TY - CHAP A1 - Döhring, Thorsten A1 - Stollenwerk, Manfred A1 - Proserpio, Laura A1 - Breunig, Elias A1 - Friedrich, Peter T1 - The challenging development of lightweight glass mirrors for future X-ray telescopes T2 - DGaO Proceedings N2 - Previously used mirror technologies are not able to fulfill the challenging requirements of future X-ray telescopes. A promising new technology under development is the hot slumping of thin glasses. Challenges, design trades and first results are presented, including the thermal shaping process, the development of low stress coatings and the mirror segments integration concept. KW - astronomy KW - telescope KW - mirror KW - X-ray KW - glass KW - Röntgenteleskop KW - Röntgenspiegel Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?nbn:de:0287-2016-B018-0 SN - 1614-8436 VL - 2016 PB - Deutsche Gesellschaft für angewandte Optik CY - Erlangen ER - TY - CHAP A1 - Döhring, Thorsten A1 - Probst, Anne-Catherine A1 - Emmerich, Florian A1 - Stollenwerk, Manfred A1 - Stehlikova, Veronika A1 - Friedrich, Peter A1 - Damm, Christine T1 - Development of iridium coated X-ray mirrors for astronomical applications T2 - Proceedings of the International Society for Optics and Photonics (SPIE) N2 - Future space-based X-ray observatories need to be very lightweight for launcher mass constraints. Therefore they will use a reduced mirror thickness, which results in the additional requirement of low coating stress to avoid deformation of the initial precisely shaped mirror substrates. Due to their excellent reflection properties iridium coatings are sometimes applied for grazing incidence mirrors in astronomical X-ray telescopes. At Aschaffenburg University of Applied Sciences the coating of thin iridium films by an RF-magnetron sputtering technique is under development. The work is embedded in collaborations with the Max-Planck-Institute for Extraterrestrial Physics in Germany, the Czech Technical University in Prague, the Osservatorio Astronomico di Brera in Italy, the German Leibniz Institute for Solid State and Materials Research in Dresden, and the French Institute Fresnel. Sputtering with different parameters leads to iridium films with different properties. The current work is focused on the microstructure of the iridium coatings to study the influence of the substrate and of the argon gas pressure on the thin film growing process. Correlations between coating density, surface micro-roughness, the crystalline structure of the iridium layers, and the expected reflectivity of the X-ray mirror as well as coating stress effects are presented and discussed. The final goal of the project is to integrate the produced prototype mirrors into an X-ray telescope module. On a longer timescale measurements of the mirror modules optical performance are planned at the X-ray test facility PANTER. KW - X-ray KW - telescope KW - mirror KW - iridium KW - coating KW - Iridium KW - Röntgenteleskop Y1 - 2017 U6 - https://doi.org/10.1117/12.2273988 VL - 2017 IS - 10399 SP - 103991C-1 EP - 103991C-8 PB - SPIE ER - TY - CHAP A1 - Döhring, Thorsten A1 - Stieglitz, Veronika A1 - Hudec, Rene A1 - Sapsai, Iryna A1 - Friedrich, Peter A1 - Burwitz, Vadim T1 - Characterization of a lobster-eye type X-ray telescope T2 - EOSAM-Conference N2 - Lobster-eye type X-ray telescopes use reflecting plano mirrors under grazing incidence and can observe a large field of view. As part of a Bavarian-Czech cooperation, two telescopes were build, equipped with mirrors coated with gold and iridium. Their X-ray characterization was carried out at the PANTER test facility, which simulates parallel starlight incident on the telescopes. The telescopes have an angular resolution of about 4 arc minutes in X-rays and a focal length of about 2 meters. The used X-ray mirrors reflect and focus visible light as well; their functionality in the optical regime was checked in laboratory tests. Now another test campaign will be carried out to examine the telescope resolution for real objects of the visible night sky and the imaging properties for star constellations. KW - Lobster-Eye KW - X-ray KW - telescope KW - iridium KW - mirror KW - Röntgenteleskop KW - Iridium KW - Röntgenspiegel Y1 - 2022 UR - https://www.europeanoptics.org/events/eos/eosam2022.html VL - 2022 SP - 1 EP - 1 ER - TY - CHAP A1 - Stehlikova, Veronika A1 - Döhring, Thorsten A1 - Schäfer, Tobias A1 - Stollenwerk, Manfred A1 - Friedrich, Peter A1 - Burwitz, Vadim A1 - Hartner, Gisela A1 - Bradshaw, Miranda A1 - Liao, Yingyu A1 - Pelliciari, Carlo T1 - X-ray reflectivity measurements at chromium-iridium tri-layer coatings T2 - Proceedings of SPIE N2 - Studying astronomical objects in the X-ray regime, iridium-based layer systems are highly effective reflective materials for telescopes mirrors. Aschaffenburg University and the Czech Technical University in Prague jointly developed stress compensated chromium-iridium coatings. To overcome the disturbing reflectivity reduction of the iridium absorption edge around 2 keV photon energy and improve general reflectivity at lower incident energies, thin overcoat layers of chromium have been applied in addition. Corresponding measurements at several X-ray lines have been performed on these samples at the PANTER test facility of the Max-Planck Institute for extraterrestrial Physics. A part of the experimental results and their comparison with theoretical simulations are presented in this contribution. KW - iridium KW - mirror KW - coating KW - reflectivity KW - X-ray KW - Röntgenastronomie KW - Röntgenteleskop Y1 - 2019 U6 - https://doi.org/http://dx.doi.org/10.1117/12.2530439 VL - 2019 IS - 11119 SP - 111191L-1 EP - 111191L-6 ER - TY - CHAP A1 - Hudec, Rene A1 - Stieglitz, Veronika A1 - Döhring, Thorsten A1 - Friedrich, Peter A1 - Burwitz, Vadim T1 - Novel X-ray optics developed within the AHEAD2020 project T2 - DGaO-Proceedings N2 - We present a summary of our contribution to the EU Horizon 2020 project AHEAD2020, with emphasis on the X-ray optics work package. The Czech Technical University – together with other collaborating institutes – studied innovative Lobster Eye and Kirkpatrick-Baez X-ray modules, based on the Multi Foil Optics technology. In addition, a student’s workshop in December 2023 and a summer school in May 2024 were organized within the project. KW - X-ray KW - optics KW - telescope KW - Lobster Eye KW - mirror KW - Röntgenoptik Y1 - 2025 UR - https://www.dgao-proceedings.de/download/126/126_p5.pdf SN - 1614-8436 VL - 2025 IS - 126 SP - 1 EP - 2 PB - DGaO ER -