TY - GEN A1 - Kroneberger, Monika A1 - Stanik, Eva A1 - Döhring, Thorsten T1 - Optik-Simulation für die Energiewende am Beispiel eines industriellen Infrarot-Heizofens T2 - DGaO Proceedings, 126. Tagung N2 - Im Rahmen der Energiewende sollen fossile Brennstoffe auch im Heizofen einer industriellen Pulverlackbeschichtung ersetzt werden. In der Stahlindustrie ist die Infrarottrocknung von ebenen Stahlband-Oberflächen ein bereits seit Jahren bewährtes Verfahren. Pulverlack-Beschichtungen werden jedoch oft auf komplexe Geometrien aufgetragen, bei denen eine Verschattung die Effizienz der Infrarot-Aushärtung mindert. Die Anordnung der Infrarotstrahler in der reflektierenden Heizkammer, deren Geometrie und die Verweilzeit der Bauteile sind daher die Schlüssel für erfolgreiche Prozesse. Zur Verfahrensoptimierung müssen zudem die optischen Parameter der Pulverlacke während des Prozesses bekannt sein, um die nötige Strahlungsleistung an Bauteile und unterschiedliche Lacke anpassen zu können. Messungen in der NAPUBEST-Prototypanlage werden daher mit optischen Simulationen des Aufbaus abgeglichen, um die Simulationsparameter an die Messergebnisse anzupassen und damit die Grundlage für die Auslegung von industriellen Prozessen zu gewährleisten. Hierbei wird Infrarotstrahlung mehrerer Wellenlängen berücksichtigt, um in unterschiedlichen Ofenzonen benötigte Aufheiz- und Haltephasen zu verwirklichen. N2 - Poster KW - Infrarotstrahlung KW - Optiksimulation KW - Pulverlack KW - Heizofen KW - Infrarotheizung Y1 - 2025 UR - https://www.dgao-proceedings.de/abstract/abstract_only.php?id=3151 SP - 1 EP - 1 PB - DGaO ER - TY - GEN A1 - Hudec, Rene A1 - Novakova, Hana A1 - Pritzl, Vaclav A1 - Vojnar, Jan A1 - Döhring, Thorsten T1 - CubeSat mission for the observation of meteoroid impacts on Moon T2 - DGaO Jahrestagung N2 - Recent progress in nanosatellite technologies allows to consider innovative new CubeSat missions for scientific purposes. We present and evaluate the design of a small and cost effective CubeSat mission to monitor lunar meteoroid impacts by detecting their optical flashes. The poster summarizes the results of a comprehensive survey of past and recent ground based and satellite based projects focussing on lunar impact monitoring and discusses important aspects of the proposed mission and various alternatives for their solutions. Several spacecraft orbits around Moon and their usefulness for lunar impact observation are studied. In addition, we discuss the environmental risks and challenges, which such spacecraft needs to face, mainly thermal management and radiation tolerance. Finally, we present and discuss the design an optical camera suitable to detect meteoroid impacts on the lunar surface. N2 - Poster KW - CubeSat KW - satellite KW - Moon KW - meteroid KW - impact KW - Impakt KW - Mond KW - Satellit Y1 - 2021 UR - https://dgao.de/jahrestagung/ VL - 2021 SP - 1 EP - 1 ER - TY - JOUR A1 - Cotroneo, Vicenzo A1 - Basso, Stefano A1 - Civitani, Marta A1 - Döhring, Thorsten A1 - Gibertini, Eugenio A1 - Iovenitti, Simone A1 - Magagnin, Luca A1 - Pareschi, Giovanni A1 - Sironi, Giorgia A1 - Spiga, Daniele A1 - Tagliaferri, Gianpiero A1 - Valsecchi, Giuseppe T1 - Polydopamine Coatings for Enhanced Soft X-Ray Reflectivity in Space Telescope Mirrors JF - ECS Meeting Abstracts N2 - It has been known for years that sputtered low-density coatings deposited under vacuum (e.g. carbon or B4C), applied on top of high-density metallic coatings, can enhance their reflectivity in the soft X-ray band (below ~5 keV). However, the physical deposition techniques, as vacuum-based sputtering, to produce B4C or amorphous coatings are usually difficult and highly costing. Polydopamine (PDA), a bio-polymer inspired by mussels, exhibits exceptional surface binding and it’s nowadays a popular material used in surface engineering for multipurpose applications (Ryu, 2018). PDA thin film are typically produced in aqueous solution by the oxidative polymerization of dopamine, commonly known as one of the “hormones of happiness”, resulting in nanometric PDA coating with tunable thickness and morphology. In recent years, we have introduced and investigated a novel and scalable strategy for enhancing the soft X-ray reflectivity of telescope mirrors used in space missions based on dip-liquid deposition of PDA thin films as carbon-rich coating (carbon 62.7 %wt. in DA monomer) (Cotroneo, 2022). This method is very versatile and quick and offers a low-cost alternative to conventional carbon-like coating, while maintaining or even exceeding performance in the energy range below ~5 keV. Experimental tests across three X-ray beamlines—including two synchrotron facilities—demonstrated consistent reflectivity enhancement, especially in the 1–4 keV energy range and with a good