Lyubimkov Leonid Sergeyevich General data:
Born: 15.11.1843
Place of birth: Vologda city, Vologda region, Russian SSR
Studied in: M. V. Lomonosov Moscow State University (1965);
Key interests: physics of variable stars, astrophysics, AGNs. PhD Thesis: Some methods of studying stellar atmospheres and their application to estimate helium content (1977 ); ScD Thesis: Investigation of the chemical composition of stars of spectral types B-G by the method of atmospheric models (1988 );
Biography:
He was born on November 15, 1943 in the Vologda city of Vologda region of the Russian SSR.
In 1965 he graduated from M. V. Lomonosov Moscow State University. According to other sources, he was a student of the Leningrad Order of Lenin of the AA Zhdanov State University during 1960-1965.
During 1965-1968 he was a graduate student of the Department of Astrophysics of the A. A. Zhdanov Leningrad Order of Lenin of the State University. Academician V. V. Sobolev was his scientific supervisor.
Since 1969 he has been an employee of the Crimean Astrophysical Observatory. Starting from the position of a junior researcher, he worked as a head of the laboratory of stellar evolution of the Department of Stellar Physics.
In 1977 he defended his dissertation "Some methods of studying stellar atmospheres and their application to assess the helium content".
In 1989 he defended his doctoral dissertation on "Investigation of the chemical composition of stars of spectral types B-G by atmospheric models" for the degree of Doctor of Physical and Mathematical Sciences in "Astrophysics, Radio Astronomy" (at that time the name of the specialty was formulated as "Astrophysics and stellar astronomy").
He is an expert in the field of chemical composition of stars. He studied the physical parameters and chemical composition of hundreds of stars in a wide range of spectral types from O to K. Along with normal stars, he studied chemically peculiar stars of the types Ap, Am, δ Set, HgMn and others. He discovered the following phenomena: 1) empirical evidence of early mixing in fairly massive stars at the first and longest stage of their evolution - the main sequence stage, which became one of the incentives to build models of stars with rotation as a source of mixing; 2) the observed excess of sodium in the atmospheres of F- and G-supergiants as evidence of the theory of NeNa-cycle; 3) the early appearance in the shell of the famous Supernova 1987A products of explosive fusion, found from the analysis of ultraviolet spectra obtained at the space station "Astron". He was the initiator of two major international projects, which were conducted for about 20 years in 1996-2016 jointly by the Crimean Astrophysical Observatory and the MacDonald Observatory of the University of Texas. These projects received a number of international grants, including the Chretien Grant of the American Astronomical Society in 1997.
He studied the stars in two successive stages of evolution - the B-stars of the main sequence and the next stage of supergiants and giants of types A-K. According to the high-resolution spectra obtained with his participation at the MacDonald Observatory and the Crimean Astrophysical Observatory, he determined with high accuracy the fundamental parameters of about 200 stars of both types, and studied their chemical composition. The main focus was on evolutionary changes in the contents of light elements, which play a key role in stellar evolution. He discovered a number of new effects related to evolutionary changes in the content of elements such as lithium, carbon, nitrogen and oxygen. By comparison with models of rotating stars, he explained the quantitatively known anticorrelation of "nitrogen-carbon" in the late giants and supergiants, as well as the lack of lithium in most such stars.
L.S. Lyubimkov discovered a systematic evolutionary enrichment of the atmospheres of massive stars with helium and nitrogen, which required a significant revision of the theory of stellar evolution.
He has published about 130 scientific papers.
Main publications:
1. Lyubimkov L. S., Lambert D. L., Rachkovskaya T.M., et al. Surface abundances OF EARLY B-type stars. I. Spectral observations of 123 stars; measurements of hydrogen and helium lines; infrared photometry // Mon. Notic. Roy. Astron. Soc. - 2000.- 316.- P.19
2. Lyubimkov L. S., Rachkovskaya R.T., Rostopchin S. I., Lambert D.L. Surface abundances of light elements for a large sample of early B-type stars // Mon. Notic. Roy. Astron. Soc. - 2002.- 333.- P.9
3. Lyubimkov Leonid S., Lambert David L., Korotin Sergey A., Poklad Dmitry B., Rachkovskaya Tamara M., Rostopchin Sergey I. Nitrogen enrichment in atmospheres of A- and F-type supergiants // Monthly Notices of the Royal Astronomical Society, 2011, Volume 410, Issue 3, pp. 1774-1786.
4. Carbon abundance and the N/C ratio in atmospheres of A-, F- and G-type supergiants and bright giants / Lyubimkov Leonid S., Lambert David L., Korotin Sergey A., Rachkovskaya Tamara M., Poklad Dmitry B. // Monthly Notices of the Royal Astronomical Society, Volume 446, Issue 4, p.3447-3460
Sources:
1 Pavlenko Ya. V., Vavilova I. B., Kostiuk Ò. Astronomy in Ukraine. Organizations and strategies in astronomy. — Springer-Verlag, 2005.—Vol. 6.—P. 22
2 Àñòðîíîìû Ðîññèè 1917-2017/ íàó÷. ðåä. À.Ì.×åðåïàùóê, Êàçàíü, Êàçàí. ôåä. óí-ò, 2017.- 568ñ- C.282
3 Êðûìñêàÿ àñòðîôèçè÷åñêàÿ îáñåðâàòîðèÿ.Îòêðûòèÿ, ñäåëàííûå â îáñåðâàòîðèè
