A low energy gamma ray telescope, and the results of its observations are described. The telescope consisted of four sodium iodide crystals, each of 120 cm(2) area, occulted by lead discs. Charged particles are rejected using scintillation, anti-coincidence shields. The telescop…
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itqquad Then to the Heav'n itself I cried,qquad Asking, `What Lamp had destiny to guideqquad Her little Children stumbling in the Dark?'qquad And - `A blind understandingMissing data. Heav'n replied. qquadqquadqquad Rubaiyat of Omar Khayyam It seems that not everybody in Persia …
It has been known for some time that many early–type galaxies possess halos of X–ray emitting gas. However, the properties of these halos and the processes by which they form are as yet not well understood. We have compiled the largest catalogue of X–ray luminosities to date, an…
The time delay estimation between time series is a real-world problem in gravitational lensing, an area of astrophysics. Lensing is the most direct method of measuring the distribution of matter, which is often dark, and the accurate measurement of time delays set the scale to m…
We have used data from the third and fourth science runs of the laser interferometric gravitational wave detectors LIGO and GEO600 to produce upper limits on the emission of gravitational waves from a selection of known neutron stars. Two different emission mechanisms are looked…
Most stars in the Galaxy are found in multiple systems of two or more stars orbiting together. Two stars orbiting around their centre of mass are called binary stars. In close binary stars, the evolution of one star affects its companion and evolutionary expansion of one star al…
This thesis is in three parts: 1) a kinematical study of exoplanet host stars, 2) a study of the detached eclipsing binary V1094 Tau and 3) and observations of other eclipsing binaries. Part I investigates kinematical biases between two methods of detecting exoplanets; the groun…
With the development of more and more elegant and sensitive interferometric gravitational wave detectors, we are expecting the first direct detection of gravitational waves in a short time. This triggers huge interest to develop more powerful tools to perform data analysis on th…
Cepheids are a class of variable stars that undergo regular pulsations in size and brightness. There exists a strong correlation between the period of pulsation and the average intrinsic brightness of a Cepheid; this correlation is known as the period-luminosity relation, or Lea…
Future robotic exploration missions within the Solar System, focussing on either scientific discovery or the emerging field of In-Situ Resource Utilisation (ISRU), shall require the development of technologies which are capable of exploring to ever-greater depths beneath the pla…
In this thesis we will see two targeted searches for gravitational waves (GWs) as-sociated with gamma-ray bursts (GRBs) and how to make them faster and more sensitive. The first of these is PyGRB, a matched filter search that follows up short GRB detections. The second is X-pipeli…
This thesis investigates the interplay between dust, gas, and stars at high resolution in nearby Local Group galaxy M33. Using panchromatic spectral energy distribution (SED) fitting along with ancillary gas tracer data, the star formation law is studied at scales of 100pc. A st…
The thesis focuses on the asteroseismology of main sequence B-type stars, particularly β Cephei and Be stars. Photometric observations of these stars were analysed in order to detect stellar oscillations. The photometric data analysed in this thesis were collected using the Sola…
These are privileged times to be a cosmologist. Recent years have witnessed unprecedented progress in observational and computational techniques and we now are able to quantify cosmological properties with unprecedented accuracy. My work builds upon this observational accuracy b…
In recent years, a range of detailed palaeoclimatic reconstructions have shown indications of a connection between changes in solar activity and Earth's climate. However, a process that may explain such a relationship has yet to be reliably demonstrated. One proposed mechanism c…
We present an investigation into the environments of quasars with respect to galaxy clus- ters, and environment evolution with redshift and luminosity. The positions of quasars with respect to clusters have been studied using cluster and quasar catalogues available, covering the…
Inflation is currently the most promising paradigm of the Early Universe. The simple paradigm involves a single canonical scalar field minimally coupled to gravity slowly rolling down a potential. In this thesis, we discuss an extension to the simple paradigm, multifield inflati…
This thesis concerns the analysis of continuous gravitational waves from neutron stars with non-axisymmetric rotational motion using data from ground-based interferometric gravitational wave detectors, the development of a computationally efficient algorithm for analysis of this…
As the global population urbanises, the benefits derived from contact with nature increasingly depend upon the presence of diverse urban ecological communities. These may be threatened by changes in land-cover and the intensification of land-use. A key question is how to design …