This thesis focuses on the task of separating detector events caused by atmospheric neutrinos from those caused by atmospheric muons. Performance on this task is analysed using simulated data of...Show moreThis thesis focuses on the task of separating detector events caused by atmospheric neutrinos from those caused by atmospheric muons. Performance on this task is analysed using simulated data of these events as they are detected in the KM3NeT/ORCA10 detector setup. We present a new procedure for training the Machine Learning (ML) classifiers that handle this separation task. This most notably includes separating the data into track- and shower- like events, and training separate classifiers on these subsets of data. We show a significant improvement in the resulting neutrino signal when compared to the current classification procedure.Show less
The research collaboration KM3NeT is currently constructing neutrino telescopes at two sites in the Mediterranean Sea. The pointing accuracy of these two telescopes is of high importance to be able...Show moreThe research collaboration KM3NeT is currently constructing neutrino telescopes at two sites in the Mediterranean Sea. The pointing accuracy of these two telescopes is of high importance to be able to trace detected neutrinos back to their cosmic sources. Pointing can be cross checked with the cosmic ray shadow of the moon respectively the sun. In this research first the effects of mispointing of the KM3NeT/ORCA detector on the 2D map of the moon were evaluated. It is shown how various mispointing does in fact distort the 2D-map of a celestial object. Secondly the first six months of data with 4 lines of the KM3NeT/ORCA detector were used to investigate the cosmic ray shadow from both the sun and the moon. Extrapolated simulations for a year show that the statistics are currently not sufficient for a significant deficit of particles in the neighbourhood of the moon and the sun. In the analysis of the ORCA4 data the background of the moon and sun signal was evaluated using fake sources, following the path of the moon and with a given time delay. The background showed significant differences between different fake sources and also could be shown to behave differently for the moon and the sun. Further research is needed to investigate the discovered features and be able to recover the signal from the moon and sun shadowsShow less
The KM3NeT/ORCA experiment will use part of the detector which is currently being built in the Mediterranean Sea to determine the neutrino mass hierarchy by measuring the pattern of atmospheric...Show moreThe KM3NeT/ORCA experiment will use part of the detector which is currently being built in the Mediterranean Sea to determine the neutrino mass hierarchy by measuring the pattern of atmospheric neutrino oscillations. In this thesis, in addition to the neutrino oscillations in the Earth, the oscillations in the atmosphere have been included in the simulations and the impact of the atmosphere on the measurements has been evaluatedShow less
In this paper a new method of distinguishing shower-like from track-like neutrino interaction events using event reconstruction data is introduced. This method is then used to minimise the error...Show moreIn this paper a new method of distinguishing shower-like from track-like neutrino interaction events using event reconstruction data is introduced. This method is then used to minimise the error that a shower-like event is misidenti ed as a track-like event and vice versa, which is necessary for measuring the neutrino mass hierarchy in ORCA. In its current format, the method leads to errors of around 0.40 for noisy simulation data and approximately 0.15 for noiseless data. However, the method can still be extended to take into account more information of the reconstructions, thereby possibly improving the results.Show less
