@inproceedings{MannDoehringStollenwerketal.2022, author = {Mann, Michael and D{\"o}hring, Thorsten and Stollenwerk, Manfred and Wenzler, Sebastian and Pribulla, Theodor and Komž{\´i}k, Richard M. and Sivanic, Peter}, title = {On the importance of the electrical grid power quality for astronomical observatories}, series = {Proceedings of SPIE: Observatory Operations: Strategies, Processes, and Systems IX}, booktitle = {Proceedings of SPIE: Observatory Operations: Strategies, Processes, and Systems IX}, editor = {Benn, Chris R. and Seaman, Robert L. and Adler, David S.}, publisher = {SPIE}, doi = {http://dx.doi.org/10.1117/12.2627227}, year = {2022}, subject = {Elektrizit{\"a}tsversorgung}, language = {en} } @inproceedings{ErmilovaHertwigDoehringetal.2024, author = {Ermilova, Elena and Hertwig, Andreas and D{\"o}hring, Thorsten and Stanik, Eva and Cotroneo, Vincenzo and Gibertini, Eugenio}, title = {Ellipsometrische Charakterisierung von Polydopamin f{\"u}r funktionelle technische Schichten}, series = {DGaO-Proceedings}, volume = {2024}, booktitle = {DGaO-Proceedings}, number = {125}, pages = {1 -- 2}, year = {2024}, abstract = {D{\"u}nne Schichten aus dem bionischen Material Polydopamin (PDA) sind heute zunehmend auch f{\"u}r innovative technische Anwendungen von Interesse. Mittels spektroskopischer Ellipsometrie wurde die dielektrische Funktion von PDA vom ultravioletten bis zum nahen infraroten Spektralbereich vermessen. {\"U}ber ein Modell wurde auch die Dicke dieser selbstorganisierenden Schichten bestimmt.}, subject = {D{\"u}nne Schicht}, language = {de} } @inproceedings{DoehringStanikPregleretal.2024, author = {D{\"o}hring, Thorsten and Stanik, Eva and Pregler, Jan and Stollenwerk, Manfred and Hildenbrand, Georg}, title = {Forschung zu Strahlensch{\"a}den mit dem Stratosph{\"a}renballon-Experiment ASTRABAX}, series = {DGaO-Proceedings}, volume = {2024}, booktitle = {DGaO-Proceedings}, number = {125}, pages = {1 -- 2}, year = {2024}, abstract = {Das Stratosph{\"a}renballon-Experiment ASTRABAX ist als multimodale Plattform der Material- und Biowissenschaften f{\"u}r Untersuchungen bei extremen Strahlenbelastungen konzipiert, mit Fokus auf dem UV-C-Spektralbereich und der kosmischen H{\"o}henstrahlung. Auswirkungen von Kombinationen aus hoch- und niederenergetischer Strahlung sind relevant, jedoch nicht ausreichend erforscht.}, subject = {Stratosph{\"a}ren-Ballon}, language = {de} } @article{AmorimSperaNicoaraetal.2024, author = {Amorim, Isilda and Spera, Natalia C.M. and Nicoara, Nicoleta and Ramasamy, Devaraj and Alves, Diana F. and Stollenwerk, Manfred and Stadtm{\"u}ller, Johannes and D{\"o}hring, Thorsten and Sadewasser, Sascha and Kolen'ko, Yury V. and Sousa, Juliana P.S.}, title = {Overall alkaline water electrolysis over active, stable, low loading iridium catalysts sputtered on nickel foam}, series = {International Journal of Hydrogen Energy}, volume = {92}, journal = {International Journal of Hydrogen Energy}, publisher = {Elsevier BV}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2024.10.306}, pages = {852 -- 864}, year = {2024}, subject = {Iridium}, language = {en} } @misc{StanikDoehringZeisingetal.2024, author = {Stanik, Eva and D{\"o}hring, Thorsten and Zeising, Sebastian and Meißner, Martin}, title = {An astronomy event at Aschaffenburg University to attract future engineering students}, series = {18th INTEGRAL/BART Workshop}, volume = {2024}, journal = {18th INTEGRAL/BART Workshop}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2024}, abstract = {In 2023 the German Federal Ministry of Education and Research (BMBF) and the German organization for science communication "Wissenschaft im Dialog" (German for: Science in dialogue) jointly proclaimed a "Science Year" with the motto "Our Universe". One of the numerous events that have been supported thereby has been that of the project "Zirkus UNI-versum" (in English: "Circus UNI-verse"), which took place in summer 2023 at Aschaffenburg University of Applied Sciences. Two school classes from the local high school "Kronberg-Gymnasium" first experienced an interactive astronomy lecture including a planetarium star show in a tent. Another highlight was the rocket car race in front of the cafeteria and the exclusive launch of a water rocket on the campus green. After the collective countdown, it reached a height of around eighty meters and thus rose higher than all the trees and buildings on the campus site. For their own exploration of the night sky the pupils obtained small cardboard star maps to assemble themselves as a homework. On the summer evenings of the following school holidays, they certainly observed the sky with a different point of view and, above all, with expert knowledge. The event has given them interesting impressions of Aschaffenburg Technical University as an attractive local education facility. The project "Zirkus UNI-versum" - and other activities for schools - intend to stimulate the interest of pupils in STEM subjects and to attract future engineering students.}, subject = {Astronomie}, language = {en} } @article{DoehringStanikZeisingetal.2025, author = {D{\"o}hring, Thorsten and Stanik, Eva and Zeising, Sebastian and Meissner, Martin}, title = {Astronomy events at Aschaffenburg University to attract future students}, series = {Acta Polytecnica}, volume = {2025}, journal = {Acta Polytecnica}, number = {65 (1)}, pages = {1 -- 6}, year = {2025}, abstract = {In 2023, the German Federal Ministry of Education and Research and the German organisation for science communication "Wissenschaft im Dialog" jointly proclaimed a "Science Year 2023" in Germany with the motto "Our Universe". One of the numerous events that have been supported has been that of the project "Zirkus UNI-versum", which took place in summer 2023 at Aschaffenburg University of Applied Sciences. This project, and other activities for schools, intend to stimulate the interest of pupils in STEM subjects and to attract future engineering students.