Sökning: "photometry"
Visar resultat 1 - 5 av 31 avhandlingar innehållade ordet photometry.
1. Deep photometry of galaxies : to see or not to see /Magnus Näslund
Sammanfattning : The edge-on spiral galaxy NGC 4565 and the distant galaxy cluster MS2255.7+2039 have been studied at optical wavelengths with deep photometry using the 2.56 m Nordic Optical Telescope on La Palma.By careful data reductions we traced the surface brightness of NGC 4565 to faint levels. LÄS MER
2. A study of blue low surface-brightness galaxies : surface photometry and spectroscopy
Sammanfattning : .... LÄS MER
3. Photometry of Resolved Stellar Populations in Local Group Galaxies
Sammanfattning : This thesis presents results from two projects using photometric observations to investigate stellar populations in Local Group galaxies. In the first project, Strömgren photometry is used to study stellar populations in dwarf spheroidal galaxies. LÄS MER
4. On the origin and evolution of blue compact galaxies
Sammanfattning : 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. LÄS MER
5. Circumstellar Debris Disks : Observational Studies of Cold Dust and Gas Emission in Planetary Nurseries
Sammanfattning : Planetary systems form in disks of gas and dust surrounding newborn stars. The young circumstellar environment is characterized by frequent collisions between rocky bodies, leading to a continuous production of small dust grains. LÄS MER