Vladimir V. Zheleznyakov

Russian Federation

1931-2022

Obituary:

ZHELEZNYAKOV Vladimir Vasilievich (1931-2022)
Born 28.01.1931 in Gorky (now N. Novgorod). In 1954 graduated from Gorky State University (now the University of Nizhny Novgorod, UNN), Department of Radiophysics, in 1957 completed the post-graduate studies under the supervision of Nobel laureate V.L.Ginzburg. Ph.D. (1959), in 1964 was awarded the Habilitation (Sc.) D. degree for the monograph “Radio Emission of the Sun and Planets”. Scientist and head of a department at the Radiophysical Research Institute (1957–1977), head of a department (till 2011) and counsellor of the RAS (to date) at the Institute of Applied Physics RAS, Professor of UNN (1968–2011). Corresponding Member of the RAS (1987), Academician (1997). Member of Bureaus of the Astronomy Council, the “Sun–Earth” Council and the Physical Sciences Division of the RAS (1990), IAU member (1991). Editor-in-chief of the “Radiophysics and Quantum Electronics” journal (1998–2016). The A.A. Belopolsky RAS’s award (1984).Specialist in theoretical radioastronomy, space plasma physics, theory of waves' propagation in plasma, high-energy astrophysics. Author of more than 200 scientific articles and 3 monographs: “Radio Emission of the Sun and Planets” (Nauka, Moscow, 1964, in Russian; Pergamon Press, 1970), “Electromagnetic Waves in Space Plasma” (Nauka, Moscow, 1977, in Russian), “Radiation in Astrophysical Plasmas” (Kluwer Academic Publishers, 1996; Yanus-K, Moscow, 1997, in Russian). In 2010 the book “Selected Writings” (IAP RAS, Nizhny Novgorod) was published for the 80th birthday of V.V. Zheleznyakov.
V.V. Zheleznyakov stated the crucial role of the cyclotron radiation mechanism for the formation of frequency peculiarities in spectra of the Sun's radio emission, optical radiation of magnetized white dwarves, and X-ray pulsars' emission. He was first to point to the significant influence of the relativistic velocity dependence of an electron's mass on the growth rate of cyclotron instability in weakly relativistic plasma, which made the basis for the gyrotron's theory. He created the theory of synchrotron instability, which shows the possibility of space synchrotron masers' existence. V.V. Zheleznyakov developed concepts of the thermal cyclotron radiation mechanism, which is the key element in the theory of slowly varying component of the Sun's microwave emission, and the plasma radiation mechanism, related to the combination scattering (merging) of plasma waves in the solar corona and their conversion to the electromagnetic radiation of twice the plasma frequency. Together with colleagues, he proposed and investigated the mechanisms of generation of the quasi-periodic structure (zebra-structure) in the radio emission of the Sun and the Crab Nebula's pulsar, based on the effect of double plasma resonance. Basing on his calculations of the cyclotron radiation pressure force acting on plasma in the magnetospheres of degenerate stars, V.V.Zheleznyakov conjectured and justified the existence of a new type of astrophysical objects, called radiative discons. Of great importance is the conducted by him quantitative description of the effects of linear transformation of electromagnetic modes in magnetoactive plasma during their propagation through areas with non-uniform transverse magnetic field and in neutral current sheets of the solar corona. He concluded that the latter exist on the basis of an analysis of the polarization of solar noise storms.
He was the author of many other fundamental results in the research of generation and propagation of electromagnetic waves in astrophysical plasma, particularly, in the theory of sporadic radio emission of the Sun, radio, optical and X-ray emission of pulsars, in the investigation of processes in plasma on magnetized white dwarves and neutron stars. About 20 members of V.V.Zheleznyakov's scientific school have become PhD and Habilitation (Sc.) D. in Physics and Mathematics, 4 of them are elected to the RAS.
Deceased 30th of December, 2022, in Nizhny Novgorod.