Wilson, Robert Rathbun

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WILSON, ROBERT RATHBUN

(b. Frontier, Wyoming, 4 March 1914;

d. Ithaca, New York, 16 January 2000), high-energy physics, particle physics, particle accelerators, Fermi National Accelerator Laboratory.

Wilson is remembered for his bold and imaginative designs of particle accelerators, for his leadership of experimental physics research at Los Alamos, New Mexico, during the period of the Manhattan Project, and for building the Fermi National Accelerator Laboratory, which for more than thirty years offered the international particle physics community the world’s highest-energy protons for fundamental research in an aesthetically designed environment.

Early Years. Wilson’s father, Platt Wilson, the son of an Iowa preacher, was a civil engineer who worked in both the coal mining and automobile industries. Platt subsequently entered politics, became chairman of the Democratic Party in Wyoming, and was later elected a state senator. Robert Wilson’s mother, Edith Rathbun, came from a family of ranchers who had moved to Wyoming after the California gold rush. The Rathbun family’s high regard for learning had a formative influence on Robert Wilson.

Spending much of his young years on his family’s cattle ranches in Wyoming, Wilson became a skilled horseman who could throw a lariat and ride after cattle. He initially aspired to become a cowboy. The experience of spending long periods alone riding great distances with a pack horse, reading the sky for weather, and generally pitted against nature, nurtured Wilson’s resourcefulness and helped him develop a sense of closeness with nature, as well as the belief that he was “unique in the world.” He felt that his early experiences of fixing tools and apparatus in the blacksmith’s shop helped him build “the confidence that with your own hands you could build large contraptions and make them work” (Weart, 2000). Experimenting in his mother’s attic, Wilson taught himself practical skills, such as blowing glass, which he drew on in building a mercury vacuum pump and a Crooke’s tube. He also read insatiably in his local library, where he found role models in works of literature that proved more formative than any of the schools he attended, a different school each year after his parents separated while he was still in grade school. The hero of Sinclair Lewis’s novel Arrow-smith exemplified for Wilson the noble scientist seeking practical solutions in the service of humanity. Going back and forth between his parents, he was often in the care of his maternal grandmother, Nellie Rathbun, the granddaughter of the abolitionist John G. Fee, who founded Berea College, a racially integrated school, in pre–Civil War Kentucky. Nellie helped to instill b social and educational values into Robert. Although he remained shy and withdrawn through high school and college, rarely speaking up in class, he readily learned from his father the value and skill of rhetoric and storytelling (Weart, 2000, pp. 151–154).

Physics Training under Lawrence. Following in the tradition of his maternal family, Wilson pursued a college education, gaining admission in 1932 to the University of California at Berkeley, despite his undistinguished high school record. Like many physicists who began their studies during the Great Depression, he enrolled in an electrical engineering program, which offered the promise of future employment. But beyond his love for nature and philosophy he discovered his passion for physics, which he proceeded to teach himself as a freshman. A particular attraction was the nuclear physics research pursued at the Radiation Laboratory directed by Ernest Orlando Lawrence, who had recently invented the cyclotron in 1930. One day during Wilson’s freshman year, he stood in the rain peering through a window into the Rad Lab. When he was invited inside, he was shown the cyclotron and he decided on the spot that working with such machines was what he would do in life (Weart, 2000, p. 157). Within several years he would join Lawrence’s “boys,” the group of graduate students, including M. Stanley Livingston, Edwin McMillan, Philip Abelson, Luis Alvarez, and Milton White, who worked around Lawrence and his cyclotrons.

During his junior year, Wilson nervously asked Lawrence whether he would be willing to sponsor his independent project. Lawrence directed the shy young man to Harry White, under whom Wilson invented a vacuum switch. By the time he entered his senior year, Wilson was conducting original research on the lag time of the spark discharge. Staying on for graduate study under Lawrence, Wilson took up a range of physics problems, including the theory of the cyclotron. An invention resulted: the waxless cyclotron vacuum seal, which became known as the “Wilson seal.”

