Dr. Robert K. Osborne

Hailey Wilson
February 6, 2019

Submitted as coursework for PH241, Stanford University, Winter 2018

Background

Fig. 1: Los Alamos National Laboratory. (Source: Wikimedia Commons)

Dr. Robert "Bob" Kidder Osborne (1921-2009) is considered one of the most notable weapons engineers to ever work at Los Alamos National Laboratory (Fig. 1). [1] After growing up in Kansas City, Missouri, Osborne left to study at the Massachusetts Institute of Technology (MIT). While at MIT, Osborne completed a Bachelors of Science in Physics and ultimately a PhD in Physics, graduating in 1947. [1] During his time as a student at MIT, Osbourne completed a thesis on nuclear isomers of lead and research on the decay of radioactive substances. [1] He remained a teacher at MIT until his move to Los Alamos Scientific Laboratory (now Los Alamos National Laboratory - LANL). This transition occurred during the summer of 1949, when he became the thirteenth member of the Los Alamos Scientific Laboratory's nuclear weapons design group. [1]

4 years before Osborne's start at LANL, the United States dropped two atomic bombs during the end of World War II. During this Cold War time period, the United States was quickly improving, testing, and creating nuclear weapons. Osborne therefore was a member of the growing field of nuclear designers, contributing to the array of United States nuclear weapons. In fact, until 1952 all American nuclear weapons were made at LANL, including the World War II-ending atomic bombs. [2]

Famous Contributions

During Osborne's 32 years at Los Alamos National Laboratory he was able to be instrumental in several nuclear advancements. While each of his contributions was important, Osborne has some that stand out above the rest. For three of his works, Osborne is considered the "Father": One-Point Safety, Hydronuclear Testing, and the Primary for the W76 Warhead. [1]

Fig. 2: W76 Warhead. (Source: Wikimedia Commons)

"One-point safety" is a safety measure to ensure that nuclear yield is not detonated when there are accidents with nuclear weapons. When the problem was determined, Osborne was immediately asked to develop and test one-point safety. [1] During the mid-1950s, Osborne and fellow scientists conducted several tests on one- point safety, including Project 56 and Project 58. Following these tests, Osborne joined the committee to determine how testing would continue. The resulting official definition of a one-point safe nuclear weapon is one that presents no greater .0001% chance of achieving a nuclear detonation in the event of a detonation. [3]

Another of Osborne's great successes was in the creation of hydronuclear tests. The tests were approved by President Dwight Eisenhower to be conducted at Los Alamos National Laboratory, and were carried out by Osborne and the previously-mentioned one-point safety committee. The hydronuclear tests continued the earlier one-point safety tests, and provided data an appropriate nuclear materials. [?] In order for an experiment to be classified as hydronuclear, the fission energy released must have been small enough to pass the one-point safety standard. [4]

Later on Osborne also worked substantially on warheads, the portion of missiles that contain explosives. The Defense Department tasked Osborne and his team members from Los Alamos and Livermore to create a new primary design for a warhead to aim at multiple targets. [1] Fortunately, Osborne had experience through his nuclear design background in working on primary designs. He lead the Los Alamos portion of the team, testing several possibilities. In the end, Osborne's design prevailed and became the primary design for the popularly known as the W76 warhead (Fig. 2).

Legacy

Though Osborne has since retired and passed, his legacy still lives on at Los Alamos National Laboratory and in the Nuclear Science field. His works, both above and otherwise, all contributed to future advances within his fields. One-point safety was since adopted as the United States standard, and still remains imperative for all nuclear weapons in America today. The W76 Warhead lives on still as well. Though modifications on the warhead have since been made, the W76 design is still used in United States warheads. Of all American warheads, the W76 still remains the most abundant. [1] In other ways Osborne's legacy has lived on as well. His notes and publications are still very commonly used by Los Alamos engineers and designers working on modern U.S. nuclear weapons. [1] Through these written journals, Osborne will continue to advance nuclear weapons far beyond his years.

© Hailey Wilson. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.

References

[1] J. S. Best, "The Giants of the Nuclear Testing Era: The Works of Robert K. Osborne," Los Alamos National Laboratory, LA-UR-18-27654, 4 Sep 18.

[2] H. Gusterson, Nuclear Rites: A Weapons Laboratory at the End of the Cold War (University of California Press, 1996).

[3] "Nuclear Explosive and Weapon Surety Program," U.S. Department of Energy, DOE O 452.1E, 26 Jan 15.

[4] R. N. Thorn and D. R. Westervelt, "Hydronuclear Experiments ," Los Alamos National Laboratory, LA-10902-ms,February 1987.