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Theoretical multiplet strengths for electric quadrupole transitions between 2S, 2P0, 2D, and 2F0 levels of Na I, Mg II, and Al III have been calculated using Hartree–Fock wave functions of frozen-core type. The resulting 2S–2D oscillator strengths for Na I are in good agreement with calculations by Bogaard and Orr, Boyle and Murray, and Warner; however, for Mg II there is a discrepancy of a factor of 2 between our results and those of Warner.

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The UKATC has undertaken to test and evaluate new infrared detectors being developed at Selex ES Ltd, Southampton in the UK for astronomy and space applications. Current programmes include: the evaluation of large format (1280x1024), near-infrared detectors for astronomy, the characterisation of shortwave infrared detectors (up to 2.5µm) for satellite-based earth observation, long wavelength (8 to 11µm) and very long wavelength (10 to 14.5µm cut-off) devices for cosmos applications. Future programmes include the evaluation of large format, avalanche photodiode arrays for photon-level sensing and high speed applications. Custom test facilities are being setup in order to drive and characterise the detectors at the ATC under conditions representative of the applications. In this paper the test facilities will be described along with the associated challenges to evaluate the performance of these detectors. The paper also includes an overview of the Selex ES detectors, including the ROICs and the MOVPE HgCdTe arrays, and will present the latest results from the characterisation program.