Wilson experienced Lawrence’s laboratory as an adventuresome, special place, without hierarchy, but with Lawrence, affectionately known as “the Maestro,” very much in charge. Wilson regretted the subtle change he noticed over his five years there, as Lawrence gradually withdrew from working alongside his “boys” into his office to deal with administrative matters, leaving a microphone hanging in his place. Wilson nevertheless came away from his training under Lawrence with many valuable lessons, such as: “If you want something to come true, you can make it come true just by pushing like hell.” or “There are many ways of getting to a result.” or “If you tried, it was a question of being optimistic or pessimistic.” Wilson’s thesis experiment on proton-proton scattering failed because he could not make the cyclotron work well enough. But as Wilson could not delay moving to Princeton University to begin his appointment there as an instructor in physics, he wrote his thesis in 1940 on the theory of the cyclotron. He did until the last possible moment try to make the cyclotron work, arriving late for his wedding to Jane Inez Scheyer in August 1940 (Weart, 2000, pp. 175–185). Jane and Bob Wilson were to enjoy a long and happy marriage of fifty-nine years. They had three sons, Daniel, Jonathan, and Rand.

Princeton, Los Alamos, Cornell. At Princeton, Wilson continued to pursue proton-proton scattering, and he used the Princeton cyclotron to aid the experimental work at Columbia University of Enrico Fermi and Herbert Anderson leading to their successful demonstration of the first nuclear chain reaction at the University of Chicago. In subsequent work, Wilson showed that a resonant mode of fission occurs. He also invented the electromagnetic isotope separation method known as the “Isotron method,” a project canceled early in 1943. At that time, his group’s members and its apparatus were shipped to Los Alamos, the secret laboratory in New Mexico under the direction of J. Robert Oppenheimer, organized in 1942 to build the atomic bomb. As a pacifist, Wilson initially felt that he could not be involved in the war. But as Nazism took hold, he “grew more and more uneasy.” As he later explained, “If Hitler indeed conquered the world, could I bear to stand by and watch it happen, could I bear to think what life in such a world might be like?” (Wilson, 1970a, p. 30). Reversing his position on the war, he accepted an invitation to work on radar at the Massachusetts Institute of Technology “Radiation Lab,” which Lawrence was then helping to organize. Soon Wilson decided that he would be more helpful to his country if he worked on problems of nuclear physics. He moved to New Mexico.

Wilson flourished in the austere environment of Los Alamos, where military deadlines brought physicists and chemists to employ practical methodologies to compensate for their incomplete theories and limited experimental knowledge of nuclear physics. Following in his father’s footsteps, Wilson dabbled in Los Alamos politics, serving on the Town Council and later as the council’s leader. When the laboratory decided that the Harvard cyclotron was the accelerator best suited for its nuclear physics research, the military sent to Harvard a team, including Wilson, instructed to purchase the cyclotron under the pretext that the accelerator was needed for medical work in Saint Louis. The Harvard physicists suspected the team’s underlying motive and told its members that it could have the cyclotron without payment if the accelerator were used in the fission project. But despite Wilson’s embarrassment, the army personnel obeyed orders and stuck with their story, paying Harvard a large sum for the Los Alamos cyclotron (Hoddeson et al., 1993, pp. 63–65). As the leader of the cyclotron group, Wilson then proceeded to study a number of critical issues essential to building an atomic bomb, among them, how many neutrons emerge on average per fission of an atom of uranium or plutonium, and whether neutrons are emitted from uranium instantaneously or with some delay.

The discovery in April 1944 that pile-produced plutonium contains a spontaneously fissioning isotope caused a massive reorganization at Los Alamos aimed at building a plutonium implosion bomb in time to be useful in the war. Wilson succeeded Robert Bacher as head of the Experimental Physics Division when Bacher was asked to lead the new implosion gadget division. In July 1945, Wilson experienced the Trinity test of the implosion bomb as a “re-awakening from being completely technically-oriented” (Wilson, 1970a, p. 33). He subsequently criticized the decision to drop atomic bombs on Hiroshima and Nagasaki and became a founding member of the Federation of Atomic Scientists, an organization created explicitly to “promote humanitarian uses of science and technology.” Wilson served as chairman in 1946. He resolved to work henceforth on nuclear energy only as “a positive factor for humanity” (Wilson, 1970a, p. 33). In 1946 he left Los Alamos to join the physics faculty at Harvard University as an associate professor. There he designed a 150 MeV cyclotron and explored using it in cancer therapy.

