The Faculty of Mathematics and Natural Sciences: Search
Now showing items 1-10 of 10
Quasi-Periodicity in the Parsec-Scale Jet of the Quasar 3C 345: A high resolution study using VSOP and VLBA
(2003)
We have observed the Quasar 3C345 with VSOP and the VLBA at four different frequencies (1.6GHz, 5GHz, 22GHz and 43GHz), making a total of 24 epochs, from 1997.40 to 1999.69. This study, combined with previous observations, ...
Multi-frequency analysis of intraday variable radio sources
(2003)
Active Galactic Nuclei (AGN) are known to show significant flux density variability across the whole electromagnetic spectrum on a wide range of time scales, from years to less than one day. In the radio regime, variability ...
The State and Evolution of Isolated Dense Molecular Cores
(2007)
This work presents studies of nearby (< 500 pc) dense molecular cloud cores, the sites of low-mass star formation. The sample includes starless and protostellar cores and allows to compare their properties in a homogenous ...
Variability of radio and TeV emitting X-ray binary systems: The case of LS I +61°303
(2013-09-09)
X-ray binaries contain a compact object, a black hole or a neutron star, and a normal companion star. An exclusive club of only ∼5 sources, also emits in radio and in gamma-rays. The nature of these gamma-ray binaries is ...
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 ...
The Physical Properties of Intermediate-Velocity Gas at High Galactic Latitudes
(2016-07-26)
The accretion of matter onto galactic disks, the formation of molecular clouds, and the formation of stars are of major importance for the evolution of galaxies over cosmic times. During their lifetimes, high-mass stars ...
Dust and gas in the MilkyWay: a full-sky view on the multiphase interstellar medium
(2016-11-04)
The Milky Way (MW) Galaxy is a unique laboratory to study the evolution of spiral galaxies, offering great sensitivities and angular resolutions with respect to observations of other galaxies. There, the large distance and ...
Automated Source Extraction for the Next Generation of Neutral Hydrogen Surveys
(2015-12-23)
This thesis is a first step to develop the necessary tools to automatically extract and parameterize sources from future HI surveys with ASKAP, WSRT/Apertif, and SKA.
The current approach to large-scale HI surveys, ...
The current approach to large-scale HI surveys, ...
Radio emission from massive Young Stellar Objects and their surroundings: Characterization and feedback
(2020-10-12)
Massive stars or high-mass stars dominate their galactic environments. They play a major role in the energy budget of galaxies and are essential in their evolution. However, high mass star formation is not fully understood, ...
Gas matters: The Molecular and Atomic Gas Budget in Nearby Galaxies from Centers to Outskirts
(2023-12-18)
Hydrogen is the most fundamental component of the baryonic universe, and its various phases have played a key role in its evolution from the Big Bang to the present day. To probe and study these phases of hydrogen in the ......