Oleg Firsov
Encyclopedia
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
-theorist known for his work on atomic interaction. He was awarded the Lenin Prize
Lenin Prize
The Lenin Prize was one of the most prestigious awards of the USSR, presented to individuals for accomplishments relating to science, literature, arts, architecture, and technology. It was created on June 23, 1925 and was awarded until 1934. During the period from 1935 to 1956, the Lenin Prize was...
in 1972 for a series of work titled "Elementary processes and non-elastic scattering at nuclear collisions".
Biography
Firsov was the son of Boris Nilovich Firsov (1888–1920), one of the first Russian pilots, and Olga Vladimirovna von Walden (by mother Golitsyn, 1892–1920). He lost his parents at the age of 4, and grew up in an orphanageOrphanage
An orphanage is a residential institution devoted to the care of orphans – children whose parents are deceased or otherwise unable or unwilling to care for them...
.
He graduated with an undergraduate degree in physics from Leningrad State University in 1938, and remained there until the end of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. Staying in the city, he then moved to the Ioffe Physico-Technical Institute
Ioffe Physico-Technical Institute
Ioffe Physical-Technical Institute of the Russian Academy of Sciences is one of Russia's largest research centers specialized in physics and technology. The institute was established in 1918 in Petrograd and run for several decades by Abram Fedorovich Ioffe...
in Leningrad
Saint Petersburg
Saint Petersburg is a city and a federal subject of Russia located on the Neva River at the head of the Gulf of Finland on the Baltic Sea...
, where he obtained his PhD
PHD
PHD may refer to:*Ph.D., a doctorate of philosophy*Ph.D. , a 1980s British group*PHD finger, a protein sequence*PHD Mountain Software, an outdoor clothing and equipment company*PhD Docbook renderer, an XML renderer...
in 1947 under Yakov Frenkel
Yakov Frenkel
Yakov Il'ich Frenkel, was a Soviet physicist renowned for his works in the field of solid-state physics. He is also known as Jacov Frenkel....
's supervision. In 1955, he was invited by Igor Kurchatov
Igor Kurchatov
Igor Vasilyevich Kurchatov , was a Soviet nuclear physicist who is widely known as the director of the Soviet atomic bomb project. Along with Georgy Flyorov and Andrei Sakharov, Kurchatov is widely remembered and dubbed as the "father of the Soviet atomic bomb" for his directorial role in the...
to Moscow
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...
. He joined the Kurchatov Institute of Atomic Energy where worked until 1994, when he became severely ill.
He was married to the physicist Victoria Yevgenyevna Lichko (1915–2004). Their daughter is the composer
Composer
A composer is a person who creates music, either by musical notation or oral tradition, for interpretation and performance, or through direct manipulation of sonic material through electronic media...
Elena Firsova
Elena Firsova
Elena Olegovna Firsova is a Russian composer.-Life:She was born in Leningrad into the family of physicists Oleg Firsov and Viktoria Lichko. She studied music in Moscow with Alexander Pirumov, Yuri Kholopov, Edison Denisov and Philip Herschkowitz...
(b. 1950).
Work
Firsov is known among physicists for his studies of the quasi-molecular approach in the quantum mechanical
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...
theory of atomic collisions. In a 1951 paper, he presented an elegant analytical solution to the complicated problem of resonant charge exchange during hydrogen-hydrogen collisions. Since then, the quasi-molecular approach has been used in many other fields related to the physics of atomic collisions.
In 1953, Firsov devised the solution to the so-called inverse collision problem in which a scattering potential is inferred from known values of the scattering cross-section.
At the beginning of the 1950s, when work on controlled fusion reactions had just started at Kurchatov, solving the problem of charge exchange for the confinement of a plasma in a magnetic system was crucial. Accordingly, Firsov was invited to tackle the problem. Applying his gift for discerning the root of a problem, he considered plasma permeation through a picket fence magnetic system and, in 1957, was the first to theoretically determine the width of a magnetic gap for a cusp system. His approach is still used.
Around the same time, Firsov also carried out two of his best-known works. In 1957, he found the exact upper and lower limits of the interaction potential between two atoms in the Thomas-Fermi approximation. Since these limits turned out to be close to each other, the potential could be determined accurately. Firsov suggested a simple approximation of this potential that is convenient to use and is now referred to as the Firsov potential. In 1959, he proposed a formula for inelastic energy losses in an atomic collision on the basis of a very clear physical picture in which a number of electrons are exchanged between the colliding atoms. This formula has not only found a wide range of application in the physics of ion beams and radiation effects, but has also stimulated considerable theoretical activity.
In 1966 and 1970, Firsov published two papers on the reflection of particles from a solid surface.
During the last few years of his life, Firsov investigated one of the most fundamental cosmological problems-identifying the nature of dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...
. He proposed that the invisible mass in the universe is dust of ordinary matter.
Among his pupils were physicists Mikhail Chibisov, Yuri Martynenko, Boris Smirnov and Edward Lozansky. He had particularly close scientific links with the experimentalist
Experimentalist
"Experimentalist" is a blanket term for all sorts of scientists engaged more in experimental activity than in the theoretical side of their sciences....
Vera Yurasova
Vera Yurasova
Vera Yurasova is a Russian physicist who has made major contributions to the study of the processes of interactions between ion beams and solid surfaces, both their experimental characteristics and their physical mechanisms....
, with whom he also worked in the Russian Academy of Sciences
Russian Academy of Sciences
The Russian Academy of Sciences consists of the national academy of Russia and a network of scientific research institutes from across the Russian Federation as well as auxiliary scientific and social units like libraries, publishers and hospitals....
Council for Plasma Physics.
Inverse collision problem
Let us consider the scatteringScattering
Scattering is a general physical process where some forms of radiation, such as light, sound, or moving particles, are forced to deviate from a straight trajectory by one or more localized non-uniformities in the medium through which they pass. In conventional use, this also includes deviation of...
of particles with energy
in a repulsive field 
and introduce the quantity
Firsov proved that this quantity is implicitly related to the angle of scattering
(
is the impact parameterImpact parameter
The impact parameter b is defined as the perpendicular distance between the path of a projectile and the center of the field U created by an object that the projectile is approaching...
) by the formula
