Full text
| |
| Author(s): |
Allan Machado Payeras
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Física Gleb Wataghin |
| Defense date: | 2023-12-15 |
| Examining board members: |
Anderson Campos Fauth;
Carola Dobrigkeit Chinellato;
Sandro Guedes de Oliveira;
Rita de Cássia dos Anjos;
Hélio Nogima
|
| Advisor: | Anderson Campos Fauth |
| Abstract | |
The main objective of the Pierre Auger Observatory is the investigation of the nature of cosmic rays with energies exceeding 1 EeV, known as ultra-high energy cosmic rays (UHECRs). The Observatory employs two experimental techniques to detect extensive air showers (EASs) induced by primary cosmic rays. The surface detector (SD) consists of an array of 1660 water-Cherenkov detectors (WCDs), spanning an area of approximately 3 000 km2. Additionally, 24 fluorescence telescopes are distributed around the SD. Since the beginning of its operation in 2004, the Observatory has significantly advanced the understanding of UHECRs. However, the necessity for a larger volume of data sensitive to the composition of cosmic rays for energies above 40 EeV became evident. This information is the key to understanding astrophysical sources and processes capable of producing such energetic particles. To collect more data sensitive to composition, the Observatory is undergoing an upgrade of its surface detector, called AugerPrime. The main component is the installation of scintillator plates (SSD) on top of each WCD and their associated new electronics, called the upgraded unified board (UUB). In this doctoral research, we analysed the data from the first AugerPrime stations in the field, with the aim of validating the Observatory upgrade. Comparing the data from stations equipped with UUB with those from the previous electronics, called unified board (UB), we found that the signal from both electronics is compatible within the expected uncertainty, with non-linearity and bias below 3% in both channels. Regarding event reconstruction, we demonstrated that the energy determination provided by the AugerPrime stations exhibits biases within 5% relative to UB stations. Additionally, we verified that the zenith and azimuth angles of the events are determined without bias between the two electronics. These results validate the Observatory upgrade and ensure compatibility and a smooth transition between the data collected before and after the implementation of AugerPrime. To achieve the scientific goals of the upgrade regarding composition identification, it is essential to separate the muonic and electromagnetic components of EASs. In the second part of our research, we developed a method that accomplishes this separation using the signals from AugerPrime detectors. The method provides the muonic fraction with a bias below 6%... The abstract is available with the full electronic document (AU) | |
| FAPESP's process: | 19/15899-5 - Measurement of muon production depths using the AugerPrime detectors |
| Grantee: | Allan Machado Payeras |
| Support Opportunities: | Scholarships in Brazil - Doctorate |