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Permanent Reactor Physics Jobs (NOW HIRING)

Nuclear Engineer I/II (Reactor Design)

Madison, WI ยท On-site

$99.30K - $118.90K/yr

Knowledge of nuclear physics, neutronics, thermal-hydraulics, and reactor safety principles ... S. citizenship or permanent residency required. What we offer * Competitive salary with equity ...

Knowledgeable of nuclear reactor core physics such as neutron transport theory and reactivity ... Citizen, U.S. Legal Permanent Resident, or of a protected person status Benefits Package:

Knowledgeable of nuclear reactor core physics such as neutron transport theory and reactivity ... Legal Permanent Resident, or a protected person status Benefits Package: Protingent offers ...

Senior Controls Systems Engineer

El Segundo, CA ยท On-site

$158K - $219.45K/yr

The company's first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be ... Experience with permanent magnet synchronous motor control, including FOC, VSM, and sensorless ...

In this role, you will develop high-fidelity CFD models that support reactor design optimization ... S. citizen or lawful permanent resident (green card holder)

Permanent Reactor Physics information

See salary details

$39K

$46.9K

$52.5K

How much do permanent reactor physics jobs pay per year?

As of May 28, 2026, the average yearly pay for permanent reactor physics in the United States is $46,902.00, according to ZipRecruiter salary data. Most workers in this role earn between $43,500.00 and $50,500.00 per year, depending on experience, location, and employer.

Does NASA hire nuclear physicists?

NASA employs nuclear physicists in roles related to space radiation, nuclear propulsion, and energy systems for space missions. These positions often require advanced degrees, security clearances, and expertise in nuclear science and engineering. Nuclear physicists at NASA work on research, development, and safety assessments for space exploration projects.

What is the difference between Permanent Reactor Physics vs Reactor Operations?

AspectPermanent Reactor PhysicsReactor Operations
CredentialsDegree in nuclear engineering or physics, certifications in reactor physicsTraining in reactor operation, certifications like NRC licenses
Work EnvironmentResearch labs, design facilities, regulatory agenciesPower plants, operational control rooms
Industry UsageDesign, safety analysis, researchDay-to-day plant operation, safety monitoring

Permanent Reactor Physics focuses on reactor design, safety analysis, and research, requiring specialized knowledge in physics and engineering. Reactor Operations involves managing the daily functions of running a nuclear reactor, emphasizing operational procedures and safety protocols. Both roles are essential in the nuclear industry but differ in focus and responsibilities.

More about Permanent Reactor Physics jobs
What cities are hiring for Permanent Reactor Physics jobs? Cities with the most Permanent Reactor Physics job openings:
What are the most commonly searched types of Reactor Physics jobs? The most popular types of Reactor Physics jobs are:
What states have the most Permanent Reactor Physics jobs? States with the most job openings for Permanent Reactor Physics jobs include:
Infographic showing various Permanent Reactor Physics job openings in the United States as of May 2026, with employment types broken down into 1% Locum Tenens, 84% Full Time, 14% Part Time, and 1% Nights. Highlights an 97% Physical, and 3% Remote job distribution, with an average salary of $46,902 per year, or $22.5 per hour.

Nuclear Engineer I/II (Reactor Design)

Fissionaire

Madison, WI โ€ข On-site

$99.30K - $118.90K/yr

Full-time

Posted 10 days ago


Job description

As an emerging leader in nuclear engineering, our startup is developing revolutionary reactor technology to secure safe and abundant energy for future generations. ย We are seeking a highly skilled entry-level Nuclear Engineer I/II to join our dynamic team and contribute to the design and development of next-generation nuclear reactors.


Theย Nuclear Engineer I/II will contribute to the design, analysis, and optimization of advanced nuclear reactor systems. The ideal candidate will have a strong background in nuclear engineering, proficiency with industry-standard design software, and a proactive, self-starting attitude. This role requires innovative thinking, technical expertise, and a commitment to advancing safe and sustainable nuclear energy solutions.

Key responsibilities
  • Design and develop nuclear reactor systems, including core design, thermal-hydraulics, and safety systems, ensuring compliance with regulatory standards.
  • Perform simulations and analyses to optimize reactor performance, safety, and efficiency using industry-standard software tools.
  • Collaborate with multidisciplinary teams, including mechanical engineers, materials scientists, and safety analysts, to integrate reactor designs into broader systems.
  • Conduct risk assessments and safety analyses to ensure designs meet stringent nuclear safety requirements.
  • Prepare technical reports, design documentation, and presentations for internal stakeholders and regulatory bodies.
  • Stay updated on advancements in nuclear technology, materials, and regulations to incorporate cutting-edge solutions into designs.
  • Participate in project planning and scheduling to ensure timely delivery of design milestones.
  • Contribute to research and development initiatives for innovative reactor concepts. ย 
qualifications
  • Masterโ€™s degree in Nuclear Engineering or a related field. Ph.D. preferred but not required.
  • Minimum of 1-2 years of experience in nuclear reactor design, analysis, or related fields within industry or in academic work.
  • Proficiency with nuclear design and analysis software, such as MCNP, SCALE, RELAP5, COMSOL, MOOSE, GOTHIC etc.
  • Familiarity with CAD software for reactor component design.
  • Proficiency in programming languages for data analysis, scripting, or automation of design processes.
  • Knowledge of nuclear physics, neutronics, thermal-hydraulics, and reactor safety principles.
  • Experience with Molten Salt Reactor design preferred.
  • Demonstrated ability to work independently, take initiative, and drive projects to completion with minimal supervision.
  • Excellent written and verbal communication skills for technical documentation and cross-functional collaboration.
  • Familiarity with nuclear regulatory frameworks and safety standards.
  • Knowledge of materials science, particularly related to radiation-resistant materials and high-temperature applications.
  • Familiarity with risk assessments and analysis (PRA, FMEA, PIRT etc.) preferred
  • Familiarity with computational fluid dynamics (CFD) for thermal-hydraulic analysis preferred.
  • U.S. citizenship or permanent residency required.
What we offer
  • Competitive salary with equity options
  • Comprehensive benefits, holiday and PTO schedule
  • Opportunity to shape foundational operations in a groundbreaking nuclear startup.

Fissionaireโ€™s technology is subject to U.S. export control regulations, which require the company to review applicantsโ€™ eligibility based on their citizenship or residency status. As part of the application process, candidates will be asked to indicate whether they are a U.S. citizen, green card, lawful permanent resident, asylee, or refugee resident to support this review. Because government authorization timelines can vary, Fissionaire is unable to consider alternate resident statuses where required approvals may not be obtainable within a timeframe that meets business needs.

Fissionaire is an Equal Opportunity Employer that does not discriminate on the basis of actual or perceived race, colour, creed, religion, national origin, ancestry, citizenship status, age, sex or gender (including pregnancy, childbirth, pregnancy-related conditions, and lactation), gender identity or expression (including transgender status), sexual orientation, marital status, family or relationship structure, military service and veteran status, physical or mental disability, genetic information, gender identity, or any other characteristic protected by applicable federal, state, or local laws and ordinances. Fissionaireโ€™s management team is dedicated to this policy with respect to recruitment, hiring, placement, promotion, transfer, training, compensation, benefits, employee activities, access to facilities and programs, and general treatment during employment.

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.