V. T. Tolok was born on 25th December 1926 in the small Ukrainian town Uman’. He was a member of the Soviet air force, 1943-1945, serving in the Black Sea region. He graduated from the Kharkov State University (physical-mathematical faculty, nuclear physics branch) in December 1951.

Beginning from 1952, and for many years, V. T. Tolok was an active research scientist and then the leader at Kharkov Institute of Physics and Technology (KIPT) (now the National Science Center KIPT), where he worked on the construction and operation of linear accelerators of protons and electrons, becoming, in 1955, head of the group for development of the electron accelerator LUE-5. This work led to the creation of a unique electron accelerator with characteristics that much exceeded the maximum achieved at that time: energy 5 MeV, electron current 10 A.

His work in plasma physics and fusion began in 1958 when he moved to the plasma physics department recently organized by Academician K. D. Sinel’nikov and became the head of the laboratory on investigation of RF properties of plasma. From 1966 up to 1987 he was the director of the plasma physics division, being head of all works relating to the plasma physics program, and became the Deputy Director of KIPT.

Starting in 1960, on the direct instruction of I. V. Kurchatov, V. T. Tolok was given the leadership responsibility for the development of the stellarator line at KIPT, carrying out the corresponding theoretical and experimental program. Under his direction a series of stellarator type fusion devices, well known to the international fusion community, were developed and assembled in KIPT. Among the devices of this sort that were built and successfully operated, the following should be mentioned: the first in the world stellarator-torsatron Saturn, and the whole family of other torsatrons: Vint-20, Uragan-1, Uragan-2, Uragan-3, and its modification Uragan-3M. The investigations of divertor plasma fluxes in these devices are among those which still influence the designs of torsatrons today.

V. T. Tolok was an initiator of studies on stellarator type devices of radiofrequency methods of plasma creation and heating. Since the early 1970s these methods have been successfully used on stellarators of the Institute for creation and maintenance of plasma with rather high parameters. He paid much attention to the application of new methods of plasma diagnostics and technology when developing new experimental devices, in particular to the application of cryogenic techniques in magnetic systems for stationary confinement of plasma, as was partly realized in the Crystal-1 torsatron.

Simultaneously with the realization of the Uragan program, two other important programs, Beam and Jupiter, were conducted under leadership of V. T. Tolok. A series of electromagnetic traps of the Jupiter type were built up, and the investigations demonstrated that the plasma particle losses correlate well with the classical losses law. Due to support of V. T. Tolok, a significant program on development of quasi-stationary plasma accelerators (QSPA) was started in KIPT, and thd most powerful in the world plasma accelerator was put into operation in 1990, which is actively used in radiation technologies.

The program Bulat has to be especially noted, in which V. T. Tolok has made a determinative contribution in development of investigations in the field of high energy plasmochemistry, i.e., building up the technology for producing new materials in the form of coatings on industrial articles for multifunctional purposes. The experimental and scientific basis for development and perfection of deposition of antiwear coatings was founded, and a series of Bulats were developed: many hundreds of them were introduced in the industry of the USSR. The license for the Bulat technology was bought by the USA Company Multi-ARC.

In 1988 V. T. Tolok organized and became the head of a new vacuum-plasma-technology laboratory in the physical-technical faculty of the Kharkov Karazin University. The main objective of the laboratory was to bring about an improvement of vacuum-plasma technologies on the Bulat installations.

Up to his death, V. T. Tolok was an Adviser to the Director General of NSC KIPT and an honorary Professor of NSC KIPT. He took an active part in the realization of a wide international cooperation with the fusion laboratories over the world: for 14 years he actively participated in work of USSR-USA fusion coordinating committee. He supervised a great number of Candidates and Doctors of Sciences, and is the author and co-author of more than 200 scientific publications. He was awarded with several decorations: the Patriotic war (II degree), For Courage (III degree), the October revolution, the Rank of honor, and many military and labour medals.

Many of his colleagues contributed to this obituary, including: I. M. Neklyudov, I. N. Vishnevsky, A. S. Bakai, A. N. Dovbnya, V. F. Klepikov, N. F. Shul’ga, I. E. Garkusha, I. A. Girka, V. S. Voitsenya, A. V. Volobuev, A. M. Egorov, O. S. Pavlichenko, V. V. Chechkin, O. M. Shvets

Correspondence should be directed to V. S. Voitsenya: voitseny@kipt.kharkov.ua,