E-Dissertationen: Search
Now showing items 11-20 of 111
Weak gravitational lensing analyses of clusters of galaxies
(2011-04-04)
Comprising the most massive gravitationally bound and relaxed structures in the Universe, galaxy clusters are essential in providing a deeper understanding of the properties of dark matter. Being cosmologically young ...
Star formation in galaxies and star clusters
(2011-07-14)
This thesis is devoted to star formation from galaxy-scales (approx. 10 000 pc) to sub-star cluster-scales (approx. 0.1 pc). I develop and test a new method to derive star formation histories of Galaxies from their star ...
Weak Lensing Mass Determination of Eight X-ray Selected Galaxy Clusters from the 400d Survey
(2011-01-19)
Evolution in the mass function of galaxy clusters sensitively traces both the expansion history of the Universe and cosmological structure formation. Hence, measuring the number density of galaxy clusters as a function of ...
Embedding the DFSZ–Axino in mSUGRA with R–Parity Violation and its implications for Dark Matter
(2011-01-21)
We embed the DFSZ axion in supersymmetry with broken R–parity. As Supersymmetry provides hundreds of free parameters we restrict ourselves to the lepton–number violating scenario in minimal supergravity models with ...
On the origin and nature of brown dwarfs and massive planets
(2011-03-02)
In this thesis the apparent peculiarities of brown dwarfs (BDs) are pointed out which force us to treat them as a population apart from, but yet still related to the stellar population. In particular, the properties that ...
Jets from Spinning Black Holes in Active Galactic Nuclei
(2011-02-08)
Relativistic jets are highly collimated plasma outflows that can be present in extragalactic radio sources, which are associated with active galactic nuclei (AGN). Observations give strong support for the idea that a ...
Heterotic Particle Models from various Perspectives
(2012-10-24)
We consider the compactification of heterotic string theory on toroidal orbifolds and their resolutions. In the framework of gauged linear sigma models we develop realizations of such spaces, allowing to continously vary ...
Galactic massive star forming regions near and far: a (sub)millimeter study of the Orion Molecular Cloud 1 and W49A
(2010-09-10)
Massive stars play an important role in shaping the structure of galaxies due to the large energy output during their lifetime. However, because of the short evolutionary time scales, the large extinction toward their birth ...
Weak Lensing Flexion Study
(2010-09-01)
In this thesis, I studied the higher order weak gravitational lensing effect,flexion, and some of its potential applications in cosmology.
Flexion, as a new subject in lensing, has shown its advantages in various ...
Flexion, as a new subject in lensing, has shown its advantages in various ...
Massive star-forming regions across the Galaxy: Initial stages of massive star formation in infrared high extinction clouds and Trigonometric parallaxes to 6.7GHz methanol masers
(2010-07-02)
Star-forming regions trace the spiral structure of the Galaxy. They are regions of increased column density and therefore traced well by the extinction in the mid-infrared based on the Spitzer/GLIMPSE 3.6-4.5 micron color ...