Sökning: "Supernovae"

Visar resultat 21 - 25 av 74 avhandlingar innehållade ordet Supernovae.

1. 21. Supernova surroundings on circumstellar and galactic scales

   Författare :Anders Nyholm; Jesper Sollerman; Peter Lundqvist; Philip James; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supernovae; circumstellar medium; SNe Type IIn; iPTF13z; intermediate Palomar Transient Factory; active galactic nuclei; SN 2014J; Astronomy; astronomi;

   Sammanfattning : Some stars cease to be in a bright and destructive display called a supernova. This thesis explores what we can learn about supernovae (SNe) by studying their immediate surroundings, and what the SNe can teach us about their environments. LÄS MER

3. 22. Supernovae under the gravitational lens

   Författare :Christofer Gunnarsson; Joakim Edsjö; Tereasa Brainerd; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cosmology; Cosmology; Kosmologi;

   Sammanfattning : With general relativity as its foundation, the Standard Model of Cosmology has been developed, a model in which all matter is homogeneously and isotropically distributed throughout the Universe. We know for sure that this is not true since inhomogeneous structures such as galaxies, planets and synthesizers, are known to exist on small cosmological scales. LÄS MER

4. 23. The rebirth of Supernova 1987A : a study of the ejecta-ring collision

   Författare :Per Gröningsson; Claes Fransson; John Danziger; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supernovae; SN 1987A; circumstellar matter; shock waves; Astronomy and astrophysics; Astronomi och astrofysik; Astronomy; astronomi;

   Sammanfattning : Supernovae are some of the most energetic phenomena in the Universe and they have throughout history fascinated people as they appeared as new stars in the sky. Supernova (SN) 1987A exploded in the nearby satellite galaxy, the Large Magellanic Cloud (LMC), at a distance of only 168,000 light years. LÄS MER

5. 24. Tests for systematic effects in supernova cosmology

   Författare :Serena Nobili; Ariel Goobar; Bruno Leibundgut; Stockholms universitet; []
   Nyckelord :Cosmology; supernovae; astrophysics;

   Sammanfattning : Type~Ia supernovae are used as standard candles to measure the energy density components of the universe. This led to the new paradigm in cosmology: only about 30\% of the universe is made by ordinary pressure-less matter, the rest is associated with an unknown form of energy with a negative equation of state parameter, called dark energy, able to drive the accelaration of the universe. LÄS MER

7. 25. Extragalactic extinction and spectral properties of Type Ia supernovae

   Författare :Linda Östman; Ariel Goobar; Avishay Gal-Yam; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Type Ia supernovae; cosmology; spectroscopy; dust extinction; quasars; axions; Physics; Fysik; fysik; Physics;

   Sammanfattning : The use of Type Ia supernovae as standardisable candles for probing cosmological parameters with high precision requires good knowledge about how the supernova light is affected along the line of sight and how the intrinsic brightness varies between objects. The work in this thesis addresses these topics. LÄS MER