Skip to Main content Skip to Navigation

Etude multi-longueur d'onde des galaxies lumineuses en infrarouge locales

Abstract : This thesis deals with a panchromatic study of luminous infrared galaxies (LIRGs) detected at 15 microns by ISOCAM (camera aboard ISO) and at 24 microns by MIPS ( camera aboard the recently launched Spitzer satellite). These galaxies are today considered to be the Rosetta Stone of galaxy evolution since they are found to be far more numerous at high redshift and it is thought that a large part of stars seen in the local universe are born in such phases.
The first part of this thesis presents a new study dedicated to dust emission of distant LIRGs in the mid-infrared range. Their dust emission has been compared to those of a local sample of LIRGs in addition to the prediction of several spectral energy distributions (SEDs) built on data available in the local universe.It has been shown that distant and local LIRGs present similar mid infrared spectral energy distribution : similar PAH bumps are detected in both local and distant LIRGs, however distant LIRGs show evidence of a stronger silicate absorption at 10 microns associated silicate grains. It also shows that distant LIRG mid infrared emission can be used together with local SEDs in order to estimate the total infrared luminosity.
The second part of this thesis is dedicated to the burst of star formation and to the recent star formation history of these galaxies, which is responsible for the dust emission. This study was done thanks to a combination of high resolution spectra (R=2000 in the rest frame) obtained at VLT/FORS2 and the stellar population synthesis models called GALAXEV (Bruzual \& Charlot, 2003). It has been shown that the burst of star formation has a duration of about 0.1 Gyear. 10 \% of the stellar content is formed during this burst of star formation.
Complete list of metadatas
Contributor : Delphine Marcillac <>
Submitted on : Friday, July 31, 2009 - 2:38:48 PM
Last modification on : Monday, February 10, 2020 - 6:12:35 PM
Long-term archiving on: : Tuesday, June 15, 2010 - 6:52:29 PM


  • HAL Id : tel-00408689, version 1



Delphine Marcillac. Etude multi-longueur d'onde des galaxies lumineuses en infrarouge locales. Astrophysique [astro-ph]. Université Paris Sud - Paris XI, 2005. Français. ⟨tel-00408689⟩



Record views


Files downloads