Senior Neutronics Engineer

We have an opening for a Senior Neutronics Engineer to support projects within the National Ignition Facility & Photon Sciences (NIF&PS) / Extreme Light Matter and Fusion (LMF) directorate home to the National Ignition Facility (NIF) the worlds most energetic this role you will work with the Radiation and Mutli-Physics Analysis Group as well as other LLNL organizations to perform complex radiation transport simulations of radiation environments in the NIF as well as other facilities. You will have advanced knowledge of radiation measurement techniques and work on characterizing the radiation field during NIF shots. You will work with LLNL team members to expand understanding of radiation effect on diagnostics electronics and other materials. This position is in the Laser Systems Engineering & Operations (LSEO) Division of the Engineering Directorate.

Depending on your assignment this position may offer a hybrid schedule blending in-person and virtual presence. You may have the flexibility to work from home one or more days per week. 

In this role you will

• Operate under consultative direction with substantial authority using in-depth analysis and subject matter expertise in highly advanced concepts to resolve a diverse range of highly complex problems independently determine strategies modify approaches and pursue actions that impact organizational operations or directions and achieve long-term goals.
• Perform radiation transport simulations to identify radiological hazards and identify potential shielding solutions.
• Perform detailed activation analyses and characterize decay dose rate environment.
• Apply radiation transport methods to predict potential damage to electronics due to total ionizing dose displacement damage and single event effects.
• Characterize neutron sources and radiation fields affecting diagnostic systems.
• Develop and optimize computational tools for coupling neutronics and activation analyses.
• Support neutronics analysis activities in collaboration with the Livermore Institute of Fusion Technology (LIFT).
• Prepare supporting safety and engineering documentation for complex analyses and safety base.
• Lead and contribute to proposals for new work applying appropriate estimating techniques.
• Participate in professional committees conferences or working groups with other laboratories and/or government agencies and customers to develop business strategies and programs.
• Prepare and present briefings to internal or external customers.
• Maintain current knowledge of applicable regulatory Safety Standards and Emerging Modeling Tools.
• Perform other duties as assigned.

Qualifications :

• Ability to obtain and maintain a U.S. DOE Q-level security clearance which requires U.S. citizenship.
• Bachelors degree in Nuclear Engineering or related technical field or the equivalent combination of education and previous relevant experience.
• Extensive experience developing and applying radiation transport codes such as MCNP Open MC SCALE Shift Attila Denovo and ADVANTG.
• Expert level application and experience developing and applying activation codes such as FISPACT ALARA CINDER and ORIGIN.
• Expert level experience applying CAD to Monte Carlo radiation transport codes using conversion tools such as GEONUED McCAD and DAGMC.
• Highly advanced knowledge of and significant experience with current state-of-the-art neutronics tool development.
• Expert knowledge of and significant experience with radiation shielding for experimental facilities.
• Expert knowledge of and significant experience in simulating post-irradiation environment in experimental facilities.
• Expert knowledge of radiation measurement techniques.
• Expert communication facilitation and collaboration skills necessary to prepare present and explain highly complex reports and effectively deliver highly advanced technical presentations as well as influence and advise senior management and/or external sponsors.

Qualifications We Desire

• PhD degree in Nuclear Engineering or related technical field or the equivalent combination of education and previous relevant experience.
• Significant experience in shielding design and simulation of post-irradiation environment to meet radiological protection goals in experimental facilities.
• Experience with shielding design to allow for survivability of vulnerable electronics and other equipment in high radiation environments.
• Experience with utilizing hybrid deterministic/Monte Carlo neutronics modeling.
• Experience with developing novel approaches to predict radiation backgrounds in high radiation environments.
• Experience with neutronics and activation analyses for magnetic and inertial fusion facilities and/or fusion power plant studies.
• Experience with applying sensitivity and uncertainty methods using tools such as ASUSD and SUSD3D to quantify nuclear data and modeling uncertainties.
• Experience with performing verification and validation using operating data and shielding benchmark studies.
• Experience in leading projects and managing project schedules.
• Knowledgeable about Monte Carlo radiation transport using GPU architectures.

Pay Range

$210630 - $267030 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.  An employees 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-Hybrid

Position Information

This is a Career Indefinite position open to Lab employees and external candidates.

Why Lawrence Livermore National Laboratory

• Included in 2026 Best Places to Work by Glassdoor!
• Flexible Benefits Package
• 401(k)
• Relocation Assistance
• Education Reimbursement Program
• Flexible schedules (*depending on project needs)
• Our values - visit  Clearance

  This position requires a Department of Energy (DOE) Q-level clearance.  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. 

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  Remote Work :

  No

  
  

  Employment Type :

  Full-time