A muon-track reconstruction exploiting stochastic losses for large-scale Cherenkov detectors

• Published in: Journal of Instrumentation
• Main Authors: Abbasi, R., Ackermann, Markus, Andeen, K., K. Gaisser, T., Gallagher, J., Ganster, E., Garrappa, S., Gerhardt, L., Ghadimi, A., Glaser, C., Glauch, T., Glüsenkamp, T., Goldschmidt, A., Anderson, T., Gonzalez, J. G., Goswami, S., Grant, D., Grégoire, T., Griffith, Z., Griswold, S., Gündüz, M., Günther, C., Haack, C., Hallgren, A., Ansseau, I., Halliday, R., Halve, L., Halzen, F., Ha Minh, M., Hanson, K., Hardin, J., Harnisch, A. A., Haungs, A., Hauser, S., Hebecker, D., Anton, G., Helbing, K., Henningsen, F., Hettinger, E. C., Hickford, S., Hignight, J., Hill, C., Hill, G. C., Hoffman, K. D., Hoffmann, R., Hoinka, T., Argüelles, C., Hokanson-Fasig, B., Hoshina, K., Huang, F.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Inst. of Physics 2021
• Subjects: info:eu-repo/classification/ddc/610; South Pole; South pole
• Online Access: https://bib-pubdb1.desy.de/record/462412; https://bib-pubdb1.desy.de/search?p=id:%22PUBDB-2021-03399%22

IceCube is a cubic-kilometer Cherenkov telescope operating at the South Pole. The main goal of IceCube is the detection of astrophysical neutrinos and the identification of their sources. High-energy muon neutrinos are observed via the secondary muons produced in charge current interactions with nuclei in the ice. Currently, the best performing muon track directional reconstruction is based on a maximum likelihood method using the arrival time distribution of Cherenkov photons registered by the experiment's photomultipliers. A known systematic shortcoming of the prevailing method is to assume a continuous energy loss along the muon track. However at energies >1 TeV the light yield from muons is dominated by stochastic showers. This paper discusses a generalized ansatz where the expected arrival time distribution is parametrized by a stochastic muon energy loss pattern. This more realistic parametrization of the loss profile leads to an improvement of the muon angular resolution of up to 20% for through-going tracks and up to a factor 2 for starting tracks over existing algorithms. Additionally, the procedure to estimate the directional reconstruction uncertainty has been improved to be more robust against numerical errors.