Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 17 of 17 for “"Sunyaev Zel'dovich"”.
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Using the Sunyaev-Zel'dovich effect.
This work is concerned with the Sunyaev-Zel'dovich (S-Z) effect in clusters of galaxies and its use in cosmology. In Chapter 2, I consider possible causes of error in the determination of H0 from the uncertain geometry of clusters and complications such as lack of virialisation. From numerical …
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Blind and pointed Sunyaev-Zel'dovich observations with the Arcminute Microkelvin Imager
… Imager (AMI). I focus on the detection of Sunyaev-Zel’dovich (SZ) signatures at 14-18GHz. Once the background science and operation of the instrument are described I proceed to present my contribution to the calibration of AMI, including: primary beam measurements; refinements to the known …
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The kinematic and thermal Sunyaev-Zel'dovich effects as probes of cosmology and astrophysics
… collapsed structures. This process, known as the Sunyaev-Zel'dovich effect, is usually broken down into a thermal (tSZ) and a kinematic (kSZ) contribution. While the former is sensitive to the random velocities of the electrons in the hot gas, the latter is sourced by the bulk motion of the entire …
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Properties of gas and dark matter in X-ray galaxy clusters with Sunyaev Zel'dovich measurements
… relations between the X-ray quantities and Sunyaev Zel'dovich measurements. I have observed that X-ray laws are steeper than the relations predicted from the adiabatic model. These deviations from expectations based on self-similarity are usually interpreted in terms of feedback processes …
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Fundamental Properties of Galaxy Clusters: A Prelude to Large Scale Sunyaev-Zel'dovich Effect/near-Ir Cluster Surveys
The second thrust of the dissertation is a systematic survey of the near-IR properties of cluster galaxies. With a large nearby cluster sample that spans a wide range in mass, we study scaling relations between the total galaxy luminosity or number and the cluster binding mass. The origins of such …
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Distribution of matter in clusters of galaxies
We present observations of the Sunyaev-Zel'dovich effect in 5 clusters of galaxies with a Fourier synthesis telescope - the Australia Telescope. A synthesis telescope has the advantage of simultaneously imaging the discrete radio sources and the Sunyaev-Zel'dovich effect. Observations were made at …
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Distribution of matter in clusters of galaxies
We present observations of the Sunyaev-Zel'dovich effect in 5 clusters of galaxies with a Fourier synthesis telescope - the Australia Telescope. A synthesis telescope has the advantage of simultaneously imaging the discrete radio sources and the Sunyaev-Zel'dovich effect. Observations were made at …
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Illuminating the Universe : New Probes of Reionization and Cosmology
… accessible within a few years years: the kinetic Sunyaev-Zel'dovich effect and fluctuations in the 21 cm spin flip transition of neutral hydrogen. We also propose to use the 21 cm signal to constrain cosmological parameters by probing the matter power spectrum. We also make use of the observable …
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Galaxy clusters as astrophysical laboratories and probes of cosmology
… mass fractions, entropy and density profiles, Sunyaev-Zel'dovich flux, I-band mass-to-light ratio, dominance of the brightest cluster galaxy, and central massive black hole (BH) masses, by producing synthetic observations and mimicking observational analysis techniques. These comparisons …
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Constraining dark energy using real and mock galaxy surveys
… spots and discuss possible confusion with the Sunyaev-Zel'dovich effect.
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Cosmology with Velocity Dispersion based Counts of Groups and the Effect of AGN Feedback on Host Galaxy Morphology
… of the observable (e.g., X-ray luminosity, Sunyaev-Zel'dovich flux, optical richness). Here I propose an alternative strategy, which is to directly compare predicted and observed cluster counts as a function of the one-dimensional velocity dispersion of the cluster galaxies. I show that the …
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The Galaxy and beyond with the Arcminute Microkelvin Imager
… studying galaxy clusters via observations of the Sunyaev-Zel'dovich (SZ) effect, it is also an ideal instrument for Galactic science. This thesis describes science programmes investigating both Galactic objects and galaxy clusters that I have carried out with AMI. A new data analysis pipeline is …
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Physical modelling of galaxy clusters and Bayesian inference in astrophysics
… from the second Planck catalogue (PSZ2) of Sunyaev--Zel'dovich sources. I compare the mass values obtained with data taken from the Arcminute Microkelvin Imager (AMI) radio interferometer system and from the Planck satellite. The former of these uses a Bayesian analysis pipeline that …
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Constraining the Quenching Mechanisms in Galaxies
… 4 observation of HE0515-4414 to search for the Sunyaev-Zel'dovich (SZ) signal tracing the quasar's hot halo gas. I find marginal evidence (~3.3σ) of large scale (~300 kpc) heating in the visibility plane, as well as ~3.2σ evidence of localised heating to the south west of the central quasar in …
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Exploring Galaxy Clusters and Groups with Cosmological Simulations
… addition I investigate the scaling between the Sunyaev-Zel'dovich (SZ) signal and total mass, showing good agreement with cluster data from $\textit{Planck}$ and the South Pole Telescope over a wide redshift range. I demonstrate the sensitivity of the predicted number of detected clusters in an …
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The influences of dark matter halo formation history on black hole growth, circumgalactic gas expulsion and galaxy evolution
… in both the soft X-ray luminosity and thermal Sunyaev-Zel'dovich flux, suggesting that the prediction of a strong coupling between the properties of galaxies and their halo gas fractions can be tested with measurements of these diagnostics for galaxies with diverse SFRs but similar halo masses. …
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Bayesian Modelling of Galaxy Clusters with the Arcminute Microkelvin Imager
… designed to observe galaxy clusters using the Sunyaev Zel’dovich (SZ) effect. The SA is used to observe secondary SZ anisotropies in the Cosmic Microwave Background (CMB), whilst the longer baselines of the LA make it suitable for the detection of contaminating point-like sources in the cluster …