In February 1947, Wilson moved to Cornell University as a full professor, once again succeeding Bacher, this time as the director of Cornell’s Laboratory of Nuclear Studies. He made one of the first applications of the Monte Carlo method, a procedure that grew out of calculations made at Los Alamos in developing the atomic bomb, which provides approximate solutions to problems by performing statistical sampling experiments on a computer. Using this method, Wilson developed a way to produce very high temperatures in plasmas by producing an imploding shock wave in an ionized gas, and separated the nucleon’s electromagnetic form factors through elastic, electron-nucleon scattering experiments. Over his twenty years at Cornell, Wilson built four electron synchrotrons, each more powerful than the previous one, culminating in Cornell’s 10 GeV synchrotron. The 1.5 GeV synchrotron in this series, later upgraded to 2.2 GeV, was the first accelerator to use the b-focusing principle invented in 1952 by Ernest Courant, Stanley Livingston, and Hart-land Snyder. All four synchrotrons reflected Wilson’s emerging philosophy of frugal design from both a technological and economic point of view, a philosophy based on the approaches to physics he had experienced working under Lawrence and Oppenheimer. A consequence of Wilson’s philosophy was that “something that works right away is over-designed and consequently will have taken too long to build” (Wilson, 1966, p. 235).

Wilson was happy at Cornell, but a part of him yearned to express his emerging artistic sensibility. An opportunity arose in the fall of 1965 during an instrumentation conference he attended in Frascati, Italy. There, hearing a group of Berkeley colleagues present their plans for a proton synchrotron with the unprecedented energy of 200 GeV, Wilson was offended by the machine’s unimaginative design and high cost. After the meeting, while taking classes in drawing at La Grande Chaumière in Paris, he found himself “consumed with a passion for designing machines.” In this romantic setting he drew images of magnets, rather than of the nude models, as he worked out frugal designs for synchrotrons. Considering Gothic cathedrals and accelerators in the same terms, he asked how could both “express the aspirations and spirituality of their age?” (Wilson, interview by Lillian Hoddeson, 12 January, and 8, 10, and 12 May 1978.) He then sent a critical note to Edwin McMillan, Lawrence’s successor at Berkeley, explaining why he considered Berkeley’s design “much too conservative,” “lacking in imagination,” and “without enough regard for economic factors.” Wilson said he feared the Berkeley machine’s high cost would kill the exciting 200 GeV project and endanger a future 600–1000 GeV machine (Wilson, 1965). He included with his note several alternative designs of his own, including one for a 200 GeV machine, priced at roughly $100 million with completion in three years, offering a striking contrast to Berkeley’s design estimated at $348 million with completion in seven years. In December 1966, the Atomic Energy Commission (AEC) selected a site for the new machine in Weston, Illinois, a suburb of Chicago. Early in the following year Wilson accepted the challenge of building the world’s most powerful accelerator in the American Midwest.

Fermi National Accelerator Laboratory. The Illinois site, 6,800 acres, consisting mainly of farmland in DuPage County, became a blank canvas for Wilson to express his aesthetic and noble ideals for the new laboratory, which he named the National Accelerator Laboratory (NAL) to indicate that it would offer democratic access to anyone whose work had sufficient merit. He called for frugal and functional components, combined harmoniously into a design which would contribute to society “not only in a technical but also in an esthetic, social, and philosophical sense” (Wilson, 1968, p. 490). Wilson would continue to express his artistic sensibility in his dream laboratory, and

throughout the rest of his life, in the form of sculptures, drawings, and architecture. With his politically skilled deputy director, Edwin Goldwasser, Wilson planned a physics community reflecting great beauty, based on civil rights and diversity—a laboratory that would inspire solutions to a broad range of social, economic, and cultural, as well as physics, problems. Into his holistic design of the laboratory, Wilson projected his respect for nature and the environment.

To help lobby against racial discrimination in Du Page County, Illinois, Wilson and Goldwasser designed NAL’s official human rights policy “to seek the achievement of its scientific goals within a framework of equal employment opportunity and of a deep dedication to the fundamental tenets of human rights and dignity” (NAL, 1968b). At the laboratory’s Congressional authorization hearings in 1969, Wilson responded to Senator John Pastore’s question about what the laboratory would offer for national defense:

It only has to do with the respect with which we regard one another, the dignity of men, our love of culture … it has to do with: Are we good painters, good sculptors, great poets? I mean all the things that we really venerate and honor in our country and are patriotic about.… it has nothing to do directly with defending our country except to help make it worth defending. (Wilson, 1970a, p. 113)

By taking risks on some twenty aspects of the design of the new accelerator, Wilson saved about $5 million on each and found ways to stretch the performance of the components so that he could raise the energy of the accelerator to 500 GeV, yet stay within his limited budget. One of his riskiest gambles was to design the accelerator’s tunnel so it “floated” on the glacial till beneath the topsoil, thus avoiding the need to anchor the tunnel in bedrock using pylons. He further economized by accelerating the building schedule to reduce personnel costs. Advancing the deadline for installing the Main Ring of the accelerator by six months (from 1 January 1972 to 1 July 1971) had the effect of moving the schedule for completion of the accelerator by an entire year. “We knew something would fail,” Harvard’s Norman Ramsey noted, “but we figured it would be much less expensive to fix the failure than to play it safe with all twenty items” (interview by Lillian Hoddeson, 26 and 27 February 1980).

