BUDKER, GERSH ITSKOVICH

(b. Murafa, Vinitsk, Ukraine, 1 May 1918; d. Akademgorodok, Novosibirsk, U.S.S.R., 4 July 1977)

high energy physics, plasma physics, controlled thermonuclear synthesis, particle accelerators.

Budker was a leading specialist in high-energy physics whose colliding-beam accelerators revolutionized the efforts of experimentalists to understand subatomic structures and processes, and whose research institute at Akademgorodok, near Novosibirsk, Siberia, was a major center of nuclear physics.

Budker came from a poor rural Jewish family in the Vinitsk region of Ukraine, the son of an agricultural laborer who was shot by partisans during the civil war. Budker did not know his father, Itsak, who died a few months after he was born. He was raised by his mother, Rachel, and his grandmother. Budker was not very religious, but lived in and knew Jewish culture. He distinguished himself in school and as a ninth grader managed to complete his first scientific work under future Nobel laureate Igor Tamm at Moscow State University on the problem of the source of the energy-impulse tensor of an electromagnetic field in moving media. During his university entrance interview the 17-year-old was asked to explain the current food problems in the U.S.S.R. Always outspoken on a variety of issues, rather than hide his sentiments, he answered“collectivization” which had caused the deaths of millions of peasants in Ukraine due to famine. His entrance to the Physics Department was delayed by one year.

In the 1930s, Moscow State University was the site of ideological intrigues between scientists who accepted quantum mechanics and relativity theory, and those who questioned the epistemological issues raised by these fields of physics. They believed the new physics was incompatible with the Soviet philosophy of science, dialectical materialism. The intrigues led to the firing, arrest, and in some cases execution of scientists. Budker fortunately worked with Tamm, an active defender of the new physics.

Budker graduated in 1941, taking his last examination on 23 June, two days after the Germans had invaded the U.S.S.R. Budker immediately joined the army, and served in the Far East. After the war, Budker and other talented young scientists were conscripted into nuclear research. Budker joined Tamm and others connected with the theoretical department of Laboratory No. 2 (later the well-known Kurchatov Institute for Atomic Energy, and subsequently called the Russian Research Centre Kurchatov Institute), the lead institute in the atomic bomb project. Budker studied under Arkady B. Migdal. From the start Budker revealed a varied spectrum of interests. He undertook a series of studies on the theory of uraniumgraphite lattices and other research important to the design of reactors. He conducted these experiments on the first Soviet reactor, the F-1.

Owing to plans for the construction of a massive new proton accelerator in Dubna on the Volga River (now the Joint Institute of Nuclear Research) under Vladimir Veksler, Budker grew interested in high-energy physics and finished a paper that provided a new way to generate a proton stream, for which he received a State Prize in 1949. He studied how to use the tracks left in bubble chambers to demonstrate the presence of various subatomic processes. He also began to consider the physics of relativistic plasmas, research important to accelerator technology and thermonuclear reactors that contributed to the development of so-called open “magnetic traps” as devices for controlled thermonuclear synthesis (fusion). Igor Kurchatov welcomed Budker’s participation in work on the fusion problem. Only thirty years old, Budker had already distinguished himself as an outstanding, original thinker. Budker’s work on relativistic plasmas of electrons and ions gained attention of the world scientific community at the Geneva Conference for the Peaceful Uses of Atomic Energy (1956).

At this time Stalinist policies directly interfered with Budker’s career. In the late 1940s, Joseph Stalin apparently prepared for another major purge, in this case having singled out Jews. The secret police chief, Lavrenty Beria, claimed to have uncovered a plot by Jewish doctors to poison Kremlin leaders (the “Doctors'; Plot”). All Jews came under suspicion in all walks of life. Anti-Semitism was rife. It had been a central feature of life in the empire under the tsars, and had been growing again since the early 1930s. Jews faced official and unofficial quotas that restricted their access to higher education. They had gravitated to mathematics and physics as two relatively new fields with greater opportunities for entry. But in the environment of the Doctors' Plot, Budker and a number of other promising young researchers were prohibited from working on secret nuclear topics. Beria suddenly dropped Budker from fusion research in 1951 or 1952. It was later claimed that Beria had Budker’s dossier in his office safe, having it ready for the moment when he might arrest the physicist on trumped up charges but that Kurchatov had intervened personally to protect him.

