Radiation Shielding Engineer

About Us At Antares, our long-term mission is to make clean energy abundant from Earth to the Asteroid Belt. We’re fueled by the belief that advanced nuclear energy can strengthen our military, solve the climate crisis, elevate global living standards, and expand humanity's presence in outer space. To achieve our mission, we’re building mass-producible, inherently safe, deployable microreactors that can be used terrestrially, underwater, and in space. Formed in 2023, the Antares team hails from SpaceX, The White House, MIT, Rigetti Computing, The Air Force, General Atomics, Relativity Space, Ursa Major, and National Laboratories like Los Alamos, Idaho, and Oak Ridge. Antares has raised over $130M in venture capital from top-tier investors and has over $13M in government funding. About the Role As a member of the Licensing and Safety Analysis team, you will be the responsible engineer for the characterization of radiation sources as well as the design and analysis of radiation shielding for reactor operation, shutdown conditions, as well as post operation transportation, storage, and disposition. You will apply best available analysis tools to characterize radiation sources from fission, activation, and decay. You will work as an integral member of the reactor and site design team to design and analyze the best available shielding configuration to meet customer requirements for a variety of deployment scenarios. The ideal candidate has a mix of industry and academic experience and has worked in a team-oriented environment to develop nuclear technologies for real-world applications. While you may have an area of expertise, you’re not afraid to operate as a generalist in a growing organization. Roles and Responsibilities: You will develop and provide expertise in a subset of the following: Ownership of radiation shielding design and analysis Development of trade studies of materials choices Development of neutronics simulations to characterize radiation sources during operation and in post-operation configurations Optimization of radiation shielding for deployment and post-operation transportation. Engagement in regulatory requirement compliance strategies and application to licensing pathways. Ensuring utilized tools and analyses are established and maintained in comliance with Antares quality assurance program. Basic Qualifications: Bachelor’s degree in nuclear or mechanical engineering, physics, material science, or related field 3+ experience with radiation shielding analysis and design Proficiency in modern radiation shielding analysis tools, such as MCNP/ADVANTG, SCALE/MAVRIC, or similar Monte Carlo variance reduction tools Ability to navigate regulatory requirements, shielding design features, analysis tools and manufacturing methods. Preferred Skills & Experience: Strong interpersonal and collaborative skills, enthusiasm for problem solving, and desire to modernize nuclear design and operation Master's degree or PhD in nuclear engineering Demonstrated track record of high impact in the achievement of team goals Strong project management skills and effective communication of technical concepts across multi-disciplinary teams Broad knowledge of nuclear interactions with material selections, especially for radiation shielding applications Working knowledge of a programming language, preferably Python Additional Requirements: Ability to work long hours and weekends as necessary to support critical milestones Ability to travel to regulatory locations as needed Location We are located in Torrance, CA in a 322,000 square foot, brand new facility featuring large open spaces for team collaboration, R&D, and production, as well as easy access to the 405, 105, and 110 freeways. Our facility is in the heart of Los Angeles' vibrant emerging tech ecosystem alongside many other high growth startups and enterprises. Culture At Antares, we like to specifically tie each role to our founding document’s set of values–here are the top five cultural values we think you should believe at your core to be successful: Think in Systems - Energy and Defense are complex ecosystems with numerous stakeholders with competing priorities, conflicting policies, perverse incentives, and emergent and path-dependent properties. First principles thinking alone is insufficient. Think probabilistically and then take action. “If you want to be certain, then you are apt to be obsolete.” Over-optimizing the components often degrades the system Obsess over the End User - The customer and end user are often not the same. We will never build globally competitive commercial products if we lose sight of our end users and their entire interaction with the product life cycle Be Unconstrained by Convention - Our only limits are the laws of physics. Many, even experts, will say what we are working on is impossible. They said the same about SpaceX reusing rockets. Generationally impactful companies, by definition, must accomplish the seemingly impossible. If it were easy, it would have already been done. Never shy away from a solution because it has never been tried before, and never choose to do something because that's “how it's always been done” Go Where the Work I s - Never miss a chance to meet a customer, user, or stakeholder face to face, even if that means hopping on a plane. If you can’t make it, find a teammate who can channel your intentions and go in your place. Deep work can be done from anywhere, but we believe teams are built in person, and aim to maximize our time together Operate in the Grey - Embrace nuance in pursuit of truth. Question every fundamental assumption Equal Opportunity Antares is an Equal Opportunity Employer. Employment decisions are based solely on merit, competence, and qualifications, without regard to race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability, or any other legally protected status. ITAR Requirements To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here .

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