match between theoretical predictions and experimental reflectivity profiles. When applied over traditional coatings (e.g Au, Ir), the dip-liquid overcoats produced improvements of up to 100% in effective area for some specific X-ray bands compared to conventional single-metal films. These results are particularly compelling for nickel-replicated mirrors with gold coatings, a common architecture in cost-sensitive space missions. Bibliography Cotroneo, V., 2022. Dopamine dip-liquid overcoatings for soft x-ray reflectivity enhancement. SPIE Proceedings. Ryu, J. H., 2018. Polydopamine Surface Chemistry: A Decade of Discovery. ACS Applied Materials & Interfaces. KW - Röntgenteleskop KW - Röntgenspiegel Y1 - 2025 U6 - https://doi.org/10.1149/MA2025-02673247mtgabs SN - 2151-2043 VL - MA2025-02 IS - 67 SP - 3247 EP - 3247 PB - The Electrochemical Society ER - TY - CHAP A1 - Busch, Uwe A1 - Michels, Marcel A1 - Kätker, Anna A1 - Döhring, Thorsten A1 - Stanik, Eva T1 - Historical X ray images selected for UNESCO's Memory of the World Register N2 - The Deutsches Röntgen Museum” in Remscheid (Germany) is the institution that uniquely and comprehensively explores and documents the life and work of Wilhelm Conrad Röntgen and the impact of his discovery. It preserves a collection of X- ray images taken by W. C. Röntgen during his research. Among them are three images of Röntgen's own hands and those of his wife, Anna Bertha. Three more images show Röntgen's hunting rifle, which he was able to analyze internally by using the new X ray technology. These two series of historical pictures from the years 1895 and 1896 provide an outstanding illustration of the scientific revolution that Röntgen's discovery triggered especially in medicine and in materials science. Therefore, his discovery of X-rays ranks among the most groundbreaking scientific achievements of modern times. In April 2025 those very first recorded X ray photographs were added on the UNESCO Memory of the World Register. The corresponding public ceremony took place on September 10 2025 in Röntgen ´ s birth town Remscheid. Representatives of the German UNESCO Commission, of politics, and of the German Röntgen Society were present UNESCO is thus honoring not only Röntgen's groundbreaking discovery of X rays, but also the cultural, scientific, and technological implications of his early radiographs. The "Deutsches Röntgen Museum" presents six famous historical X-ray documents to the public, which are now part of UNESCO ´ s Memory of the World Register. KW - Wilhelm Conrad Röntgen KW - UNESCO KW - X-rays KW - Nobel Prize KW - museum KW - Deutsches Röntgen-Museum KW - Röntgenbild Y1 - 2025 VL - 16 SP - 1 EP - 1 PB - 16th International Conference on Astronomical X-ray Optics CY - Prag ER - TY - CHAP A1 - Döhring, Thorsten A1 - Krivanekova, Lucia A1 - Hildenbrand, Georg T1 - ASTRABAX – Scientific results of two stratospheric balloon flights T2 - 18th Pico- and Nanosatellite Workshop 2025, Abstracts Book N2 - The ASTRABAX experiment ("Aschaffenburg Stratospheric Balloon Experiment") uses a multimodal platform to study radiation exposures in the upper atmosphere. We present a modular approach to accommodate the numerous setups under the weight restriction of light unmanned free stratospheric balloon. The compartmental setup allows flexibility to address current research questions with low expenditure in costs, manpower and technology expertise. Its easy implementation is suitable for educational purposes of students in the fields of astronomy, astrobiology, and material research. Recently, two stratospheric balloons were flown to test the feasibility and connectivity of different building blocks in a temperature-controlled gondola, and to characterize the stratospheric radiation environment.The focus of the physical experiments is the observation of the UV-C spectral region using miniature UV-VIS spectrometers, and cosmic ray dosimetry with a Geiger counter. A second set of experiments assesses the effects of irradiation on polydopamine coatings intended for the application in space-born X-ray telescopes. The platform also contains samples of biological cells that are simultaneously exposed to low-dose radiation of different compositions of particle, X-ray and UV radiation. Post-flight nanoscopic measurements aim to examine changes in the spatial chromatin organization playing a crucial role in DNA-repair mechanisms. Investigations in such natural environment are of importance for high altitude atmospheric as well as space flights, for comparable exposures on other objects of the solar system and for astrobiology. KW - cosmic ray KW - radiation KW - stratospheric balloon KW - atmosphere KW - UVC KW - Stratosphären-Ballon KW - Kosmische Strahlung KW - Röntgenspiegel Y1 - 2025 VL - 2025 SP - 17 EP - 17 PB - Julius-Maximilians-Universität Würzburg CY - Würzburg ER - TY - CHAP A1 - Hudec, Rene A1 - Döhring, Thorsten T1 - Astrophysical and scientific payloads for CubeSats T2 - 18th Pico- and Nanosatellite Workshop 2025, Abstracts Book N2 - For scientific and commercial applications, CubeSats enable cost-effective missions and significantly reduce the time between mission concept and launch compared to classical large satellites. Since 2000, there has been an accelerating increase in CubeSat launches, which in turn is expected to drive up the demand for dedicated optical instruments, especially in commercially relevant areas like high-resolution optics for earth observation. We present some studies and ideas of application of CubeSats mainly in the field of astronomy and astrophysics elaborated and studied at the Czech Technical University in Prague in collaboration with Aschaffenburg University of Applied Sciences. These includes single CubeSats as well as tandem CubeSat constellations. These miniature satellites can carry miniature scientific payloads for high-energy observations of both astrophysical objects as well as targets in high earth atmosphere. The examples include miniature X-ray and UV telescopes monitors and cameras, but also optical and NIR payloads. Due to the recent progress in satellite control engineering, tandem flight arrangements of mini-satellites are currently in discussion and under consideration for future space missions. CubeSat technologies offer an interesting possibility for space-born telescope payloads based on this approach. In such scenario, two small satellites will fly at a constant distance of a few meters up to 100 meters. Thereby, the front satellite will carry the telescope optics and the second satellite the detector system. The tandem flight arrangements are crucial for design of space telescopes with larger focal distances exceeding the typical sizes of small satellites. KW - satellite KW - CubeSat KW - payload KW - tandem flight KW - Kleinsatellit Y1 - 2025 VL - 2025 SP - 12 EP - 12 PB - Julius-Maximilians-Universität Würzburg CY - Würzburg ER - TY - CHAP A1 - Döhring, Thorsten A1 - Hudec, Rene T1 - One decade of joint Bavarian-Czech projects on astronomical X-ray optics N2 - Since ten years, Aschaffenburg University of Applied Sciences and the Czech technical university in Prague are now cooperating. During the recent decade, eleven joint projects have been executed, mainly targeting the development of astronomical X-ray optics. The bilateral cooperation also included the exchange of PhD students and scientists, cost compensation for conference participations, and the sponsoring of scientific conferences (AXRO and IBWS). The scientific output up to date are more than twenty joint publications and many individual conference contributions of the project partners in addition. The Bavarian-Czech Academic Agency (BTHA) has funded all of these projects. It is the goal of the Bavarian-Czech Academic Agency to support the academic collaboration in research and education and to contribute to an increased cooperation of the two neighbored countries Bavaria and Czech Republic in general. We will give a review on one decade of our Bavarian-Czech cooperation and on the scientific results of our joint projects on astronomical X-ray optics. KW - X-ray KW - optics KW - astronomy KW - AXRO KW - IBWS KW - Röntgenoptik KW - Röntgenastronomie KW - Bayern KW - Tschechien Y1 - 2025 VL - 2025 IS - 16 SP - 1 EP - 1 PB - 16th International Conference on Astronomical X-ray Optics CY - Prag ER - TY - CHAP A1 - Stehlikova, Veronika A1 - Döhring, Thorsten A1 - Stollenwerk, Manfred A1 - Stadtmüller, Johannes A1 - Marsikova, Veronika A1 - Hudec, Rene A1 - Flachs, Dennis A1 - Burwitz, Vadim A1 - Hartner, Gisela A1 - Rukdee, Surangkhana A1 - Müller, Thomas A1 - Schmidt, Thomas A1 - Inneman, Adolf A1 - Klementova, Mariana A1 - Zeising, Sebastian A1 - Langmeier, Andreas T1 - Lobster eye type X-ray telescope with chromium-iridium coated tri-layer mirrors T2 - Proceedings of SPIE N2 - 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. KW - telescope KW - Lobster Eye KW - X-ray KW - mirror KW - iridium KW - Röntgenteleskop KW - Röntgenspiegel Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1117/12.2589266 VL - 2021 IS - 11776 SP - 1177605-1 EP - 1177605-8 PB - SPIE ER - TY - CHAP A1 - Döhring, Thorsten A1 - Stollenwerk, Manfred A1 - Stadtmüller, Johannes A1 - Zeising, Sebastian A1 - Flachs, Dennis A1 - Stehlikova, Veronika A1 - Burwitz, Vadim A1 - Krumrey, Michael K. A1 - Cotroneo, Vincenzo A1 - Klementova, Mariana T1 - Characterisation of X-ray mirrors based on chromium-iridium tri-layer coatings T2 - Proceedings of SPIE N2 - Iridium-based layer systems are highly effective mirror coatings for space-born