Open Access Te Herenga Waka-Victoria University of Wellington
Browse

Bayesian Analysis of Galaxy Clusters

Download (29.26 MB)
thesis
posted on 2024-07-29, 08:44 authored by Ryan Cox

Determining physical information from astrophysical observations often requires creating a hypothetical model and applying it to the data. For galaxy clusters we can use models of Sunyaev-Zeldovich radio or bremsstrahlung X-ray emission from the intracluster medium (ICM), or strong lensing of background galaxies to determine cluster properties and profiles like mass and pressure. In X-ray this is typically done by deriving de-projected 3D profiles from fits to the 2D surface brightness map.

Bayes-X is an existing tool that avoids the assumptions of deprojection by generating 3D models of the ICM and using them to simulate observations from a 3D source. Bayesian methods are applied to these simulations to fit the model to observed data and thus determine cluster profiles and properties. In this thesis Bayes-X is tested against real and simulated data and re-implemented to improve performance, usability and ease of development. This new version is then extensively tested to determine if it is a reliable analysis tool. This includes tests against simulated clusters where structure is well known and can be directly compared against results. Possible problems and limitations identified during testing are discussed and mitigations proposed where possible.

Recommendations are made for future development and improvements outside of the scope of this thesis.

History

Copyright Date

2024-07-29

Date of Award

2024-07-29

Publisher

Te Herenga Waka—Victoria University of Wellington

Rights License

CC BY-NC-SA 4.0

Degree Discipline

Physics

Degree Grantor

Te Herenga Waka—Victoria University of Wellington

Degree Level

Masters

Degree Name

Master of Science

ANZSRC Socio-Economic Outcome code

280120 Expanding knowledge in the physical sciences

ANZSRC Type Of Activity code

1 Pure basic research

Victoria University of Wellington Item Type

Awarded Research Masters Thesis

Language

en_NZ

Victoria University of Wellington School

School of Chemical and Physical Sciences

Advisors

Perrott, Yvette