, and is a co-author of "Power and particle exhaust for the ARC fusion power plant" (2026) with 📝Thomas Eich.

HEAT's credibility rests on a measurement made elsewhere. In 2025 two of its physics modules — the optical heat flux approximation and photon volume emission — were validated against 📝ASDEX Upgrade data, comparing infrared heat flux profiles and thermocouple temperatures from two tiles, one on the outer 📝divertor target crossed by the strike line and one in the private flux region exposed only to radiation, across 📝L-mode, Type-I ELMy 📝H-mode and quasi-continuous-exhaust H-mode pulses. The L-mode case matched cleanly; the ELMy case did not, because those runs did not model 📝edge localized modes, and the quasi-continuous-exhaust case pointed to a broadened power fall-off length from filamentary transport. Those are ASDEX Upgrade's numbers. Turned on 📝SPARC and 📝ARC — for exhaust design and for thermal modeling of 📝runaway electron damage — the same code produces projections for machines not yet operating. Looby worked at 📝Oak Ridge National Laboratory from 2018 to 2022 and holds a doctorate from the 📝University of Tennessee, Knoxville.