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STS Neutronics Scientist

Date: Jan 18, 2023

Location: Oak Ridge, TN, US, 37830

Company: Oak Ridge National Laboratory

Requisition Id 9741 


Oak Ridge National Laboratory (ORNL) is seeking a Neutronics Scientist for the Second Target Station (STS) project. The STS is a >$1Billion, Department of Energy project to be constructed at the ORNL Spallation Neutron Source (SNS).  The STS will provide new capabilities for the study of a broad range of materials with neutron scattering and support thousands of users from the physical, materials, and applied sciences and industry. The science capabilities provided by the instrument suite at the STS will complement those of the two existing DOE Office of Science neutron scattering user facilities at ORNL, the First Target Station (FTS) of the SNS and the High Flux Isotope Reactor (HFIR). The STS will deliver the highest peak brightness of cold neutrons in the world, which together with advances in neutron optics, instrumentation, and detectors, will ensure US leadership in neutron scattering for decades to come.


The STS Neutronics group is responsible to perform all neutronics analyses necessary the design of the Second Target Station. This includes but is not limited to the support of the Target Systems, Accelerator Systems and Instrument Systems.



The Neutronics Scientist performs simulations of complex nuclear systems with state-of-the-art radiation transport codes, contributes to the development and maintenance of nuclear analysis tools to support complex analysis needs, and develops shielding design solutions towards providing a safe environment to users of the facility. The Neutronics Scientist will participate in experimental programs towards beam characterization and moderator development.  The Neutronics Scientist will work closely with STS design engineers and scientists to optimize the STS configuration.

Major Duties and Responsibilities:

  • The selected applicant will contribute to the design, installation, and commissioning of STS by performing relevant neutronics analyses providing results of interest such as moderator neutron performance, radiation-induced material damage estimates, nuclear heating, activation, etc., while working in an interdisciplinary team of scientists, engineers, and designers.
  • Utilize expertise towards the design and modeling of shielding solutions for proton accelerator, target/moderator systems, and neutron scattering instruments.
  • Develop and implement strategies to optimize the utilization of neutrons from the source to the neutron scattering instruments in collaboration with instrument development teams.
  • Contribute to the development and maintenance of nuclear analysis tools to support complex analysis needs.
  • Develop external collaborations with other institutions developing similar or complimentary techniques.
  • Document and publish results of neutronics development, design, and/or analysis.
  • Ensure and monitor compliance with environment, safety, health (ESH), and quality program (QA) requirements. Promptly identify ESH and QA issues and communicate them to project and division management, ESH and QA contacts, and/or subcontractor contacts as appropriate.
  • As a member of the ORNL scientific community, neutron scientist will be expected to commit to ORNL's Research Code of Conduct.  ORNL’s full code of conduct, and a statement by the Lab Director's office can be found here:


Basic Qualifications:

  • Ph.D. in nuclear engineering or physics, with degree focus on neutron scattering, neutron source development, or radiation transport simulations
  •  At least 2 years of relevant experience in neutronics analysis after Ph.D.
  • Ability to articulate analysis results orally and in writing to colleagues that may or may not be neutronics experts
  • Ability to understand and balance engineering constraints against neutronics and physics figures of merit
  • Experience in utilization and development of Monte Carlo techniques for particle transport
  • Programming experience in computer languages such as C, Fortran, Perl, and Python
  • Demonstrated success in working with a multi-disciplinary team in a dynamic research environment
  • A strong record of scientific publication
  • Excellent oral and written communication skills
  • Must be available for some domestic and international travel
  • This position requires access to technology that is subject to export control requirements.  Successful candidates must be qualified for obtaining licenses for export-controlled codes and libraries (including source codes) distributed by RSICC, such as, but not limited to, the MCNP6.


Preferred Qualifications:

  • Prior experience in the neutronics design and analysis of spallation targets
  • Experience in the use of Monte Carlo particle transport simulation techniques for spallation physics
  • Experience with neutron detectors, data acquisition systems, cryogenics


Other Requirements:

Please provide a list of publications when applying for this position. 


Work Direction and Interface:

Position reports to the STS Neutronics Group Leader. 


Authority/Approval Levels:   Independently performs complex neutronics analysis and design tasks in cooperation with other neutronics scientists, engineers, and designers


Measures of Effectiveness:

  • Successfully contributes to design of STS systems components via neutronics analysis
  • Successfully communicates the analysis results and design recommendations verbally and in writing
  • Successfully represents STS at reviews and other project meetings and workshops


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.

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