}, subject = {Astronomie}, language = {en} } @inproceedings{StanikDoehringPregleretal.2024, author = {Stanik, Eva and D{\"o}hring, Thorsten and Pregler, Jan and K{\"a}tker, Anna and Busch, Uwe and Friedrich, Peter}, title = {Ein Besucherexperiment zur astronomischen R{\"o}ntgenoptik f{\"u}r das Deutsche R{\"o}ntgen-Museum}, series = {DGaO-Proceedings}, volume = {2024}, booktitle = {DGaO-Proceedings}, number = {125}, pages = {1 -- 2}, year = {2024}, abstract = {Im Rahmen eines gemeinsamen Entwicklungsprojekts entsteht ein neues Besucherexperiment zur astronomischen R{\"o}ntgenoptik, das im Museumslabor R{\"o}Lab im Deutschen R{\"o}ntgen-Museum aufgebaut werden soll. Das Ziel des interaktiven Exponats ist es, Begeisterung f{\"u}r die faszinierende Welt der R{\"o}ntgenastronomie zu wecken und das Berufsbild eines Astronomen zu vermitteln.}, subject = {Deutsches R{\"o}ntgen-Museum}, language = {de} } @inproceedings{StanikDoehringPregleretal.2024, author = {Stanik, Eva and D{\"o}hring, Thorsten and Pregler, Jan and K{\"a}tker, Anna and Busch, Uwe and Friedrich, Peter}, title = {A visitor experiment on astronomical X-ray optics for the "Deutsches R{\"o}ntgen-Museum"}, series = {AXRO 2024 - 15th International Conference on Astronomical X-Ray Optics}, volume = {2024}, booktitle = {AXRO 2024 - 15th International Conference on Astronomical X-Ray Optics}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2024}, abstract = {The "Deutsches R{\"o}ntgenmuseum" in Remscheid is the unique institution worldwide that researches and documents the life and work of the first Nobel Prize winner, Wilhelm Conrad R{\"o}ntgen, and the effects of his discovery of X-rays. As an integral part of the museum, the R{\"o}Lab laboratory offers visitors the opportunity to gain practical experience in X-rays, optics and technology through own experiments. As part of a joint development project, students from Aschaffenburg University of Applied Sciences are currently designing a visitor experiment on astronomical X-ray optics for the museum laboratory. An optical set-up with visible light illustrate the focusing principle of X-ray telescopes, e.g. for wide-angle optics based on the lobster-eye principle. Display boards explain the optics of various types of telescopes with accompanying text and corresponding illustrations. Modern X-ray observatories such as CHANDRA, XMM-Newton and eROSITA are presented clearly. Once implemented, the new visitor experiment inside the "Deutsches R{\"o}ntgenmuseum" intend to inspire young researchers for the fascinating world of X-ray optics and X-ray astronomy.}, subject = {Deutsches R{\"o}ntgen-Museum}, language = {en} } @inproceedings{DoehringStanikPregleretal.2025, author = {D{\"o}hring, Thorsten and Stanik, Eva and Pregler, Jan and K{\"a}tker, Anna and Busch, Uwe and Friedrich, Peter}, title = {Konzeption eines Astronomie-Besucherexperiments f{\"u}r das Deutsche R{\"o}ntgen Museum}, series = {Bayerischer Tag f{\"u}r gute Lehre}, volume = {2025}, booktitle = {Bayerischer Tag f{\"u}r gute Lehre}, publisher = {Universit{\"a}t W{\"u}rzburg}, organization = {Technische Hochschule Aschaffenburg}, pages = {1 -- 1}, year = {2025}, abstract = {Das Deutsche R{\"o}ntgen Museum in Remscheid ist eine weltweit einzigartige Institution, die das Leben und Werk des ersten Physik Nobelpreistr{\"a}gers Wilhelm Conrad R{\"o}ntgen und die Auswirkungen seiner Entdeckung der R{\"o}ntgenstrahlung erforscht und dokumentiert Als integraler Bestandteil des Museums bietet das Museumslabor R{\"o}Lab die M{\"o}glichkeit, durch eigene Experimente praktische Erfahrungen zu verschiedenen Themen rund um R{\"o}ntgenstrahlung, Optik und Technik zu sammeln Im Rahmen eines gemeinsamen Entwicklungsprojekts konzipieren Studierende der TH Aschaffenburg derzeit ein Besucherexperiment zur astronomischen R{\"o}ntgenoptik f{\"u}r das Museumslabor Das neue Besucherexperiment soll nach seiner Realisierung junge Forscherinnen und Forscher f{\"u}r die faszinierende Welt der R{\"o}ntgenoptik und der R{\"o}ntgenastronomie begeistern.}, subject = {Deutsches R{\"o}ntgen-Museum}, language = {de} } @inproceedings{DoehringKriegerStanik2025, author = {D{\"o}hring, Thorsten and Krieger, Jochen and Stanik, Eva}, title = {Praxisschock im Studium - die Erstellung komplexer Angebote f{\"u}r Satellitenkomponenten}, series = {Bayerischer Tag f{\"u}r gute Lehre}, volume = {2025}, booktitle = {Bayerischer Tag f{\"u}r gute Lehre}, publisher = {Universit{\"a}t W{\"u}rzburg}, organization = {Technische Hochschule Aschaffenburg}, pages = {1 -- 1}, year = {2025}, abstract = {Die Lehrveranstaltung „Projektstudie" im Rahmen des Studiengangs "Internationales Technisches Vertriebsmanagement" verbindet Elemente der Ingenieurwissenschaften und der Betriebswirtschaftslehre mit einem realistischen Vertriebsprojekt, hier der Erstellung eines komplexen Angebotes f{\"u}r Satellitenkomponenten. Begleitend zu der Teamarbeit am praktischen Vertriebsprojekt werden Lehrsequenzen theoretischer Natur durchgef{\"u}hrt, die dem nachhaltigen Verst{\"a}ndnis dienen und auf die Schwerpunktthemen vorbereiten. Die hohe Qualit{\"a}t der erstellten Angebotsunterlagen zeigt, dass die angestrebten Lernziele erreicht wurden. Der Praxisschock einer komplexen Angebotserstellung erfolgt f{\"u}r die Studierenden somit bereits im Studium unter Anleitung eines auf diesem Gebiet berufserfahrenen Professors und nicht erst w{\"a}hrend der Probezeit in einer ersten Vertriebsposition.}, subject = {Investitionsg{\"u}termarketing}, language = {de} } @inproceedings{StanikDoehringKrivanekovaetal.2025, author = {Stanik, Eva and D{\"o}hring, Thorsten and Krivanekova, Lucia and Meißner, Martin}, title = {„Zirkus UNI-versum" - ein Astronomie-Event f{\"u}r Schulklassen}, series = {Bayerischer Tag f{\"u}r gute Lehre}, volume = {2025}, booktitle = {Bayerischer Tag f{\"u}r gute Lehre}, publisher = {Universit{\"a}t W{\"u}rzburg}, organization = {Techniche Hochschule Aschaffenburg}, pages = {1 -- 1}, year = {2025}, abstract = {Im "Wissenschaftsjahr 2023 - Unser Universum", einer gemeinsamen Initiative des Bundesministeriums f{\"u}r Bildung und Forschung (BMBF) und Wissenschaft im Dialog (WiD), wurden zahlreiche Projekte in ganz Deutschland gef{\"o}rdert. Eines dieser Projekte war der "Zirkus UNI-versum", der an der Technischen Hochschule Aschaffenburg stattfand. Zielgruppe waren Schulklassen von benachbarten Schulen, die eingeladen wurden, bei einem Besuch auf dem Hochschul-Campus spielerisch Wissen {\"u}ber Astronomie und Raumfahrt zu sammeln. Gleichzeitig sollen mit dem Projekt (und anderen „Erlebnis-Bausteinen" unserer Schulprojekte) die Sch{\"u}lerinnen und Sch{\"u}ler f{\"u}r MINT-F{\"a}cher begeistert und zuk{\"u}nftige Studierende f{\"u}r technische Studieng{\"a}nge gewonnen werden.