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Information × Registration Number 0212U001601, 0107U002279 , R & D reports Title Physical characteristics and galaxy evolution: comparative studies of the stellar population and interstellar medium properties popup.stage_title Head Izotov Yu.I., Registration Date 14-02-2012 Organization Main Astronomical Observatory popup.description2 Using new atomic data we derived the primordial helium abundance. These data suggest that the number of neutrino species can be greater than three and that the primordial nucleosynthesis was non-standard. Using observations in the optical, near- and mid-infrared ranges we derived chemical composition of a large sample of galaxies. Several galaxies with low oxygen abundances were discovered. The characteristics of the interstellar medium in these galaxies are similar to those in high-redshift galaxies. This opens the opportunity to study physical conditions in galaxies on the stage of their formation. It is shown that dwarf galaxies now are still on the stage of appreciable enrichment by heavy elements, while the heavy element enrichment of bigger galaxies is slower. We constructed the luminosity-metallicity relation for the galaxies with active star formation and showed that this relation is the same for the nearby and distant galaxies. We studied the physical conditions in one galaxy with the gamma-ray burst. We found and studied 5 dwarf galaxies with active nuclei. These objects are the first known galaxies with the low chemical abundances which with high probability contain supermassive black holes. For the first time we also found and studied low-metallicity luminous blue variable stars with powerful stellar wind which efficiently enrich the interstellar medium by heavy elements. For the first time we discovered a supernova with coronal emission lines in the dwarf galaxy. We studied several hundred dwarf galaxies containing large populations of massive star with the stellar wind. The model of halo formation in the spiral galaxy M33 by merging of individual fragments was build. The stellar populations in the extremely metal-poor galaxy I Zw 18 were studied using observations with the Hubble Space Telescope. Product Description popup.authors Ізотов Юрій Іванович Агієнко Катерина Борисівна Гусєва Наталія Григорівна Зінченко І.О. Никитюк Тетяна Вікторівна Пілюгін Леонід Степанович Якобчук Тарас Миколайович popup.nrat_date 2020-04-02 Close