First observation of the cosmic ray shadow of the Moon and the Sun with KM3NeT/ORCA

• Published in: The European Physical Journal C
• Main Authors: Aiello, S., Anguita López, Mancia, Díaz García, Antonio Francisco, Navas Concha, Sergio
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Nature 2023
• Subjects: Orca
• Online Access: https://hdl.handle.net/10481/85194; https://doi.org/10.1140/epjc/s10052-023-11401-5

This article reports the first observation of the Moon and the Sun shadows in the sky distribution of cosmic-ray induced muons measured by the KM3NeT/ORCA detector. The analysed data-taking period spans from February 2020 to November 2021, when the detector had 6 Detection Units deployed at the bottom of the Mediterranean Sea, each composed of 18 Digital Optical Modules. The shadows induced by the Moon and the Sun were detected at their nominal position with a statistical significance of 4.2 and 6.2 , and an angular resolution of and , respectively, consistent with the prediction of from simulations. This early result confirms the effectiveness of the detector calibration, in time, position and orientation and the accuracy of the event direction reconstruction. This also demonstrates the performance and the competitiveness of the detector in terms of pointing accuracy and angular resolution. Agence Nationale de la Recherche (ANR) ANR-15-CE31-0020 Centre National de la Recherche Scientifique (CNRS) Commission Europeenne (FEDER fund), France Marie Curie Actions European Union (EU) Institut Universitaire de France (IUF), France LabEx UnivEarthS, France ANR-10-LABX-0023 ANR-18-IDEX-0001 Paris ile-de-France Region, France German Research Foundation (DFG) Greek Ministry of Development-GSRT Istituto Nazionale di Fisica Nucleare (INFN), Ministero dell'Universita e della Ricerca (MIUR), PRIN 2017 program Italy NAT-NET 2017W4HA7S Ministry of Higher Education, Scientific Research and Innovation, Morocco Arab Fund for Economic and Social Development Netherlands Organization for Scientific Research (NWO) Netherlands Government National Science Centre, Poland National Authority for Scientific Research (ANCS), Romania MCIN/AEI PID2021-124591NB-C41 PID2021-124591NB-C42 PID2021-124591NB-C43 ERDF A way of making Europe European Union (EU) Center for Forestry Research & Experimentation (CIEF) ASFAE/2022/023 ASFAE/2022/014 Programa Prometeo of the Generalitat Valenciana PROMETEO/2020/019 ...