V. V. Vladimirsky and Charged-Particle Accelerators
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Physics of Atomic Nuclei, Vol. 68, No. 8, 2005, pp. 1263–1264. Translated from Yadernaya Fizika, Vol. 68, No. 8, 2005, pp. 1315–1317. Original Russian Text Copyright c 2005 by Koshkarev. TRIBUTE TO THE 90th BIRTHDAY OF V.V. VLADIMIRSKY V. V. Vladimirsky and Charged-Particle Accelerators D. G. Koshkarev* Institute of Theoretical and Experimental Physics, Bol’shaya Cheremushkinskaya ul. 25, Moscow, 117259 Russia Received February 28, 2005 Abstract—The main advances made in the field of accelerator science and technology at the Institute of Theoretical and Experimental Physics (ITEP,Moscow) within the ten years between 1953 and 1963 under the supervision of V.V. Vladimirsky and with his participation are described. c 2005 Pleiades Publish- ing, Inc. The proposal of E. Courant, M. Livingston, and on a residual vacuum in it, and imposing more strin- H. Snyder (1952) that concerned the creation of gent requirements on the nonlinear components of strongly focusing accelerators changed radically the the magnetic field. In order to solve these and other situation around the construction of high-energy ac- problems, Vladimirsky was able to organize a small celerators and, hence, in high-energy physics. How- group of researchers at ITEPwithin a short period of ever, this proposal was perceived rather ambiguously time, which included L.L. Gol’din, D.G. Koshkarev, in the Soviet Union. Some of the renowned authori- Yu.F. Orlov, and E.K. Tarasov as the main partici- ties on accelerator physics called attention to extraor- pants; I.M. Kapchinsky joined the group later. They dinarily stringent tolerances on magnetic elements in solved these problems successfully, and this permitted these accelerators and, in view of this, denied the pos- preparing physics projects of strongly focusing proton sibility of implementing this project in practice. Under synchrotrons in the shortest possible time. these circumstances, V.V. Vladimirsky demonstrated Koshkarev could understand the essence of the great scientific perspicacity and considerable courage problem that arose upon reaching the critical energy, when, contrary to the authorities’ opinion, he argued but the technological realization of this transition that the required tolerances, albeit stringent, are quite above it was dubious because of the underdevelop- attainable technologically. At the same time, the ment of radioelectronics at that time. Vladimirsky, to- “nothing for nothing” principle suggested that this gether with Tarasov, proposed a more reliable version project is in line with technical progress; therefore, it where was no critical energy at all—more precisely, should be started despite technological difficulties and where it was pushed to the energy region unattainable prepared for a practical implementation in the future. at a particular accelerator. Unfortunately, the pro- It was just due to Vladimirsky’s scientificintuition posed decision led to some complication of the design that the official leaders of our branch of industry of the accelerator magnetic system and to an increase decided to charge the staff of the Thermotechnical in the accelerator perimeter. Nevertheless, this sug- Laboratory [presently, the Institute of Theoretical gestion played a positive role, having confirmed the and Experimental Physics (ITEP, Moscow)] with efficiency of employing strong focusing in circular starting the development of a new generation of accelerators. strongly focusing accelerators under Vladimirsky’s The theory of nonlinear oscillations of protons supervision. in strongly focusing accelerators was developed by Even the first analysis of the situation indicated Orlov. This theory made it possible to determine at least four problems peculiar to strongly focus- the tolerances on the nonlinear components of the ing systems. First, there was the problem of a crit- magnetic field in the operating area of the accelerator ical energy that, if attained, impaired the stability of vacuum chamber. The effect of a residual vacuum longitudinal oscillations of accelerated protons. The on the dynamics of accelerated ions was studied remaining problems were associated with a greatly by Gol’din and Koshkarev, whose results enabled diminished transverse size of the magnetic elements them to determine an allowed value of the residual- and the vacuum chamber of the accelerator. This gas pressure in the vacuum chamber of a strongly called for completely changing the design of the ac- focusing accelerator. celerator vacuum chamber, strengthening tolerances Projects of two strongly focusing proton syn- chrotrons, which were the largest at that time, were *e-mail: [email protected] prepared on the basis of the studies performed under 1063-7788/05/6808-1263$26.00 