The Faculty of Mathematics and Natural Sciences: Search
Now showing items 41-50 of 111
Statistical properties of cosmological correlation functions
(2015-04-24)
Correlation functions are an omnipresent tool in astrophysics, and they are routinely used to study phenomena as diverse as the large-scale structure of the Universe, time-dependent pulsar signals, and the cosmic microwave ...
A Study of Short-Spacing Correction for Galactic and Extragalactic Objects
(2015-02-11)
Radio telescopes can be divided into single-dish instruments and interferometer arrays. Their respective observational approaches are fundamentally different. Single dishes can make an accurate measurement of flux. However, ...
Magnetic Fields and the Formation of Aspherical Planetary Nebulae
(2015-02-19)
The general evolution of stars with initial mass between 0.8 and 8 solar masses is believed to be well understood until the last stages, when significant mass loss starts. However, an initially spherical star may evolve ...
Challenges of theoretical and numerical structure formation in a ΛCDM universe
(2015-06-22)
Systematic surveys of the extra-galactic sky have revealed the existence of large-scale structures in the Universe: the galaxy distribution is organized in a complex network of filaments surrounding underdense regions and ...
Galaxies in Milgromian Dynamics
(2015-02-04)
Since its first formulation in 1983, Milgromian dynamics (also known as modified Newtonian dynamics or MOND) has been very successful in predicting the gravitational potential of galaxies from the distribution of baryons ...
Tracing the Evolution of Local Universe Galaxies by Kinematical Studies of HI
(2015-01-14)
This work studies the neutral gas in external galaxies using the neutral atomic hydrogen (HI) line to investigate the kinematics of the gas component. This thesis consists of three parts, one part focusses on early-type ...
Investigating astrophysical plasmas with pulsars using LOFAR and other telescopes
(2015-02-19)
Pulsars are rapidly-rotating, highly-magnetised neutron stars that produce radio emission in their magnetospheres, which is detected as pulses on Earth. The focus of this thesis is observing pulsars as the means to study ...
Pulsar astrometry with VLBI and beyond
(2014-11-04)
Stars with masses about fifteen times that of the Sun end their lives in core-collapse supernovae. The outcome of the gravitational collapse of the stellar core is a compact object known as a neutron star. Typically, these ...
Exploring the nature of radio relics and halos in galaxy clusters through GHz radio observations
(2015-09-02)
Clusters of galaxies are the largest gravitationally bound systems in the Universe. A fraction of them hosts diffuse Mpc-scale synchrotron sources (referred to as radio relics and radio halos) not related to any discrete ...
The Optical System and the Astronomical Potential of A-MKID, a New Camera Using Microwave Kinetic Inductance Detector Technology
(2015-11-25)
In the framework of sub-millimeter astronomy, the need to create more efficient cameras with more pixels, with larger FoV and with higher mapping speed is highly desirable. In order to satisfy this necessity a new camera ...