Alexander Yevgenyevich Chudakov

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Aleksandr Chudakov ( Russian : Александр Евгеньевич Чудаков ., Scientific transliteration : Aleksandr Evgen'evič Čudakov , English transcription: Aleksandr Evgen'evich Chudakov, * 16th June 1921 in Moscow ; † 25. January 2001 ) was a Russian physicist who experimentally on the Field of cosmic rays worked.

Live and act

Tschudakow was born as the son of the engineer and scientist Yevgeny Alexejewitsch Tschudakow (1890-1953). After graduating from school, he studied physics from 1939 at Lomonossow University in Moscow. Interrupted by the Second World War, he was only able to complete his studies in 1948. As early as 1946 he worked at the Lebedev Institute of the Soviet Academy of Sciences , more precisely in the group that dealt with the measurement of cosmic rays. From 1947 to 1951 he measured the intensity of cosmic rays above the earth's atmosphere in a series of rocket experiments . With a thesis on the evaluation of these experiments, he received his doctorate in 1953 as a candidate for science . In 1949 he understood that the mutual shielding of the fields of an electron and a positron leads to reduced ionization of a high-energy electron-positron pair. This phenomenon is now known as the Chudakov effect (or King Perkins Chudakov effect). It also occurs in quantum chromodynamics when the color charge of two nearby quarks or gluons is shielded, and there it is referred to as "color transparency".

From 1953, Chudakov investigated Cherenkov radiation from air showers . During the preparation of this experiment, he experimentally demonstrated the transition radiation predicted in 1945 by Witali Ginsburg and Ilja Frank . From 1957 to 1960, Tschudakow developed the first water calorimeter to detect Cherenkov radiation. It contained 100 tons of water and can be considered the forerunner of modern Cherenkov water detectors like Super-Kamiokande . In 1961, Tschudakow and Georgi Sazepin suggested using Cherenkov radiation from atmospheric showers to search for sources of high-energy gamma radiation (around 1 TeV ), thereby helping to establish gamma astronomy . Tschudakow designed the first Cherenkov gamma-ray telescope, which ran from 1960 to 1963 in Katsiveli on the Crimea peninsula , but could not detect any gamma radiation sources.

After the start of the first Sputnik in 1957, a new way of studying cosmic rays opened up and Chudakov returned to this research area. In 1960 he and Sergei Nikolajewitsch Wernow received the Lenin Prize for “the discovery and investigation of the outer radiation belt around the earth” (known as the Van Allen Belt ) for a series of works in this area . With a thesis on this subject, he received his doctorate in 1959 as a "Doctor of Physical and Mathematical Sciences" (corresponds to the German habilitation ). From 1963, Chudakov worked on the preparation for the underground Baksan neutrino observatory to study cosmic muons and neutrinos . This scintillation telescope went into operation in 1978 and set upper limits for neutrino oscillations , which for a long time remained the best in the world. After adapting the design, it looked for the hypothetical proton decay and also set a new limit of 1.25 · 10 30 years for neutrinoless decay channels , which was soon improved by other groups. The limits for the search for super-heavy magnetic monopoles and neutrinos from Neutralino - Annihilation were also set by the Baksan Neutrino Observatory.

Even before Eugene N. Parker, Tschudakow provided an estimate for the upper limit of the flux of magnetic monopoles on the basis of astrophysical arguments, so that the “Parker limit” should actually be called the “Chudakov-Parker limit”. From 1971 Chudakov worked for the Institute for Nuclear Research of the Soviet Academy of Sciences, which was spun off from the Lebedev Institute. He led the Kover experiment , which examined air showers from 1974. He was also the first to propose Lake Baikal in the mid-1960s to build an underwater muon detector. Based on this idea, the underwater neutrino telescope NT-200 was built there. Even his idea of ​​measuring Cherenkov light reflected by snow from air showers with airplanes was not realized by himself.

Chudakov had been a corresponding member of the Soviet Academy of Sciences since 1966, and a full member since 1987, and was also a member of its presidium. He received the Lenin Prize and the State Prize. He was secretary and later chairman of the Cosmic Rays Commission of the International Union for Pure and Applied Physics . For twenty years he headed the Scientific Committee on Cosmic Rays of the Russian Academy of Sciences. From the 1950s he taught experimental nuclear physics at Lomonossow University in Moscow.

Chudakov was married and had two children.

literature

  • GV Domogatskii, GT Zatzepin, AS Lidvanskii, VA Matveev and Yu. I. Stozhkov: In memory of Aleksandr Evgen'evich Chudakov. In: Physics Uspekhi. Volume 44, No. 5, 2001, pp. 547-548, doi : 10.1070 / PU2001v044n05ABEH000961 (with picture)
  • CERN Courier. April 2, 2001, p. 3 (with picture, digital copy , pdf )
  • AS Lidvansky: AE Chudakov. In: CosNews. Cosmic Ray News Bulletin. No. 45, summer 2001, digitized
  • Prominent personalities in the USSR. Scarecrow Press, Metuchen, New Jersey 1968, p. 113
  • GV Domogatskii, GT Zatsepin, MA Markov, VA Matveev and GB Khristiansen: Aleksandr Evgen'evich Chudakov (on his seventieth birthday). In: Soviet Physics Uspekhi. Volume 34, No. 7, 1991, pp. 637-638, doi : 10.1070 / PU1991v034n07ABEH002457 (with picture)
  • SN Vernov, GV Domogatskii, GT Zatsepin and MA Markov: Aleksandr Evgen'evich Chudakov (on his sixtieth birthday). In: Soviet Physics Uspekhi. Volume 24, No. 7, 1981, pp. 641–644, doi : 10.1070 / PU1981v024n07ABEH004877 (with picture)

