Georgy Timofeyevich Zatsepin (russian: Гео́ргий Тимофе́евич Заце́пин; – 8 March 2010) was a

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...

and

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eig ...

n astrophysicist known for his works in

cosmic ray Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our own ...

physics and

neutrino A neutrino ( ; denoted by the Greek letter ) is a fermion (an elementary particle with spin of ) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass ...

astrophysics.

Biography

He was born in

Moscow Moscow ( , US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the capital and largest city of Russia. The city stands on the Moskva River in Central Russia, with a population estimated at 13.0 millio ...

. Zatsepin graduated from the

Faculty of Physics Faculty may refer to: * Faculty (academic staff), the academic staff of a university (North American usage) * Faculty (division), a division within a university (usage outside of the United States) * Faculty (instrument), an instrument or warra ...

of the

Moscow State University M. V. Lomonosov Moscow State University (MSU; russian: Московский государственный университет имени М. В. Ломоносова) is a public research university in Moscow, Russia and the most prestigious ...

in 1941 and worked for three years at an aircraft building plant in

and later in Irkutsk. He entered

aspirantura Candidate of Sciences (russian: кандидат наук, translit=kandidat nauk) is the first of two doctoral level scientific degrees in Russia and the Commonwealth of Independent States. It is formally classified as UNESCO's International Stan ...

of the faculty in 1944 and six years later defended dissertation "Density spectrum of Extensive Air Showers" for

Candidate of Sciences Candidate of Sciences (russian: кандидат наук, translit=kandidat nauk) is the first of two doctoral level scientific degrees in Russia and the Commonwealth of Independent States. It is formally classified as UNESCO's ISCED level 8, "d ...

degree. Prior to this, in 1947-1949 he developed methods of studying and using experimental data discovered, that they are based on nuclear cascade process, with

electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no ...

photon A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless, so they a ...

processes being secondary. Since 1950 he works as senior research assistant at the

Lebedev Physical Institute The Lebedev Physical Institute of the Russian Academy of Sciences (LPI RAS or just LPI) (in russian: Физи́ческий институ́т имени П.Н.Ле́бедева Российской академии наук (ФИАН)), situated ...

. In 1951 he was awarded the

Stalin Prize Stalin Prize may refer to: * The State Stalin Prize in science and engineering and in arts, awarded 1941 to 1954, later known as the USSR State Prize The USSR State Prize (russian: links=no, Государственная премия СССР, ...

for discovering the nuclear cascade process. He defended dissertation "Nuclear-cascade process and EAS" for

Doctor of Sciences Doctor of Sciences ( rus, доктор наук, p=ˈdoktər nɐˈuk, abbreviated д-р наук or д. н.; uk, доктор наук; bg, доктор на науките; be, доктар навук) is a higher doctoral degree in the Russi ...

degree in 1954 and became professor in 1958. In the 1960s Zatsepin predicted

Greisen–Zatsepin–Kuzmin limit The Greisen–Zatsepin–Kuzmin limit (GZK limit or GZK cutoff) is a theoretical upper limit on the energy of cosmic ray protons traveling from other galaxies through the intergalactic medium to our galaxy. The limit is (50 EeV), or about 8 j ...

. In the same period he begin research of muons and

s laying foundations of neutrino astronomy and neutrino astrophysics. At the neutrino laboratory created by him in Lebedev Physical Institute methods of

solar neutrino A solar neutrino is a neutrino originating from nuclear fusion in the Sun's core, and is the most common type of neutrino passing through any source observed on Earth at any particular moment. Neutrinos are elementary particles with extremely smal ...

detection were developed. He became Corresponding Member of the

Academy of Sciences of the Soviet Union The Academy of Sciences of the Soviet Union was the highest scientific institution of the Soviet Union from 1925 to 1991, uniting the country's leading scientists, subordinated directly to the Council of Ministers of the Soviet Union (until 1946 ...

in 1968 and Full Member in 1981. In 1982 Zatsepin was awarded Lenin Prize for creating Station of Cosmic Rays of the Yakut Scientific-Research Base of the Academy of Sciences of the Soviet Union. For creating the

Baksan Neutrino Observatory The Baksan Neutrino Observatory (BNO; Baksan is sometimes spelled Baxan) is a scientific laboratory of INR RAS located in the Baksan River gorge in the Caucasus mountains in Russia. Cleared for building in 1967, it started operations in 1977, bec ...

, and conducting experiments there he was awarded the State Prize of the Russian Federation in 1998. Zatsepin was also awarded the

Order of the Red Banner of Labour The Order of the Red Banner of Labour (russian: Орден Трудового Красного Знамени, translit=Orden Trudovogo Krasnogo Znameni) was an order of the Soviet Union established to honour great deeds and services to th ...

in 1975 and 1981,

Order of the October Revolution The Order of the October Revolution (russian: Орден Октябрьской Революции, ''Orden Oktyabr'skoy Revolyutsii'') was instituted on October 31, 1967, in time for the 50th anniversary of the October Revolution. It was conferr ...

in 1987. Until 2006 was the chairman of the Cosmic Rays and Space Physics Chair of the MSU Skobeltsyn Institute of Nuclear Physics. He died in Moscow on 8 March 2010, aged 92.

Sources

Georgy Zatsepin
at the

Institute for Nuclear Research Institute for Nuclear Research of the Russian Academy of Sciences (INR RAS, russian: Институт ядерных исследований) is a Russian scientific research center "for further development of the experimental base and fundament ...

of the

Russian Academy of Sciences The Russian Academy of Sciences (RAS; russian: Росси́йская акаде́мия нау́к (РАН) ''Rossíyskaya akadémiya naúk'') consists of the national academy of Russia; a network of scientific research institutes from across ...

References

1917 births 2010 deaths 20th-century Russian physicists Scientists from Moscow Full Members of the Russian Academy of Sciences Full Members of the USSR Academy of Sciences Academic staff of the Moscow Institute of Physics and Technology Moscow State University alumni Stalin Prize winners Lenin Prize winners Recipients of the Order "For Merit to the Fatherland", 4th class Recipients of the Order of Honour (Russia) Recipients of the Order of the Red Banner of Labour State Prize of the Russian Federation laureates Cosmic ray physicists Russian astrophysicists Soviet astrophysicists Burials in Troyekurovskoye Cemetery {{Russia-physicist-stub