Publications (2)1.11 Total impact
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Article: The X-Ray CCDs Developed for the Joint European X-Ray Telescope.
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ABSTRACT: The charge coupled devices (CCDs) developed for the Joint European X-ray Telescope (JET-X) are described in detail. A history of the development program and device performance is given. We present results from a comprehensive study to characterize the x-ray response of the flight model focal plane detectors. The goal of the program is to calibrate the efficiency, energy resolution, gain, etc. down to a precision of ~1%. Final calibration data sets will be based on combinations of measurements and calculations. For example, the CCD quantum efficiency will be composed of discrete line measurements made at the University of Leicester test facility and calculation and synchrotron measurements from the Daresbury Synchrotron Radiation Source (SRS). The absolute normalizations will be provided by x-ray long beam pipe measurements at the Max Planck Institut für Extraterrestrische Physik (MPE) Panter test facility in Munich. Using the available data, it is shown that it is possible to calibrate the quantum efficiency, the FWHM energy resolution, and the system gain of the flight devices to better than 1%.Journal of X-Ray Science and Technology 01/1996; 6(3):269-98. · 1.11 Impact Factor -
Article: The European Photon Imaging Camera on XMM-Newton: The MOS cameras
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ABSTRACT: The EPIC focal plane imaging spectrometers on XMM-Newton use CCDs to record the images and spectra of celestial X-ray sources focused by the three X-ray mirrors. There is one camera at the focus of each mirror; two of the cameras contain seven MOS CCDs, while the third uses twelve PN CCDs, defining a circular field of view of 30$^{\prime}$ diameter in each case. The CCDs were specially developed for EPIC, and combine high quality imaging with spectral resolution close to the Fano limit. A filter wheel carrying three kinds of X-ray transparent light blocking filter, a fully closed, and a fully open position, is fitted to each EPIC instrument. The CCDs are cooled passively and are under full closed loop thermal control. A radio-active source is fitted for internal calibration. Data are processed on-board to save telemetry by removing cosmic ray tracks, and generating X-ray event files; a variety of different instrument modes are available to increase the dynamic range of the instrument and to enable fast timing. The instruments were calibrated using laboratory X-ray beams, and synchrotron generated monochromatic X-ray beams before launch; in-orbit calibration makes use of a variety of celestial X-ray targets. The current calibration is better than 10% over the entire energy range of 0.2 to 10 keV. All three instruments survived launch and are performing nominally in orbit. In particular full field-of-view coverage is available, all electronic modes work, and the energy resolution is close to pre-launch values. Radiation damage is well within pre-launch predictions and does not yet impact on the energy resolution. The scientific results from EPIC amply fulfil pre-launch expectations.http://dx.doi.org/10.1051/0004-6361:20000087.
