X-ray telescope to detect Dark Energy in space
PTB determines the spectral sensitivity of an X-ray detector for space mission
So-called Dark Energy is responsible for the fact that the Universe is expanding continually and presumably with increasing speed. Astronomers and physicists want to find out what type of "energy" this is in the scope of the eRosita Project, by investigating the distribution of about 100 000 galaxy clusters and of millions of Black Holes in space with a group of seven X-ray telescopes. By using two electron storage rings, PTB scientists have proved that the X-ray detector meets its specifications: With PTB's own Metrology Light Source, the shielding of perturbing UV and visible light was primarily investigated, while in the PTB lab at BESSY II in Berlin-Adlershof, the sensitivity of the detector in the soft X-ray range was detected.
The detector is a 450 micrometer thick pn-CCD chip illuminated from the rear, characterised by long-term stability and a high sensitivity to light. The detector has an ultra-thin pn-junction as an X-ray entrance window, to be able to provide evidence of - above all - radiation at low X-ray energies. A filter applied directly to the chip suppresses the perturbing radiation in the visible and in the UV ranges.
Several research institutes and companies are participating in eRosita under the auspices of the Max Planck Institute for Extraterrestrial Physics. The project is financed by the German Aerospace Center (DLR).
Contact:
Michael Krumrey, X-ray Radiometry, Working Group 7.11,
Tel.: +49 30 6392-5085,
e-mail: michael.krumrey(at)ptb.de
Frank Scholze, EUV-Radiometrie, Working Group 7.22,
Tel.: +49 30 6392-5094,
e-mail: frank.scholze(at)ptb.de
Information on eRosita
eRosita stands for Roentgen Survey with an Imaging Telescope Array
Website of the Max Planck Institute for Extraterrestrial Physics
http://www.mpe.mpg.de/projects-d.html