Denied access to this research program, Budker instead used the opportunity to create his own group of theoreticians whose focus was the creation of a betatron-type accelerator that had the advantages of using direct current and producing a large stream of electrons. But Budker recognized that these machines also had significant limitations and eventually turned to the design of accelerators with colliding beams of charged particles. This led to the VEP-1 accelerator, built in the Siberian city of science, Akademgorodok, and a series of other more powerful colliding-beam accelerators that rivaled those in the west.

In order to understand the ultimate constituents of matter, physicists developed various machines – particle accelerators – to enable them to produce such charged particles as electrons, positrons, ions, protons and antipro-tons moving at high energies. They used charged particles produced in bunches, utilizing electromagnetic forces to accelerate them. Initially, they smashed these particles into fixed targets to produce other smaller particles using such devises as cyclotrons, synchrotrons and betatrons. Later they turned to colliding beams of particles that they smashed into each other. One of Budker’s major innovations was colliding beam accelerators. Along with such physicists as Austrian Bruno Touschek, who suggested injecting particles and antiparticles into a particle accelerator in different directions, then colliding them, Budker had advanced an idea to increase significantly the energy available for particle annihilations. Colliding beam machines had the advantage not only of higher interaction energies, but permitted experiments to be performed in extremely clean conditions. That is, observed interactions were not contaminated by the presence of secondary interactions as in the conventional fixed target machines.

Physicists produced particles in the accelerators in bunches. The goal in each machine was to increase “luminosity,” that is, increase the number of ions in each bunch and the revolution frequency, and/or by decreasing the bunch area. There were several major problems that faced physicists as they strove to reach higher energies. One is the fact that when two bunches of charged particles collide there is a very low probability of a collision of two particles. In the late 1940s and early 1950s, scientists built “strong focusing” machines to increase luminosity. One of those machines was built in Dubna, Russia, under Vladimir Veksler. Veksler’s work encouraged Budker’s interest in high energy physics, especially after he was temporarily denied access to nuclear weapons research by Beria.

In 1956, at the suggestion of Igor Kurchatov, head of the Soviet atomic bomb project and Laboratory 2, the mathematician Mikhail Lavrentev asked Budker to move to a new, planned city of science, Akademgorodok. Soviet leader Nikita Khrushchev had triggered de-Stalinization reforms with a so-called “Secret Speech” at the Twentieth Communist Party Congress in 1956. The de-Stalinization reforms extended to the scientific establishment. They included an effort to give greater autonomy to specialists, improve their productivity by several measures, and restore the importance of basic research. The scientific establishment grew rapidly. Leading personnel of the Soviet Academy of Sciences pushed to create a series of new research centers or science cities outside Moscow, Leningrad, and Kiev, Ukraine, and also outside the military research establishment. The major such science city, Akademgorodok, located 35 kilometers south of Novosibirsk in Siberia, brought together scientists in over twenty new institutes built in what had been a pine forest. Lavrentev selected Budker to direct the Institute of Nuclear Physics.

Given the impediments to their research in bureaucracy and political interference, Soviet scientists were quite productive. Indeed they were leaders in a number of fields, such as fusion and high-energy physics, in which Budker worked. Another impediment to novel scientific research was that entire fields of Soviet science might be dominated by one or two scientists at one or two major institutes. Budker no doubt sensed that intellectually he might have difficulty in pursuing his research interests in Moscow where well-established scientists held great authority and had the power of the purse. The construction of modern accelerators, which Budker realized would require open spaces, would also be prohibited at the Kurchatov Institute. Finally, Budker was an impetuous, out-spoken, and irreverent individual whose personality offended some of the more stodgy administrators and scientists in Moscow. Hence he had no doubts about the appropriateness of moving to Akademgorodok, where he might establish an institute where he had great latitude to set scientific directions, even though the institute would have to be built literally from scratch.

