Gas and star formation in galaxies are intimately linked to one another. Molecular hydrogen gas is the material out of which stars form, while the process of forming stars, in turn, depletes the reservoirs of gas in galaxies and builds up their stellar mass. Observations of star…
"18" Result
Sort By:
Massive young star clusters and OB associations (M > 10 4 [special characters omitted]) dominate the energetic feedback from stars into the interstellar medium. They contain the most massive and luminous stars in the Galaxy, which shape their environments through winds, ionizing…
This thesis investigates the modelling of massive protostellar envelopes in dust and molecular emission. A detailed study is undertaken for a sample of 30 targets believed to contain young high-mass protostars. SCUBA observations of the dust emission are used to help distinguish…
Radio continuum emission has been demonstrated to be an excellent tracer of recent star formation, yet current understanding remains empirical, and is primarily based upon integrated multi-frequency or resolved mono-chromatic radio continuum studies. In this thesis, we gain furt…
Stars are born from dense cores of gas within molecular clouds. The exact nature of the connection between these gas cores and the stars they form is an important issue in the field of star formation. In this thesis I use numerical simulations of molecular clouds to trace the ev…
The centre of the Milky Way, commonly referred to as the Galactic Centre, is roughly that region within 500 pc of the central black hole, Sagittarius A*. Within the innermost parsec around the supermassive black hole Sagittarius A* are more than a hundred massive young stars who…
This thesis presents both a study of the cluster-scale environments in which massive stars form, investigating in particular how the ionized gas in these regions relates to the molecular star-forming material, as well as detailed studies of two luminous forming stars, AFGL 2591 …
In the last few decades, the emergence of large-scale infrared surveys has led to a revolution in the study of star formation. In particular, NASA’s Spitzer Space Telescope has recently carried out mid- and far-infrared observations of numerous star formation regions with unprec…
I develop the first magnetospheric accretion model to take account of the observed complexity of T Tauri magnetic fields, and the influence of stellar coronae. It is now accepted that accretion onto classical T Tauri stars is controlled by the stellar magnetosphere, yet to date …
Over the past decade, large photometric surveys, and more recently spectroscopic follow up, have elucidated a clearer picture of galaxy evolution since the epoch of peak star formation at z = 1-3. However, despite these advancements, low mass galaxies, which exhibit much higher …
In this work, we use cosmological simulations to study patterns of star formation in galaxies that have traditionally been underrepresented in surveys of galaxy formation across cosmic history. Because simulations have typically not been tuned to produce them, dwarf galaxies and…
Ice and dust play a key role in building the Solar System. During their life cycle, these primitive components are exposed to complex physical and chemical processes. Some of the earliest remnants from the formation of the early Solar nebula still remain in comets providing a wa…
In this thesis, we aim to understand the history of active galactic nuclei (AGN). AGN typically are observed while the central black hole is actively accreting. While these are essential measurements, they do not allow us to examine a host galaxy after the active phase has compl…
This thesis aims to clarify the potential causes of the [CII] deficit in a set of local, star-forming galaxies. The [CII] deficit, measured as the decreasing trend in the ratio of [CII] 158 μm line strength to infrared luminosity in brighter galaxies, is a poorly understood obse…
X-ray surveys are an effective way to study growing supermassive black holes (SMBHs) in galaxy centers, as actively accreting SMBHs manifest themselves as active galactic nuclei (AGN) that can be observed in the X-ray in most cases. Through studying AGNs in X-ray survey fields t…
One of the most pressing open questions in star formation is the role of magnetic fields relative to turbulence and gravity, and how these three processes set the stellar initial mass function and star formation efficiency. In this work, we present the state of BLAST-TNG (the Ba…
The beginning of our Universe continues to elude us with many unanswered questions, some involving evolutionary histories of the most ancient galaxies—ultra-faint dwarfs (UFDs). Recent optical observation and cosmological simulation advancements have opened new opportunities to …
This is a dissertation in six chapters, where we aim to obtain a better understanding of the most luminous source populations at the peak epoch of cosmic star formation rate density using observational data collected with state-of-the-art facilities. Previous studies report star…