Sebastian Wozniewski

Fusion facilities like ITER and DEMO will circulate several kilograms tritium and deuterium per day in their fuel cycle. For the separation of the hydrogen isotopologues the Isotope Separation System (ISS), based on cryogenic distillation, was developed at Tritium Laboratory Karlsruhe (TLK). One challenge is to find and develop an in situ and real time method to analyse the isotopologic composition of the column content. Calibration tests with IR absorption spectroscopy (FTIR) with chemically equilibrated samples have been performed at the Tritium absorption IR Spectroscopy Experiment (TApIR). From this previous work and from literature, it is known that the dependence between IR absorbance and the concentrations is non-linear. This makes it impossible to extrapolate the calibration from equilibrium to non-equilibrium samples. This work shows a full D2, H2, and HD calibration with samples in and off the high temperature. This enables us now to measure composition of inactive liquid hydrogen samples with an accuracy of better than 5%. In addition, one of the main challenges on the way to a calibration with tritiated mixtures is shown, the IR absorbance at molecular dimers, which tremendously increases the complexity of IR absorption spectra.

The PUNCH4NFDI consortium brings together scientists from the German particle physics, hadron and nuclear physics, astronomy, and astro-particle physics communities to improve the management and (re-)use of scientific data from these interrelated communities. The PUNCH sciences have a long tradition of building large instruments that are planned, constructed and operated by international collaborations. While the large collaborations typically employ advanced tools for data management and distribution, smaller-scale experiments often suffer from very limited resources to address these aspects. One of the aims of the consortium is to evaluate and enable or adopt existing solutions. Instances of a prototype federated and distributed computing and storage infrastructure have been set up at a handful of sites in Germany. This prototype is used to gain experience in running of scientific workflows to further guide the development of the Science Data Platform, which is an overarching goal of the consortium.

Given the urgency to reduce fossil fuel energy production to make climate tipping points less likely, we call for resource-aware knowledge gain in the research areas on Universe and Matter with emphasis on the digital transformation. A portfolio of measures is described in detail and then summarized according to the timescales required for their implementation. The measures will both contribute to sustainable research and accelerate scientific progress through increased awareness of resource usage. This work is based on a three-days workshop on sustainability in digital transformation held in May 2023.

The IR spectra of liquid hydrogen isotopologues (Q2 = H2, D2, T2, HD, HT, DT) are dominated by the interaction induced absorption. Therefore, the complexity tremendously increases with the number of different isotopologues in the sample. As we aim for a system independent calibration of IR absorption spectroscopy against all six isotopologues and three ortho–para ratios, we need a minimal and complete set of descriptors to predict the spectra and to decrease the needed calibration effort. For this, we grouped the absorption lines into three groups: absorption on monomers, phonons, and molecular dimers. In particular, molecular dimers contribute to the absolute number of absorption lines in the spectra of mixed isotopologues. To develop and test the set of descriptors, we make use of three spectra: a pure H2 sample, a pure D2 sample, and a mixed H2–D2 sample. We show a detailed analysis of these three spectra in the first and second vibrational branch in the range from 2000 cm−1 to 9000 cm−1. The set of descriptors found within this work can be used to identify and predict all lines in this range for liquid H2–D2mixtures.

Wirkungsquerschnitte der Erzeugung von Higgs-Bosonen in Proton-Proton-Kollisionen werden im Zerfallskanal zu zwei Tau-Leptonen gemessen. Hierfur werden 137,2/fb Daten verwendet, die von der CMS-Kollaboration wahrend Run-2 des Large-Hadron-Colliders aufgenommen wurden. Die Messung umfasst die dominanten Produktionskanale, Gluonfusion und Vektorbosonfusion, und wird differentiell in bis zu zwolf kinematischen Regionen durchgefuhrt. Multiklassifikation basierend auf neuronalen Netzwerken wird zur Klassifizierung der Kollisionsereignisse den angestrebten Signalkomponenten entsprechend und zur Verbesserung der Sensitivitat eingesetzt.