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2027 New Graduate - Nuclear Engineer

Radiant · El Segundo, CA · On-site

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About Radiant

Radiant builds Kaleidos, a portable, factory-built nuclear microreactor that delivers a megawatt of clean power anywhere it is needed. Backed by a16z, Felicis and USV.

About the role

Assist with nuclear design and analysis tasks, including shielding, neutronics, thermal, and fuel-related studies. Support coupled neutronics and thermal calculations to refine system performance models.

What they're looking for

  • BS or MS in Mechanical Engineering, Nuclear Engineering, or a related discipline
  • Graduating in December 2026 or Spring 2027
  • Strong academic foundation in nuclear engineering principles (e.g., reactor physics, thermal-hydraulics, radiation shielding)
  • Proficiency in at least one programming language (Python, C++, C#, or similar)
  • Hands-on experience through coursework, research, projects, or labs in nuclear system design or analysis
  • Familiarity with nuclear simulation codes (e.g., OpenMC, Serpent, MCNP, MOOSE, BISON, RELAP, CFD, Pronghorn, GRIFFIN)
More about this role

Radiant is an El Segundo, CA-based startup building the world’s first mass-produced, portable nuclear microreactors. The company’s first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. Portable nuclear power with rapid-deploy capability can replace similar-sized diesel generators and provide critical asset support for hospitals, data centers, remote sites, and military bases. Radiant’s unique, practical approach to nuclear development leverages modern software engineering to rapidly deliver safe, factory-built microreactors that use existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries beginning in 2028.

Radiant is seeking a highly motivated Nuclear Engineer to join the team.

Assist with nuclear design and analysis tasks, including shielding, neutronics, thermal, and fuel-related studies.

Support coupled neutronics and thermal calculations to refine system performance models.

Document methods, results, and findings in clear technical reports and...

Read the full posting on Radiant's site ↗

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