Physical Properties of Massive, Star-Forming Galaxies When the Universe Was Only Two Billion Years Old

• Main Author: Fu, Nicole Christina
• Language: en
• Published: 2011
• Subjects: Lyman-break galaxies; LBG; galaxy formation and evolution; high redshift; colour-colour plots; galaxy model fitting; optical photometry; infrared photometry; photometric redshift technique; cosmology; early universe; observational astrophysics; astronomy; galaxy spectra; Lyman-break technique; concentric aperture photometry; star-forming galaxies; Lyman-alpha forest; dust extinction; synthetic galaxies; Lyman-break galaxy
• Online Access: http://hdl.handle.net/10393/19956

Due to the finite speed of light and a vast, expanding universe, telescopes are just now receiving the light emitted by galaxies as they were forming in the very early universe. The light from these galaxies has been redshifted (stretched to longer, redder wavelengths) as a result of its journey through expanding space. Using sophisticated techniques and exceptional multi-wavelength optical and infrared data, we isolate a population of 378 galaxies in the process of formation when the Universe was only two billion years old. By matching the distinctive properties of the light spectra of these galaxies to models, the redshift, age, dust content, star formation rate and total stellar mass of each galaxy are determined. Comparing our results to similar surveys of galaxy populations at other redshifts, a picture emerges of the growth and evolution of massive, star-forming galaxies over the course of billions of years.