X-ray telescopes. During the recent years, Aschaffenburg University of Applied Sciences and its partners developed stress compensated chromium-iridium coatings for such astronomical applications, using chromium as an adhesive layer between iridium reflective layer and mirror substrate. However, there was room for improvement: To overcome the disturbing reflectivity reduction of the iridium absorption edge around 2 keV photon energy, thin overcoat layers of chromium are applied in addition now. This layer system has been analyzed by atomic force microscopy and transmission electron microscopy images. Furthermore, the reflectivity of such innovative X-ray mirrors based on chromium-iridium tri-layer coatings was recently measured at PTB's four-crystal monochromator beamline at the synchrotron radiation facility BESSY II. The experimental results, obtained for photon energies between 1.9 keV and 11 keV at two grazing incidence angles (0.6 degree and 0.9 degree) and their comparison with corresponding simulations are presented in this contribution. When compared to simulations of pure iridium coatings, a significantly higher reflectivity was achieved especially in the soft X-ray regime between 2 keV and 4 keV. Such chromium-iridium tri-layer coatings have high potential to increase the effective area for X-ray telescopes in Lobster Eye Design, for Wolter-I type X-ray optics, and for silicon pore optics as considered for the ATHENA telescope of the European Space Agency. KW - iridium KW - mirror KW - X-ray KW - coating KW - telescope KW - Röntgenspiegel KW - Röntgenteleskop KW - Iridium Y1 - 2021 U6 - https://doi.org/https://doi.org/10.1117/12.2592551 VL - 2021 IS - 11776 SP - 1177607-1 EP - 11776076 PB - SPIE ER - TY - CHAP A1 - Khropost, Diana A1 - Riethmüller, Franziska A1 - Döhring, Thorsten A1 - Flachs, Dennis A1 - Hülagü, Deniz A1 - Hertwig, Andreas A1 - Cotroneo, Vincenzo A1 - Gibertini, Eugenio ED - Hudec, René ED - Pina, Ladislav T1 - Polydopamine: a bio-inspired polymer for X-ray mirror coatings and other technical applications T2 - EUV and X-ray Optics: Synergy between Laboratory and Space IX N2 - Although the organic molecule dopamine (3,4-dihydroxyphenethylamine) is commonly known as one of the “hormones of happiness”, thin polymer films of polydopamine (PDA) also have interesting technical properties. PDA is a very strong glue that sticks on almost everything, even under water. In nature, PDA is found in the byssal thread cuticles of mussels. When produced by dip-coating, the self-organizing PDA layers grow in a reproducible thickness of single or multiple molecule monolayers of a few nanometres thickness only. Here we present an optimized preparation regime as derived from polymerization analysis through absorption spectroscopy. One application is the use of thin PDA overcoatings to increase the soft X-ray reflectivity of astronomical X-ray mirrors. Furthermore, we give an outlook to other technical applications for this interesting material, presenting this bio-inspired organic polymer as an innovative technical solution for the future, with applications such as PDA-based super-capacitors and its promising role in enhancing separator materials for batteries. KW - polydopamin KW - ellipsometry KW - X-ray KW - battery KW - Röntgenspiegel KW - Beschichtung Y1 - 2025 U6 - https://doi.org/10.1117/12.3056298 VL - 2025 IS - 13531 SP - 135310H-1 EP - 135310H-11 PB - SPIE ER - TY - GEN A1 - Khropost, Diana A1 - Döhring, Thorsten A1 - Riethmüller, Franziska A1 - Hülagü, Deniz T1 - Poly-dopamine - an organic material for X-ray mirror coatings and other technical applications T2 - AXRO 2024 - 15th International Conference on Astronomical X-Ray Optics N2 - Although the organic molecule dopamine (3,4-dihydroxyphenethylamine) is commonly known as the “hormone of happiness”, thin polymer films of poly-dopamine also have interesting technical properties. When produced by dip coating, these self-organizing layers grow in a reproducible thickness of single or multiple molecule monolayers of a few nanometre thickness only. One application is the use of thin poly-dopamine overcoatings to increase the soft X-ray reflectivity of astronomical X-ray mirrors. We thereby introduce a method of determining the layer thickness of poly-dopamine, which is based on spectroscopic ellipsometry measurements and applies an optical model for the poly-dopamine layers including their dielectric function. Furthermore, we give an outlook to other technical applications for this promising material, presenting this bio-inspired organic polymer as an innovative technical solution for the future. N2 - Poster KW - poly-dopamine KW - X-ray mirror KW - X-ray astronomy KW - ellipsometry KW - thin layers KW - Röntgenspiegel Y1 - 2024 VL - 2024 SP - 1 EP - 1 ER -