c 2005 Pleiades Publishing, Inc. 1264 KOSHKAREV the supervision of Vladimirsky. The first project of a For their outstanding contribution to the prac- 7-GeV accelerator (U-7) was successfully commis- tice of linear-accelerator construction, the authors of sioned at ITEPwithin the shortest period in 1961. these innovations received, in 1968, inventor’s certifi- In 1967, a 70-GeV proton accelerator constructed in cate and, in 1991, a diploma for their discovery of a accordance with the second of these projects (it was new phenomenon of the focusing of charged-particle the greatest accelerator at that time) was put into beams in a varying electric field that is uniform along operation at the Institute for High Energy Physics, the beam axis. This research work was subsequently which was organized on the basis of this accelerator awarded a Lenin prize. near Serpukhov in Protvino, Moscow region, in 1964. In developing contemporary accelerators, the in- Injectors were needed for the circular accelera- tensity of the accelerated beam and its luminosity, tors under development, but only electrostatic gen- which characterize the possibility of producing ion erators could be used for that purpose at that time, beams of high electric-charge density, are the most their energy not exceeding 5 MeV. This energy was important parameters along with the ion energy. In barely sufficient for injection into U-7, but it was order to find out which accelerator parameters deter- absolutely inadequate for a more sizable accelera- mine the intensity and the luminosity of accelerated tor. Under these circumstances, Vladimirsky made ion beams, one needed a theory that would correctly the only possible decision to construct U-7 with an describe the dynamics of ion beams with allowance for 5-MeV electrostatic generator as an injector and to initiate, at the same time, the development of two the effect of the electromagnetic fields of accelerated new injectors—specifically, 25- and 100-MeV linear ions. Such a theory was developed by Kapchinsky proton accelerators for the U-7 and U-70 facilities, and Vladimirsky. The results of that study were first respectively. Vladimirsky invited Kapchinsky, whom presented at the conference on charged-particle ac- he knew well since their cooperation in the field of celerators in Geneva in 1959. The main result known radiolocation, to develop the projects of these strongly as the KV equation has been extensively applied both focusing linear proton accelerators. in theory and in the calculations of the dynamics of in- Since the advent of the strong focusing principle, tense ion beams in accelerators and charged-particle Vladimirsky realized that this principle can be of ad- storage rings. Later, the main ideas of that study were vantage not only in circular accelerators but also in developed in many investigations, but, undeniably, channels for ion-beam transportation in linear accel- the priority belongs to the discoverers, Kapchinsky erators. However, major difficulties were associated and Vladimirsky. with the use of magnetic quadrupole lenses in the The report of Vladimirsky at the International initial segment of a linear proton accelerator, where Conference on Charged-Particle Accelerators in the speed of accelerated particles is considerably be- Dubna in 1963 appeared to be his last research work low the speed of light; in some cases, their use even in the field of accelerators. In his report, Vladimirsky appeared to be impossible. A solution to this prob- demonstrated that U-70, which was then under lem via magnetic quadrupoles by electrostatic ones construction near Serpukhov, could serve as an was rejected, since the introduction of electrostatic appropriate basis for developing, in the Soviet Union, quadrupoles in the vacuum system would complicate the next generation of giant accelerators for the the accelerator design and reduce the reliability of energy region around 1 TeV. its operation. There remained only one way out— Vladimirsky’s disciples and colleagues regretted that which consisted in changing the design of the deeply that he stopped his active research in the field accelerating elements in such a way that the high- of charged particle accelerators after 1963, concen- frequency field would generate a quadrupole focusing trating his main efforts on studies in the realms of component, along with a dipole accelerating compo- elementary-particle physics, nuclear-force physics, nent. Vladimirsky was the first to find a rather simple and nuclear reactors. solution to this problem—he proposed using “horn” electrodes. Later, V.A. Teplyakov independently ar- Vladimirsky’s achievements in developing the rived at the same solution. Kapchinsky found an- complex of contemporary accelerator facilities in the other solution, suggesting to change the structure Soviet Union