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Information × Registration Number 0210U004063, 0107U002679 , R & D reports Title An invstigation of the stellar population characteristics and interstellar medium of the local part of the Galactic disc. popup.stage_title Head Andrievsky S.M., Registration Date 11-02-2010 Organization Odessa I.I.Mechnikov university popup.description2 Object of investigation - classical Cepheids, s-Cepheids, W Vir type stars, RR Lyr type stars, variable stars of Lambda Boo type. The aim of the work - elaboration and improvement of the spectroscopic methods for determination of the high-accuracy atmosphere parameters, metallicity, luminosity, normal color indices and color excesses of Cepheids of the different types and stationary supergiants for their following application for the atmosphere models specification and study of the elemental abundance, absorbing matter distribution in our Galaxy, the comprehensive investigation of the variability of the pulsating star characteristics as a function of the pulsation phase, that is very important for the theoretical calculations of the stellar evolution and stellar pulsations. Results of this work were obtained using the modern methods of the stellar atmospheres diagnostics (atmosphere models and synthetic spectra technique) basing on the original observations performed with the help of electrophotometres of the new generation and high-resolution spectrographs. With the help of elaborated methods we determined high-accuracy atmosphere parameters and metallicity (Teff, lоg g, Vt, [Fe/H]) for 74 non-variable F-, G-, K- supergiants and 164 classical Cepheids on 675 pulsation phases. 28 relations between MV, Teff and line depth ratios Rlambda, were established, and then they were used to estimate absolute magnitudes MV for 56 F-, G-, K- supergiants (accuracy is about 0.m05-0.m30). 8 cool giants of the globular cluster NGC 6388 and very distant star of W Vir type QQ Per were studied. For the eight s-Cepheids an investigation of the parameter variation with pulsational phase was carried out. Results of this work are included in the publications (papers, conference proceedings), used for the preparation of the PhD and ScD theses, and for the scientific researches in other observatories, Product Description popup.authors Ковтюх В.В. Усенко І.О. popup.nrat_date 2020-04-02 Close