Yet as Wilson’s ambitious mid-1971 deadline for completing the Main Ring’s installation approached, no one was prepared for the traumatic events that dashed his dream of completing the accelerator a year ahead of schedule. Magnets began to fail at an alarming rate as the weather grew warmer. There is still disagreement about exactly what caused these failures. The crisis caused considerable trouble for experimenters who had arranged their sabbatical leaves based on Wilson’s optimistic projections. Wilson coped with the crisis in his own way. One day in January 1972, he entered the control room and pulled out a small book from which he read in French from the Song of Roland, an eleventh-century chanson de geste (epic ballad) whose original intent had been to inspire Charlemagne’s soldiers during the Crusades. In time many of the Main Ring magnets were replaced with reconditioned or newly built magnets. The milestone energy of 200 GeV was finally achieved on the afternoon of 1 March 1972, surpassing the 76 GeV record at the Serpukov machine in the USSR, and recapturing the energy lead for the United States. While many of the risky elements of the accelerator had failed, more had succeeded, so that much money was saved on the whole project. Wilson triumphantly announced to the AEC that the project had come in under budget and ahead of schedule (even if not as far ahead as he had hoped).

By the time NAL was renamed Fermi National Accelerator Laboratory (Fermilab) in 1974, in line with a 1969 AEC decision to honor Enrico Fermi, experimental research areas were in operation. The application of Wilson’s philosophy of frugality to the experimental program meant that most of the experimental areas were “rough-and-ready places,” as Wilson later described them (Wilson and Kolb, 1997, p. 356). The discomforts of experimenting at Fermilab in its early years bred widespread criticism from experimenters who did not agree with Wilson that a laboratory was better off providing minimal facilities because expensive ones “may tend to paralyze better developments later on,” as Wilson had already cautioned McMillan in 1965 (Wilson, 1965).

These “better developments” included a new accelerator of higher energy than the Main Ring. Wilson began working on this upgrade, which he called the Energy Doubler (it was referred to during the nation’s “energy crisis” as the Energy Saver, and later as the Tevatron), even before completing the Main Ring. His imaginative plan, revealed in March 1971, called for doubling the energy to a trillion electron volts (1 TeV), saving power as well, using the phenomenon of superconductivity as an “elixir to rejuvenate old accelerators and open new vistas for the future” (U.S. Congress, 1971; Wilson, 1977, p. 23). The in-house magnet factory that Wilson had built to help create the Main Ring’s magnets, served as a research tool in developing the innovative superconducting magnets: by building hundreds of small-scale (and sometimes full-scale) prototypes, it was possible to observe their behavior and use the results in designing better magnets. Wilson estimated that this Energy Doubler would cost less than $20 million, roughly the amount left over from building the Main Ring, but the Washington-based AEC rejected Wilson’s request to use this money for building the Doubler.

The funding prospects for the Doubler continued to worsen. Wilson had dealt comfortably with the Congressional Joint Committee on Atomic Energy (JCAE) and the AEC itself throughout the 1960s and early 1970s. His Berkeley and Los Alamos connections gave him an insider’s conduit to the leadership of these funding sources. But when President Gerald Ford’s administration transformed the AEC into two new bodies, the Energy Research Development Agency (ERDA) and the Nuclear Regulatory Commission (NRC), Wilson’s advantage disappeared. Moreover, when Wilson turned to ERDA in early 1976 to request construction funds for the Doubler, he found the agency committed to ISABELLE, Brookhaven National Laboratory’s superconducting colliding beams accelerator. The reorganization in October 1977 that produced a new Department of Energy (DOE), replacing ERDA, further crippled Wilson’s ability to secure funding for his laboratory. By this time, Wilson was painfully aware of the multiple tensions inherent in his vision for Fermilab, for example, between the notion of a large collaborative venture and the lone, self-reliant frontiersman scientist, pursuing his individual initiatives. That his laboratory had become a vehicle for the rise of what he considered bureaucratic megascience was a great disappointment to Wilson. On 9 February 1978 he submitted his resignation as the director of Fermilab.

