First qualification and selection of the eROSITA PNCCDs

For the X-ray astronomy instrument eROSITA a framestore PNCCD was developed by the MPI Halbleiterlabor. The PNCCD has an image area of 384×384 pixels with a size of 75 μm×75 μm. Each channel of the PNCCD has an own readout anode which allows parallel amplification and signal processing of the CCD signals of one row. The first measurements for the spectroscopic characterization of the PNCCDs are made with a special measurement setup—the so-called Cold Chuck Probe Station. The Cold Chuck Probe Station allows to fully operate the CCD without mounting and bonding the chip on a PCB as the CCD is contacted only with needles. Thus all eROSITA PNCCDs can be qualified under the same measurement conditions and with an identical electronic setup. Therefore the results can be compared directly. The spectroscopic properties of the PNCCDs, like the charge transfer efficiency and the energy resolution are measured. Also pixel defects such as bright pixels or non-transferring pixels are detected. With the Cold Chuck Probe Station a readout noise of 2.7 e - ENC can be achieved and reliable measurement results obtained. Based on these results the best PNCCDs will be selected for eROSITA

eROSITA camera array on the SRG satellite

The Spectrum-Roentgen-Gamma satellite with the extended roentgen survey with an imaging telescope array (eROSITA) x-ray telescope as scientific payload was successfully launched on July 13, 2019 and deployed in a 6-month halo orbit around the second Lagrange point of the Sun–Earth system. The telescope comprises an array of seven mirror systems with seven focal plane cameras. The spectroscopic CCD cameras are a further development of the very successful EPIC-PN camera on the XMM-Newton satellite, which is still operating after more than 20 years in space. The key component of the camera is the detector, which matches the large field of view of 1 deg to permit an all-sky survey in the energy range from 0.2 to 8 keV with state-of-the-art energy resolution. The image area of the PN-junction charge coupled device comprises 384  ×  384  pixels. The pixel size of 75  ×  75  μm2 each matches the angular resolution of the mirror system. Readout of the full frame is achieved in 9.18 ms but for thermal and onboard event preprocessing reasons, the time resolution is slowed down to 50 ms. The photon entrance window of five of the seven CCDs is equipped with an optical blocking filter, which proved to be advantageous. The improved concept and design of the eROSITA cameras will be explained as well as their operation and performance in space

Technology development of Athena WFI frame processor electronics and verification of its real-time performance

The core element of the Athena Wide-Field-Imager (WFI) is its detector assembly. The scientific raw data rate, depending on the observation mode, reaches values up to 3.65 Gbit/s. We demonstrate the error-free real-time processing capability using an input data stream that simulates scientific observations, e.g. a crab-like point source with 78,000 up to 195,000 photons per second