Search for dissertations about: "active galactic nuclei"

Showing result 1 - 5 of 24 swedish dissertations containing the words active galactic nuclei.

  2. 1. The environment of active galactic nuclei : excess counts and the nature of their host clusters

    Author : Margrethe Wold; Christopher D. Impey; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; astronomi;

    Abstract : This thesis presents observations of the galaxy environment of active galactic nuclei on galaxy cluster scales. In the first part, we quantify the galaxy environment of a sample of 40 quasars, consisting of equal fractions of radio-loud and radio-quiet sources. The sample covers a narrow range in redshift, 0.5 < z < 0. READ MORE

  4. 2. Active Galactic Nuclei in galaxy surveys : Empirical paths to the fiery hearts of cosmic beasts

    Author : Beatriz Villarroel; Andreas J. Korn; Takis Konstantopoulos; Moshe Elitzur; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomi;

    Abstract : Some galaxies emit excessive amounts of light from their centers, caused by accretion of gas onto super-massive black holes (SMBH). These galactic cores are often referred to as Active Galactic Nuclei (AGN) and they come in many different forms, distinguishable by their emission properties. READ MORE

  5. 3. High-redshift active galactic nuclei and their environment

    Author : Judit Fogasy; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; galaxies: evolution -- galaxies: high-redshift -- galaxies: active -- galaxies: Starburst -- -- Submillimeter: galaxies;

    Abstract : In order to understand the formation and evolution of local massive galaxies and to reveal the processes that engineered the tight correlations found between their supermassive black hole (SMBH) mass and bulge mass or velocity dispersion, the study of powerful, high-redshift active galactic nuclei (AGNs) and their environment is crucial. AGNs are luminous targets providing important clues to galaxy evolution, as their central SMBH is growing at high rates, which opens the opportunity to unfold how the growth of the black hole influences the growth of its host galaxy. READ MORE

  6. 4. Supernova surroundings on circumstellar and galactic scales

    Author : Anders Nyholm; Jesper Sollerman; Peter Lundqvist; Philip James; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; supernovae; circumstellar medium; SNe Type IIn; iPTF13z; intermediate Palomar Transient Factory; active galactic nuclei; SN 2014J; Astronomy; astronomi;

    Abstract : Some stars cease to be in a bright and destructive display called a supernova. This thesis explores what we can learn about supernovae (SNe) by studying their immediate surroundings, and what the SNe can teach us about their environments. READ MORE

  7. 5. Molecular observations of obscured galaxy nuclei

    Author : Niklas Falstad; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Galaxies: nuclei; Galaxies: ISM; Infrared: galaxies; ISM: Molecules; Submillimeter: galaxies;

    Abstract : It is becoming evident that some (ultra)luminous infrared galaxies ((U)LIRGs) contain compact obscured nuclei (CONs) where luminosities in excess of 10^9 L☉  emerge from inside dusty regions smaller than 100 pc in diameter. Due to the obscured nature of these objects, their inner regions are hidden from examination using optical or infrared lines. READ MORE