Interview conducted in April 2022

Viktor Ivanovich Bodnarchuk -  PhD. in physics and mathematics, Head of Department of Spectrometers Complex IBR-2 and Department of Neutron Investigations of Condensed Matter

I was interested in physics in high school and I had a vivid example, it was my elder brother that studied at the Moscow Institute of Physics and Technology. There was no issue of choosing a specialty, it was necessary to choose the appropriate university. After some thought, I decided to enter the MEPhI at the Faculty of Experimental and Theoretical Physics. I graduated from the Institute in 1994. It was a difficult time for the country, there was a collapse of the Soviet Union, the collapse of the system of distributing young specialists. For my diploma, I got to Nikolay Olegovich Elyutin at the research reactor at MEPhI. My area of study covered experimental methods of nuclear physics and the students from MEPhI came to Dubna from another department – Department of Solid State Physics. When it was time for distribution, my leader said that I should try to get to Dubna. At a scientific conference, together with my other teacher Yury Georgievich Abov, he recommended me to V. L. Aksenov that was Director of FLNP at that time. Viktor Lazarevich proposed Dmitry Anatolievich Korneev to be a supervisor for my research paper.
I remember that winter day in December, 1993 when I first came to Dubna. Dmitry Anatolievich met me at the entrance checkpoint and took me to his room, where we discussed what I could do in the laboratory. I must say that at that time the topic of my diploma work was assumed in accordance with the profile of the department where I studied but when I had already arrived to do my diploma, Dmitry Anatolievich had a very interesting task related to the fundamental properties of the neutron. He was so fired up with it that he told me: let's try it. And instead of the topic of detectors, I immersed myself in quantum mechanics, in the investigation of the wave properties of a neutron at the IBR-2 reactor. I must say, the time was interesting then, it was not clear what was happening in the country, the payment of salaries was delayed, but our work was in full swing, everyone was very passionate about it. D. A. Korneev was a creative person that was interested in both fundamental and methodological issues. With such a supervisor, I started to grow professionally. I learned about methods and techniques, gradually adopted all his richest experience that Dmitry Anatolievich had gained while designing facilities at the IBR-2 reactor. I can say that it was on the basis of this experience that I carried out all my further work in the area of techniques of working with polarized neutrons. In this sense, Dmitry Anatolievich Korneev is my biggest teacher that opened the way for me to research on neutron scattering. When I came to his group, the development of a new reflectometer with polarized neutrons REFLEX was under completion. A lot of methodological work had to be carried out to put the new facility into operation. Perhaps, that was why most of my later work concerned the methodological aspects of developing neutron scattering facilities or their individual units.
Unfortunately, Dmitry Anatolievich passed away early and I had to be responsible for REFLEX. Much was incomprehensible, there was some confusion, but gradually, it made sense. The gained experience allowed to meet tasks concerning maintenance of the facility, implementation of experiments and modernization. Later, some day, Alexander Isaakovich Ioffe from the Julich Research Centre (Germany) appeared in my life. He came to FLNP with a proposal to design a neutron spin echo facility on one of the beams of IBR-2, based on the idea that he had himself proposed. When implementing this task, I can say, I found my second teacher who I am very grateful to and I am glad that our cooperation is ongoing to this day. He has taught me a lot, I has gained colossal experience that he has got. I even went to him for a postdoc and we carried out a range of experiments in Jülich and Munich, proving the possibility of experimental implementation of the method proposed by him. Designing a new facility, we learned how to simulate neutron facilities in software packages, how to implement neutron experiments without neutrons, on computers. In these software packages, we simulated the spin-echo facility that Alexander Ioffe had conceived. Today, we implement it in hardware based on the same REFLEX reflectometer.
I understand that my methodological orientation was observed in the Department of Spectrometers Complex, so once, I was offered to go to work there in order to strengthen the methodological area in the development of facilities or units of facilities. I must say that I have received this offer more than once, but somehow I have never seen myself in another department, yet at some point I realized that I could move on and try myself in new areas. Recently, in 2018, I have accepted the offer of Sergey Kulikov and moved to his department as a deputy. My main task was precisely the development of methodological work based on the complex of spectrometers. In 2020, Sergey Kulikov became Head of the city and unexpectedly for me, I headed the Department of Spectrometers Complex IBR-2. Today, I make sure that firstly, all the work in the department is successfully carried out, so that all the obligations that we must fulfill in accordance with the topical plan and our own plans, are successfully implemented.
I also face the task of developing new areas that would become impulses for development. In particular, today, we extensively work to develop thermal neutron detectors based on a solid-state boron converter. The bulk of the detectors operating at our reactor are gas detectors with a converter from the gaseous helium-3 isotope. Helium-3 is an expensive product, its price increases year by year and today, there is a shortage of it on the market, so the transition to other converters is a topical issue not only for our reactor, but for all world neutron centres. New techniques for registering neutron radiation are being mastered and we have not to lag behind in this matter. We widely promote the area of developing detectors based on a boron converter. The required equipment is purchased, prototypes of detectors are produced and their properties are studied. Thus, we discover a new area of development.

Olga Tarantina
Photo by Tatyana Nagornaya