Last Years. Wilson continued to work on Fermilab’s programs, especially the Doubler, after his retirement from the laboratory. He also continued to lecture and consult on many topics ranging from magnet design to architectural and artistic design. He held a joint appointment in the Department of Physics and the College of the University of Chicago from 1967 to 1980 and became the Peter B. Ritzma Professor there in 1978. He was appointed the I. I. Rabi Visiting Professor of Science and Human Values at Columbia University in the fall of 1979 and the Michael Pupin Professor of Physics in 1980. In 1982 he returned to Cornell as a professor emeritus. He passed away in Ithaca on 16 January 2000, having suffered a stroke three years earlier, from which he never recovered. His ashes were buried on 28 April 2000 in the nineteenth-century Pioneer Cemetery on Fermilab’s site.

Wilson received many honors during his life. He was elected to the National Academy of Sciences in 1957, awarded the National Medal of Science in 1973, and the Enrico Fermi Award in 1984. In 1985 he became president of the American Physical Society.

BIBLIOGRAPHY

WORKS BY WILSON

“Radiological Use of Fast Protons.” Radiology 47 (November 1946): 487–491.

Letter to Edwin McMillan, 27 September 1965.

“An Anecdotal Account of Accelerators at Cornell.” In Perspectives in Modern Physics: Essays in Honor of Hans A. Bethe, edited by Robert Marshak. New York: Interscience Publishers, 1966.

“The Richtmyer Memorial Lecture—Particles, Accelerators and Society.” American Journal of Physics 36 (June 1968): 490–495.

“Conscience of a Physicist.” Bulletin of the Atomic Scientists 26 (June 1970a): 30–34.

“My Fight against Team Research.” Daedalus 99 (Fall 1970b): 1076–1087.

“The Tevatron.” Physics Today 30 (October 1977): 23–30.

With Adrienne W. Kolb. “Building Fermilab: A User’s Paradise.” In The Rise of the Standard Model: Particle Physics in the 1960s and 1970s, edited by Lillian Hoddeson, L. Brown, M. Riordan, et al. New York: Cambridge University Press, 1997, pp. 338–363.

OTHER SOURCES

Crease, Robert P. “Quenched! The ISABELLE Saga.” Physics in Perspective 7:3 I (December 2006) 330–376, II (December 2006) 404–452.

Goldwasser, Edwin L. “Robert R. Wilson: A Man for All Seasons.” American Physical Society. Long Beach, CA. 1 May 2000.

Heilbron, John, and Robert Seidel. Lawrence and His Laboratory, vol. 1, A History of the Lawrence Berkeley Laboratory. Berkeley: University of California Press, 1989.

Hoddeson, Lillian. “Establishing KEK in Japan and Fermilab in the US: Internationalism, Nationalism and High Energy Accelerator Physics during the 1960s.” Social Studies of Science 13 (1983): 1–48.

Hoddeson, Lillian, Laurie Brown, Michael Riordan, et al., eds. The Rise of the Standard Model: Particle Physics in the 1960s and 1970s. New York: Cambridge University Press, 1997.

Hoddeson, Lillian, Paul W. Henriksen, Roger A. Meade, et al. Critical Assembly: A Technical History of Los Alamos during the Oppenheimer Years, 1943–1945. New York: Cambridge University Press, 1993.

Leposky, George. “What’s the Best Way to Build a $250 Million Atom Smasher?” Inland Architect (August/September 1960), p. 24.

McDaniel, Boyce, and Albert Silverman. Obituary. Physics Today 53 (April 2000): 82–83.

National Accelerator Laboratory (NAL). “Design Report.” January 1968a.

———. “Policy Statement on Human Rights.” 15 March 1968b.

Sokolov, Raymond. “Fermilab: Utopia on the Prairie.” Wall Street Journal, 11 February 1983.

U.S. Congress. AEC Authorizing Legislation Fiscal Year 1970: Hearings before the Joint Committee on Atomic Energy. 91st Cong., 1st sess., on General, Physical Research Program, Space Nuclear Program, and Plowshare. April 17–18, 1969, part 1. Washington, DC: U.S. Government Printing Office, 1969. See pp. 112–118.

———. AEC Authorizing Legislation Fiscal Year 1972: Hearings before the Joint Committee on Atomic Energy. 92nd Cong., 1st sess., on Physical Research, Space Nuclear, and Nuclear Waste Management Programs. March 9, 16, 17, 1971, part 3. Washington, DC: U.S. Government Printing Office, 1971. See pp. 1191–1247.

Weart, Spencer. “From Frontiersman to Fermilab: Robert R. Wilson.” Physics in Perspective 2 (June 2000): 141–203. Based on interview of Wilson by Weart, 19 May 1977.

Lillian Hoddeson

Adrienne Kolb