Sökning: "Host galaxies"

Visar resultat 1 - 5 av 20 avhandlingar innehållade orden Host galaxies.

  1. 1. Quasar host galaxies at intermediate and high redshifts

    Författare :Eva Örndahl; Bengt Gustafsson; Jari Kotilainen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Active galaxies; Quasars; Host galaxies; Imaging; Photometry; Magnitudes; Colours; Morphology; Statistical methods; High-redshift; Infrared; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; Theoretical Astrophysics; teoretisk astrofysik;

    Sammanfattning : Quasars form one of the most energetic phenomena in the universe, and can be traced out to very large redshifts. By studying the galaxies which host the active nuclei, important insights can be gained into the processes that trigger and maintain the quasar powerhouse. LÄS MER

  3. 2. Radio Studies of Circumnuclear Gas in Active Galaxies

    Författare :Ylva Pihlström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; techniques: interferometry; galaxies: starbust; galaxies: active; galaxies: nuclei; radio lines: galaxies; techniques: high angular resolution;

    Sammanfattning : In this thesis we have used radio interferometry in order to perform high resolution spectral line studies of circumnuclear gas in AGN and starburst galaxies. Amongst the studied objects is the Seyfert 2 NGC5793, for which we find the high opacity HI absorption to be consistent with a 50-100 pc radius atomic disk aligned with the host galaxy disk. LÄS MER

  4. 3. Molecular observations of obscured galaxy nuclei

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

    Sammanfattning : 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. LÄS MER

  5. 4. Unveiling the nature of blue compact galaxies

    Författare :Genoveva Micheva; Göran Östlin; Evan Skillman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; blue compact galaxies; starbursts; host galaxy; stellar populations; surface photometry; optical and NIR broadband; Astronomy; astronomi;

    Sammanfattning : Blue compact galaxies (BCGs) are gas-rich star-forming low redshift galaxies with low metallicities. In some cases the relative strength of the starburst can be so high that it completely dominates the light output of the galaxy, an obstacle which has been countered by deeper optical imaging data and observations in the near infra-red (NIR) regime. LÄS MER

  7. 5. Distant supernovae and galaxies in the Stockholm VIMOS Supernova Survey

    Författare :Laia Mencia Trinchant; Göran Östlin; Duilia F de Mello; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; imaging surveys; photometric redshfits; Lyman Break galaxies; supernova typing; supernova rates; supernova host galaxies; Astronomy; Astronomi; Astronomy; astronomi;

    Sammanfattning : Multi colour imaging surveys help astronomers to find galaxies and clusters,and to gain insights on their physical properties and evolution. In this thesis, I present the Stockholm VIMOS Supernova Survey (SVISS), where the ELAIS-S field was observed with VIMOS UBVRI broad-band optical bands over a period of 5 years. LÄS MER