Nuclear Engineer, Diagnostics

About Helion

We are a fusion power company based in Everett, WA, with the mission to build the world's first fusion power plant, enabling a future with unlimited clean electricity. Our vision is a world with clean, reliable, and affordable energy for everyone. 

Since Helion's founding in 2013, we have raised over $600 million from investors such as Sam Altman, Mithril, and Capricorn Investment Group to propel us forward. Our last prototype, Trenta, completed 10,000 high-power pulses and reached plasma temperatures of 100 million degrees Celsius (9 keV). 

Now we are working toward Polaris, which will be the first machine to demonstrate electricity from fusion, making this a great time to join Helion! Bring your skills, experiences, and determination to make a difference in the world. Together, we can make a future with unlimited clean electricity from fusion a reality.  

What You Will Be Doing:

We are seeking a Nuclear Engineer to develop, operate, and analyze data from advanced diagnostic detectors for Polaris and future fusion generators. This role involves designing, building, integrating, and optimizing diagnostic systems for accurate measurements and supporting the nuclear diagnostics needs of Helion Energy. You will perform signal processing, yield mapping, and analysis to improve signal-to-noise ratios at diagnostic ports. You will complete design reviews, communicate results, and document all aspects of diagnostics. In this collaborative role, you will interface with many other teams including Mechanical Engineering, Plasma Physics, and Test Operations. This position offers a unique opportunity to contribute to cutting-edge fusion energy development through innovative diagnostics and nuclear engineering expertise. This is an onsite role, and you will report to the Nuclear Engineering Manager.

You Will:

• Design, construct, calibrate, and operate diagnostics for neutrons, photons, and charged particles using various detector types, including organic scintillators, inorganic scintillators, semiconductor detectors, ion chambers, and activation foils
• Develop scripts in MATLAB or Python to process detector outputs, generate plots, and perform data analyses for internal presentations to the RaSNS, Research (Plasma Physics), and Test Operations teams, as well as external presentations at technical conferences
• Conduct uncertainty quantification and error propagation to ensure the reliability and accuracy of diagnostic results
• Apply complementary skills to advance detector development, such as Monte Carlo simulations or circuit and electrical design

Required Skills:

• Strong understanding of nuclear physics, including neutron and photon interactions, cross-sections, attenuation, radioactive decay, and various radiation types
• 3 years of experience designing, constructing, operating, and analyzing detectors. Experience should include tasks such as electronic readout design, coupling scintillators to readout electronics, digitizers, high-voltage supplies, and data acquisition systems (DAQ)
• 3 years of experience in data analysis, including processing raw pulses (e.g., pile-up rejection and pulse shape discrimination) and performing uncertainty quantification and propagation
• Proven experience documenting detector designs, operational methodologies, and analysis scripts for reproducibility and knowledge sharing

Preferred Skills:

• Proficiency in designing and developing circuitry and electronics for diagnostic detectors
• Familiarity with MCNP6, including the ability to obtain a license and effectively use the software for simulation and analysis
• Experience working in environments with pulsed electromagnetic fields and managing large EMI noise challenges

#LI-Onsite #LI-KL1

Compensation and Benefits

At Helion, we are committed to fostering a fair and equitable environment in every aspect of our operations, including compensation. We ensure all our roles are competitively benchmarked and our total compensation package includes a base salary, comprehensive benefits, and equity grants, giving you a true stake in Helion's success. Final compensation is determined through a holistic evaluation of your experience, qualifications, and our commitment to maintaining internal equity, ensuring fairness and transparency across our teams.

This is an exempt salaried role.

Annual Base Pay$128,000—$160,000 USD

Benefits

Our total compensation package includes benefits, including but not limit