UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

The central engine of Active Galactic Nuclei

Salvi, Nikita; (2003) The central engine of Active Galactic Nuclei. Doctoral thesis (Ph.D), UCL (University College London). Green open access

[thumbnail of The_central_engine_of_Active_G.pdf] Text

Download (15MB)


Active Galactic Nuclei (AGN) are luminous objects thought to be powered by accretion of material onto a super-massive black hole. They emit radiation across a wide frequency range from the [gamma]-rays to the radio. X-ray emission, relativistic jets and superluminal motion are phenomena which originate close to the central power source and can be used to study conditions in the innermost regions around a black hole. To understand the central engines in these sources, I have used the high sensitivity and signal to noise XMM - Newton data to study the X-ray emission in three observationally very different AGN. Ill Zw2 is a luminous (L2-10 ~ 1045 erg s-1) radio-intermediate (i.e. intrinsically radio weak but with relativistic jets pointed straight at the observer) quasar and I have studied its radio to X-ray emission over a period of 25 years. The X-ray data for a bright (L2-10 ~ 1044 erg s-1) radio quiet Seyfert 1 galaxy MCG-2-58-22 is compared with advanced reflection models incorporating Compton reflection and re-processing of X-rays in an accretion disk in a self consistent manner. I have also studied the rapidly variable X-ray emission in a low luminosity (L2-10 ~ 1040-41 erg s-1) narrow line Seyfert 1 galaxy NGC 4051. Time resolved spectra are used to better understand the properties of various components in the X-ray emission of this source. To help discriminate between theoretical models that explain energy generation close to the central source and to obtain clues to the dominant emission mechanisms within the source I have also studied the multi-wavelength emission and the broad band spectrum (radio to X- rays) of these AGN.

Type: Thesis (Doctoral)
Qualification: Ph.D
Title: The central engine of Active Galactic Nuclei
Open access status: An open access version is available from UCL Discovery
Language: English
Additional information: Thesis digitised by ProQuest.
Keywords: Pure sciences; Active galactic nuclei
URI: https://discovery.ucl.ac.uk/id/eprint/10097779
Downloads since deposit
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item