}, subject = {Astronomie}, language = {de} } @incollection{WisselFreudenmannPerezetal.2025, author = {Wissel, Julian and Freudenmann, Dominic and Perez, Nicolas and D{\"o}hring, Thorsten and Stadtm{\"u}ller, Johannes and Stollenwerk, Manfred}, title = {Various highly effective sputtered layer structures as catalysts for H2O2 decomposition for use in satellite engines}, series = {MaterialsWeek 2025 - Book of Abstracts}, booktitle = {MaterialsWeek 2025 - Book of Abstracts}, publisher = {Deutsche Gesellschaft f{\"u}r Materialkunde e.V. (DGM)}, address = {Sankt Augustin}, isbn = {978-3-88355-446-4}, pages = {53 -- 53}, year = {2025}, abstract = {Catalysts are frequently employed in both research and industrial applications to facilitate or accelerate chemical reactions. One such application is in monopropellant thrusters for space propulsion systems, where hydrogen peroxide (H2O2) is used as a liquid propellant. The decomposition of liquid hydrogen peroxide into water and oxygen gas, which ultimately generates thrust, can be achieved using noble metal catalysts from the platinoid group, such as platinum and iridium. This promotes the use of more environmentally friendly and less toxic propellants, such as H2O2, instead of hydrazine and nitrogen tetroxide (NTO). The optimization of coating structures with these catalytic materials is essential for future space applications, as it aims to extend the lifespan of catalyst materials and results in a better utilization of H2O2 in satellite engines. Therefore, different layer structures were deposited onto Duranit D99 pellets using a controlled magnetron sputtering process. Previous studies have shown that the used sputtering pressure has a strong influence on the structure of the deposited coatings [2][3]. Certain parameter combinations produce catalytic layers with rough textures and a highly porous microstructure, see figure 1 [1]. To improve the thermal and mechanical stability of the sputtered layers, thin adhesive layers of Titanium and Zirconium were applied beneath the catalytic layer. The pellets were then heated in an oven at 640°C for one minute to simulate the thermal effects experienced in a satellite engine during ignition. Following this, the catalytic performance of the pellets was tested in laboratory experiments using 30\% H2O2. Pellets with sputtered platinum as the catalytic coating delivered the best results. These coatings will be further evaluated in an engine test conducted at the German Aerospace Centre (DLR). Hydrogen peroxide is also expected to play a crucial role in future lunar and Martian colonization efforts. In this context, catalytic coatings would be used to decompose H2O2 to supply astronauts with water and oxygen, rather than to generate thrust in satellite engines.}, subject = {Satellitentechnik}, language = {en} } @incollection{KhropostRiethmuellerStaniketal.2025, author = {Khropost, Diana and Riethm{\"u}ller, Franziska and Stanik, Eva and D{\"o}hring, Thorsten and Hertwig, Andreas and Huelague, Deniz}, title = {Polydopamine - a bionic material and its potential applications for batteries}, series = {MaterialsWeek 2025 - Book of Abstracts}, booktitle = {MaterialsWeek 2025 - Book of Abstracts}, publisher = {Deutsche Gesellschaft f{\"u}r Materialkunde e.V. (DGM)}, address = {Sankt Augustin}, isbn = {978-3-88355-446-4}, pages = {67 -- 67}, year = {2025}, abstract = {Polydopamine (PDA) recently came into focus as an innovative material for applications in various technical fields, especially in the energy field it is considered for batteries as well as for supercapacitors. It 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. The wet-resistant adhesion ability of PDA can be used in the treatment of separator membranes in batteries, but furthermore PDA is also considered as an electrode material for batteries. We have investigated thin layers of poly-dopamine with different methods including ellipsometry, tactile measurements of the layer thickness and in situ absorption measurements during the polymerization process.}, subject = {Iridium}, language = {en} } @misc{LicciardelloDoehringStollenwerketal.2021, author = {Licciardello, Nadia and D{\"o}hring, Thorsten and Stollenwerk, Manfred and Kolen'ko, Yury V. and Petrovykh, Dmitri Y.}, title = {Innovative nanocomposite coatings for radiation shielding on satellites}, series = {EuroNanoForum}, volume = {2021}, journal = {EuroNanoForum}, organization = {International Iberian Nanotechnology Laboratory}, pages = {1}, year = {2021}, abstract = {The current trend in development of low-cost satellites is based on small dimensions combined with advanced electronics. Traditionally, radiation-sensitive electronics on satellites are protected by tungsten or lead foils, which are high-density materials and contribute significantly to the overall mass of the satellite. Here, we design and investigate temperature-gradient-resistant lightweight silane-based composites containing micro- or nano-particles of W or WO3, taking inspiration from similar approaches in the medical field. While the polymeric matrix provides flexibility under thermal gradients (such as those occurring in satellites during their orbits) and low density, the particles enable shielding from soft X-rays and other radiation. For reference, thin tungsten films were deposited by magnetron sputtering. The properties of the two kinds of coatings were compared and the X-ray protective properties were investigated using both a custom-designed measurement setup and conventional X-ray absorption. The best performing radiation-protective coatings will be launched in a payload experiment on the INFANTE satellite.