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Abstract: Modern microchannel plate detectors exhibit low quantum efficiency in the extreme ultra violet range compared to those manufactured before 1990. The cause of this reduction in efficiency is unknown. We describe recent investigations into the along-channel surface compositions of a number of microchannel plates (MCPs) of varying efficiency. These compositional profiles, generated using energy-dispersive X-ray spectroscopy, provide insight into possible mechanisms underlying the efficiency reduction and may assist in efforts to restore good extreme ultraviolet (EUV) performance to MCPs through modifications to the manufacturing process. [Copyright &y& Elsevier]

We describe the development of a scintillator-coated charge coupled device (CCD) based camera for imaging small volumes of radionuclide uptake in tissues. The high-resolution gamma imager (HRGI) is a collimated, scintillator-coated, low cost, imager using low noise CCDs. The HRGI operates in photon counting mode using a peltier cooler to achieve an operating temperature of -5° C. We have measured the spatial resolution and efficiency of a prototype CCD from e2v Technologies Ltd coated with a 500-µm-thick Gadox (Gd2O2S(Tb)) layer using 59.5 keV radiation from a 241Am source and 140 keV gamma-rays from a 99 mTc source. We also describe our first images using 99 mTc phantoms. [ABSTRACT FROM AUTHOR]

Abstract: We report on a new optimal filtering algorithm for improved energy and position resolution in position sensitive Transition Edge Sensor (TES) based X-ray detectors. This algorithm takes account of the noise correlation between the detector outputs to minimise the variance on the estimated photon energy and position. Using numerical methods we show that improved energy and position resolution can be obtained than from previously published methods. Our simulations also reveal the trade-offs resulting from changes in the thermal conductances and heat capacities of the detector elements. [Copyright &y& Elsevier]

Abstract: We describe optimal filtering algorithms for determining energy and position resolution in position-sensitive Transition Edge Sensor (TES) Distributed Read-Out Imaging Devices (DROIDs). Improved algorithms, developed using a small-signal finite-element model, are based on least-squares minimisation of the total noise power in the correlated dual TES DROID. Through numerical simulations we show that significant improvements in energy and position resolution are theoretically possible over existing methods. [Copyright &y& Elsevier]

Abstract: We report on the experimental characterisation and modelling of Transition Edge Sensor (TES)-based Distributed Read-Out Imaging Devices (DROIDs), for use as position-sensitive detectors in X-ray astronomy. Latest experimental results from prototype DROIDs using Ir TESs with Au absorbers are reported. Through modelling and the development of signal processing algorithms we are able to design the DROID for optimum spectral and spatial resolution depending upon application. [Copyright &y& Elsevier]