Sökning: "NATURVETENSKAP Fysik Astronomi och astrofysik Kosmologi"
Visar resultat 1 - 5 av 463 avhandlingar innehållade orden NATURVETENSKAP Fysik Astronomi och astrofysik Kosmologi.
1. Searches for Particle Dark Matter : Dark stars, dark galaxies, dark halos and global supersymmetric fits
Sammanfattning : The identity of dark matter is one of the key outstanding problems in both particle and astrophysics. In this thesis, I describe a number of complementary searches for particle dark matter. LÄS MER
2. Spectral Properties of Type Ia Supernovae and Implications for Cosmology
Sammanfattning : Type Ia supernovae can, for a short period of time, reach the same brightness as an entire galaxy. They are responsible for the creation of a large fraction of all heavy elements and can be used, as standard candles, to prove that the expansion of the universe is accelerating. Yet, we do not fully understand them. LÄS MER
3. Gravitational perturbations in plasmas and cosmology
Sammanfattning : Gravitational perturbations can be in the form of scalars, vectors or tensors. This thesis focuses on the evolution of scalar perturbations in cosmology, and interactions between tensor perturbations, in the form of gravitational waves, and plasma waves. LÄS MER
4. Direct Write Technology of SIN Tunnel Junctions for Thermometry and Microwave Devices
Sammanfattning : This thesis concerns development of SIN junction technology for thermometry and microwave detectors, as well as technology of a planar phase switch as a part of integratedmicrowave receiver.Cold-Electron Bolometer (CEB) is a sensitive detector of a microwave radiation, in which SIN tunnel junctions are used for temperature measurement of a nanoscale absorber in thesame way as in SIN thermometers. LÄS MER
5. On the Winds of Carbon Stars and the Origin of Carbon : A Theoretical Study
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