The Institute of Nuclear Physics was the leading institute in Akademgorodok in terms of size and authority. Massive even by Soviet standards, it covered several hundred hectares, had four particle accelerators, a foundry with cranes and other equipment, and several fusion devices. At its peak the institute had three thousand employees including thirty-five doctors of science and 130 candidates of science. Within a few years of its founding, in terms of publications, productivity, size, and reputation, it rivaled the other major nuclear research centers in the U.S.S.R.: the Leningrad Physical Technical Institute, the Ukrainian Physical Technical Institute in Kharkov, the Joint Center for Nuclear Research in Dubna, the Institute of High Energy Physics in Serpukhov south of Moscow, the Kurchatov Institute for Atomic Energy, and several military centers. In many respects it was the equivalent of a national laboratory in the United States or of CERN (Organisation Européenne Recherche Nucléaire) the major center in Europe.

Budker had three major foci of research (as did his institute). One was open thermonuclear systems. This research grew out of initial proposals of Tamm and Andrei Sakharov to create a toroidal magnetic thermonuclear reactor or tokamak. Budker suggested the idea of a direct axisymmetric magnetic system with enhanced magnetic fields at its ends (the “probkotron”). Although presented four years later because of secrecy restrictions, Budker’s first paper on open traps (1954) made quite an impression at the second Geneva conference on Peaceful Uses of Atomic Energy (1958). The fusion of lighter particles, ions or atoms, say deuterium, into heavier particles, for example lithium, releases tremendous quantities of energy. Budker’s theoretical and experimental investigations considered how to contain a plasma of the lighter particles in a reactor, fuse them into heavier ones, and transform the energy produced into electricity. Several experimental devices were built in Akademgorodok.

Since the Kurchatov and Ioffe institutes worked on tokamaks, other institutes focused on alternatives: the Physics Institute of the Academy of Sciences in Moscow, the Ukrainian Physical Technical Institute in Kharkov; and Budker’s institute. Budker and his group focused on various open-trap, multicell, multimirror machines where the plasma is created by the injection of fast molecular ions into a chamber. Such physicists as Dmitrii Riutov, Eduard Krugliakov, and Roald Sagdeev developed the theoretical foundations for this work.

Budker’s institute also worked on industrial applications for electron accelerators. The applications included improving insulating properties of polyethylene (with customers in the cable industry), production of artificial leather, disinfestation of grain, disinfection of waste water, and cutting and welding of metal. Along these lines institute workers built synchrotron radiation sources (storage rings of relativistic electrons) and detection equipment. Officials supported Budker’s expansion of production facilities for these accelerators for they viewed them as a symbol of a healthy relationship between science and production, while Budker recognized the importance of the production facilities in generating income to build still larger accelerators. Applications resulted in x-ray metallography, holography, structural analysis, spectroscopy, microscopy, and in isomers and geology.

The major focus of Budker’s work, and that which earned the institute’s and his own reputation, was the construction, perfection, and operation of increasingly large and powerful colliding-beam accelerators that attracted researchers from around the nation. Budker’s discoveries led to a Lenin Prize and other awards, however not the Nobel Prize. In 1976, Burton Richter (at Stanford) and Samuel C. C. Ting (at Brookhaven) shared the Nobel Prize for the use of colliding beams of high-energy electrons and positrons to discover the J/psi particle. Many Soviet—and western—physicists have argued that Budker ought to have shared in the prize for his pioneering work on accelerators using electron-positron colliding-beam experiments. Another important idea from Budker was electron cooling of proton beams, proposed in 1966, developed and tested in 1974 in his institute, and adopted and tested at such facilities as the European Center for Nuclear Research (CERN) and the Fermi National Accelerator Laboratory in Batavia, Illinois. In the early 2000s the Budker Institute continued to play a leading role in this research.

