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High-resolution imaging X-ray spectrometers
Strüder, L.
The successful commissioning of the XMM-Newton focal plane detectors, radiation hard X-ray imaging spectroscopic CCDs, has attracted some attention: Reliably operating X-ray CCDs are delivering extraordinary images, recorded in a single-photon counting mode, imaged through the largest X-ray telescope ever built. The experimental boundary condition…
The quantum efficiency of pn-detectors from the near infrared to the soft X-ray region
Hartmann, R.; Stephan, K. -H.; Strüder, L.
The quantum efficiency of back-illuminated silicon pn-junction detectors is evaluated in the spectral range from 1.2 to 1400 eV, comprising the near infrared, visible, ultraviolet and soft X-ray regions. The calibrations are performed with the same device over the entire measured range, thus eliminating technological variations of the entrance win…
Particle and X-ray damage in pn-CCDs
Meidinger, Norbert; Schmalhofer, Bernhard; Strüder, Lothar
The fully depleted pn-junction charge coupled device (pn-CCD) has been developed as a detector for X-ray imaging and high-resolution spectroscopy for the X-ray satellite missions XMM and ABRIXAS. If the detector is exposed to a particle radiation environment, the energy resolution is degraded due to charge transfer losses and a dark current increa…
Modeling the energy response of pn-CCDs in the 0.2-10 keV band
Hartmann, R.; Strüder, L.; Krause, N. +5 more
A simple analytical model has been developed to explain the shape of low-energy spectra taken with pn-CCDs, which are developed as imaging spectroscopic detectors for ESA's X-ray observatory satellite X-Ray Multimirror Mission (XMM). The model has been tested on experimental data taken with test devices at the German synchrotron Berliner Elektrone…
Metal contamination analysis of the epitaxial starting material for scientific CCDs
Kemmer, J.; Strüder, L.; Krause, N. +4 more
Traces of unintentionally introduced titanium into a 3 k Ω cm float-zone epitaxial silicon at ultra low levels of 10 10 cm-3 were found to be the origin of charge transfer loss in pn-CCDs. We identified and backtracked the titanium impurity. The full-depletion design of the pn-CCD, a thin entrance window at the back of the CC…
Synchrotron calibration and response modelling of back-illuminated XMM-RGS CCDs
Bootsma, T. M. V.; van Zwet, E. J.; Brinkman, A. C. +4 more
Back-illuminated CCDs with high quantum efficiency for 0.35-2.5keV X-rays in combination with low efficiency at optical wavelengths have been developed for XMM-RGS. As part of the calibration programme, a systematic study of the CCD response in this energy range has been performed at the Synchrotron Radiation Source in Daresbury, UK. These measure…
Fabrication, test and performance of very large X-ray CCDs designed for astrophysical applications
Haberl, F.; Trümper, J.; Kendziorra, E. +26 more
A 6×6cm2 large X-ray CCD has been developed and fabricated at the Semiconductor Laboratory of the Max-Planck-Institut für Extraterrestrische Physik. The CCD has been designed for the focal plane cameras of two satellite missions. The concept is a fully depleted pn-CCD which is sensitive over the whole wafer thickness of about 300µ…
Monochromatic X-ray source for calibrating X-ray telescopes
Bräuninger, H.; Burkert, W.; Arkadiev, V. +5 more
A quasi-monochromatic X-ray source for calibrating X-ray space telescopes was developed, manufactured and tested. The source consists of a powerful X-ray tube of an open type with changeable anode targets and a regulated double-crystal monochromator.
A fast calculation algorithm for the charge transfer loss in CCDs
Strüder, L.; Krause, N.; Soltau, H. +3 more
Charge transfer loss due to deep level traps in CCDs is a common phenomenon. In single-photon counting CCDs for X-ray detection, the charge loss results in a degradation of spectroscopic resolution. The transfer loss of a signal depends on various parameters like temperature, number of transferred charges, number of charges in the preceding signal…