Sökning: "galaxies: evolution"

Visar resultat 1 - 5 av 62 avhandlingar innehållade orden galaxies: evolution.

  1. 1. Star-forming Dwarf Galaxies : Internal motions and evolution

    Författare :Thomas Marquart; Nils Bergvall; Janice Lee; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Galaxy; Galaxies; Dynamics; Kinematics; Starburst; Dwarf Galaxies; Blue Compact Galaxies; Star Formation; Galaxy mergers; 3D-Spectroscopy; Spectroscopy; Astronomy; Astronomi;

    Sammanfattning : The study of dwarf galaxies is important in order to better understand the physics of the young universe and how larger galaxies form and evolve. In this work we focus on Blue Compact Galaxies (BCGs) which havemuch enhanced star formation (starbursts), causing blue colours and strong emission line spectra. LÄS MER

  3. 2. Multi frequency interferometer studies of active and starburst galaxies

    Författare :Evert Olsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; galaxies: active; galaxies: ISM; galaxies: starburst; galaxies: evolution;

    Sammanfattning : We report the results of a multi-frequency study of three interactinggalaxies: NGC 5218, NGC 1614 and NGC 4194 (the Medusa merger). These sourcesbelong to different classes of active and starburst galaxies. LÄS MER

  4. 3. On the origin and evolution of blue compact galaxies

    Författare :Göran A. Östlin; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; galaxies - compact; formation; evolution; starburst; interactions; dwarf; photometry; kinematics and dynamics; low surface brightness galaxies; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; astronomi; Astronomy;

    Sammanfattning : This thesis is focused on the origin and evolution of blue compact galaxies (BCGs). BCGs are low mass galaxies characterised by blue colours, low chemical abundances and high star formation rates. The gas consumtion time scale is considerable shorter than the age of the universe and thus the high star formation rate must be transient. LÄS MER

  5. 4. Galaxies in the epoch of reionization : Investigating the high-redshift galaxy population through simulations and observations

    Författare :Christian Binggeli; Erik Zackrisson; Sofia Ramstedt; Martin Sahlén; Stephen Wilkins; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; galaxies: high-redshift; galaxies: ISM; galaxies: evolution; reionization; Lyman continuum; Astronomy; Astronomi;

    Sammanfattning : The cosmic reionization is the last major gas phase transition in cosmic history, yet it remains poorly understood. Current constraints indicate that early star-forming galaxies drove the reionization process through producing and releasing large numbers of ionizing photons into the intergalactic medium. LÄS MER

  7. 5. Stochastic Chemical Evolution : A Study of Scatter in Relative Elemental Abundances in Extremely Metal-poor Stars

    Författare :Torgny Karlsson; Bengt Gustafsson; Mike Edmunds; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; nucleosynthesis; chemical evolution; Galactic evolution; supernovae; chemical abundances; Population II stars; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik;

    Sammanfattning : Chemical evolution addresses the problem of the formation of the chemical elements and their evolution throughout the history of the universe. This thesis discusses in particular the chemical evolution in the young universe and what we may learn from the observations of the oldest stars. LÄS MER