Web links

Individual evidence

  1. ↑ on Evgeni Alexejewitsch Tschudakow see: Great Soviet Encyclopedia. Volume 29, 1982, p. 190 ( digitized version ); Encyclopedia of Russia and the Soviet Union. McGraw-Hill, New York [et. a.] 1961, p. 95; Alex G. Cummins: Chudakov, Evgeny Alekseevich. In: The Supplement to the Modern Encyclopedia of Russian, Soviet and Eurasian History. Volume 6, Academic International Press, Gulf Breece 2005, ISBN 0-87569-142-0 , pp. 75-77; Photo of the grave of Yevgeny Alexejewitsch Tschudakow ( Memento from July 14, 2012 in the web archive archive.today )
  2. ↑ Aleksandr E. Chudakov: On an Ionization Effect Related to the Observation of Electron-Positron Pairs at very high Energies. In: Bulletin of the Academy of Sciences of the USSR. Physical Series. Volume 19, No. 6, 1955, pp. 589-595
  3. ↑ after Don Perkins, who found the effect experimentally without knowing about Tschudakov's work. Perkins refers to suggestions from David T. King, cf. DH Perkins: Ionization at the Origin of Electron Pairs, and the Lifetime of the Neutral Pion. In: The Philosophical Magazine. Series 7, Vol. 46, 1955, pp. 1146-1148; Don Perkins: Observing the Chudakov Effect. In: CERN Courier. May 21, 2008 ( digitized version )
  4. ↑ Nikolai N. Nikolaev and Bronislav G. Zakharov: Color Transparency and Scaling Properties of Nuclear Shadowing in Deep Inelastic Scattering. In: Journal of Physics. Series C, Volume 49, 1991, pp. 607-618, doi : 10.1007 / BF01483577 .
  5. ↑ GT Zatsepin and AE Chudakov: Method of Finding Local Sources of high-energy photon. In: Soviet Physics JETP. Volume 14, 1962, pp. 469-470
  6. ↑ AS Lidvansky: Air Cherenkov Methods in Cosmic Rays: A Review and Some History. In: Radiation Physics and Chemistry. Volume 75, No. 8, August 2006, pp. 891–898, doi : 10.1016 / j.radphyschem.2005.12.019 , preprint on arxiv.org (with image of Tschudakov's Cherenkov gamma-ray telescope in Katsiveli)
  7. ↑ on Sergei Nikolajewitsch Wernow see obituary for Sergei Nikolaevich Vernov by IB Teplov and AE Chudakov (English, with picture) ( Memento from October 29, 2012 in the Internet Archive )
  8. ^ Russia Takes Credit For Van Allen Belts. In: New York Times . April 22, 1960
  9. ↑ MM Boliev, AV Butkevich, VN Zakidyshev, BA Makoev, SP Mikheev and AE Chudakov: Restrictions on Neutrino Oscillations Parameters using Data from the Baksan Underground Telescope. In: Soviet Journal of Nuclear Physics. Volume 34, 1981, pp. 787-788
  10. ↑ EN Alekseev et al .: Lower Limit on the Proton Lifetime According to Data from the Baksan Underground Scintillation Telescope. In: JETP Letters. Volume 33, 1981, pp. 651-653
  11. ↑ MM Boliev, EV Bugaev, AV Butkevich, AE Chudakov, SP Mikheev, OV Suvorova and VN Zakidyshev: Search for Supersymmetric Dark Matter with Baksan Underground Telescope. In: Nuclear Physics B Proceedings Supplement. Volume 48, 1996, pp. 83-86, doi : 10.1016 / 0920-5632 (96) 00214-9
  12. ↑ GV Domogatsky and IM Zhelesnykh: The hot Universe model and the problem of the Dirac monopoles. In: Soviet Journal of Nuclear Physics. Volume 10, 1970, pp. 702-704
  13. ↑ EN Parker: The Origin of Magnetic Fields. In: Astrophysical Journal . Volume 160, 1970, pp. 383-404, doi : 10.1086 / 150442 ; EN Parker: The Generation of Magnetic Fields in Astrophysical Bodies. II. The Galactic Field. In: Astrophysical Journal. Volume 163, 1971, pp. 255-278, doi : 10.1086 / 150765 ; EN Parker: The Generation of Magnetic Fields in Astrophysical Bodies. VI. Periodic Modes of the Galactic Field. In: Astrophysical Journal. Volume 166, 1971, pp. 295-300, doi : 10.1086 / 150958 ; MS Turner, EN Parker and T. Bogdan: Magnetic Monopoles and the Survival of Galactic Magnetic Fields. In: Physical Review. Series D, Volume 26, 1982, pp. 1296-1305, doi : 10.1103 / PhysRevD.26.1296
personal data
SURNAME Tschudakow, Alexander Evgenjewitsch
ALTERNATIVE NAMES Чудаков, Александр Евгеньевич (Russian); Čudakov, Aleksandr Evgenʹevič (scientific transliteration); Chudakov, Aleksandr Evgen'evich (English transcription)
BRIEF DESCRIPTION Russian physicist
DATE OF BIRTH June 16, 1921
PLACE OF BIRTH Moscow
DATE OF DEATH January 25, 2001