@inproceedings{DoehringProbstStollenwerketal.2016, author = {D{\"o}hring, Thorsten and Probst, Anne-Catherine and Stollenwerk, Manfred and Wen, Mingwu and Proserpio, Laura}, title = {Development of low-stress Iridium coatings for astronomical x-ray mirrors}, series = {Proceedings of SPIE 9905, Space Telescopes and Instrumentation 2016: Ultraviolet to Gamma Ray}, volume = {2016}, booktitle = {Proceedings of SPIE 9905, Space Telescopes and Instrumentation 2016: Ultraviolet to Gamma Ray}, number = {9905}, editor = {den Herder, Jan-Willem A. and Takahashi, Tadayuki and Bautz, Marshall}, doi = {10.1117/12.2232074}, pages = {99056S-1 -- 99056S-7}, year = {2016}, abstract = {Previously used mirror technologies are not suitable for the challenging needs of future X-ray telescopes. This is why the required high precision mirror manufacturing triggers new technical developments around the world. Some aspects of X-ray mirrors production are studied within the interdisciplinary project INTRAAST, a German acronym for "industry transfer of astronomical mirror technologies". The project is embedded in a cooperation of Aschaffenburg University of Applied Sciences and the Max-Planck-Institute for extraterrestrial Physics. One important task is the development of low-stress Iridium coatings for X-ray mirrors based on slumped thin glass substrates. The surface figure of the glass substrates is measured before and after the coating process by optical methods. Correlating the surface shape deformation to the parameters of coating deposition, here especially to the Argon sputtering pressure, allows for an optimization of the process. The sputtering parameters also have an influence on the coating layer density and on the micro-roughness of the coatings, influencing their X-ray reflection properties. Unfortunately the optimum coating process parameters seem to be contrarious: low Argon pressure resulted in better micro-roughness and higher density, whereas higher pressure leads to lower coating stress. Therefore additional measures like intermediate coating layers and temperature treatment will be considered for further optimization. The technical approach for the low-stress Iridium coating development, the experimental equipment, and the obtained first experimental results are presented within this paper.}, subject = {R{\"o}ntgenspiegel}, language = {en} } @inproceedings{ProbstDoehringSalmasoetal.2016, author = {Probst, Anne-Catherine and D{\"o}hring, Thorsten and Salmaso, Bianca and Proserpio, Laura}, title = {Shape measurement of thin glass substrates for X-ray mirrors: cross calibration of different equipments}, series = {Proceedings of European Optical Society Annual Meeting 2016}, volume = {2016}, booktitle = {Proceedings of European Optical Society Annual Meeting 2016}, publisher = {European Optical Society}, organization = {Hochschule Aschaffenburg}, pages = {2}, year = {2016}, abstract = {To predict the angular resolution of future X-ray telescopes combined from thermally formed thin glass mirror segments, submicron accuracy is required on the shape measurements of the individual mirror substrates. A dedicated cross-calibration campaign using instruments of different European research institutions is presented.}, subject = {R{\"o}ntgenspiegel}, language = {en} } @inproceedings{DoehringProbstZeising2018, author = {D{\"o}hring, Thorsten and Probst, Anne-Catherine and Zeising, Sebastian}, title = {Analyse der Schichtspannungen von R{\"o}ntgenspiegeln mit einem Weißlichtinterferometer}, series = {DGaO-Proceedings}, volume = {2018}, booktitle = {DGaO-Proceedings}, number = {2018}, publisher = {Deutsche Gesellschaft f{\"u}r angewandte Optik e.V.}, address = {Erlangen}, organization = {Hochschule Aschaffenburg}, issn = {1614-8436}, pages = {P10-1 -- P10-2}, year = {2018}, abstract = {An der Hochschule Aschaffenburg werden iridiumbasierte Schichtsysteme f{\"u}r r{\"o}ntgenastronomische Anwendungen hergestellt. Unter Nutzung eines Weißlichtinterferometers wurde hierf{\"u}r ein Verfahren zur Vermessung der inh{\"a}renten Schichtspannungen entwickelt. Erste vielversprechende Ergebnisse von spannungsarmen R{\"o}ntgenreflexionsbeschichtungen werden vorgestellt.}, subject = {R{\"o}ntgenspiegel}, language = {de} } @article{StehlikovaProbstNentvichetal.2018, author = {Stehlikova, Veronika and Probst, Anne-Catherine and Nentvich, Ondrej and Urban, Martin and Sieger, Ladislav and D{\"o}hring, Thorsten and Hudec, Ren{\´e}}, title = {Study of multiple layers coatings for X-ray mirrors}, series = {Contributions of the Astronomical Observatory Skalnat{\´e} Pleso}, volume = {2018}, journal = {Contributions of the Astronomical Observatory Skalnat{\´e} Pleso}, number = {48}, editor = {Skopal, August{\´i}n}, pages = {488 -- 497}, year = {2018}, abstract = {This paper focuses on a theoretical background that motivated the experimental campaign of multiple layer coatings of X-ray mirrors, and the first results of the testing of the prepared samples. Simulations of the use of different overcoats were performed in order to improve the reflectivity of thin iridium coatings designed for X-ray optics effective in the energy up to 10 keV. Samples based on these simulations were prepared and are being tested for the properties that influence the X-ray optical performance, such as layer homogeneity, density and surface micro-roughness. Further the topic of the coating stress was addressed, as it is an issue in case of thin, lightweight X-ray mirrors and affects the time stability of layers. The discussion and preliminary results conclude our contribution.}, subject = {R{\"o}ntgenspiegel}, language = {en} }