Ilja Frank dies in Moscow at the age of 81.

Ilja Frank works as Director of the Neutron Laboratory of the Joint Institute of Nuclear Investigations. The neutron fast-pulse reactor (IBR) is at that time under construction. The reactor is then used in the development of neutron spectroscopy techniques.

Ilja Frank is awarded the degree of Doctor of Physico-Mathematical Science at the Moscow State University.

Ilja Frank receives the Nobel prize in Physics with Pavel A. Cherenkov and Igor Y. Tamm "for the discovery and the interpretation of the Cherenkov effect".

Ilja Frank joins the P.N. Lebedev Institute of Physics of the U.S.S.R. Academy of Sciences (which shortly is moved to Moscow into the Institute of Physics). Here he works as a scientific officer for the first time on nuclear physics. He is than promoted to senior scientific officer. In 1941 accepts a position as officer in charge of the Atomic Nucleus Laboratory.

Ilja Frank becomes a senior scientific officer in Professor A.N. Terenin's laboratory in the State Optical Institute in Leningrad. Here he investigates in photoluminescence and in photochemistry. He writes also here his first publication with Vavilov on luminescence. The work he carries out in these years serves later as basis of his doctoral dissertation in 1935.

Ilja Frank is appointed professor and becomes head of the department of physics at the University of Moscow. He works there till his death. His laboratory is involved in the (at that time secret) study of nuclear reactors. In particular, they study the diffusion and thermalization of neutrons. Frank works also on gamma rays, physical optics, the investigation of reactions on light nuclei and nuclear fission by mesons.

Frank and Tamm provide the theoretical explanation of Cherenkov radiation, an effect in which light is emitted when charged particles travel through an optically transparent medium at speeds greater than the speed of light in that medium. The amount of energy radiated in this process is given by the Frank–Tamm formula. This discovery leads to the development of new methods for detecting and measuring the velocity of high-speed particles, and is of great importance for nuclear physics research.

Ilja Frank is born in Leningrad as younger son of Mikhail Lyudvigovich Frank, a brilliant mathematician of Jewish origin, and of Yelizaveta Mikhailovna Gratsianova, a Russian Orthodox physician.

Ilja Frank attends Moscow State University. Here he studies mathematics and theoretical physics. Starting from his second year he works in the laboratory of Sergey Ivanovich Vavilov.

1