BASIC REQUIREMENTS: Degree: physics; or related degree that included at least 24 semester hours in physics; OR Combination of education and experience -- courses equivalent to a major in physics totaling at least 24 semester hours, plus appropriate experience or additional education. In either 1 or 2 above, the courses must have included a fundamental course in general physics and, in addition, courses in any two of the following: electricity and magnetism, heat, light, mechanics, modern physics, and sound. ADDITIONAL REQUIREMENTS: In addition to the basic requirements above, applicants must possess one year (52 weeks) of specialized experience equivalent to at least the GS-12 level (ZP-III at NIST.) Specialized experience is defined as: experience with the development of optical lattice clocks, including evaluation of systematic uncertainties of optical clocks and laser cooling of alkaline earth elements. Experience refers to paid and unpaid experience, including volunteer work done through National Service programs (e.g., Peace Corps, AmeriCorps) and other organizations (e.g., professional; philanthropic; religious; spiritual; community, student, social). Volunteer work helps build critical competencies, knowledge, and skills and can provide valuable training and experience that translates directly to paid employment. You will receive credit for all qualifying experience, including volunteer experience. The qualification requirements in this vacancy announcement are based on the U.S. Office of Personnel Management (OPM) Qualification Standards Handbook. If requesting reconsideration of your qualification determination, please refer to the following site: Applicant Reconsideration