Physics colloquium-“Inverse Midas Effect: Using Nuclear Physics to Explain a Mysterious Failure & Assess the Severity of a New Radiation Threat”

Raymond Ladbury

NASA

Abstract: Watching a part fail while radiation testing is not an uncommon experience.  However, when the previous testing on your part suggests that protons are too feebly ionizing to kill your part and it dies anyway…that will make you sit up and take notice!  And when your billion-dollar satellite is already flying these same parts in a proton-rich portion of space, it will make your management take notice!  The path to an answer is lined with gold, but in this case, the gold nuclei fission—an inverse Midas Effect, with the daughter ions bombarding the electronics and causing unanticipated failures.  And once the mechanism is known, the real work begins as every mission at NASA strives to answer the question—is my satellite vulnerable to the same failures?  Follow a tale of gold fever, bringing together topics from astrophysics to nuclear physics to exotic microelectronic failure modes to answer the question: How deep are we into the soup, and what can we do about it?

Biography: Dr. Ray Ladbury has served as a radiation physicist in the Radiation Effects and Analysis Group (REAG) at NASA Goddard Space Flight Center since January, 2000. He has served as lead radiation engineer for many NASA programs and missions, including the James Webb Space Telescope, SWIFT, LANDSAT8, OSIRIS-REx and the GOES and TDRS programs. Within the REAG, Dr. Ladbury’s research has centered on the radiation testing and qualification of complex devices for spacecraft applications and development of statistical models in radiation hardness assurance. He has authored or co-authored over 80 technical papers in peer-reviewed journals and three short courses on various aspects of radiation hardness assurance. He also authored two dozen popularized articles on cutting-edge physics research while serving as Editor at Physics Today. On the manned side of NASA’s operations, Dr. Ladbury has worked on NASA’s Commercial Crew program and its Human Landing Systems and related infrastructure for the agency’s return to the Moon. Dr. Ladbury earned his Bachelor of Science degree in physics from Colorado State University and his PhD in experimental particle physics from the University of Colorado. In addition to his work in radiation physics and editor for Physics Today Magazine, Dr. Ladbury has worked as a physics professor at Pikeville College in Pikeville, KY and a science teacher trainer with the Peace Corps in the Savannah Region of Togo, West Africa. He lives in Mt. Airy, MD with his wife on 3 acres they share with the local wildlife.

All lectures in Hill Hall 202 unless otherwise specified