2011/10/12 by Hugo Messias, Messias, Hugo
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena
paper · pdf · doi:10.48550/arxiv.1110.2787
openalex publication_date 2011/10/12 · openalex created_date 2022/09/30 · openalex updated_date 2026/07/28
The main focus of this thesis is the IR spectral regime, which since the 70's\nand 80's has revolutionised our understanding of the Universe. A\nmulti-wavelength analysis on Extremely Red Galaxy populations is first\npresented in one of the most intensively observed patch of the sky, the Chandra\nDeep Field South. By adopting a purely statistical methodology, we consider all\nthe photometric and spectroscopic information available on large samples of\nExtremely Red Objects (EROs, 553 sources), IRAC EROs (IEROs, 259 sources), and\nDistant Red Galaxies (DRGs, 289 sources). We derive general properties:\nredshift distributions, AGN host fraction, star-formation rate densities, dust\ncontent, morphology, mass functions and mass densities. The results point to\nthe fact that EROs, IEROs, and DRGs all belong to the same population, yet seen\nat different phases of galaxy evolution. The second part of this thesis is\ndedicated to the AGN selection in the IR, with particular relevance to the\nJames Webb Space Telescope, to be launched in 2018. We develop an improved IR\ncriterion (using K and IRAC bands) as an alternative to existing IR AGN\ncriteria for the z<2.5 regime, and develop another IR criterion which reliably\nselects AGN hosts at 0<z<7 (using K, Spitzer-IRAC, and Spitzer-MIPS24um bands,\nKIM). The ability to track AGN activity since the end of reionization holds\ngreat advantages for the study of galaxy evolution. The thesis then focus on\nthe importance of dust. Based on deep IR data on the Cosmological Survey, we\nderive rest-frame 1.6, 3.3, and 6.2um luminosity functions and their dependency\non redshift. We estimate the dust contribution to those wavelengths and show\nthat the hot dust luminosity density evolves since z=1-2 with a much steeper\ndrop than the star-formation history of the Universe. Future prospects are\nfinally discussed in the last chapter.\n