[B._Beckhoff,_et_al.]_Handbook_of_Practical_X-Ray_(b-ok.org).pdf

Only at the expense of further increase of power or a

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only at the expense of further increase of power, or a degradation of the noise performance. The charge handling capacity of the individual pixels was tested with the 5.5 MeV alpha particles from a radioactive 241 Am-source. Around 10 6 electrons can be properly transferred in every pixel. The spatial resolution was intensively tested in the PANTER facility with the flight mirror module in front of the focal plane. The first light image of the Large Magellanic Cloud in Fig. 4.57, as well as the quantitative analysis of the point spread function have shown a perfect alignment of the telescope system as on ground; the spatial resolution of the entire telescope system measured on ground corresponds exactly to the performance in orbit. The operating temperature of the pn-CCD on XMM in orbit is 90 C. This temperature optimizes on one side the requirement of “warm” operating XMM EPIC pn LMC 30 Dor MPE offline analysis KD / 28-Apr-2000 X-ray colours 0.3 - 5.0 keV Fig. 4.57. The Large Magellanic Cloud in X-rays. It shows the first light image of the pn-CCD camera on XMM. This data set comprises the time dependent, spatially resolved spectroscopic X-ray emission within a field of view of 30 arcmin. This corresponds approximately to our perception of the size of the moon. The image shows the area of 30 Doradus, a supernova remnant as an extended source of X-rays. The ‘north-east’ of 30 Dor shows an emission of X-rays up to 5 keV, while the ‘south-west’ rims appears much softer in X-rays. The supernova 1987A is the bright source ‘south-east’ of 30 Dor. About 40 new X-ray objects have been found in this exposure. The exposure time was about 10 h.
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X-Ray Detectors and XRF Detection Channels 277 conditions to avoid contamination and to relax stress to the mechanical structures. On the other side, it matches the need of “cold” temperatures because of leakage current reduction and efficient charge transfer. Up to now, more than 6 years after launch, no instrumentational surprise has occurred, the energy resolution is almost equal to the ground measure- ments as is the case for the charge transfer efficiency [82]. To date, the elec- trical stability of the instrument is perfect. The first light image in Fig. 4.57 qualitatively summarizes the above enthusiastic statements. 4.3.3 Frame Store pn-CCDs for ROSITA, and XEUS Future missions and other applications require pn-CCDs with smaller pixels and even faster readout. Potential applications are the German/ European ROSITA mission and ESA’s XEUS mission (Table 4.3). The first two missions shall be launched at the end of this decade, and the XEUS satellite around 2015. As in conventional CCDs, pn-CCDs equally can be designed in a frame store format. This optimizes the ratio of exposure to transfer time, but requires more space on a chip because the store area does not serve as active area but as an analog storage region (see Figs. 4.58 and 4.59).
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  • Spring '14
  • MichaelDudley

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