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Radiant is building the world's first mass-produced, portable nuclear microreactors. The company's flagship product, Kaleidos, is a 1-megawatt, fail-safe microreactor designed for rapid deployment to hospitals, data centers, remote sites, and military bases. Founded in 2020 and headquartered in El Segundo, CA, Radiant is preparing to test its first reactor at Idaho National Laboratory this summer, with customer deliveries expected in 2028.
As a Nuclear Engineer focused on Sensors and Instrumentation, you will own the design, analysis, and qualification of sensor and instrumentation solutions for the Kaleidos microreactor. This role encompasses radiation detection systems (fission chambers, ion chambers), neutron flux monitoring, and instrumentation design for reactor physics, shielding, and safety applications.
Key responsibilities include:
- Design, specify, and qualify in-core and ex-core detector systems for neutron flux and radiation monitoring
- Support detector response modeling using radiation transport codes (MCNP, OpenMC, Serpent) to verify performance requirements
- Evaluate sensor survivability and performance under high-temperature, high-radiation, and accident-condition environments
- Partner with reactor control and data acquisition engineers to integrate sensor outputs into monitoring, protection, and control systems
- Lead verification and validation of instrumentation against customer and regulatory requirements
- Provide technical expertise and feedback to cross-functional engineering teams
Required qualifications include a bachelor's degree in nuclear engineering, 1–2+ years of nuclear industry experience with exposure to radiation detection or instrumentation, proficiency with radiation transport methods, competency in scientific computing languages (Python, C++, C#, FORTRAN), basic thermal hydraulics knowledge, and strong communication skills.
Desired qualifications include hands-on sensor/instrumentation design and testing in harsh environments, data acquisition systems experience, familiarity with variance reduction techniques, CAD proficiency, dose consequence modeling knowledge, and hardware design or testing experience.
The role requires 100% onsite presence at El Segundo headquarters and willingness to work extended hours as needed. Radiant offers substantial equity grants, comprehensive health benefits (medical, vision, dental), 8 weeks paid parental leave, catered daily lunch, flexible PTO, and a collaborative startup environment near the Pacific Ocean.
