Mozgova A. Material composition of meteors by remote spectral observations

The thesis is devoted to the study of photographic spectra of bright meteors obtained with the help of an optical prism (October 21 and 22, 1958 and August 10, 1965) and a diffraction grating (August 2 and 27, 2011, February 20 and August 11, 2012). The main result is the material composition of the investigated meteor bodies is determined. The most intensive lines in the meteor spectra belong to the CrI, FeI, MgI, SiI, AlI, MnI, CaI, TiI, NaI atoms and FeII, CaII, MgII, TiII, SiII ions, which are characteristic of iron and iron-silicate meteoroids. A catalog of the observed emission lines in the spectrum of each meteor and catalog of spectral lines of the iron FeI and FeII and magnesium MgI and MgII multiplets (352 lines) were created. The Grotrian diagrams for spectral lines of multiplets of iron and magnesium, illustrating the transitions between electronic states in atoms, were constructed. In the approximation of the thermodynamic equilibrium state and the Boltzmann distribution of energy level population, an effective temperature of the excited states of neutral iron FeI and the number of radiating atoms of FeI in the meteor coma were determined from the August 2, 2011 meteor spectrum. A nonlinear change in the meteoric coma temperature with a height and over time has been detected. This is a sign of the destruction of the meteoric body during outburst with subsequent release of the substance. The practical value of this work is that the data obtained as a result of the processing of the meteoric spectra presented in the work are valuable for fundamental research of physical and chemical properties of meteors matter. The catalog of spectral multiplets lines of chemical elements and the Grotrian diagrams presented in the work can be used by researchers to study meteoric phenomena. The data of the meteors chemical composition are important for resolving cosmogony questions and chemical evolution of the Solar system. Key words: meteors, meteoroids, spectra, remote aerospace researches, multiplets, Grotrian diagrams.