eprintid: 36068 rev_number: 13 eprint_status: archive userid: 8781 dir: disk0/00/03/60/68 datestamp: 2025-02-14 11:00:34 lastmod: 2025-02-17 10:47:22 status_changed: 2025-02-14 11:00:34 type: doctoralThesis metadata_visibility: show creators_name: Henneco, Jan title: The Progenitors and Products of Stellar Mergers subjects: ddc-520 divisions: i-130001 adv_faculty: af-13 abstract: A considerable fraction of stars live in binary systems and may exchange mass with each other. One of the outcomes of this mass transfer is a contact phase in which the two stars share a common envelope. If this contact phase is unstable, the binary components will merge and leave behind a merger product. In the first part of this thesis, we evolve several thousand binary systems with varying initial parameters and assumptions regarding the efficiency of mass transfer to trace which binaries evolve into a contact phase and which of these may merge. We identify the mechanisms leading to contact and stellar mergers, assess the influence of our assumptions, and compare our population of contact binaries to observations. In the second part of this thesis, we predict the pulsations of stellar merger products to investigate whether they differ significantly from those of genuine single stars. We find that the peculiar internal structure of these merger products affects their predicted asteroseismic signatures, both for merger products on the main sequence and more evolved merger products. With these predictions, we demonstrate the potential of asteroseismology to distinguish merger products from genuine single stars. date: 2025 id_scheme: DOI id_number: 10.11588/heidok.00036068 ppn_swb: 1917372019 own_urn: urn:nbn:de:bsz:16-heidok-360689 date_accepted: 2025-02-06 advisor: HASH(0x55e83afc83a0) language: eng bibsort: HENNECOJANTHEPROGENI full_text_status: public place_of_pub: Heidelberg citation: Henneco, Jan (2025) The Progenitors and Products of Stellar Mergers. [Dissertation] document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/36068/1/DoctoralThesis_JanHenneco_November2024.pdf