Leiden University Student Repository

Murris, Casper 2020

Studies of the cosmic ray shadow of the moon and the sun in the KM3NeT/ORCA detector

Bachelor thesis | Natuurkunde (BSc)

open access

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