CHEMICAL AND THERMODYNAMIC PROPERTIES OF ACCEPT2.0 CLUSTERS
Clusters of galaxies offer tremendous insight into the formation and evolution of large scale structure in the Universe. While most of the total mass of a cluster is in the form of dark matter, the bulk of observable matter exists as a hot X-ray emitting gas called the intracluster medium (ICM). Studies of X-ray emission from the ICM reveal the thermodynamic and chemical processes that affect cluster formation and evolution.Additionally, measurements of emission lines in the X-ray spectra of clusters revealed that the ICM is polluted with heavy elements that originated in stars, mostly in galaxies. The radial distributions of those heavy elements show evidence of interplay between the ICM and the cluster core.\par In chapter 2, we describe the data reduction and spectral analysis of an archival sample of X-ray observations of clusters from the second catalog of the Archive of $Chandra$ Cluster Entropy Profile Tables (ACCEPT2.0). These clusters are used throughout this thesis to show how cluster X-ray properties can be used to test and constrain our theories of structure growth in the Universe. We also find that our analysis for the $L_{X}-T$ relation is consistent with previous works.\par We explore an analysis application of the $L_{X}-T$ relation for ACCEPT2.0 data in chapter 3 by testing a recent claim that the expansion of the Universe is not uniform in all directions. If the expansion of the universe were isotropic, the luminosity and temperature should scale similarly for clusters in all directions. Using global core-excised luminosities and temperatures for 302 ACCEPT2.0 clusters, we found that our sample measurements support the assumption of isotropic expansion.\par Chapter 4 investigates how the amount of metals in clusters' ICM changes with redshift. Previous works have shown varying results, which are more scattered when including core emission. We show that the core-excised abundances for 302 ACCEPT2.0 clusters are not statistically different between cool-core (CC) and non-cool core (NCC) clusters, and that the global metallicity content of the ICM does not change significantly as a function of luminosity or redshift. Furthermore, we explore the degree to which a small systematic bias arising from model uncertainties that affect hot and cool spectra can look like evolution if luminosity bias is not taken into account.\par Finally, chapter 5 describes the ongoing work of a data reduction pipeline for the SOAR Adaptive-Module Optical Spectrograph ($SAMOS$). $SAMOS$ is a multi-object spectrograph which will be commissioned on the SOuthern Astrophysical Research Telescope (SOAR) in 2021. The current version of the pipeline is able to produce wavelength calibrated spectra from test data using SOAR $Goodman$, and is in active development.
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- In Collections
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Electronic Theses & Dissertations
- Copyright Status
- In Copyright
- Material Type
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Theses
- Authors
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Koeppe, Dana Lindsey
- Thesis Advisors
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Donahue, Megan
- Committee Members
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Strader, Jay
Zepf, Stephen
O'Shea, Brian
Tollefson, Kirsten
- Date Published
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2021
- Subjects
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Astronomy
Astrophysics
- Program of Study
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Astrophysics and Astronomy - Doctor of Philosophy
- Degree Level
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Doctoral
- Language
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English
- Pages
- 194 pages
- Permalink
- https://doi.org/doi:10.25335/r8a2-cp66