}, subject = {Satellitentechnik}, language = {en} } @inproceedings{RivoltaBassoCivitanietal.2022, author = {Rivolta, Giacomo and Basso, Stefano and Civitani, Marta Maria and Cotroneo, Vincenzo and D{\"o}hring, Thorsten and Michler, Willy-Leopold and Pareschi, Giovanni and Spiga, Daniele and Stollenwerk, Manfred}, title = {Upgrade of a laboratory X-ray diffractometer to extend its operating range towards soft energies}, series = {Proceedings of SPIE}, volume = {2022}, booktitle = {Proceedings of SPIE}, number = {12181}, publisher = {SPIE}, organization = {Osservatorio Astronomico di Brera}, issn = {0277-786X}, doi = {doi: 10.1117/12.2629940}, pages = {121814S-1 -- 121814s-7}, year = {2022}, abstract = {The optical properties of X-ray mirror samples are commonly measured using diffractometers based on laboratory sources; like the Bede D1 diffractometer operating at INAF-OAB. This instrument can generate a collimated X-ray beam up to 60 keV, even though the most interesting energy region for x-ray astronomy applications is usually below 10 keV. In the softest part of this range (below 6 keV), high X-ray absorption in air hinders a full and precise characterization of optical components. In this work, we present an upgrade of the Bede D1 diffractometer that extends the operative range of the instrument below 6 keV; this is done by maximizing the flux at lowest energies and by reducing absorption by means of a helium-rich atmosphere. The upgraded instrument will be used for the tests of X-ray mirrors with innovative soft X-ray coatings, with potential application to the next generation X-ray telescopes (such as ATHENA and eXTP).}, subject = {R{\"o}ntgenspiegel}, language = {en} } @inproceedings{CotroneoBruniCivitanietal.2022, author = {Cotroneo, Vincenzo and Bruni, Ricardo and Civitani, Marta Maria and D{\"o}hring, Thorsten and Gibertini, Eugenio and Magagnin, Luca and Pareschi, Giovanni and Rivolta, Giacomo and Romaine, Suzanne and Sethares, Leandra and Sironi, Giorgia and Tagliaferri, Gianpiero and Valsecchi, Giuseppe}, title = {Dopamine dip-liquid overcoatings for soft X-ray reflectivity enhancement}, series = {Proceedings of SPIE}, volume = {2022}, booktitle = {Proceedings of SPIE}, number = {12181}, doi = {10.1117/12.2630212}, pages = {1218117 -- 1218117}, year = {2022}, abstract = {It has been known for some time that sputtered low-density coatings deposited under vacuum (e.g. carbon or B4C), applied on top of high-density metallic coatings, can enhance the reflectivity in the soft x-ray band (below ~5 keV). In the last years, we experimented with novel carbonated coatings obtained by dip-liquid deposition, in which a thin film is formed on the surface of a mirror by immersion in a suitable precursor solution. After several attempts with different chemical compounds, we found an optimal candidate both for the reflectivity performance and for the convenience of the deposition process, which is much simpler and inexpensive compared to conventional processes. In particular, such coatings can enhance the soft x-ray response at the reflection angles employed in future telescopes, like ATHENA (ESA), Lynx (NASA) and eXTP (CAS). In this paper we consider the application of dip-liquid overcoatings on conventional coatings (Au, Ir) or in combination with recently proposed chromium overcoatings and their possible uses to enhance the reflectivity of x-ray mirrors at low, medium or higher energies, presenting the first experimental results of x-ray tests on these coatings.}, subject = {R{\"o}ntgenspiegel}, language = {en} } @inproceedings{RivoltaBruniCivitanietal.2022, author = {Rivolta, Giacomo and Bruni, Ricardo and Civitani, Marta Maria and Cotroneo, Vincenzo and D{\"o}hring, Thorsten and Gibertini, Eugenio and Magagnin, Luca and Pareschi, Giovanni and Romaine, Suzanne and Sethares, Leandra and Sironi, Giorgia and Tagliaferri, Gianpiero and Valsecchi, Giuseppe}, title = {Development in carbon-based coatings for X-ray astronomy}, series = {IWXM 2022, 7th International Workshop on Metrology for X-ray Optics, Mirror Design and Fabrication, Berlin, 5th - 8th April 2022}, booktitle = {IWXM 2022, 7th International Workshop on Metrology for X-ray Optics, Mirror Design and Fabrication, Berlin, 5th - 8th April 2022}, year = {2022}, subject = {R{\"o}ntgenastronomie}, language = {en} } @article{WisselFreudenmannCichockaetal.2024, author = {Wissel, Julian and Freudenmann, Dominic and Cichocka, Magdalena Ola and P{\"o}hl, Almut and Stephan-Hofmann, Iris and R{\"o}cke, Nicole and P{\´e}rez, Nicol{\´a}s and D{\"o}hring, Thorsten and Stadtm{\"u}ller, Johannes and Stollenwerk, Manfred}, title = {Microstructure of highly effective platinum-iridium alloys as catalysts for hydrogen peroxide decomposition}, series = {Research on Chemical Intermediates}, volume = {50}, journal = {Research on Chemical Intermediates}, number = {11}, publisher = {Springer Science and Business Media LLC}, issn = {0922-6168}, doi = {10.1007/s11164-024-05412-4}, pages = {5385 -- 5397}, year = {2024}, subject = {Iridium}, language = {en} } @incollection{StanikStollenwerkHuebneretal.2025, author = {Stanik, Eva and Stollenwerk, Manfred and H{\"u}bner, Sophie and Stadtm{\"u}ller, Johannes and D{\"o}hring, Thorsten}, title = {Experimental studies on iridium catalysts for water PEM electrolysis}, series = {MaterialsWeek 2025 - Book of Abstracts}, booktitle = {MaterialsWeek 2025 - Book of Abstracts}, publisher = {Deutsche Gesellschaft f{\"u}r Materialkunde e.V. (DGM)}, address = {Sankt Augustin}, isbn = {978-3-88355-446-4}, pages = {62 -- 62}, year = {2025}, abstract = {The enhanced use of sustainable energy sources entails strong fluctuations in the availability of electric power. As we need new approaches for energy distribution and energy storage systems, hydrogen is often discussed as a promising energy carrier. PEM electrolysis can be used to transform electrical energy from renewable sources into hydrogen. One challenge in this context is the need for catalysts, as these contribute significantly to the performance of the electrolysis cell. The commonly used platinum group metal (PGM) catalysts like Iridium are quite scarce and therefore expensive. A possible approach to reduce the Ir content is the application of magnetron sputtering for catalyst generation. By selecting the right process parameters, the desired layer properties can be set very precisely during sputtering. This ensures a large surface area with reduced material usage. The introduction of carbon can increase the surface area of the catalyst further and enhance its effectiveness. First results of investigations on the catalytic effect of sputtered Ir catalyst layers will be presented.