Search for dissertations about: "dwarf"

Showing result 1 - 5 of 71 swedish dissertations containing the word dwarf.

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

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

    Abstract : 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. READ MORE

  2. 2. Dark matter signal normalisation for dwarf spheroidal galaxies : A frequentist analysis of stellar kinematics for indirect Dark Matter searches

    Author : Andrea Chiappo; Jan Conrad; Piero Ullio; Stockholms universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; dark matter; dwarf galaxies; kinematics and dynamics of galaxies; fysik; Physics;

    Abstract : Indirect detection strategies of Dark Matter (DM) entail searching for signals of DM annihilation or decay, typically in the form of excess positrons or high-energy photons above the astrophysical background, originating from (inferred) DM-rich environments. Due to their characteristics, dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are considered very promising targets for indirect particle DM identification. READ MORE

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

    Author : Göran A. Östlin; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; 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;

    Abstract : 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. READ MORE

  4. 4. Future stratospheric ozone depletion will affect a subarctic dwarf shrub ecosystem

    Author : Ulf Johanson; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Vaccinium; UVB; subarctic; shoot growth; ozone depletion; leaf thickness; irradiation system; heath ecosystem; Empetrum; dwarf shrubs; Calamagrostis; decomposition; Physiological biophysics; Växtfysiologi;

    Abstract : The stratospheric ozone depletion and the concomitant increase in ultraviolet-B (UV-B, 280-320 nm) radiation is of global concern due to the effects of UV-B on living organisms. To investigate the effects of increased levels of UV-B, a field irradiation system was established at a subarctic dwarf shrub heath in Northern Sweden (68 °N). READ MORE

  5. 5. Genetic variation and sexual reproduction in a moss with dwarf males, Homalothecium lutescens

    Author : Frida Rosengren; Biodiversitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; bryophytes; mosses; dwarf males; sexual reproduction; genetic variation; genetic structure; inbreeding; isozymes; allozymes; SNP; sporophytes; spore; fertilization; fertility;

    Abstract : Dwarf males occur in many unrelated groups of organisms. Among land plants they are unique to mosses. Moss dwarf males originate from male spores that land and germinate on the female where their final size is restricted to a few mm. Fertilization in mosses occur over short distances with swimming spermatozoids. READ MORE