The formation of population III stars and their effect on cosmological structure in the early universe
type: CreativeWork
description: "The first generation of stars to form in the universe have a profound impact on their environment. These stars are responsible for beginning the universe's transition from a ""cosmic dark age"" where no sources of visible light existed, to the bright universe seen today. Additionally, these stars were believed to be the first sources of all elements heavier than lithium, which strongly affected the ability of gas to cool and permanently changed how star formation occurred. In this dissertation I present results from numerical simulations of the formation of the first generation of stars to form in the universe (""Population III"" stars) and their effects on later structure formation. I compare Enzo, the adaptive mesh refinement cosmology code used to perform all of the simulations in this work, to GADGET, a smoothed particle hydrodynamics cosmology code. Nearly identical results can be obtained when using two extremely different numerical methods, which helps to verify the correctness of both codes and strengthen the confidence of predictions made with these tools. I perform high dynamical range calculations of the formation of an ensemble of Population III stars, varying multiple simulation parameters, in a standard cold dark matter cosmology as well as with a soft ultraviolet background and in a generic warm dark matter cosmology. I find that the accretion rates of primordial protostars have been systematically overestimated by previously published work, which has profound implications for later structure formation and the reionization of the universe. Additionally, the presence of a soft ultraviolet background and warm dark matter serves to delay the onset of star formation. I propose limits on the possible mass of a warm dark matter particle. I also present results of simulations which demonstrate the effects of the HII regions and metal enrichment from Population III stars. It appears that HII regions from these stars may hasten the formation of later generati…
abstract: "The first generation of stars to form in the universe have a profound impact on their environment. These stars are responsible for beginning the universe's transition from a ""cosmic dark age"" where no sources of visible light existed, to the bright universe seen today. Additionally, these stars were believed to be the first sources of all elements heavier than lithium, which strongly affected the ability of gas to cool and permanently changed how star formation occurred. In this dissertation I present results from numerical simulations of the formation of the first generation of stars to form in the universe (""Population III"" stars) and their effects on later structure formation. I compare Enzo, the adaptive mesh refinement cosmology code used to perform all of the simulations in this work, to GADGET, a smoothed particle hydrodynamics cosmology code. Nearly identical results can be obtained when using two extremely different numerical methods, which helps to verify the correctness of both codes and strengthen the confidence of predictions made with these tools. I perform high dynamical range calculations of the formation of an ensemble of Population III stars, varying multiple simulation parameters, in a standard cold dark matter cosmology as well as with a soft ultraviolet background and in a generic warm dark matter cosmology. I find that the accretion rates of primordial protostars have been systematically overestimated by previously published work, which has profound implications for later structure formation and the reionization of the universe. Additionally, the presence of a soft ultraviolet background and warm dark matter serves to delay the onset of star formation. I propose limits on the possible mass of a warm dark matter particle. I also present results of simulations which demonstrate the effects of the HII regions and metal enrichment from Population III stars. It appears that HII regions from these stars may hasten the formation of later generati…
author: O'Shea, Brian William
language: en
keywords: population III stars
date published: 2011-11-07T16:14:08Z
date modified: 2026-07-22T22:25:27Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois - Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/27747