}, subject = {Iridium}, language = {en} } @inproceedings{DoehringKrivanekovaPregleretal.2025, author = {D{\"o}hring, Thorsten and Krivanekova, Lucia and Pregler, Jan and Hildenbrand, Georg}, title = {Radiation measurements in the stratosphere by the balloon experiment ASTRABAX}, series = {EUV and X-ray Optics: Synergy between Laboratory and Space IX}, volume = {2025}, booktitle = {EUV and X-ray Optics: Synergy between Laboratory and Space IX}, number = {13531}, editor = {Hudec, Ren{\´e} and Pina, Ladislav}, publisher = {SPIE}, doi = {10.1117/12.3056175}, pages = {1353109-1 -- 1353109-11}, year = {2025}, abstract = {Stratospheric balloons are a platform of choice for meteorology, climate and atmospheric research, offering some advantages over sounding rockets and satellites. The Aschaffenburg Stratospheric Balloon Experiment (ASTRABAX) carries out experiments on material treatments and life sciences under the extreme radiation exposures at high altitude. The pioneer ASTRABAX flight took place mid of October 2024 in Germany. Measurements examined the UV spectral region by a miniature spectrometer and captured secondary cosmic rays employing a Geiger counter. Additional experiments assessed irradiation effects on polydopamine X-ray mirror coatings. The platform also carried samples of biological cells to evaluate effects of exposure to low-dose irradiation of high-energy particles, gamma rays and UV radiation simultaneously. Biological experiments under such realistic conditions are relevant for genetic research on Earth, for human space flights as well as for the understanding of astrobiological processes.}, subject = {Stratosph{\"a}ren-Ballon}, language = {en} } @inproceedings{StanikPreglerDoehringetal.2025, author = {Stanik, Eva and Pregler, Jan and D{\"o}hring, Thorsten and K{\"a}tker, Anna and Busch, Uwe and Friedrich, Peter}, title = {A visitor experiment on astronomical x-ray optics for the "Deutsches R{\"o}ntgenmuseum"}, series = {EUV and X-ray Optics: Synergy between Laboratory and Space IX}, volume = {2025}, booktitle = {EUV and X-ray Optics: Synergy between Laboratory and Space IX}, number = {13531}, editor = {Hudec, Ren{\´e} and Pina, Ladislav}, publisher = {SPIE}, doi = {10.1117/12.3056291}, pages = {135310M-1 -- 135310M-7}, year = {2025}, abstract = {The "Deutsches R{\"o}ntgen-Museum" in Remscheid (Germany) is the unique institution worldwide that researches and documents the life and work of the first Nobel Prize winner in physics, Wilhelm Conrad R{\"o}ntgen, and the effects of his discovery of X-rays. As an integral part of the museum, the R{\"o}Lab laboratory offers visitors the opportunity to gain practical experience in X-rays, optics and technology through own experiments. As part of a joint development project, students from Aschaffenburg University of Applied Sciences are currently designing a visitor experiment on astronomical X-ray optics for the museum´s R{\"o}ntgen laboratory. An optical set-up with visible light illustrates the focusing principle of X-ray telescopes, e. g. for wide-angle optics based on the lobster-eye principle. Display boards explain the optics of various types of telescopes with accompanying text and corresponding illustrations. Modern X-ray observatories such as CHANDRA, XMM-Newton and eROSITA are presented clearly. Once implemented, the new visitor experiment inside the "Deutsches R{\"o}ntgen-Museum" aims to inspire young researchers with enthusiasm for the fascinating world of X-ray optics and X-ray astronomy.}, subject = {Deutsches R{\"o}ntgen-Museum}, language = {en} } @inproceedings{HudecStieglitzDoehringetal.2025, author = {Hudec, Rene and Stieglitz, Veronika and D{\"o}hring, Thorsten and Friedrich, Peter and Burwitz, Vadim}, title = {Novel X-ray optics developed within the AHEAD2020 project}, publisher = {DGaO}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2025}, abstract = {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 (LE) and Kirkpatrick-Baez (KB) X-ray modules, based on the Multi Foil Optics technology (MFO). In addition, two major events were organized, namely a students workshop in December 2023 and a summer school in May 2024. The KB optics represents a promising and cost effective alternative to the currently used Wolter I telescopes. The LE X-ray optics, based on the Schmidt design, has a wide field of view (FOV) with a short focal length, making it suitable for CubeSat application. Thereby the 2D LE optics consist of two orthogonal sub-modules of flat smooth reflecting foils, each sub-modules focuses in one direction. The advantage of such optics is that it preserves the angular resolution throughout the FOV even for off-axis points, as demonstrated by simulations and measurements. There was a collaboration with Aschaffenburg University in design, development, and testing of the double LE module HORUS, comparing different reflecting coatings.}, subject = {R{\"o}ntgenoptik}, language = {en} } @article{KronebergerStanikDoehring2025, author = {Kroneberger, Monika and Stanik, Eva and D{\"o}hring, Thorsten}, title = {Parameter optimization for the infrared curing process of powder coatings using the NAPUBEST prototype and optical simulations}, series = {EPJ Web of Conferences}, volume = {335}, journal = {EPJ Web of Conferences}, editor = {El Gawhary, O. and Witte, S. and Moreno, I.