Analysis tools and methods for tritium data taking with the KATRIN experiment

Das KArlsruhe TRItium Neutrino (KATRIN) Experiment ist konstruiert, um die Neutrinomasse mit einer bisher unerreichten Sensitivität von 200 meV (90 % C.L.) zu bestimmen. Dafür kombiniert KATRIN eine starke gasförmige Tritiumquelle mit einem hochauflösendem MAC-E-Filter-Spektrometer. Seit der Fertigstellung des experimentellen Aufbaus im Herbst 2016 hat das KATRIN-Experiment mehrere zentrale Meilensteine erreicht. In der vorliegenden Arbeit wird ein Gasmodell für den letzten dieser Meilensteine - die erste Tritium-Zirkulation in der Tritium-Quelle im Mai und Juni 2018 - vorgestellt, und mit unterschiedlichen Messmethoden verglichen. Mit Hilfe des Gasmodells werden die ersten Tritiumspektren analysiert, wobei verschiedene Methoden zur Berücksichtigung von Systematiken am Beispiel des Gasmodells untersucht werden. Vorbereitend auf die kommenden Neutrinomassendaten werden in dieser Arbeit Methoden für eine blinde Neutrinomassenanalyse von $\beta$-Zerfall-basierten Tritiumspektren vorgestellt, miteinander verglichen, und an Hand von Kryptondaten getestet. Die Arbeit schließt mit einem Ausblick auf das Potential von KATRIN, Physik jenseits der Neutrinomasse zu untersuchen. Für drei Beispiele wird exemplarisch die statistische Sensitivität von KATRIN bestimmt und mit bestehenden experimentellen Erkenntnissen verglichen

Tritium beta decay with additional emission of new light bosons

We consider tritium beta decay with additional emission of light pseudoscalar or vector bosons coupling to electrons or neutrinos. The electron energy spectrum for all cases is evaluated and shown to be well estimated by approximated analytical expressions. We give the statistical sensitivity of Katrin to the mass and coupling of the new bosons, both in the standard setup of the experiment as well as for future modifications in which the full energy spectrum of tritium decay is accessible

Kassiopeia: A Modern, Extensible C++ Particle Tracking Package

The Kassiopeia particle tracking framework is an object-oriented software package using modern C++ techniques, written originally to meet the needs of the KATRIN collaboration. Kassiopeia features a new algorithmic paradigm for particle tracking simulations which targets experiments containing complex geometries and electromagnetic fields, with high priority put on calculation efficiency, customizability, extensibility, and ease of use for novice programmers. To solve Kassiopeia's target physics problem the software is capable of simulating particle trajectories governed by arbitrarily complex differential equations of motion, continuous physics processes that may in part be modeled as terms perturbing that equation of motion, stochastic processes that occur in flight such as bulk scattering and decay, and stochastic surface processes occuring at interfaces, including transmission and reflection effects. This entire set of computations takes place against the backdrop of a rich geometry package which serves a variety of roles, including initialization of electromagnetic field simulations and the support of state-dependent algorithm-swapping and behavioral changes as a particle's state evolves. Thanks to the very general approach taken by Kassiopeia it can be used by other experiments facing similar challenges when calculating particle trajectories in electromagnetic fields. It is publicly available at https://github.com/KATRIN-Experiment/Kassiopei

Fungemia and necrotic lymph node infection with Sporopachydermia cereana in a patient with acute myeloid leukemia

Sporopachydermia cereana is a rare yeast found in necrotic cactus tissue, predominantly in the Americas. Infection in humans with clinical data has only been reported in four patients so far, all of whom died, either directly from the pathogen or from other complications of immunosuppression. Treatment of the yeast is complicated by difficulties in identification of the pathogen with conventional diagnostic techniques and by intrinsic resistance to echinocandins. The first patient to survive a disseminated infection with S. cereana is presented herein. The patient had acute myeloid leukemia and was treated successfully with antifungal therapy and subsequently underwent a successful allogeneic hematopoietic stem cell transplantation