Dissertation/Thesis Abstract

Bright z ~ 3 Lyman break galaxies in deep wide field surveys
by Bian, Fuyan, Ph.D., The University of Arizona, 2013, 204; 3561569
Abstract (Summary)

In my thesis I investigate the luminous z ∼ 3 Lyman break galaxies in deep wide field surveys.

In the first part of the thesis, I use the LBT/LUCIFER to observe a lensed high-redshift star-forming galaxy (J0900+2234) at z = 2.03. With the high S/N near-IR spectroscopic observations, I reveal the detailed physical properties of this high-redshift galaxy, including SFR, metallicity, dust extinction, dynamical mass, and electron number density.

In the second part of the thesis, I select a large sample of LBGs at z ∼ 3 from our new LBT Boötes field survey, and study the bright end luminosity function (LF), stellar mass function (SMF) and clustering properties of bright LBGs (1L < L < 2.5L). Together with other LF and SMF measurements, the evolution of LF and SMF can be well described by continuously rising star formation history model. Using the clustering measurements in this work and other works, a tight relation between the average host galaxy halo mass and the galaxy star formation rate is found, which can be interpreted as arising from cold flow accretion. The relation also suggests that the cosmic star formation efficiency is about 5%-20% of the total cold flow mass. This cosmic star formation efficiency does not evolve with redshift (from z ∼ 5 to z ∼ 3), hosting dark matter halo mass (1011 – 1013 [special characters omitted]), or galaxy luminosity (from 0.3L* to 3L* ).

In the third and fourth parts, with the spectroscopic follow-up observations of the bright LBGs, I establish a sample of spectroscopically-confirmed ultraluminous LBGs (ULBGs) in NOAO Boo¨tes field. With this new ULBG sample, the rest-frame UV LF of LBG at M1700Å = −23.0 was measured for the first time. I find that the ULBGs have larger outflow velocity, broader Lyα emission and ISM absorption line profiles, and more prominent C IV P-Cygni profile. This profile may imply a top-heavy IMF in these ULBGs. The ULBGs have larger stellar mass and SFR, but smaller dust extinction than the typical L* LBGs at z ∼ 2 – 3. We proposed two evolutionary scenarios, pre-burst and post-burst. The properties of the ULBGs, especially the morphologies, prefer the pre-starburst scenario. Further high spatial resolution HST imaging and IFU spectroscopic observations will allow us to distinguish these two scenarios.

Indexing (document details)
Advisor: Fan, Xiaohui
Commitee: Dave, Romeel, Dey, Arjun, Green, Richard, Zabludoff, Ann
School: The University of Arizona
Department: Astronomy
School Location: United States -- Arizona
Source: DAI-B 74/09(E), Dissertation Abstracts International
Subjects: Astrophysics, Astronomy
Keywords: Break galaxies, Galaxy formation, Gravitational lensing, High redshift galaxies, Star-forming galaxies
Publication Number: 3561569
ISBN: 9781303087660