}, publisher = {EDP Sciences}, issn = {2100-014X}, doi = {https://doi.org/10.1051/epjconf/202533503035}, pages = {1 -- 2}, year = {2025}, abstract = {In line with the energy transition, it is desirable to replace fossil fuels in the curing process of industrial powder coatings. Infrared heating is the considered method here. IR-emitter arrangement in the reflective heating chamber, their geometry and the dwell time of the components are crucial for a successful and efficient process. Process optimization has to consider the optical parameter variation of the powder coating during the procedure. Measurements in the NAPUBEST prototype are compared with optical simulations of the setup to get the simulation parameters in agreement with reality and to provide a foundation for the layout of industrial processes.}, subject = {Pulverlack}, language = {en} } @inproceedings{HudecStieglitzDoehringetal.2025, author = {Hudec, Rene and Stieglitz, Veronika and D{\"o}hring, Thorsten and Friedrich, Peter and Burwitz, Vadim}, title = {Novel X-ray optics developed within the AHEAD2020 project}, series = {DGaO-Proceedings}, volume = {2025}, booktitle = {DGaO-Proceedings}, number = {126}, publisher = {DGaO}, organization = {Czech Technical University in Prague}, issn = {1614-8436}, pages = {1 -- 2}, year = {2025}, abstract = {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.}, subject = {R{\"o}ntgenoptik}, language = {en} } @misc{DoehringStieglitzBurwitzetal.2021, author = {D{\"o}hring, Thorsten and Stieglitz, Veronika and Burwitz, Vadim and Hartner, Gisela and M{\"u}ller, Thomas and Schmidt, Thomas and Rukdee, Surangkhana and Friedrich, Peter and Sahin, Fatih and HUdec, Rene}, title = {Charakterisierung von Weitwinkel-R{\"o}ntgenteleskopen in der Testanlage PANTER}, series = {DGaO Jahrestagung}, volume = {2021}, journal = {DGaO Jahrestagung}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2021}, abstract = {Im Rahmen einer bayerisch-tschechischen Kooperation entstanden zwei mechanisch baugleiche R{\"o}ntgenteleskope, best{\"u}ckt mit Gold- und Iridium-beschichteten Planspiegeln. Die Charakterisierung der nach dem {\"a}gyptischen Gott HORUS benannten Teleskope erfolgte an der R{\"o}ntgentestanlage PANTER des Max-Plack-Instituts f{\"u}r extraterrestrische Physik. Diese Vakuum-Testanlage simuliert parallel auf die Teleskope einfallendes Sternenlicht, wobei hier die Strahlung aus einer R{\"o}ntgenquelle in 120 Metern Abstand stammt. Die Messungen selbst fanden in einer daran angebauten 12 Meter langen Testkammer von 3,5 Metern Durchmesser statt. Im M{\"a}rz 2021 sahen die HORUS-Teleskope zum erstem Mal R{\"o}ntgenlicht. W{\"a}hrend der Testkampagne von ca. 54 Stunden Dauer wurden 536 Einzelmessungen an den beiden Teleskopen durchgef{\"u}hrt, bei denen Photonenenergien und Einfallswinkel variiert wurden. Von einer empfindlichen CCD-Kamera, einem Prototyp der eROSITA-Satellitenkamera, wurden hierbei insgesamt 11.153.574 R{\"o}ntgenphotonen individuell detektiert, analysiert und digital verarbeitet. Die beiden Weitwinkel-R{\"o}ntgenteleskope haben eine Winkelaufl{\"o}sung von circa 4 Bogenminuten und eine Brennweite von rund zwei Metern.}, subject = {R{\"o}ntgenstrahlung}, language = {de} } @misc{DoehringPreglerKrivanekovaetal.2025, author = {D{\"o}hring, Thorsten and Pregler, Jan and Krivanekova, Lucia and Hildenbrand, Georg}, title = {Strahlungsmessungen beim Erstflug des Stratosph{\"a}renballon-Experiments ASTRABAX}, series = {DGaO-Proceedings}, volume = {2025}, journal = {DGaO-Proceedings}, number = {126}, publisher = {DGaO}, organization = {TH Aschaffenburg}, pages = {1 -- 2}, year = {2025}, abstract = {Mit dem Aschaffenburger Stratosph{\"a}ren-Ballon-Experiment („ASTRABAX") werden Experimente zu Material- und Biowissenschaften unter extremer Strahlungsexposition in großer H{\"o}he durchgef{\"u}hrt. Der erste von drei geplanten Ballonfl{\"u}gen startete Mitte Oktober 2024 im norddeutschen Bad Pyrmont und erreichte eine Flugh{\"o}he von fast 35 km. Der Schwerpunkt der physikalischen Experimente lag auf der Vermessung des UV-C-Spektralbereichs mit einem Miniatur-UV-VIS-Spektrometer und der Strahlungsdosimetrie mit einem Geigerz{\"a}hler. In einem zweiten Satz von Experimenten wurde die Wirkung der Bestrahlung auf Polydopaminproben untersucht, welche derzeit f{\"u}r Beschichtungen von astronomischen R{\"o}ntgenspiegel entwickelt werden. Die Ballongondel enthielt auch Proben biologischer Zellen, die hier gleichzeitig einer niedrig dosierten Strahlung von hochenergetischen Partikeln, Gammastrahlen und UV-Strahlung ausgesetzt wurden. Experimente unter solchen nat{\"u}rlichen stratosph{\"a}rischen Bedingungen sind f{\"u}r atmosph{\"a}rische H{\"o}henfl{\"u}ge, bemannte Raumfahrtmissionen, vergleichbare Expositionen bei anderen Objekten des Sonnensystems und die strahlenbiologische Forschung von Bedeutung.}, subject = {Stratosph{\"a}ren-Ballon}, language = {de} } @inproceedings{StanikPreglerDoehringetal.2025, author = {Stanik, Eva and Pregler, Jan and D{\"o}hring, Thorsten and K{\"a}tker, Anna and Busch, Uwe and Friedrich, Peter}, title = {A visitor experiment on astronomical X-ray optics for the "Deutsches R{\"o}ntgen Museum"}, series = {Proceedings of SPIE}, volume = {2025}, booktitle = {Proceedings of SPIE}, number = {13531}, publisher = {SPIE}, organization = {Technische Hochschule Aschaffenburg}, pages = {1 -- 1}, year = {2025}, abstract = {The "Deutsches R{\"o}ntgen Museum" in Remscheid is the unique institution worldwide that researches and documents the life and work of the first Nobel Prize winner in physics, Wilhelm Conrad R{\"o}ntgen and the effects of his discovery of X rays. As an integral part of the museum, the R{\"o}Lab laboratory offers visitors the opportunity to gain practical experience in X rays, optics and technology through own experiments. As part of a joint development project, students from Aschaffenburg University of Applied Sciences are currently designing a visitor experiment on astronomical X ray optics for the museum laboratory.