Costa, Michele Tomasso (2019) X-ray spectral variability of disk winds in a sample of local active galactic nuclei. Doctoral thesis, Keele University.

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In this thesis I will present the culmination of my research into the phenomenon of AGN winds using several X-ray telescopes (Suzaku, XMM-Newton and NuSTAR); I will do this primarily through the use of radiative transfer models (Sim et al. 2010). I will be outlining, in chapter 3, the radiative transfer code which I will use to demonstrate the capabilities of the model. I will then use this to study outflows in a small sample of AGN. Firstly, with an initial deep study of PDS 456 and subsequent studies of PG1211 + 143 and 1H 0707 - 495, I will aim to provide a better understanding of the structure and variability of the disk winds in these well-known AGN. Overall, these results are consistent with the view of highly-ionised FeK winds seen in many previous works, though this is found using a more physical model. With these new models I can probe the data in new ways, which I think represents an important addition to the currently held paradigm of AGN disk winds, and further enforces the hypothesis that they may be important for galaxy evolution. As the out flowing material interacts with the ISM it can impart an outward pressure (through either momentum or energy transfer) clearing the inner galaxy of material, this is thought to be the cause of the relationships between the central black hole and observable galactic parameters such as the mass of the bulge (Mbuldge) and velocity dispersion (?). The requirement for feedback is also seen in cosmic simulations as without feedback there is nothing to regulate the size of galaxies so they become much more massive than what is observed (Bower et al. 2006).

Item Type: Thesis (Doctoral)
Subjects: Q Science > QB Astronomy > QB460 Astrophysics
Divisions: Faculty of Natural Sciences > School of Chemical and Physical Sciences
Contributors: McLaughlin, Dean (Thesis advisor)
Depositing User: Lisa Bailey
Date Deposited: 04 Nov 2019 17:02
Last Modified: 04 Nov 2019 17:02

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