Budker claimed that western physicists would never have been able to perform in the environment of restrictions, secrecy, and bureaucratic impediments that faced Soviet physicists. He joked that the CERN accelerator, which straddles the boundary between Switzerland and France, would not operate in the U.S.S.R.: The charged particles going around the accelerator would have required a visa each time they crossed the border.

The revolutionary idea to use colliding beams of charged particles in accelerators was realized with some difficulty. The move from Moscow, the backwardness of industry, and bureaucracy slowed the efforts of Budker and his team. Yet in the twenty-five years that Budker was director, institute physicists made a number of important discoveries and measurements, including confirmation of quantum electrodynamics and more exact measurement of subatomic particles. The institute’s first machine, the VEP-1, an electron-electron storage ring produced beams of particles in 1963 and electron-electron scatterings in 1964. The resulting particles produced in collisions, their energies and trajectories contributed to the creation of a theory called quantum electrodynamics, a quantum field theory of electromagnetic force, that explains how charged particles behave. Richard Feynman, Julian Schwinger, and Sin-itero Tomonaga developed this theory, for which they received a Nobel Prize in 1965.

Under Budker’s direction, physicists next turned to electron-positron interactions, that were produced on the VEPP-2, on which physicists conducted the first experiments on elastic scattering of electrons at wide angles at energies of up to 700 MeV. and examined the instability of large currents in storage rings and accelerators based on the interaction of streams of particles. Electron-positron interactions were more difficult to produce, but given the zero charge of the reactions all energy and mass were devoted to the formation of new particles. VEPP-2 experiments on particle decay ran until 1970, when the accelerator was turned into an electron and positron booster for the VEPP-2M on which over fifteen years physicists have looked at processes occurring during electron-positron annihilation. While the VEPP-2M collider, the world’s first electron-positron phi-Factory (1975), had the lowest energy range of among similar machines in the world, its luminosity enabled it to remain the main, if not only supplier of electron-positron physics results in the range of 150 to 700 MeV. Next was the VEPP-3 series of experiments at high-energy intervals and measurement of the cross section of the creation of charged particles. As with its predecessor, the VEPP-3 was adopted as a booster for the VEPP-4, a 360-meter circumference electron-positron collider with energy to 5.5 GeV.

High energy physics was an area of intense competition between teams of researchers in different countries to assert scientific priority in publications, recognition and even Nobel Prizes. For example, Budker and his colleagues were well aware of the work of Italian teams who built electron-positron colliders after the suggestions of Touschek in Frascati, Italy, at the National Institute of Nuclear Physics, first the Anello d-Accumulazione (AdA) and later the ADONE colliding beam accelerators, and were able to stay ahead in many stages of the race especially after funding levels for the Italian teams could not maintained.

In addition to research using beams of electrons and positrons, Budker and his team developed colliders using beams of such heavy particles as ions, protons, and antiprotons. While ultimately not an entirely successful endeavor in reaching energies of 10 GeV for protons, Budker set forth two important innovations. One was the charge-exchange method of injection of protons which stabilizes protons in an equilibrium orbit in the accelerator and facilitates the storage of the maximum proton current. The second was electron cooling. Budker and Alexander Skrinskii proposed the possibility of attaining high luminosity proton-antiproton collisions by electron cooling. Electron cooling forms and stores dense narrow beams of heavy charged particles.

