Carlos Paz-Soldan is a 🏷️#physicist, associate professor of applied physics and applied mathematics at Columbia University, and founding director of the 📝Columbia Fusion Research Center, which launched in April 2025. His subject is the transient off-normal event — the 📝disruption, the 📝runaway electrons beam it can leave behind, and the actuators that might stop either. He joined Columbia in 2021 from 📝General Atomics, where he was a scientist in the Magnetic Fusion Energy Division working on the 📝DIII-D National Fusion Facility. He earned his Ph.D. at the University of Wisconsin–Madison in 2012 and was elected a Fellow of the American Physical Society in 2024.

His runaway electron work is experimental and was done on operating machines. Measurements on DIII-D resolved how a runaway population's momentum distribution evolves in space and time (Physical Review Letters 118, 255002, 2017) and validated model predictions against DIII-D data (Nuclear Fusion 59, 066025, 2019). Experiments on DIII-D and 📝JET then showed that secondary 📝deuterium injection drives the beam into a large-scale current-driven instability that terminates it benignly — at JET, megaampere-level runaway currents were ended without measurable first-wall heating (doi:10.1088/1741-4326/ac2a69). He is a co-author on the 2022 study extending the 📝runaway electron mitigation coil concept across 📝SPARC and DIII-D (doi:10.1088/1741-4326/ac83d8); that work is simulation, and no passive 3D coil has been tested in a disruption on any machine. He also co-authored the 2026 📝magnetohydrodynamics stability analysis of 📝ARC led by 📝Nils Leuthold (doi:10.1017/S0022377826101421), published under Columbia authorship at an institution holding sponsored research agreements with more than ten private 📝fusion companies at once, and with 📝Dennis Whyte and Brian Wirth the 2023 Physics of Plasmas paper on the academic research ecosystem fusion energy development requires (doi:10.1063/5.0167369).