@article{DoehringHudec2018, author = {D{\"o}hring, Thorsten and Hudec, Rene}, title = {JEUMICO and TRILAMICO: Dimensions of successful Bavarian-Czech cooperation}, series = {Contributions of the Astronomical Observatory Skalnat{\´e} Pleso}, volume = {2018}, journal = {Contributions of the Astronomical Observatory Skalnat{\´e} Pleso}, number = {Vol. 48 / 3}, editor = {Skopal, August{\´i}n}, pages = {430 -- 436}, year = {2018}, abstract = {In December 2017 the two projects JEUMICO (an acronym for Joint European Mirror Cooperation) and TRILAMICO (standing for Trilateral Mirror Collaboration) are ending. Different aspects of this Bavarian-Czech collaboration between Aschaffenburg University and the Czech Technical University in Prague are discussed. The multiple dimensions of this cooperation are scientific achievements, public relation measures, internationalization of education, financial aspects, inter-cultural communication, and also the actual political situation within Europe.}, subject = {R{\"o}ntgenspiegel}, language = {en} } @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} } @misc{DoehringHudec2018, author = {D{\"o}hring, Thorsten and Hudec, Rene}, title = {Optics development for X-ray astronomy - a review on four joint Bavarian-Czech projects}, organization = {Hochschule Aschaffenburg}, pages = {1 -- 1}, year = {2018}, abstract = {In the years 2016 to 2018 the Bavarian-Czech Academic Agency (BTHA) funded in summary four bilateral projects between Aschaffenburg University and CVUT Prague: JEUMICO, TRILAMICO, JODEXRA, and AXROCO. The effective combination of equipment, manpower, and know-how of both partners resulted in the development of stress-compensated iridium coatings for astronomical X-ray mirrors. The findings have been published at scientific conferences and in joint papers. This poster gives a review on the social , political and educational aspects of the collaborations in form of a photo documentation.}, subject = {R{\"o}ntgenspiegel}, language = {en} } @inproceedings{DoehringStieglitzHudecetal.2022, author = {D{\"o}hring, Thorsten and Stieglitz, Veronika and Hudec, Rene and Sapsai, Iryna and Friedrich, Peter and Burwitz, Vadim}, title = {Characterization of a lobster-eye type X-ray telescope}, series = {EOSAM-Conference}, volume = {2022}, booktitle = {EOSAM-Conference}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2022}, abstract = {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.}, subject = {R{\"o}ntgenteleskop}, language = {en} } @inproceedings{DoehringStieglitzHudecetal.2022, author = {D{\"o}hring, Thorsten and Stieglitz, Veronika and Hudec, Rene and Sapsai, Iryna and Friedrich, Peter and Burwitz, Vadim}, title = {Characterization of a lobster-eye type X-ray telescope}, series = {EPJ Web of Conferences}, volume = {266 (2022)}, booktitle = {EPJ Web of Conferences}, doi = {10.1051/epjconf/202226613010}, pages = {1 -- 2}, year = {2022}, abstract = {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.}, subject = {R{\"o}ntgenteleskop}, language = {de} } @inproceedings{StehlikovaDoehringStollenwerketal.2021, author = {Stehlikova, Veronika and D{\"o}hring, Thorsten and Stollenwerk, Manfred and Stadtm{\"u}ller, Johannes and Marsikova, Veronika and Hudec, Rene and Flachs, Dennis and Burwitz, Vadim and Hartner, Gisela and Rukdee, Surangkhana and M{\"u}ller, Thomas and Schmidt, Thomas and Inneman, Adolf and Klementova, Mariana and Zeising, Sebastian and Langmeier, Andreas}, title = {Lobster eye type X-ray telescope with chromium-iridium coated tri-layer mirrors}, series = {Proceedings of SPIE}, volume = {2021}, booktitle = {Proceedings of SPIE}, number = {11776}, publisher = {SPIE}, organization = {Czech Technical University in Prague}, doi = {https://doi.org/10.1117/12.2589266}, pages = {1177605-1 -- 1177605-8}, year = {2021}, abstract = {For space-born astronomical X-ray telescopes, iridium-based reflective layer systems are known as highly effective mirrors coatings. During the recent years, Aschaffenburg University of Applied Sciences and the Czech Technical University in Prague jointly developed stress compensated chromium-iridium coatings for this application. To overcome the disturbing reflectivity reduction of the iridium absorption edge around 2 keV photon energy, thin overcoat layers of chromium were applied in addition. Now a prototype of a wide-field, imaging X-ray telescope of Lobster Eye type is assembled at the company RIGAKU. For this purpose a small series of 34 mirrors based on 100 x 50 mm semiconductor grade silicon substrates has been coated at Aschaffenburg University. The applied tri-layer system consists of a stack of 40 nm chromium, which act as adhesive layer and compensates layer stress, a 30 nm iridium thick reflective layer, and an additional overcoat layer of 6 nm chromium. This layer system have been analysed by AFM and TEM images. The mirrors are assembled into an aluminium frame to build a 2D Lobster Eye type telescope. The designed focal length of this wide field X-ray telescope is two meter. To study the performance of the tri-layer coating system, a twin LE telescope with convenient gold coatings was manufactured also. Performance measurements of both telescopes and under same conditions are planned at the PANTER test facility at the Max-Planck Institute for Extraterrestrial Physics. First experimental results, their comparison with theoretical simulations and the comparison between both models will be presented in this contribution.}, subject = {R{\"o}ntgenteleskop}, language = {en} }