}, subject = {Deutsches R{\"o}ntgen-Museum}, language = {en} } @misc{StanikDoehringReesetal.2025, author = {Stanik, Eva and D{\"o}hring, Thorsten and Rees, Paul and Kroneberger, Monika and Stanik, Martin}, title = {Infrared heating for a sustainable powder coating technology}, volume = {2025}, publisher = {DGaO}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2025}, abstract = {The recent energy crisis revealed the dependence of many manufacturing companies on fossil fuels Industrial processes need to be transformed into sustainable alternatives For powder coatings, which traditionally rely on gas or oil heating systems, infrared radiation can deliver the required process heat The strong dependence of the IR absorption on the geometry of the irradiated parts as well as on the color and sort of the coating powder has to be considered before the implementation of this innovative heating The aim of the NAPUBEST project (German abbreviation for Nachhaltige Pulverbeschichtungs Technologie which means "Sustainable Powder Coating Technology") is to get a better understanding of these correlations In our laboratory, we realized a prototype of an IR oven for test measurements The high reflectivity of silver coated reflector sheets facilitates the concentration of infrared radiation inside the oven. On the other hand, the absorption of powder coated samples in different paint colors has an impact on the heating efficiency First tests of the equipment and measurements of the angular dependence of the reflectivity of various coated samples are presented.}, subject = {Infrarotheizung}, language = {en} } @inproceedings{KronebergerStanikDoehring2025, author = {Kroneberger, Monika and Stanik, Eva and D{\"o}hring, Thorsten}, title = {Optik-Simulation f{\"u}r die Energiewende am Beispiel eines industriellen Infrarot-Heizofens}, series = {DGaO-Proceedings}, volume = {2025}, booktitle = {DGaO-Proceedings}, number = {126}, publisher = {DGaO}, organization = {DigitX}, issn = {1614-8436}, pages = {1 -- 2}, year = {2025}, abstract = {Um fossile Brennstoffe in der industriellen Pulverlackbeschichtung zu ersetzen, kann Infrarottrocknung eingesetzt werden. F{\"u}r komplexe Geometrien, bei denen eine Verschattung die Effizienz der Infrarot-Aush{\"a}rtung mindert, sind die Anordnung der Infrarotstrahler in der reflektierenden Heizkammer, deren Geometrie und die Verweilzeit der Bauteile die Schl{\"u}ssel f{\"u}r erfolgreiche Prozesse.}, language = {de} } @inproceedings{DoehringPreglerKrivanekovaetal.2025, author = {D{\"o}hring, Thorsten and Pregler, Jan and Krivanekova, Lucia and Hildenbrand, Georg}, title = {Strahlungsmessungen beim Erstflug des Stratosph{\"a}renballon-Experiments ASTRABAX}, series = {DGaO-Proceedings}, volume = {2025}, booktitle = {DGaO-Proceedings}, number = {126}, publisher = {DGaO}, organization = {TH Aschaffenburg}, issn = {1614-8436}, pages = {1 -- 2}, year = {2025}, abstract = {Der erste von drei geplanten Ballonfl{\"u}gen beim Aschaffenburger Stratosph{\"a}ren- Ballon-Experiment („ASTRABAX") startete im Oktober 2024 in Bad Pyrmont und erreichte eine Flugh{\"o}he von fast 35 km. Der Schwerpunkt der physikalischen Experimente lag auf der Vermessung des UV-C-Spektralbereichs mit einem Miniatur-Spektrometer und der Strahlungsdosimetrie mit einem Geigerz{\"a}hler.}, language = {de} } @inproceedings{StanikDoehringReesetal.2025, author = {Stanik, Eva and D{\"o}hring, Thorsten and Rees, Paul and Kroneberger, Monika and Stanik, Martin}, title = {Infrared heating for a sustainable powder coating technology}, series = {DGaO-Proceedings}, volume = {2025}, booktitle = {DGaO-Proceedings}, number = {126}, publisher = {DGaO}, organization = {TH Aschaffenburg}, issn = {1614-8436}, pages = {1 -- 2}, year = {2025}, abstract = {Industrial processes need to be transformed into sustainable alternatives. For powder coatings, which traditionally rely on gas or oil heating systems, infrared radiation can deliver the required process heat. The aim of the NAPUBEST project is to evaluate the possibilities of infrared radiation in the powder coating process. In our laboratory, we realized a prototype of an IR oven for test measurements.}, language = {en} } @misc{KronebergerStanikDoehring2025, author = {Kroneberger, Monika and Stanik, Eva and D{\"o}hring, Thorsten}, title = {Optik-Simulation f{\"u}r die Energiewende am Beispiel eines industriellen Infrarot-Heizofens}, series = {DGaO Proceedings, 126. Tagung}, journal = {DGaO Proceedings, 126. Tagung}, publisher = {DGaO}, organization = {DigitX}, pages = {1 -- 1}, year = {2025}, abstract = {Im Rahmen der Energiewende sollen fossile Brennstoffe auch im Heizofen einer industriellen Pulverlackbeschichtung ersetzt werden. In der Stahlindustrie ist die Infrarottrocknung von ebenen Stahlband-Oberfl{\"a}chen ein bereits seit Jahren bew{\"a}hrtes Verfahren. Pulverlack-Beschichtungen werden jedoch oft auf komplexe Geometrien aufgetragen, bei denen eine Verschattung die Effizienz der Infrarot-Aush{\"a}rtung mindert. Die Anordnung der Infrarotstrahler in der reflektierenden Heizkammer, deren Geometrie und die Verweilzeit der Bauteile sind daher die Schl{\"u}ssel f{\"u}r erfolgreiche Prozesse. Zur Verfahrensoptimierung m{\"u}ssen zudem die optischen Parameter der Pulverlacke w{\"a}hrend des Prozesses bekannt sein, um die n{\"o}tige Strahlungsleistung an Bauteile und unterschiedliche Lacke anpassen zu k{\"o}nnen. Messungen in der NAPUBEST-Prototypanlage werden daher mit optischen Simulationen des Aufbaus abgeglichen, um die Simulationsparameter an die Messergebnisse anzupassen und damit die Grundlage f{\"u}r die Auslegung von industriellen Prozessen zu gew{\"a}hrleisten. Hierbei wird Infrarotstrahlung mehrerer Wellenl{\"a}ngen ber{\"u}cksichtigt, um in unterschiedlichen Ofenzonen ben{\"o}tigte Aufheiz- und Haltephasen zu verwirklichen.}, subject = {Infrarotheizung}, language = {de} } @misc{HudecNovakovaPritzletal.2021, author = {Hudec, Rene and Novakova, Hana and Pritzl, Vaclav and Vojnar, Jan and D{\"o}hring, Thorsten}, title = {CubeSat mission for the observation of meteoroid impacts on Moon}, series = {DGaO Jahrestagung}, volume = {2021}, journal = {DGaO Jahrestagung}, organization = {CVUT Prague}, pages = {1 -- 1}, year = {2021}, abstract = {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.