Budker first proposed the idea of electron cooling in 1966 that he described as a “damping method of the synchrotron and betatron oscillations of heavy particles” based on the effect of a sharp rise of the cross sections of heavy particle interactions with electrons at small relative velocities that he suggested would help to compress and accumulate proton and anti-proton bunches, leading to higher luminosity. Physicists tested this technique of injecting a beam of “cool” electrons into a straight-section orbit of a heavy charged particle beam to introduce an effective friction in his institute in 1974; the first electron cooler had a cooling length of 1 m. The time required for cooling, expected to be several seconds turned out to be 0.1 s. The electron beam moved with the same average velocity as the ion or proton beam, absorbing the kinetic energy of the heavy particles (ions or protons). This technique enabled shrinking ion beams of extremely high phase-space density. The main results of the Budker group were the discovery, explanation, and theory of super-fast and ultra-deep cooling; record results reached at the NAPM cooler ring of cooling time and temperatures, and longitudinal ordering of deeply cooled proton beams and consequent suppression of intra-beam scattering. Many physicists were skeptical of Budker’s idea of electron cooling. But he insisted upon following this possibility, even though it meant giving up his own project on a relativistic stabilized electron beam that was well advanced. Another way to increase luminosity by minimizing bunch area was to reduce the energy of the transverse motion or cooling, which requires some friction force. In electron-positron rings synchrotron radiation supplies the friction. For protons and ions, friction must be added. Simon van der Meer at CERN developed stochastic cooling for the SPS collider.

Many storage rings were built for synchrotron radiation. Budker saw an opportunity here to remove this radiation from machines especially for applications in biology because of its fine resolution, and in x-ray imaging for solid state physics and material science. Budker’s institute then developed, designed and sold high power accelerators for technological applications, some of them in serial production, with ninety of them operating abroad including in Japan, German, Poland, China and Korea with power ranges from 20 kW to 100 kW, and energy from 0.7 MeV to 3 MeV.

The decision to use the VEPP-3 as a booster followed a pattern used in high energy research at accelerator facilities around the world. His colleagues at the institute claimed that Budker was fond of saying, “a physicist must also be an engineer.” Second, Budker’s institute encountered increasingly tight budgets as other institutes and teams of physicists embarked on research with expensive large-scale equipment. Scientists at Serpukhov, Gatchina (outside of Leningrad), Erevan (Armenia), and Kharkov (Ukraine) were building large accelerators, which made it more difficult to attract young talented physicists to the institute than it had been during its founding years.

Third, teams of foreign scientists had moved beyond the parameters of the VEPP-3, so it made sense to move as quickly as possible to the VEPP-4. On the VEPP-4, researchers conducted experiments on mu, pi and v mesons and on symmetry nonconservation, and achieved results that reflected rapid progress in the field of high-energy physics at Stanford, DESY (the Deutsches Elektronen Synchrotron, outside of Hamburg), CERN, the French high-energy research facility Orsay, and elsewhere.

A democratic approach characterized Budker’s administrative style. Much of the research and funding for Budker’s institute came from the Ministry of Middle Machine Building, the ministry responsible for nuclear weapons. Budker hated the secrecy and bureaucracy of the ministry and sought another atmosphere. In all of the days of Budker’s directorship, the institute had only one secretary and, unlike most Soviet scientific administrators, it was a simple matter to see Budker. One only had to drop in.

Budker was extremely hard working and openly critical. He offered penetrating analysis of other researchers’ work on the spot, but meant nothing personal by it. He expected similar hard-hitting and open discussion within the walls of the Institute of Nuclear Physics. Every day at noon scientists gathered at the “round table” for a meeting of the academic council where they would hash out scientific, administrative, and other issues openly. In part, this openness was the essence of Akademgorodok, distant from Moscow and Leningrad and close scrutiny by Party officials of research activities and social issues both in physical and psychological senses. In Akademgorodok under the leadership of the physicists, scientists opened informal and formal social clubs where they discussed political issues, opened art exhibitions, and held festivals of folk singers that were impossible elsewhere in the country. Among the physicists who worked at or began their careers with Gersh Budker were Spartak T. Beliaev, Roald Z. Sagdeev, and Alexander N. Skrinsky.

