Nuclear Criticality Safety Postdoctoral Research Staff

About the role

We have an opening for a Postdoctoral Researcher with experience in one or more of the following areas: nuclear physics; nuclear engineering; radiation transport; Multiphysics simulation. We are seeking a creative and flexible individuals who meets the scientific requirements and whose skills are aligned with the research mission of the National Nuclear Criticality Safety Program.

This position will require interaction with professional colleagues inside and outside of the Laboratory and is located in the Nuclear Criticality Safety Division within the Environment, Safety and Health Directorate. This position offers a hybrid schedule, blending in-person and virtual presence. The ability to work from home one or more days per week.

You will Collaborate in the design, modeling, and analysis of laboratory critical and subcritical experiments. Collaborate in the development of radiation measurement instrumentation and measurement of radiation fields. Design and oversee fabrication of equipment as required. Develop experimental procedures as required and guide them through safety and management reviews.

Assist in performing criticality safety evaluations of laboratory work. Publish research results in peer-reviewed scientific or technical journals and present results at external conferences, seminars, and/or technical meetings. Perform other duties as assigned.

Qualifications & Requirements

Ability to secure and maintain a U.S. DOE Q-level security clearance which requires U.S. citizenship. PhD in Nuclear Engineering, Physics, or related field. Experience with radiation transport methods, such as MCNP, SCALE, GEANT, COG, Serpent, OpenMC etc. Experience in computational physics and working knowledge of one or more programming languages (Python, FORTRAN, C++, etc).

Demonstrated proficient verbal and written communication skills necessary to author technical and scientific reports, proposals, publications and deliver scientific presentations. Ability to work independently as well as in multidisciplinary research teams. Ability to provide in-depth analyses and develop unique technical solutions.

Pay and benefits

We Desire Active DOE Q clearance. Pay Range $135,768 Annually This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting; pay will not be below any applicable local minimum wage. An employee's position within the salary range will be based on several factors including, but not limited to, specific competencies, relevant education, qualifications, certifications, experience, skills, seniority, geographic location, performance, and business or organizational needs.

Additional Information

#LI-Onsite Position Information This is a Postdoctoral appointment with the possibility of extension to a maximum of three years, open to those who have been awarded a PhD at time of hire date. Why Lawrence Livermore National Laboratory? Included in 2026 Best Places to Work by Glassdoor!

If you are selected, we will initiate a Federal background investigation to determine if you meet eligibility requirements for access to classified information or matter. Also, all L or Q cleared employees are subject to random drug testing. Q-level clearance requires U.S. citizenship. Pre-Employment Drug Test External applicant(s) selected for this position must pass a post-offer, pre-employment drug test.

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