Sökning: "quasars: general"

Hittade 4 avhandlingar innehållade orden quasars: general.

  1. 1. Quasars and Low Surface Brightness Galaxies as Probes of Dark Matter

    Författare :Erik Zackrisson; Nils Bergvall; Kjell Olofsson; Julianne Dalcanton; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Cosmology: dark matter; gravitational lensing; quasars: general; quasars: redshift; galaxies: halos; galaxies: formation; galaxies: stellar content; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik;

    Sammanfattning : Most of the matter in the Universe appears to be in some form which does not emit or absorb light. While evidence for the existence of this dark matter has accumulated over the last seventy years, its nature remains elusive. LÄS MER

  3. 2. Observations and astrophysical modelling of the interstellar medium

    Författare :Achim Tappe; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ISM:individual: Gum nebula ; emmission lines; quasars: individual: PKS B2145 067 ; HII regions; quasars: absorption lines; interstellar medium ISM : general; stars: individual: Zeta Puppis ;

    Sammanfattning : .... LÄS MER

  4. 3. Interstellar absorption across the electromagnetic spectrum

    Författare :Achim Tappe; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interstellar medium ISM : general; supernova remnants Crab Nebula ; emission lines; — quasars: absorption lines;

    Sammanfattning : We report results of a multi-wavelength study of interstellar absorption in diffuse molecular clouds that lie in the direction of flat-spectrum quasars. Quasars as back-ground sources allow the measurement of Galactic interstellar absorption across the electromagnetic spectrum from mm to X-ray wavelengths. LÄS MER

  5. 4. Investigating the Dark Universe through Gravitational Lensing

    Författare :Teresa Riehm; Ariel Goobar; Edvard Mörtsell; Erik Zackrisson; Joachim Wambsganss; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cosmology; gravitational lensing; dark matter; galaxies; galaxy clusters; Astronomy; Astronomi; Astronomy; astronomi;

    Sammanfattning : A variety of precision observations suggest that the present universe is dominated by some unknown components, the so-called dark matter and dark energy. The distribution and properties of these components are the focus of modern cosmology and we are only beginning to understand them. LÄS MER