In his last years, suffering from poor health, Budker declined to sign official Academy of Sciences condemnations of Andrei Sakharov for the latter’s outspoken criticism of Soviet human rights violations. There were rumors that Budker would have been removed from directorship of his institute had not a heart attack killed him in 1977.

In addition to being a scientific leader and an administrator, Budker was also an educator who welcomed the opportunity to teach at Novosibirsk University. He taught at the university (created new along with Akademgorodok) from its first days. He participated in so-called Olympiads of school children created to identify the most promising students for entry into the university and then the institutes of Akademgorodok.

Budker was neither an experimentalist nor a theoretician, neither a scientist nor an administrator, but all four, and as such he oversaw the successful creation of a huge scientific enterprise with several directions of activity. Although budgetary problems buffeted the institute after the breakup of the U.S.S.R. in 1991, Budker’s legacy persisted in the Budker Institute of Nuclear Physics which remained in the early twenty-first century one of the world’s leading centers of high energy physics.

BIBLIOGRAPHY

WORK BY BUDKER

“Relativistic Self-Stabilized Electron Beam.” [in Russian] Doctoral Thesis, Institute of Nuclear Physics, Akademgorodok, Novosibirsk, Siberia, 1958.

Proceedings of International Symposium on Electron and Positron Storage Rings. Saclay, France. (1966): Article II-1-1.

With G. Dimov and Vadim Dudnikov. Proceedings of International Symposium on Electron and Positron Storage Rings, Saclay, France. (1966): Article VIII-6-1.

“Effective Method of Damping of Particle Oscillations in Proton and Antiproton Accumulators.” Soviet Atomic Energy 22 (1967): 346–348.

With G. Dimov and Vadim Dudnikov. “Experimental Investigation of the Intense Proton Beam Accumulation in Storage Ring by Charge-Exchange Injection Method.” Soviet Atomic Energy 22 (1967): 384.

“Experimental Study of Electron Cooling.” English from Russian paper IYaF-76-33. Upton, NY: Brookhaven National Laboratory, 1976.

With Alexander N. Skrinsky. “Electron Cooling and New Possibilities in Elementary Particle Physics.” Soviet Physics— Uspekhi 21 (1978): 277–296.

OTHER SOURCES

Courant, Ernest David, Milton Stanley Livinston, H. S. Snyder. “The Strong-Focusing Synchrotron—A New High Energy Accelerator.” Physical Review 88 (1952): 1190–196.

Dikansky, Nikolai S., Igor N. Meshkov, Alexander N. Skrinsky. “Electron Cooling and its Applications in Elementary Particle Physics.” Nature 276 (21 December 1978): 763–767.

Josephson, Paul. New Atlantis Revisited. Princeton, NJ: Princeton University Press, 1997.

Parkhomchuk Vasily V., et al. “Electron Cooling: Physics and Prospective Applications.” Reports on Progress in Physics 54, no. 7 (July 1991): 919–947.

Parkhomchuk, Vasily V., Alexander N. Skrinsky. “Electron Cooling: 35 Years of Development,” Soviet Physics—Uspekhi43, no. 5 (2000): 433–452.

Shafranov, V. D. “The Initial Period in the History of Nuclear Research at the Kurchatov Institute.” Physics–Uspekhi 44, no. 8 (2001): 835–843.

Skrinsky, Alexander N., ed. Akademik G. I. Budker. Ocherki. Vospominaniia. Novosibirsk: Nauka, 1988. English version: G. I. Budker: Reflections and Remembrances, edited by Boris N. Breizman and James W. Van Dam. Woodbury, NY : AIP Press, 1994. Contains a list of Budker’s publications and some of Budker’s writings.

Zimmermann, Frank. “Review of Single Bunch Instabilities Driven by an Electron Cloud.” Physical Review Special Topics—Accelerators and Beams 7 (2004): 124801 [36 pages].

Paul Josephson