Dissertation committee:
Dr. Emmanuel M. Xilouris - National Observatory of Athens
Prof. Dr. Nektarios Vlahakis - University of Athens
Prof. Dr. Despina Hatzidimitriou - University of Athens
Dr. Alceste Z. Bonanos - National Observatory of Athens
Prof. Dr. Kalliopi Dasyra - University of Athens
Prof. Dr. Apostolos Mastichiadis - University of Athens
Prof. Dr. Maarten Baes - University of Ghent
Summary:
The present thesis is investigating the properties of cosmic dust and its interaction with the stellar radiation field (originating from different stellar populations) on global scales, for 814 galaxies in the local Universe, all observed by the Herschel Space Observatory. I took advantage of the widely used fitting code CIGALE, properly adapted to include the state-of-the-art dust model THEMIS. Using the DustPedia photometry I have determined the physical properties of the galaxies, such as the dust and stellar mass, the star-formation rate, the bolometric luminosity, the unattenuated and the absorbed by dust stellar light, for both the old (> 200 Myr) and young (< 200 Myr) stellar populations.
In addition, one of the main goals of this thesis, was to construct detailed 3D dust
radiative transfer models for spatially resolved, nearby galaxies. From 2D images I have derived the 3D distributions of stars and dust. To model the complex geometries, I have used SKIRT, a state-of-the-art 3D Monte Carlo radiative transfer code designed
to self-consistently simulate the absorption, scattering, and thermal re-emission by the dust for arbitrary 3D distributions. By analysing the contribution of the different stellar populations to the radiative dust heating processes in four nearby face-on barred galaxies: NGC1365, M83, M95, and M100; and a galaxy hosting an AGN: NGC1068, has enabled me to quantify the fraction directly related to star-formation, as well as the extent of the contribution of the AGN to the diffuse dust heating in three dimensions.
Keywords:
radiative transfer, ISM: dust, extinction, galaxies: individual: M83, M95, M100, NGC1068, NGC1365, galaxies: photometry, galaxies: ISM, galaxies: evolution, infrared: galaxies, infrared: ISM
