The work reported in this thesis describes the development of the CCD instrumentation for the Faint Object Spectrograph on the 2.5m Isaac Newton Telescope at the Observatorio del Roque de los Muchachos, more commonly known as the La Palma Observatory. The Faint Object Spectrograph is a highly efficient, fixed-format CCD spectrograph aimed at low resolution spectrophotometry (15-20 A FWHM) over a wide spectral range (400-1050 nm). Its high throughput, compared with that of more conventional spectrographs, is due to the small number of optical surfaces, and the minimum vignetting which results from, locating the CCD inside the spectrograph camera. A CCD camera system is described which was developed primarily to test and commission the Faint Object Spectrograph, but also to assess the characteristics of the GEC P8603 CCD used In the spectrograph, and optimize its performance for this application. The use of CCDs in astronomy is now commonplace but there still remains some uncertainty as to which aspects of their performance need to be most critically assessed when choosing a device for a particular application. It is argued that it is important to consider not only the obvious characteristics such as quantum efficiency, spectral coverage, readout noise and geometrical format, but also, and particularly at astronomically relevant low-light levels, the consequences of the more subtle properties such as charge transfer efficiency, threshold effects and chip defects. The CCD detector in the Faint Object Spectrograph is located inside the spectrograph camera and needs to be positioned to high accuracy within the optical path. A microprocessor system is described which enables the CCD detector to be aligned remotely from the observer's control console. Finally, the commissioning of the Faint Object Spectrograph on the Isaac Newton Telescope is described, and some of the first results obtained during commissioning are presented in order to illustrate its potential in the field of faint object spectroscopy.

Fibre-reinforced polymer-matrix composite materials have highly attractive physical properties which justify the present rapid increase in applications within industry. However, composite materials suffer, like every structural material, from a failure to achieve their design properties. Therefore this research project has investigated the processing of resin used in composite materials. Initially the research programme has been concerned with the cure of epoxy resins (specifically Araldite MY750 epoxy resin system), the behaviour of the resin as it cures and how the extent of cure can affect the mechanical properties of components. Therefore, investigations have been carried out into how resin cure can be monitored by the NMR spectra and the relaxation time properties. There were four methods of analysing the data investigated, overall transverse relaxation time (T2) and free induction decay data (FID) data using the Oxford QP NMR analyser, transverse relaxation time data and spectral changes for the individual chemical environments using the Jeol EX270 NMR spectrometer, curemeter investigations using the vibrating needle curemeter (VNC) and finally Barcol hardness investigations during the later part of the cure cycle. Both the Jeol NMR spectrometer and the Oxford QP NMR analyser are designed for use primarily with liquid-state experimentation, however for the spectral, relaxation time, and FID investigations results were obtained far longer in the cure than expected. Also for the T2 investigations a transition period was noticed in the data obtained that corresponded to the gel of the resin as determined by known viscosity data for that resin mix at that cure temperature. The use of NMR as a curemeter technique was verified by repeating the analysis of the resin cure at 40, 60, 80 and 100°C. This data was then compared to known viscosity data and cure profiles obtained by the VNC curemeter and Barcol hardness readings on similar sized samples.

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The sensitivity of the charmonium and bottomonium spectroscopy to the short distance part of the interquark potential is critically re-examined using the latest data. We confirm that the data cannot accommodate a QCD scale parameter (Ʌ(_MS)) smaller than about 150 MeV, whereas we find no constraint on larger values of the scale parameter, contrary to a previous analysis. The effects of dynamical heavy quark masses in the loop correction to the perturbative potential is studied in detail and the effective four quark theory with a massive charmed quark is found to give an accurate description of the perturbative potential for quarkonia of mass up to about 250 GeV. Predictions for the heavy quarkonium system of toponium are found to be very sensitive to the behaviour of the short-distance region of the potential and it is argued that the experimental determination of the mass and e(^+)(^-) decay width of the 1S and 2S toponium resonances (of mass around 80 GeV) with accuracy anticipated at the forthcoming e(^+)e(^-) colliders should enable the QCD scale parameter to be determined to within ± 100 MeV. The hadronic decays of the lowest S- and P-wave states of charmonium and bottomonium are examined in the light of recent experimental determination. All but the individual P-wave decays in charmonium can be adequately accounted for using reasonable values of the strong coupling constant and we are led to believe that the discrepancy lies with wavefunction corrections.

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