Measurement of the atmospheric electron and muon neutrino flux with the ANTARES neutrino telescope - AstroParticule et Cosmologie Accéder directement au contenu
Thèse Année : 2021

Measurement of the atmospheric electron and muon neutrino flux with the ANTARES neutrino telescope

Mesure du flux de neutrinos atmosphériques d'électrons et de muons avec le télescope à neutrinos ANTARES

Federico Versari
  • Fonction : Auteur
  • PersonId : 1237235
  • IdRef : 268470103

Résumé

High energy atmospheric neutrinos are the topic of this thesis. They are produced in particle cascades initiated by the interaction of cosmic rays consisting mainly of protons, Helium and other heavier nuclei and spanning many orders of magnitude in energy, with the nuclei of the Earth's atmosphere A possible way to detect high energy neutrinos using huge volumes of transparent natural material such as ice or sea water was proposed by Markov in 1960. High energy neutrinos undergoing weak interactions with one of the nucleons of the medium produce relativistic charged particles than can originate Cherenkov radiation. Cherenkov photons can then be detected by a lattice of photosensors. The ANTARES neutrino telescope is a three-dimensional array of photomultipliers distributed over 12 lines, installed at the bottom of the Mediterranean Sea. The detector was operated in partial configurations since March 2006 and completed in May 2008. It has been taking data continuously since then. In this thesis, a measurement of the atmospheric electron and muon neutrino spectra with the ANTARES neutrino telescope, using ten years of data collected from 2007 to 2017, is presented. This is the first atmospheric electron neutrino ux measurement ever done with ANTARES and is the first two avours atmospheric neutrino spectra measurement ever done in the energy range between around 100 GeV and 100 TeV. To achieve these results a new event selection chain has been developed to reject the background of atmospheric muons and select events induced by electron or moun neutrinos in (or close to) the instrumented volume of the detector. In addition, an unfolding procedure able to treat several signal sources has been applied. The structure of the thesis is the following: the basics of cosmic rays and the physics of atmospheric neutrinos are discussed in chapter 1, chapter 2 is dedicated to illustrate the neutrino telescopes and the topologies of events that they can detect. In chapter 3 the ANTARES neutrino telescope is described in detail. In chapter 4 the software developed for the ANTARES Monte Carlo simulations and the event reconstruction, together with a description of the boosted decision tree used in this thesis, are described. Chapter 5 contains the details of the innovative event selection chain specifically developed for this thesis. Finally, chapter 6 and 7 are dedicated to the description of the unfolding procedure of the selected events and to the calculation of the energy spectra of atmospheric electron and muon neutrinos.
Cette thèse présente une mesure combinée des spectres d'énergie des neutrinos atmosphériques d'électrons et de muons dans la gamme d'énergie comprise entre environ 100 GeV et 50 TeV avec le télescope à neutrinos ANTARES. L'analyse utilise 3012 jours de durée de vie du détecteur entre 2007 et 2017 et sélectionne 1016 neutrinos interagissant dans (ou à proximité) du volume instrumenté du détecteur, produisant des événements de type averse et des événements de piste de démarrage. La contamination par les muons atmosphériques est supprimée au niveau de quelques-uns par broyeur par différentes étapes de l'analyse de sélection, y compris un classificateur Boosted Decision Tree. La distribution des événements reconstruits se déroule en termes de flux de neutrinos d'électrons et de muons et les spectres d'énergie dérivés sont comparés aux mesures précédentes.
Fichier principal
Vignette du fichier
VERSARI_Federico_va.pdf (10.82 Mo) Télécharger le fichier
Origine : Version validée par le jury (STAR)

Dates et versions

tel-04029067 , version 1 (14-03-2023)

Identifiants

  • HAL Id : tel-04029067 , version 1

Citer

Federico Versari. Measurement of the atmospheric electron and muon neutrino flux with the ANTARES neutrino telescope. High Energy Astrophysical Phenomena [astro-ph.HE]. Université Paris Cité; Università degli studi (Bologne, Italie), 2021. English. ⟨NNT : 2021UNIP7258⟩. ⟨tel-04029067⟩
68 Consultations
6 Téléchargements

Partager

Gmail Facebook X LinkedIn More