Scientist V

General Atomics (GA), and its affiliated companies, is one of the world’s leading resources for high-technology systems development ranging from the nuclear fuel cycle to remotely piloted aircraft, airborne sensors, and advanced electric, electronic, wireless and laser technologies.

Under general supervision with limited review, this position is responsible for determining and developing effective approaches for resolving a wide range of difficult scientific problems in plasma‑materials interactions (PMI) for magnetic fusion energy. Assignments are normally outlined in terms of overall objectives and anticipated results. The scientist will document findings, communicate results to scientific staff, and make technical presentations as required. The scientist may coordinate segments of a specific project. The scientist may provide direction to design or technical staff and may provide direction to less experienced professional staff.

This position performs PMI research within the Comprehensive Investigation of Tokamak Impurities and Understanding of Surfaces (CITIUS) program, managed by General Atomics on behalf of the U.S. Department of Energy. The scientist will lead experimental and/or modeling efforts focused on plasma‑facing material survivability and tungsten impurity source modeling in tokamak environments, with emphasis on one or more of the following topics:

• Stress-testing advanced tungsten alloys and composites
• Evaluation of re-deposited tungsten layers and slag‑like deposits
• Spectroscopic inference of net tungsten erosion
• Preferential sputtering and surface evolution of tungsten alloys

The scientist will collaborate closely with materials scientists, computational modelers, and experimental plasma physicists across the CITIUS team and external institutions.

DUTIES AND RESPONSIBILITIES: 

The scientist will perform one or more of the following essential functions:

• Plan, execute, and analyze DIII‑D DiMES and, where applicable, tile‑scale experiments to evaluate advanced materials under divertor‑relevant heat and particle fluxes.
• Coordinate fabrication, qualification, and exposure of tungsten‑based materials (e.g., additively manufactured W, dispersion‑strengthened W, W heavy alloys, Wf/W composites) to assess thermal shock resistance, crack formation thresholds, net erosion, surface morphology evolution, and hydrogenic fuel retention.
• Design and interpret experiments on re-deposited tungsten layers and mixed material deposits to quantify gross and net erosion, effective sputtering yields, and dust/slag production using in‑situ spectroscopy, imaging diagnostics, and post‑mortem analysis.
• Lead DiMES experiments that correlate W-I/W-II/W-III line emission with net tungsten erosion, including during ELMs and inter‑ELM phases, and integrate spectroscopic data with RBS/NRA and other post‑mortem measurements to derive validated relationships between emission and net erosion.
• Implement and apply homogeneous mixing models (HMM) and related PMI tools (e.g., RustBCA, ERO2.0) to predict preferential sputtering, surface composition evolution, and effective erosion of tungsten alloys and heavy alloys for divertor and main‑chamber‑relevant conditions.
• Coordinate with collaborators for pre‑ and post‑exposure characterization and incorporate these results into PMI and impurity source models.
• Prepare technical reports and presentations summarizing methods, results, and impacts; contribute to peer‑reviewed publications; and present results at scientific meetings.
• Stay informed about advances in fusion materials science, PMI diagnostics, and impurity modeling, and propose improvements to experimental protocols, diagnostics, and modeling workflows.
• Perform other duties as assigned or required.

We recognize and appreciate the value and contributions of individuals with diverse backgrounds and experiences and welcome all qualified individuals to apply.