Sökning: "cosmic dust"

Visar resultat 1 - 5 av 11 avhandlingar innehållade orden cosmic dust.

  1. 1. Cosmic dust and heavy neutrinos

    Författare :Erik Elfgren; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik; Fysik;

    Sammanfattning : This Doctoral thesis treats two subjects. The first subject is the impact of early dust on the cosmic microwave background (CMB). The dust that is studied comes from the first generation of stars, which were hot and short-lived, ending their lives as giant supernovae. LÄS MER

  2. 2. Dust in the early universe

    Författare :Erik Elfgren; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik; Fysik;

    Sammanfattning : This Licentiate thesis treats the impact of early dust on the Cosmic Microwave Background (CMB). The dust that is studied comes from the first generation of stars, which were hot and short-lived, ending their lives as giant supernovæ. LÄS MER

  3. 3. On the Winds of Carbon Stars and the Origin of Carbon : A Theoretical Study

    Författare :Lars Mattsson; Susanne Höfner; Nils Bergvall; Kjell Olofsson; Martin Groenewegen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; AGB stars; carbon stars; mass loss; stellar winds; circumstellar matter; cosmic dust; stellar evolution; nucleosynthesis; galactic chemical evolution; Astronomy and astrophysics; Astronomi och astrofysik; Astronomy; Astronomi; Fysik; Physics;

    Sammanfattning : Carbon is the basis for life, as we know it, but its origin is still largely unclear. Carbon-rich Asymptotic Giant Branch (AGB) stars (carbon stars) play an important rôle in the cosmic matter cycle and may contribute most of the carbon in the Galaxy. LÄS MER

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

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

    Sammanfattning : 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. LÄS MER

  5. 5. 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