Observations and modeling of massive protostars in the framework of the Herschel Space Observatory

Today the formation of massive stars is still not well understood due to the huge interaction of these objects with their environment, leading to a theoretical limit in the final mass that observations contradict. The future observatories, like the Herschel Space Observatory, will try to answer some of the questions linked to this topic, particularly through the water line emissions. The correct and precise analysis of the future data is then necessary and needs a full work linking the observations and the modelling of the objects that will be studied. Hence the main goal of this PhD Thesis was to elaborate a robust and global modeling method of the massive dense cores in which high-mass stars are forming. The method leaded to a physical description and a chemical study of multiple massive dense cores, opening new views on evolution aspects. In addition it gave some tweaks on the guaranteed-time key program WISH for the water line emissions and confirmed the key role of this molecule for a better understanding of the high-mass star formation. (author)