eprintid: 34753
rev_number: 18
eprint_status: archive
userid: 8103
dir: disk0/00/03/47/53
datestamp: 2024-05-16 08:05:27
lastmod: 2024-05-23 17:28:54
status_changed: 2024-05-16 08:05:27
type: doctoralThesis
metadata_visibility: show
creators_name: Reinoso Reinoso, Bastián Alejandro
title: Formation of massive black hole seeds through runaway stellar collisions and gas accretion in dense stellar systems
subjects: ddc-500
subjects: ddc-520
subjects: ddc-530
divisions: i-130001
adv_faculty: af-13
keywords: Star clusters, stars: Population III, Supermassive black holes
cterms_swd: Astronomie
cterms_swd: Physik
cterms_swd: Schwarzes Loch
cterms_swd: Sternhaufen
abstract: The goal of this work is to gain a better understanding of the processes that lead to the formation of massive black hole seeds in the early Universe, in order to provide insights into the rapid emergence of the highest redshift quasars. Two different seeding mechanisms were studied via numerical simulations. The first mechanism explores the onset of runaway stellar collisions in dense clusters of Population III stars, focusing on understanding the role
of an external potential for modelling the gas during the embedded phase. Stellar collision rates were also explored in a similar environment with the goal of confronting analytic estimates with numerical simulations. The study of this seeding mechanism demonstrates the plausibility of forming black hole seeds with > 1000 M⊙ through runaway stellar collisions that produce very massive stars. Furthermore, an analytic model for estimating the number of collisions in dense star clusters is presented, and the identification of a new collision channel involving perturbations on binary stars is reported.
The second seeding mechanism explored in this work deals with the emergence of supermassive stars through the interplay of gas accretion and stellar collisions in environments resembling collapsed gas clouds in atomic cooling halos. The numerical implementation developed in this work allowed for a self-consistent treatment of stellar and gas dynamics for the exploration of this mechanism. The results show that the emergence of supermassive
stars with 10^4 M⊙ is inevitable and a binary system of supermassive stars is the outcome in one third of the cases.
This thesis concludes by summarizing and discussing the results found in these studies and commenting on the future work needed to improve the models presented here.
date: 2024
id_scheme: DOI
id_number: 10.11588/heidok.00034753
ppn_swb: 1889729760
own_urn: urn:nbn:de:bsz:16-heidok-347538
date_accepted: 2024-04-15
advisor: HASH(0x558eaa787610)
language: eng
bibsort: REINOSOBASFORMATIONO
full_text_status: public
place_of_pub: Heidelberg
citation:   Reinoso Reinoso, Bastián Alejandro  (2024) Formation of massive black hole seeds through runaway stellar collisions and gas accretion in dense stellar systems.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/34753/1/Reinoso_PhD_Thesis.pdf