}, subject = {Impakt}, language = {en} } @article{CotroneoBassoCivitanietal.2025, author = {Cotroneo, Vicenzo and Basso, Stefano and Civitani, Marta and D{\"o}hring, Thorsten and Gibertini, Eugenio and Iovenitti, Simone and Magagnin, Luca and Pareschi, Giovanni and Sironi, Giorgia and Spiga, Daniele and Tagliaferri, Gianpiero and Valsecchi, Giuseppe}, title = {Polydopamine Coatings for Enhanced Soft X-Ray Reflectivity in Space Telescope Mirrors}, series = {ECS Meeting Abstracts}, volume = {MA2025-02}, journal = {ECS Meeting Abstracts}, number = {67}, publisher = {The Electrochemical Society}, issn = {2151-2043}, doi = {10.1149/MA2025-02673247mtgabs}, pages = {3247 -- 3247}, year = {2025}, abstract = {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.}, subject = {R{\"o}ntgenteleskop}, language = {en} } @inproceedings{BuschMichelsKaetkeretal.2025, author = {Busch, Uwe and Michels, Marcel and K{\"a}tker, Anna and D{\"o}hring, Thorsten and Stanik, Eva}, title = {Historical X ray images selected for UNESCO's Memory of the World Register}, volume = {16}, publisher = {16th International Conference on Astronomical X-ray Optics}, address = {Prag}, organization = {Deutsches R{\"o}ntgenmuseum Remscheid}, pages = {1 -- 1}, year = {2025}, abstract = {The Deutsches R{\"o}ntgen Museum" in Remscheid (Germany) is the institution that uniquely and comprehensively explores and documents the life and work of Wilhelm Conrad R{\"o}ntgen and the impact of his discovery. It preserves a collection of X- ray images taken by W. C. R{\"o}ntgen during his research. Among them are three images of R{\"o}ntgen's own hands and those of his wife, Anna Bertha. Three more images show R{\"o}ntgen'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 R{\"o}ntgen'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 R{\"o}ntgen ´ s birth town Remscheid. Representatives of the German UNESCO Commission, of politics, and of the German R{\"o}ntgen Society were present UNESCO is thus honoring not only R{\"o}ntgen's groundbreaking discovery of X rays, but also the cultural, scientific, and technological implications of his early radiographs. The "Deutsches R{\"o}ntgen Museum" presents six famous historical X-ray documents to the public, which are now part of UNESCO ´ s Memory of the World Register.}, subject = {Deutsches R{\"o}ntgen-Museum}, language = {en} } @inproceedings{DoehringKrivanekovaHildenbrand2025, author = {D{\"o}hring, Thorsten and Krivanekova, Lucia and Hildenbrand, Georg}, title = {ASTRABAX - Scientific results of two stratospheric balloon flights}, series = {18th Pico- and Nanosatellite Workshop 2025, Abstracts Book}, volume = {2025}, booktitle = {18th Pico- and Nanosatellite Workshop 2025, Abstracts Book}, publisher = {Julius-Maximilians-Universit{\"a}t W{\"u}rzburg}, address = {W{\"u}rzburg}, organization = {TH Aschaffenburg}, pages = {17 -- 17}, year = {2025}, abstract = {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.}, subject = {Stratosph{\"a}ren-Ballon}, language = {en} } @inproceedings{HudecDoehring2025, author = {Hudec, Rene and D{\"o}hring, Thorsten}, title = {Astrophysical and scientific payloads for CubeSats}, series = {18th Pico- and Nanosatellite Workshop 2025, Abstracts Book}, volume = {2025}, booktitle = {18th Pico- and Nanosatellite Workshop 2025, Abstracts Book}, publisher = {Julius-Maximilians-Universit{\"a}t W{\"u}rzburg}, address = {W{\"u}rzburg}, organization = {Czech Technical University in Prague}, pages = {12 -- 12}, year = {2025}, abstract = {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.}, subject = {Kleinsatellit}, language = {en} } @inproceedings{DoehringHudec2025, author = {D{\"o}hring, Thorsten and Hudec, Rene}, title = {One decade of joint Bavarian-Czech projects on astronomical X-ray optics}, volume = {2025}, number = {16}, publisher = {16th International Conference on Astronomical X-ray Optics}, address = {Prag}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2025}, abstract = {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.}, subject = {R{\"o}ntgenoptik}, language = {en} } @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} } @inproceedings{DoehringStollenwerkStadtmuelleretal.2021, author = {D{\"o}hring, Thorsten and Stollenwerk, Manfred and Stadtm{\"u}ller, Johannes and Zeising, Sebastian and Flachs, Dennis and Stehlikova, Veronika and Burwitz, Vadim and Krumrey, Michael K. and Cotroneo, Vincenzo and Klementova, Mariana}, title = {Characterisation of X-ray mirrors based on chromium-iridium tri-layer coatings}, series = {Proceedings of SPIE}, volume = {2021}, booktitle = {Proceedings of SPIE}, number = {11776}, publisher = {SPIE}, organization = {TH Aschaffenburg}, doi = {https://doi.org/10.1117/12.2592551}, pages = {1177607-1 -- 11776076}, year = {2021}, abstract = {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.}, subject = {R{\"o}ntgenspiegel}, language = {en} } @inproceedings{KhropostRiethmuellerDoehringetal.2025, author = {Khropost, Diana and Riethm{\"u}ller, Franziska and D{\"o}hring, Thorsten and Flachs, Dennis and H{\"u}lag{\"u}, Deniz and Hertwig, Andreas and Cotroneo, Vincenzo and Gibertini, Eugenio}, title = {Polydopamine: a bio-inspired polymer for X-ray mirror coatings and other technical applications}, series = {EUV and X-ray Optics: Synergy between Laboratory and Space IX}, volume = {2025}, booktitle = {EUV and X-ray Optics: Synergy between Laboratory and Space IX}, number = {13531}, editor = {Hudec, Ren{\´e} and Pina, Ladislav}, publisher = {SPIE}, doi = {10.1117/12.3056298}, pages = {135310H-1 -- 135310H-11}, year = {2025}, abstract = {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.}, subject = {R{\"o}ntgenspiegel}, language = {en} } @misc{KhropostDoehringRiethmuelleretal.2024, author = {Khropost, Diana and D{\"o}hring, Thorsten and Riethm{\"u}ller, Franziska and H{\"u}lag{\"u}, Deniz}, title = {Poly-dopamine - an organic material for X-ray mirror coatings and other technical applications}, series = {AXRO 2024 - 15th International Conference on Astronomical X-Ray Optics}, volume = {2024}, journal = {AXRO 2024 - 15th International Conference on Astronomical X-Ray Optics}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2024}, abstract = {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.}, subject = {R{\"o}ntgenspiegel}, language = {en} }