Skip to Main content Skip to Navigation
Theses

Reconstruction des gerbes atmosphériques et mesure de la fluorescence de l'air pour l'étude des rayons cosmiques ultra énergétiques au sein du projet EUSO

Abstract : The EUSO project (Extreme Universe Space Observatory) is an innovative concept to measure the UHECR (UltraHigh Energy Cosmic ray) spectrum by observing from space the light (air fluorescence and Cerenkov radiation) produced in the atmosphere by EAS (Extensive Air Shower).
After an overview of the scientific context and an EUSO project description, a reconstruction method of EAS seen from space is presented. This new method enable one to reconstruct the UHECR parameters (Energy, direction, Xmax) using only the fluorescence signal shape (without extra information). This method is very efficient for the horizontal EAS.
The second part of this thesis deals with the study and the measurement of the air fluorescence with the MACFLY experiment (Measurement of Air Cerenkov and Fluorescence Light Yield). After a state of the art on the air fluorescence knowledge, a model of FLY (Florescence Light Yield) proportional to the Energy released in air is proposed.
The experiment MACFLY and the data analysis method are described in detail. The experiment is composed of two devices. The first (Macfly1) which measures the fluorescence produced by only one particle measure the FLY of electron of 1.5 MeV (radioactive source), 20 GeV and 50 GeV (CERN test beam). The second (Macfly2) which measure the fluorescence produced by an electromagnetic shower, was the first experiment to measure the shower age dependence of the FLY. The pressure dependence was also measured by the two devices.
Thanks to a GEANT4 simulation program, we compare our measurements with the FLY models. The assumption of the proportionality between the FLY and the energy deposited has been checked. One finds the same result with Macfly1 and Macfly2. In the air at 950 hPa, 23°C and 0% of moisture one obtains:
FLY=19 ± 4 photons/MeV
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00010336
Contributor : Pierre Colin <>
Submitted on : Thursday, September 29, 2005 - 5:57:51 PM
Last modification on : Friday, November 6, 2020 - 3:29:00 AM
Long-term archiving on: : Friday, April 2, 2010 - 10:31:56 PM

Identifiers

  • HAL Id : tel-00010336, version 1

Collections

Citation

Pierre Colin. Reconstruction des gerbes atmosphériques et mesure de la fluorescence de l'air pour l'étude des rayons cosmiques ultra énergétiques au sein du projet EUSO. Cosmologie et astrophysique extra-galactique [astro-ph.CO]. Université Joseph-Fourier - Grenoble I, 2005. Français. ⟨tel-00010336⟩

Share

Metrics

Record views

278

Files downloads

1494