Postdoctoral Research Associate - Nuclear Fallout Modeling

Date: Feb 27, 2024

Location: Oak Ridge, TN, US, 37830

Company: Oak Ridge National Laboratory

Requisition Id 11801 


As a U.S. Department of Energy (DOE) Office of Science national laboratory, ORNL has an extraordinary 80-year history of solving the nation’s biggest problems. We have a dedicated and creative staff of over 6,000 people! Our vision for diversity, equity, inclusion, and accessibility (DEIA) is to cultivate an environment and practices that foster diversity in ideas and in the people across the organization, as well as to ensure ORNL is recognized as a workplace of choice. These elements are critical for enabling the execution of ORNL’s broader mission to accelerate scientific discoveries and their translation into energy, environment, and security solutions for the nation.


We are seeking a Postdoctoral Research Associate who will support the Incident Modeling and Computational Sciences Group in the Nuclear Nonproliferation Division, National Security Sciences Directorate at Oak Ridge National Laboratory (ORNL) with a background in post-detonation nuclear fallout research and with expertise in at least one of the following: hydrodynamic codes, material science, particulate physiochemical characterization, atmospheric physics, or health physics modelling.


Major Duties/Responsibilities: 

  • Conceptualizing and performing research and development of the formation, development, and transport of radioactive debris from urban nuclear explosions.
  • An expertise in one or more of the following areas: nuclear physics, chemistry, mathematical modeling and simulation, and code development.
  • Develop and implement calculational methods for simulation of these nuclear explosion processes and interpreting fallout data.
  • Focus on developing and validating mathematical methods, incorporating inverse calculations and statistical models, and integrating these methods into existing modeling and simulation (M&S) tools.
  • Maintain and develop the codes used for this evaluation, test their performance on different operating systems, and validate results using both numerically generated and actual measured data.
  • Work will usually include a statistical analysis of the uncertainties and correlations in the reconstructed values.
  • Maintain a strong understanding of the overall goals of various federal agencies involved in nonproliferation nuclear forensics missions.
  • Interacting with division staff, both within and outside the Incident Modeling and Computational Sciences group, who work on projects in a team environment.
  • Work independently, perform R&D activities, fully document work in technical reports and publications, effectively interface with project sponsors, and participate in the identification and development of research proposals.
  • Deliver ORNL’s mission by aligning behaviors, priorities, and interactions with our core values of Impact, Integrity, Teamwork, Safety, and Service. Promote diversity, equity, inclusion, and accessibility by fostering a respectful workplace – in how we treat one another, work together, and measure success.


Basic Qualifications:

  • A PhD in nuclear engineering or a related field completed within the last 5 years
  • A firm understanding of the modeling and/or analysis of nuclear fireball physics and chemistry, backed by demonstrated recent and relevant research and development in the field, is a fundamental need for this position.
  • Excellent verbal, presentation, and writing skills are required to enable effective interaction and communication with technical peers, program managers, and sponsors.


Preferred Qualifications:

  • Have recent research and development experience in nuclear fallout and/or nuclear consequence management, with demonstrated accomplishments in the solution of a variety of real-world problems.
  • The candidate should have considerable programming experience using FORTRAN, C++, and/or other high-level languages.
  • Additional capabilities, such as programming on parallel processors using the message-passing interface (MPI) are a plus.
  • It is highly desirable for the candidate to have knowledge and experience with numerical analysis and applied mathematics, including optimization, statistics, and solution of inverse problems.
  • The ideal candidate would also have diverse experience in many application areas such as nuclear forensics, neutron and gamma ray detection, and safeguards technologies.
  • Excellent written and oral communication skills.


Applicants cannot have received their Ph.D. more than five years prior to the date of application and must complete all degree requirements before starting their appointment. The appointment length will be for up to 24 months with the potential for extension. Initial appointments and extensions are subject to performance and the availability of funding.


Please submit three letters of reference when applying to this position. You can upload these directly to your application or have them sent to with the position title and number referenced in the subject line.


Instructions to upload documents to your candidate profile:

  • Login to your account via
  • View Profile
  • Under the My Documents section, select Add a Document

Benefits at ORNL:  

ORNL offers competitive pay and benefits programs to attract and retain talented people. The laboratory offers many employee benefits, including medical and retirement plans and flexible work hours, to help you and your family live happy and healthy. Employee amenities such as on-site fitness, banking, and cafeteria facilities are also provided for convenience.

Other benefits include: Prescription Drug Plan, Dental Plan, Vision Plan, 401(k) Retirement Plan, Life Insurance, Pet Insurance, Generous Vacation and Holidays, Parental Leave, Legal Insurance with Identity Theft Protection, Employee Assistance Plan, Flexible Spending Accounts, Health Savings Accounts, Wellness Programs, Educational Assistance, Relocation Assistance, and Employee Discounts.

If you have difficulty using the online application system or need an accommodation to apply due to a disability, please email:


Special Requirements:


Visa Sponsorship:

Visa sponsorship is not available for this position.


Q clearance: This position requires the ability to obtain and maintain a clearance from the Department of Energy. As such, this position is a Workplace Substance Abuse (WSAP) testing designated position. WSAP positions require passing a pre-placement drug test and participation in an ongoing random drug testing program.



This position will remain open for a minimum of 5 days after which it will close when a qualified candidate is identified and/or hired.

We accept Word (.doc, .docx), Adobe (unsecured .pdf), Rich Text Format (.rtf), and HTML (.htm, .html) up to 5MB in size. Resumes from third party vendors will not be accepted; these resumes will be deleted and the candidates submitted will not be considered for employment.

If you have trouble applying for a position, please email

ORNL is an equal opportunity employer. All qualified applicants, including individuals with disabilities and protected veterans, are encouraged to apply.  UT-Battelle is an E-Verify employer.

Nearest Major Market: Knoxville