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Dr. Michael Larson     

Northrop Grumman Aerospace Systems   

"Atomic Frequency Standards"

Ever wonder how an atomic clock works, or why you should care? What is time, and why is it important to measure? In the 1700s the British government decided the problem of accurately and reliably measuring time to aid the navigation of its ships was so important they offered a prize which in today’s money would be >$4 million. Isaac Newton worked on solutions to the problem using celestial observations, but in the end it was a talented clockmaker named John Harrison who developed the most practical solution to the problem and collected more than half the prize money. Clocks have come a long way since then and with every improvement comes new applications with even more demanding requirements for accurate time measurement. This briefing presents the ideas behind, importance of, and techniques for measuring time. Specifically the history behind, general principles of operation, and design for cesium beam clocks will be given. For background a discussion of what time is and its importance in the areas of cell phones and communication networks, power distribution, and navigation will be presented. Also presented will be a short history of the relevance of time to navigation and how that problem inspired John Harrison and a Isaac Newton, or maybe it was the more than $4 million in prize money.

Biography: Dr. Michael Larsen Earned his B.S. from California State University, Fullerton in 2000, and his Ph.D. from the University of Wisconsin, Madison in 2007. In September 2007 he joined the Advanced Technology & Strategic Applications group in the Navigation Systems Division of Northrop Grumman. He is the lead physicist for the DARPA funded Nuclear Magnetic Resonance Gyroscope program and co-principle investigator on the Paramagnetic Magnetometer (PMM) and Magneto-Optical Atom Trap (MOAT) IRAD projects. His research includes work on inertial instruments, electric and magnetic field sensors, and atomic frequency standards.